wood-notes

The demise of my first kit and birth of my next build

2011-10-23T22:33:00.000-04:00

Confession time.

The kit building saga was exciting, fraught with challenges and ultimately satisfying in the results. I played the mandolin for a while and even brought it to our Irish session, where it was well received. However, increasing tuning problems had me concerned that something was wrong. Time helped reveal the deadly problem - the mandolin was collapsing - folding on itself, if you will. Slowly but surely the top was bending right across the sound hole.

Here is a discussion on the mandolincafe.com builders forum where we talked about the problems of this instrument.

By now, the top has cracked and the mandolin is not usable as an instrument. However, it is very useful as a scratch-pad for learning and experimentation. Only recently I pulled out all of the frets and practiced re-fretting the neck. I may even end up cutting off the head stock (because I like the way it looks) and turn it into some ornament

But out of the ashes emerges a new project. I decided to build my next mandolin from scratch and not use a kit. There are several reasons for this:

The kit that I used, while great for a beginner, has certain parts pre-made, such as a top already attached to a pre-made sides/rim assembly, the neck was complete with a pre-ftetted finger board etc. I want to learn how to build all of the parts
The fact that the top was already attached to the sides was an inconvenience when it came to doing the final sound board graduation, fitting the braces and some steps.
I want to build a type of mandolin that is not available as a kit and use my choice of materials

And this brings me to the choice of the next build. I decided to use the plans made by Graham McDonald for a "Celtic Model". I will be following the design and build methods outlines in his book The Mandolin Project

This mandolin will have several distinctive design features:

Carved Adirondak Spruce top
Back, sides and neck made out of black walnut
The back will be flat but curved on a radius similar to a steel string guitar back
Oval hole

I am hoping for a more resonant and sweet sounding mandolin for use in Irish traditional music, as compared with my Gibson-like A-style f-hole Flatiron mandolin

Future entries will show photos that document the build and occasional notes about the experience

Complete!!

2009-10-11T14:11:00.002-04:00

Here is the completed mandolin after ~8-9 coats of tru-oil, micromesh 6000-12000 and buffing with Meguiar #2 polish. This is the first time I've ever used micromsh and I like it a lot, in spite of the high price. I then put a buffing foam disk (from StewMac) into my hand drill, put the hand drill in a vice and used it to polish the mandolin.

Here are some photos of the final instrument

Back to work on the finish

2009-09-20T18:37:00.016-04:00

The water disaster in my previous (rented) house damaged tools, supplies, not to mention many personal items in the house. I have since relocated to central NJ and can finally get back to finishing the mandolin. My new goal is to complete this one by the end of the month or early Oct at the latest. There isn't much remaining.

I spent some time final-sanding the instrument - went up to 320 and spent (what I thought was) much time sanding. I found it convenient to use small hard (wood) and softer (closed cell stiff foam) blocks to hold the sanding paper. The hard block was useful on flat surfaces such as the head plate and the sides of the mandolin. The softer block conformed better to the curves of the instrument.

Next I used blue masking tape (painter's tape) to protect the entire fingerboard and as much of the binding as I could. Here is a a photo of the mandolin just before applying dye

I applied a thin coat of shellac (2-lb cut) to try and seal the wood somewhat and avoid "splotchiness". I knew I wanted to do it for the spruce top ,but ended up also using it on the rest of the maple body. I don't know if this was a good thing to do. It may prevent some of the figure (as little as exists in this kit) to pop but I did it anyway. I mixed my own shellac from flakes and dissolved them in denatured alcohol.

Dying the mandolin was a nerve-wrecking process - almost as much as the binding. Mistakes are very costly. Being a total beginner, all I could hope for was a reasonable finish job. I had practiced dying on some sample spruce and maple but still it's all very new to me and reading about it leaves a lot of unknowns , revealed only when you do the real thing with your hands.

I am using aniline dye powder (from LMII) mixed with denatured alcohol. I started with the amber and thought it was too brown for my taste. I wanted something a little more reddish and so I added small amounts of red to the mixed amber and kept on testing on wood until I got the shade I wanted. I think it was easier for me to get to this color starting with amber rather than starting with all primary colors. I mixed it well and let the dye solution sit overnight. Looking back, I think I should have strained the dye before using it because some aniline dye grains remained in the solution and eventually got on the wood. Next time.

There are some aspects to dye that I did not fully appreciate until now - must be obvious to anyone who has used dye before....

For example - the color on the wood gets darker and darker, with every swipe of the pad. In other words, it's not like paint where if you cover the surface with it, and then come back again, it will remain the same color. Here, the wood is never fully covered. You are distributing tiny dye particles suspended in alcohol. Therefore, every time you dip the pad in dye and bring it to the wood, you are adding color. On one hand this can be useful if you want darker and lighter areas. But it makes it hard to get even coloration across the instrument.

One good thing about this alcohol-based dye is that it does not raise the grain because the alcohol evaporates so fast.

The end result was a reasonably-even color over the maple and some splotchiness on the spruce, in spite of the shellac wash coat. I'm not sure what the reason is. Could be the wood. Could be that my sanding was not as good as could be. Could be that I worked the dye in for too long. However, I am not going to attempt to change it. It's time to complete the instrument and move on to the next project. I am happy with the color though.

Here are some photos of the mandolin right after dying. The tape is still on. The color is not exactly as it is in real life, due to the lighting and the camera in general but it gives the general idea.

I spent some time scraping the binding from any dye the seeped under the tape. I used an Exacto knife and worked slowly. One has to be very careful (from experience....) not to let the knife slip and scratch the instrument.... I think a simple tool can (should) be made with a blade extending out just a tiny bit to minimize the exposed edge. I'll put it on the list of things to improve in the future. Scratch repair is very difficult after the dye it on.

Today I put on two coats of Tru-Oil - my finish of choice for this mandolin. I wanted a simple and forgiving finish and I think Tru-Oil is it. My schedule is a coat in the morning and one at night when I come home from work. I use cheesecloth as a pad, rub a small amount on and wipe off any remaining oil. I want even thin coats. I plan to start rubbing the finish with 0000 steel wool after 4 coats and plan on about 10 coats total or when it looks "right".

Here are photos of the mandolin after 2 coats.

Finish will have to wait

2009-03-25T08:49:00.002-04:00

Unfortunately I have not been able to live and work in the house for the past 3 weeks due to the water damage and ongoing (way too slow) construction to repair the place. I had to work hard to remove the rust from my parrot vise and plane that suffered damage and I need to re order all of my sandpaper. The entire stack was on the table when the ceiling collapsed under the weight of water and is not usable.

The good news though is that I AM MOVING! I just rented a house and will be relocating in June. AND that house has space for a small workshop. So things are looking up even if I have to put a stop on the mandolin work for a while

The good and the bad

2009-03-07T21:01:00.005-05:00

The good news is that I made some more progress in my finish experiments. The bad news is that I cannot show the results....an unfortunate collapse of the ceiling above the work table, followed by steaming water gushing down obliterated the work...

However - we (the same famous "we" that the New Yorker magazine uses..) are to stay positive and so this is what I managed to do since the last posting:

Dye: I noticed that it was too hard to keep an even dye tone with my previous method. My idea of coming in and gently skimming the wood in one controlled motion (like an airplane landing and then taking off) turned out to be a poor one. It's just too hard to get good results. A better idea was to dilute the dye much more than I had. Then do the opposite of what I had originally said - namely, rub the dye into the wood continuously over and over until you get the desired coloration. I tried the method on the small remaining part of the wood sample and ended up with MUCH better results. That is good progress.

Finish: I applied about 6 coats of Tru-Oil diluted in mineral spirits. I think this works really well, even though I was not able to take it to a full polished finish. The thin coats go on easily with a rag and the lightest rubbing with 2000 grit paper knocked down any slight rough spots between coats. I like the richness of the finish as well. This is definitely what I will use on the mandolin.

When I started applying the Tru-Oil, I transferred some to a cotton pad and then applied it to the wood. That seemed very wasteful, as much of the oil remained in the pad. I wanted an easy method to transfer small amounts of oil to the wood before putting the pad down on it. I remembered that I had bought some pipets from stewmac and tried to use them to drop a little oil on the wood. It worked perfectly! These pipets are inexpensive and disposable, although they kept well between coat applications. I think I could end up using only one or two for the whole instrument.

I am going to set aside the finish experiments and move on to final sanding work

Playing with color

2009-02-22T21:52:00.003-05:00

Spent some time this morning playing with dye colors and trying them out on some wood samples. I had gotten some guitar spruce top "rejects" to use as stain samples as well as some pieces of maple. I sanded them "through the grits" all the way up to 220 and then applied a wash coat of shellac to one piece each of maple and spruce. Sarah was most helpful in mixing colors. She has a very good sense for these types of things.

The dye is power from LMII, dissolved in denatured alcohol. The shellac-covered wood shows more defined figure and at the same time has less blotching than the bare wood. I will be applying finish to the stained woo, to see what the final effect is

In the meantime here is a photo from today's color session

in the white

2009-02-15T21:47:00.004-05:00

Here is the mandolin "in the white". I still need to do final sanding and finish work on it, but otherwise it is functionally complete.

The tuners have been changed yet again. My first "upgrade" to Ping tuners did not yield all that much improvement. Not only did the Pings slip and and have to much play, but the edges of the string holes (in the posts) were actually sharp - sharp enough to cut and break more than one string!! I ended up ditching them and getting a set of Grover tuners from International Violin. They work perfectly and look very nice as well. I will have more close ups of the headstock and tuners once I complete the finish work

fitting the bridge

2009-02-14T22:21:00.005-05:00

I had bought an ebony bridge to replace the one that came with the kit. A good tight fit of the bridge against the contour of the mandolin top is critical for extracting maximum sound. I used a piece of sandpaper on the top and ran the bridge across it to develop the right contour. In order to help the bridge stay upright during the sanding, and not lean over, I created a simple "wagon" jig as you can see in the photos. The bottom part of the bridge screws into the jig and then you have a much wider base to run along the top. Again - this was home made. Better jigs are available through StewMac but I had to slow down the acquisition of specialized tools, at least temporarily. There is also some degree of satisfaction in making your own tools, so I was not exactly heartbroken either. By the way, the black block in the back of the jig is a piece of closed-cell foam that I stole from my kayak outfitting materials. It cuts easily, stiff enough, and glues very well. It would have been better to have a small wheel there, but this was ok.

The photos show the jig but also show the beginning of the sanding, where it's quite clear that only a small part of the bridge is coming in contact with the top. The sanding is done when you can see a full mark on the sandpaper, or when your own mark on the bridge is sanded off.

setup

2009-02-14T22:02:00.009-05:00

Once I took a close look at the frets, I realized that they were uneven in height. Using a few small straight pieces of aluminum, I was able to find the high frets. There were several of them along the neck. This needed to be corrected by sanding them flat and then crowning the tops and polishing them. For the sanding I used another sanding "stick" which I made out of a very flat angle aluminum. I cemented a piece of sandpaper onto it, as you can see below.

The flattening process was quick but it left the top of the frets quite scratched. Next time I think I'll use finer grit sandpaper even it it takes longer to flatten. To re-form the round tops of the frets I decided to use a simple triangular mill file. These are common and very inexpensive compared with the specialized crowning files on the market. However, I needed to modify the file so that the long edges would not harm the fretboard. To do that, I used the Dremel tool to grind the edges smooth. This made my tool into a safe-file as shown in the next photo.

I surrounded each fret with masking tape for the filing and then used the Dremel tool with a polishing wheel + compound to get the file scratches out as much as possible. This worked very well. I'm constatly finding new uses for the Dremel.

A big part of the setup was the making of the nut. My camera malfunctioned during that time so unfortunately I have no photos to show.

closing the box

2009-02-14T21:16:00.018-05:00

I have fallen behind on updating the blog. It's time to catch up and document what has been achieved in recent months. In spite of me acting as the world's slowest builder (not by choice...) I am close to completing the mandolin. The mandolin was officially born on February 7th, 2009. To me, this means that on that date it became functionally complete, albeit without the finish. I will post a photo of it's current state in next posting. For now, let's go over what's been done since I've left off

First, let me address my neck angle worries which I stressed over in the last posting. Although I suspect the angle is not ideal, I was able to get decent string action by cutting down the bottom of the bridge saddle to facilitate lowing it. Problem solved = major sigh of relief!

Going back in time - gluing in the lining was fairly straight forward. The kit came in with a solid thin strip for lining, rather then the more common kerf lining. I needed a lot of small clamps, and ended up using everything I had, including wooden clothes line clips with a rubber band reinforcement for extra clamping power. It worked just fine. No need to always buy specialized tools!

Once the glue dried, I continued to flatten the entire edge of the ribs/lining area so that the back plate would sit flush on it without rocking. I feared that clamping the back onto a non-flat area would induce twist in the body. In order to flatten the edge, I created a long sanding stick by taking a flat piece of wood and gluing sandpaper to it with some pray adhesive. This sanding stick method is very useful for various operations.

The big moment of closing the box came next. I approaches the task with a mixture of excitement and apprehension. The back plate was within may be 1mm of the width of the body, so aligning it for gluing was crucial. The glue would make the join slippery and every clamp would pull the back a little this or that way. The solution was a locator pin, pre-installed on the tail block. At least one end wouldbe anchored in place. I could not use a locator pin in in the neck block because , again, the precision needed in alignment. So this was a good enough compromise. I used a...wooden toothpick as the pin and drilled a hole for it in the tail block. Once it was glued in, I cut it short and put a little black marker ink on it to transfer the location to the top plate. I then drilled a shallow hole in the top plate and made sure I had a snug and perfect fit. By the way, the photo below also shows another problem with this kit. The ribs (which came pre-glued to the block) were done....less then perectly...and a visible gap is evident. Luckily most of it would be hidden behind the tailpiece. Same for the gap in the binding. No worries.

Gluing the back on took some fast and careful alignment, before the glue had a chance to set. It's really true what they say - you can never have too many clamps! I used them all - cam clamps. small F clamps, a dozen violin spool clamps. Wherever extra protection was needed, I used some leather scraps to avoid denting the wood. I love this shot. So....industrial.

Thoughts about the neck set

2008-09-09T08:45:00.002-04:00

After looking at the set neck some more, it seems that I would have to cut the bridge down too much to get useful action. Since I don' t have the back on yet, I might as well try to reset the neck. The pins have been glued in so those will be drilled out. for removing the neck, I'm thinking of making a steam injector using an old espresso machine, a hose and a basketball inflater pin. This calls for a trip to Home Depot to look for a rubber hose that can be clamped to the espresso maker and the pin

Setting the neck

2008-09-07T11:51:00.008-04:00

The neck joint was too tight and required some fine tuning but I got it close and glued the neck to the body. After the glue dried I realized that the neck angle was too shallow. This will make the action too high. Rather than disassemble the neck at this point, I've decided to cut the bridge down to reduce the action. This will be done later on. For now, the neck is in place. The tolerances on the neck were not the best and it made for a difficult alignment. For example, I think that the inlay dots are not sitting exactly on on the center line. It's starting to look like an instrument now. Oh - before gluing the neck on, I did some sanding all around where the neck extension covers the body. It's going to be hard to get in there after the neck has been set so might as well do some of it upfront.

I also shaved down the braces more. I had been waiting to get a finger plane and it worked beautifully in this tight space. I still think that a crank (or bent) small chisel would also be a good idea. I'll have to keep an eye out for one.

Completing the inlay

2008-06-14T16:59:00.007-04:00

The headstock inlay is now complete - see photo to the right.

After experimenting on the side with designs, cutting shell, routing cavities, gluing and sanding (the entire work-flow), it's time to perform it on the actual project.

I cut the final pieces by hand. using the headband magnifier has been extremely useful. If it looks good under magnification, it will look perfect to the naked eye. I don't have adequate lighting at my workbench (dining table...) and so the little led lights on the headband really help my eyes. Since the design is symmetrical, I glued two abalone pieces back to back and cut them simultaneously. This ensures identical shapes and also reduces the work time.

The shell pieces were positioned on the headstock relative to guidelines that I drew with a pencil. Before routing the cavities, I needed to scribe the outline of each piece. One method calls for painting the ebony with some tempra paint and then scribing. The idea is that you would see a clean black line through the paint. I had tried that method on the side but wasn't completely happy with it. The paint was a little thick and it was dragging as I scribed. Also, it was a little messy while routing and as a result, the cavity edge was hard to see crisply. I ended up using a different method. No paint. I glued the shell pieces temporarily on the headstock and scribed directly into the wood. See photo. Once I popped the shell pieces off, I rubbed white chalk into the scribed lines. The lines stood out very well and were easy to see throughout the routing process.

The cavities were routed using a Dremel tool, mounted into a StewMac precision router base. I ordered several cutting bits from R. L. Schmitt and I'm impressed with the quality and service. since the design has very tight corners (the diamond points), I had to use a 1/32" bit.

The pieces were dry fitted, adjusting the cavity until they pieces were almost flush with the surface. At that point everything was ready for gluing. This is a photo of the dry fitted pieces.

For cement I used slow-curing epoxy, mixed with black dye. Since the headstock overlay is made of ebony, the black epoxy would fill the small gaps around the shell and make everything look flush and neat. I put a small amount of epoxy into each cavity and pressed the shell pieces in. The excess glue oozed out and settled all around and on top of the shell. It looked messy at that point. Unfortunately I don't have a photo of that stage. I let it cure overnight.

The Next day I sanded down the dry epoxy until I reached the shell and the wood. Everything was leveled . You can see a photo of the post-sanding stage. This is still not the final sanding for the project but it flattened the shells and the overlay.

One small problem I discovered was a small depression in the surface of one of the shell pieces. You could feel it if you ran your fingers over the shell. I'm not sure how it came about. There could have been a small void in the shell , which got exposed when I sanded down. The shell is made of thin layers or flakes and a piece could have lifted off at some point. At the advice of John Hamlett on mandolincafe.com, I was able to fix the shell by dropping a tiny amount of CA (superglue) onto the shell surface. It dried clear as glass and I was able to sand it down again to a flat surface.

That's it. The inlay is done and I'm very happy with the design and result as well.

Moving on to fitting the neck - the next chapter in this adventure

Upgraded the tuners

2008-02-23T19:14:00.005-05:00

Once I started fitting the tuners into the headstock, I realized they turned too roughly. I suppose at that price point, I could not expect better tuners. On the other hand, this is my scratch mandolin for learning and so investing a lot in tuners would not make sense for me either. I decided to go for a slight upgrade into tuners made by Ping. The buttons are integrated and chrome plated as the rest of the tuner assembly. When the package arrived, I was pleasantly surprised just how much smoother the tuners turned. I have a photo here of the original tuners and the new Ping ones, side by side. Original on the left. New ones on the right. You couldn't tell much by looking at the photo but this upgrade is recommended, not only by myself but by most who have built this kit.

I completed filing open the tuner holes through the new ebony plate and did a dry fit of the tuners. Everything seems to fit well. The photo shows the new tuners in. No screws yet. That will come once the whole instrument is assembled.

By the way - the ebony is not pitch black but has some dark brown streaks through it. Many builders dye the ebony so that it's completely flat black but I'm not sure I want to do it. Right now I like the variations in the wood. It adds some character.

Headstock overlay work

2008-01-01T18:21:00.000-05:00

I focused on the new headstock overlay in the past couple of days. The first thing I did was trim all the ebony waste around the headstock to get it nice and flush with the headstock. It wasn't hard work but I did learn several things in the process:

Ebony is brittle. My plan was to use a coping saw to cut the ebony plate as close to the headstock as possible. I don't have any power tools other than a Dremel and a hand drill so I resort to various hand tools. I started sawing and very quickly felt that the ebony grain was pulling hard on the saw and I wasn't in full control of the saw. Small pieces of ebony started splitting off - probably because I was trying to change direction slightly with the saw. OK - Plan B. I switched to a fine back saw and cut off the most obvious large waste pieces with straight cuts. Still - I needed to get close to the headstock. I wish I had some half-round woodworking rasps but I don't. I took a chance and tried to use the Dremel tool with a sanding wheel. Surprise - it very easily and smoothly removed the remaining ebony until I was almost at the wood-line. The remainder of the way was smoothed with a combination of sandpaper wrapped around a dowel and a scraper. You can see the result in the first photo - nice and flush.
Need better fret saw blades. I think I may have been able to trim the wood with the fret saw if I had a narrower and finer fret saw blade. The Dremel trick worked ok but it generated a TON of ebony dust. I was wearing a mask but still, the cleanup was significant afterwords, especially considering that I'm working on my....dining-room table....
Good sandpaper makes a difference. Just around the holiday, Woodcraft had free shipping on everything. I used the opportunity to experiment with some new sand paper. I had been using generic paper from Home Depot or Lowes, or even Sears. I ordered an assortment of Norton 3X paper and got to try them this past weekend. I'm impressed! They cut so much better, don't clog up as much, last longer, and the backing paper does not fall apart after folding it multiple times in different directions. It's almost fabric-like although obviously not made of fabric. I'm sold.
Learn to improvise without a stationary sander. The end of the headstock was not square to the face plate. I supposed, if I had a stationary disk sander, I would slide the headstock up to it and square it in about 15 seconds. But I don't. I thought of using a block plane but the edge is only 1/2" and I was worried I would not be able to hold the plane securely. Here is what did work - I had some small machined squared pieces of wood that I used for block sanders and such. I glued some sandpaper to one of the blocks and stood it up on it's end, as it if was a disk sander. I clamped the headstock to the table and then started running the sanding block along the edge that needed treatment. It was very similar to a shooting board. And it worked very well.

Drilling holes for the tuners.

The IV kit comes with the tuner holes pre-drilled. This is fine except that now I've covered the holes with the new face plate and the holes needed to be re-opened. One odd thing is that the pre-drilled holes are tapered and not straight. It's unclear to me why this is the case. The holes are smaller in the back of the headstock and larger in the front. I decided to use the hand drill to start some holes in the ebony. I clamped the headstock with the ebony plate down on a piece of sacrificial wood so that I can drill through and minimize the tear-out. I was now paranoid about splitting the face plate after seeing how brittle it is. Also - since my drill bit would be passing in the pre-drilled holes, I was worried about my unsteady hand and the prospect of the drill jerking and putting a gouge in the wood. I took a plastic pen and cut off a piece of the tubing to use as a protective shield. You can see it in the second photo. This worked very well and the holed remained untouched. I used a narrow drill bit and managed to get through without breaking the ebony.

Enlarging the holes was more work than I had anticipated. I tried to use a larger drill bit but that was too much and I could hear the ebony crunching rather than giving in when the bit twisted in it. Maybe if I was running the drill at high speed and coming in gently, I would be able to do it better but not with my hand drill. I ended up clamping the headstock vertically in my vice and enlarging the holes slowly with narrow files and also with sandpaper wrapped around files. I'm half way done , as you can see in the last photo, but I completed one set of tuner holes and dry fit the bushings and the tuners.

I have a long way to go but I like it already.

Headstock design

2007-12-16T20:08:00.001-05:00

I'm going to take a break from the binding work. The binding problems took a lot of time and mental energy and I could use a change of focus. Working on the aesthetics is a good creative outlet. I've been playing with headstock design for a little while. I make up a bunch of paper headstock templates, soliciting ideas from those around me. We even recruited the kids to take headstock blanks and draw in their ideas. Since I want to cut my own shell and do all the inlay work myself, I want a simple, yet elegant design. This weekend I was looking at some earrings that Sarah had bought as a gift to a relative, and was stuck by an art-deco'ish idea. I replicated the basic shape in a drawing program and printed out various samples to play with. Sarah came up with an interesting arrangement and so far this is my favorite. You can see it in the mock-up photo. It consists of three geometric figures, repeated in a fan-like arrangement, over a single small square "dot". Each figure is made up of two puzzle-like pieces, one of abalone and one of mop.

I spent some time cutting out one figure and working on matching the mop with the abalone pieces. I like the design even better, now that I can see it in real shell pieces.

Challenge: How to get the best fit of two pieces of shell. Although I'm generally pleased with my pieces, they do not match perfectly when put together. I've read about a technique for getting a good match. The idea is that you take both shell pieces and glue them back to back with the full pattern glued on top. By cutting both pieces of shell at once, you have (in theory) a superior match between the pieces. I have prepared a sample like this will be cutting it next. You can see it in the photo, on top of the shell cutting apparatus.

The second photo shows a black paper mock up of the headstock, with the design arranged. some of the pieces are still in white paper but the central piece is the which I cut today, as well as a small dot. The shell looks beautiful but will be much more striking once it's polished. These are still all practice pieces before trying to go for the real thing.

The plan now is to cut one more figure and then start practicing routing a cavity for the inlay on some scrap piece.

Back to work

2007-11-22T19:55:00.002-05:00

It's been a long time since my last posting, indicative of the severe lack of time during the past 6 months. Restored sanity in my (work) life is allowing me to resume work on my mandolin.

It feels great!!

3D Sander

Someone on mandolincafe alerted us to a sale on the 3D sander at Sears. I'd been looking at it for some time as it seemed useful for sanding curved surfaces, but have not pulled the trigger. But at $8.99 (instead of $30) how can I go wrong? This is not a high-power sander, but it does have the unique advantage of having three independently-adjusting "heads", kind of like an electric shaver. The floating heads have Velcro on them and you can get small circular sandpaper rings at various grit levels. In addition, you can pull off one or two of the heads and use a single head for getting into tighter places. I think it can be useful for the top and bottom of the mandolin and getting into places like the recurve area.

Top Binding

The top binding has been a struggle. I ended up ripping off the second half of the top binding because it had pulled away in the tight curved area near the neck. My efforts to soften the binding material with hot water (in a pan) were only partly successful. It took a while to clean up the binding channel and prepare it for a second attempt. I knew that hot water was good enough to pre-bend the plastic material but the flat pan that I used cooled off too fast. This time around I poured boiling water into a tall and narrow flower vase and it did the trick! I could dip the binding in the water and watch it "relax" after about 5-10 seconds. It was easy to pull it out and quickly mould it to the mandolin. I wanted to achieve a close fit so that the binding would not spring back when glued.

The second thing that I did differently was glue the binding about 3-4 inches at a time. I was worried about how I would be able to get the glue in to the narrow area where the already-cured and the new parts of the binding met, but decided to try it anyway. It worked much better than I had expected, allowing me to pay close attention to each part with no rushing. A GOOD thing.

The picture shows the first, completed, binding piece on the left. It's been scraped down flush with the top. On the right side is the new binding, with the "bandages" removed. It's ticking up from the top but that's ok. It will end up flush just like the other one.

New Veneer

I had ordered two quality face plates to replace the paper-thin one that came already-installed on the peg head. I took a while to decide between the rosewood and the ebony but I decided to go with the ebony plate for this mandolin. Preparing to glue the plate on the headstock, I cut out a notch to reveal the access channel to the truss rod. This was easy to cut with a small dovetail saw. A firm blow on a 1/4" chisel left a clean opening, which you can see in the photo. hey - I had to find a use to the wooden mallet I had bought. Very satisfying :) It's not important to have the cut looking perfect since it will be hidden by the truss-rod cover.

I also decided not to use the plastic nut that came with the kit. For a very small price, I got a nice bone blank and will be able to custom fit it in. I used the blank to space the ebony plate away from the fingerboard, and glued on the plate. Trying to clamp the plate on, I found it fishing around too much. Next time I will consider installing two small wooden locating pins to help with the position. As you can see from the photo, one can never have too many clamps. I used as many clamps as I could to ensure a solid fit. Once it dries, I will have to cut out the tuning peg holes. They are already drilled in the headstock but not in the face plate. Any additional shaping of the headstock will be done at one shot, including the face plate to ensure a nice finish.

re-working the binding

2007-06-03T21:29:00.001-04:00

The first attempt at binding the top did not go too well. When I removed the "bandages", I found out that some of the binding pulled away from the body and the seam where the binding meets the sides was not clean either. I pulled off the binding and went about making corrections to my method.

The first thing I did was use hot water to pre-bend the ABS binding to be almost perfectly aligned with the body. The idea was to remove most of the resistance that the plastic has and require much less force to hold it against the body as the glue sets.

The second thing I did was more detailed cleaning of the routed binding area, to improve the seam with the sides.

The result - a much better fit. I am happy with how tight the binding hugs the top. The interface between the wood and the binding, on the side, could still be better but I will keep this one and plan to improve as I put additional binding on.

I scraped the binding flush against the top and sanded the side wood to meet the binding.

By the way - the clamp that you see in the picture has nothing to do with the binding. The kit came with one of the sides not completely glued to the neck block. I just glued it back and it's being held tight to dry with a cam clamp.

Binding the top

2007-04-08T18:17:00.000-04:00

The kit came with white binding material for the top only. Since I wanted to bind the back as well, I needed additional binding. The white binding was ok but I wanted to try something a little more interesting and so I bought some striped (wbwb) abs binding from LMII. This binding is thicker than the one that came with the kit and so, the routed area in the top of the mandolin would have to be deepened. I've been thinking about this operation for a while. If not done well, the results would be very evident. An uneven ledge would show gaps. If the ledge is too shallow, then sanding/scraping the binding would show up as uneven stripes. Better make the groove a little deeper than needed but not too deep. The sides can be sanded down a bit to meet the binding.

Since the IV kit comes with the sides already attached to the top, it's not easy to clamp the mandolin in various positions. I needed to hold it with side pointing up so that I can run the router around the edge. In order not to break the (unsupported) side piece, I used a piece of heavy close-cell foam, borrowed from my kayak outfitting. You can see it in the photo. This kind of foam is stiff enough and cuts very well using a saw.

I used the Dremel tool with the binding routing attachment, as I did on my straight test piece in the previous posting. There were two potential problems with this tool. First - it's not easy to hold it straight and steady. Small movements can cause the Dremel to dig deeper into the top. It turns out that I could not hold it as steady as I wanted and wound up spending a lot of time fixing an uneven ledge. It's not as nice as I was hoping but - hey - it's my first time. Second - I didn't want to damage the nice straight routed edge on the sides. I decided to set the router to a shorter distance than the actual ledge. This kept the blade away from the "factory" edge. The price was much extra work cleaning out the remaining un-carved piece inside the routed area. I think this was worth the effort. The photo shows a section of the groove after enlarging it. You can see how much deeper I need it to be, compared with the original. A little while ago I bought a cheap set of needle files, in various shapes. They came in very handy today when I needed to clean up the inside of the routed groove.

One the enlarged ledge was clean, I had to figure out how to bend the binding into the tight curve near the neck joint. The binding is somewhat flexible but could not be bent to the small radius that's called for near the neck. I tried using a hair drier to heat up the binding but could not get enough focused heat. I then tried hot water and got much better results. Pre-bending the binding would mean a lot less stress when gluing/taping it on.

Although the binding pieces are long enough to do the entire top in one shot, I decided to do it with two pieces, joining at the tail block. That joint will be covered by the tail piece and so it will be invisible. Binding the top with two pieces has the advantage of pre-bending each side and gluing each piece starting with the tight curves.

The gluing went fast and with no issues. I used lots of painters' blue masking tape - the "delicate" type - to keep the binding attached while curing. Instead of gluing both pieces, I started with one and will see how it works and trims before putting effort into the second piece.

Experimenting with binding

2007-03-17T15:39:00.000-04:00

I bought some plastic binding from LMII. The idea is to bind the top and back of the mandolin with a WBWB pattern. The kit came with a white piece of binding, long enough only for the top, some some changes will have to be made. First, the top binding channel (that exits already in the kit) will need be deepened to accept the thicker new binding. Then a channel will have to be cut from scratch on the back, after it's assembled. In the meantime, I decided to experiment a bit with routing, gluing, and trimming this binding.

For cutting a channel, I'm trying to use the StewMac Dremel attachment with routing bit. People have conflicting views on it but I thought I'd give it a try. I can see that one needs a very steady hand to prevent variation in the channel depth. It doesn't take much to rock the router across the edge of the instrument and to cut deeper. I practiced for a while on straight edges of scrap wood, until the channel began to get cleaner and more even.

For gluing, I am using Weld-on 1874 cement. This was recommended by LMII, when I bought the binding. The glue is clear and fairly thin. I applied some to the empty channel and let it sit for a bit to dry. I then applied glue to the binding strip and pressed it into the channel, securing it with strips of masking tape. I don't have the blue painters tape yet so I'm using "standard" office masking tape. It's ok for the scrap piece, which is made of Maple. I'll have to get some blue tape when I deal with the spruce so avoid lifting grain when I remove it. The binding glued on very well and sees to be holding strong.

After a couple of hours I was able to scrape the edge down to the wood. This went very well, using my wood scraper, and left a perfectly clear WBWB pattern against the wood. On the side, the channel was a bit deeper than the binding (on purpose) and I used a sanding block to bring the side down to meet the binding face. I was worried about having sandpaper scratches on the plastic but it turned out to sand very nicely and left a smooth non-glossy face. I'm very pleased with the result.

Carving x braces

2007-03-10T19:54:00.000-05:00

I finally got around to carving the braces today. It's been too long between work sessions but I'm grateful for the little time I could put into it today. I understood the main idea of tapering the braces towards the outside of the mandolin and feathering the ends to blend with the top wood. Tool-wise I tried using one of my chisels but gave up on it since it was too long and I could not get it inside the body. Another point against the pre-assembled top/sides unit. Since I don't have a thumb plane (yet) I resorted to a chisel-end craft knife. The handle is short and stubby and fits well in my hand. I sharpened the knife before using it and got fairly decent control over the size of the chips. The big mystery is just how much material to remove? There is no general guideline that I could find. I listened for voices in my head to give me spiritual guidance appropriate for the task but alas - no voices :) I could carve it down to nothing. No clue. What I did was create an even taper from the cross towards the ends and knocked the edges down, sanding it all nice and smooth. At this point, unless I get some new information, I plan to leave it as is and continue.

Feels good to make wood curls again

Removing the headstock veneer

2007-01-01T17:39:00.000-05:00

It's been a long while since I worked on my mandolin. Too long. I finally had some today and decided to start working on the headstock. The kit comes with an already-applied veneer. It's very thin. While it's perfectly ok for what it is, I want a more substantial and more interesting veneer.

To remove the veneer. I used a clothing iron and spent time steaming it off. I used a rag in between, to protect the iron. It did not come off easily. I had to scrape some of it off as the glue did not want to give, even with the heat and steam. You can get an idea of how thin the original veneer is, from the picture.

It did eventually release but left a big glue mess to deal with. I tried to sand it off with a low-grit paper (50-80) but it was too gummy and didn't want to release. I used a paint scraper to remove the bulk of it and then applied some mineral spirits.

The solvent method worked the best and the headsotck cleaned up nicely. I then sanded it down by hand with a sanding block. It's looking pretty good for gluing up a new veneer.

Of course - now I need to decide which veneer to use. I have both a nice piece ebony and a rosewood veneer that I had bought from StewMac.

I'll settle on the design first.

I also spent some time today practicing sharpening and honing my chisels. I'm using the ScarySharp method and found it very easy for flattening the back of the chisels. Nice polished mirror finish. However, I could not hold the chisel steady enough when working on the bevel side. I broke down and ordered a honing guide to get me through this step.

braces

2006-11-11T19:34:00.000-05:00

Master luthier John Hamlett was nice enough to give me suggested steps for fitting x braces. I could find no directions anywhere and had various questions. Today I followed John's suggestions and I think it worked really well. Although I had bought some new brace stock, it turned out that I could re-use the tone bars that came with the kit.

I designed the X such that the bridge will wind up sitting over the braces and be located about 1 inch below the crossing point. Fitting was the most time-consuming part. I used tracing or "transfer" paper (from a craft store) and used the "dentist method" of rubbing the item to be fitted and finding the high spots. I then used a scraper and sandpaper to make the adjustments.

It took a while but this is an important step so I took my time. After fitting the two braces independently, I cut the notches and tried to get them such that the two pieces of wood would meet exactly at the same time as the wood got flush with the top of the mandolin. I used a set of jeweler's files to adjust and clean up the notches - Very useful tools for this!

Finally I glued the braces to the top with Titebond and secured them with as many clamps as I could fit.

The next step will likely be carving the braces.

Like many others, I am constantly amazed by the generosity of people on the Internet and their willingness to help and offer advice.

Cutting the hole

2006-10-28T23:19:00.000-04:00

I finally did it. After much debate, I decided to place the oval hole in the higher position (see an earlier posting) and cut the hole today. I spent a good hour sanding the top up to a 150 grit level, to minimize the heavy sanding after the hole would be cut. I then printed out the oval shape and transferred it onto the mandolin. Ideally the hole would be cut on a scrawl saw but I don't have one. Actually, with this kit, a scrawl saw would not help either because the sides come attached to the top - a source of various frustrations. A deep throat fret saw would be very good too, but I don't have one...yet...;) Therefore I had to use my coping saw and cut it freehand. I had bought some new blades a few weeks ago at Lowes. There were not many options - just one pack. The blades are about 1/8" wide and this turned out to be less than ideal. As narrow as 1/8" seems (when I was at the shop), cutting a tight corner is not easy. I really needed a fine fret saw blade.
Still, I drilled a hole in the oval pattern, and threaded the saw blade through it. The cutting was hard not only because of the blade width but also because I had to keep on twisting the blade in the coping saw frame. The saw "throat" was not large to go all around the instrument so instead I had to keep rotating the blade in the frame. At least the frame allowed for this. I worked slowly, trying to stay away from the line and leave room to clean up.

The hole was cut and left a jagged edge all around.

Cleaning up the hole turned out to be more fun and rewarding than I had imagined. I used the Dremel tool with the sanding drum, working very carefully and "caressing" the edge of the hole until I reached the line, leaving behind a smooth trace. The top of the mandolin has a definite thickness where the hole is cut and therefore, the hole needs to be cut and finished in 90 degrees to the top. I don't have a clear method to achieve that yet.

My plan is to bind the hole using the same binding that I would use for the rest of the instrument.

Learning how to cut shell

2006-10-19T00:24:00.000-04:00

It's time to learn how to cut shell and inlay. I had bought some mop and abalone shell pieces from Andy dePaule a while back, and finally got to it tonight. I set up the cutting jig (stewmac) and drew two simple shapes on some tracing paper. I then glued the tracing paper onto mop blanks, using white glue and let them dry for half an hour. Cutting the shell is more enjoyable than I had thought. I like the way the shell reacts to the blade and the cutting was pretty smooth in general. Of course, as expected, I broke a piece of the first design, when cornering too hard. A piece of the shell flew across the room with a 'ping' sound. I also broke a blade on my first piece. No surprise there either. It's expected in the early stages of learning, from what I've read. The second piece went much better. I switched to a finer blade and was able to complete it with both the shell and the blade intact. I put the cut shell under hot water and removed the paper.

The shell dust though is a little bothersome, as it's not good to breath. I used a dust mask and cleaned the area afterwards, but I'm looking for a better place, and set up, for controlling the shell dust. The other thing to consider is getting a head-band magnifier. I'm sure I can get my cuts to be more precise under magnification.

Next time I plan on touching up the cut shell with some files and routing a cavity for it.

Where does the hole go?

2006-10-02T21:56:00.000-04:00

The question of the week is: Where should the hole be located? On one hand, I am trying to build an oval-hole mandolin - similar to ones that were produced by Gibson early on in the 20th century. On the other hand, this kit has a neck that attaches at the 15th fret and not the 12th, as is the case with the traditional mandolins. The more I thought about it, the more I saw (at least) two possibilities for the hole location.
Option #1: Locate the hole 3.25" away from the 12th fret, as is the case in the old mandolins.
This option retains the same bridge-to-hole-to-nut spacing as in the old mandolins. However, it forces the hole
to a higher location on the body

Option #2: Locate the hole 3.25" away from where the neck joins the body, as is the case in the old mandolins.
This option retains the same hole location as on the old mandolins, but changes the distance from the bridge to
the hole and from the hole to the nut.

The two photos here show the possible locations. I've been soliciting opinions on this from mandolincafe members. Some information is starting to come in but I'd like to get some more before making my final decision. Right now, I am leaning towards option #1. I've seen at least one example of a hybrid F4 mandolin with an F5 neck and the hole was located as in Option #1. However, I also saw an example of another IV kit where the hole was located as in option #2.

By the way - the photos show the neck in place but it's not attached yet. I just positioned it there to get a sense of the proportions.

In addition to thinking about the hole location, I'm starting to design the headstock. I have several design ideas already. It's clear that the thin veneer on the existing headstock is coming off and a new thicker veneer will be attached. I bought both ebony and rosewood veneers and will pick one depending on the final design and color choices.

Graduation

2006-10-02T21:39:00.000-04:00

I completed adjusting the graduation of the top. The process was less than ideal. For starters, the kit came with the top carved thinner the center (and other places) than what Siminoff recommends. The best I could do was try to even it out rather than shoot for specific thickness. I did spend some time on the recurve and I'm fairly satisfied with that part. In addition to taking some point measurements, I also put it up close to a strong light and tried to get an even "color" through the light. This may not be a very scientific way to go, but it gives an overall picture of relative thickness. The hardest part was using scrapers inside the top piece. What would have been a more straight-forward operation, wound up to be awkward because the sides are attached. There is very little room to move around with scrapers. Also, holding down the top assembly was challenging. Here is a photo of one way I was using to secure the top to the work area. I still need to do final sanding and smoothing of the inside, prepping for the braces, before I cut the hole... The hole deserves a posting of it's own

First measurements

2006-09-04T19:20:00.000-04:00

I used my new thickness gauge today and measured the top, before starting any graduating. I am using the (new) Siminoff book as a general reference for building the instrument. Therefore, I took the same measurements that Siminoff illustrates on the blueprints. I expected them to be off and then make adjustments. However, the mandolin top is thinner, in general, then the Siminoff spec. I've heard the same from other IV kit builders and so I wasn't quite surprised. However, I am paying attention to the min thickness, which is in the recurve area. The min thickness of the top piece is measuring around .12", before any carving or sanding. Siminoff says .12 is good for wood that's 14 grain lines inch or more. He also says that you can go down to .110 if the wood has more than 14 lines/inch. The top of my mandolin has uneven grain lines, being most sparse at the center and getting denser as you get to the edges. In the min area, the line density is close to 18/inch. I suppose that that's good if I'm going to end up with or even less after final shaping and sanding.

Since there is no way for me to match the Siminoff spec, the best I can do is try to make the thickness as even as I can around the plate, so that it vibrates evenly all the way around, and put in a small recurve close to the edge.

Note: Since the gauge has round surfaces (where it meets the mandolin plate) and since the plate itself is curved, you can get various readings depending on how the plate is angled. The correct (and most sonsistent) measurement is the one that gives you the min reading.

Thickness gauge

2006-09-02T16:09:00.000-04:00

Today I completed my thickness gauge. I made the initial frame out of MDF and found out that it had way too much flex in it. I made a second pass, adding steel plates (very inexpensive at HD and Lowes) and bolts. It made a huge difference. So far I don't see a need for a base, since my vise is right next to me whenever I work and it holds the gauge securely.

Did I mention that I really don't like MDF for anything other than large, simple plates? Any kind of working, shaping, drilling, breaks it down into dust - which is basically what it's made of.

The next two important actions are graduating the top and cutting the oval hole. I am waiting on a friend (Karen) to trace one or two mandolins for me so that I can have some real hole measurements and locations to use as reference points.

Sharp scraper

2006-08-27T15:02:00.000-04:00

I spent time today sharpening and burnishing my scrapers. What a difference it made! Long transparent, tissue-thin ribbons of wood came rolling from under the scraper as I put it to the maple back. I used the scraper to remove all of the larger tool marks off both sides of the back piece. Very enjoyable work. I then put it to use on the spruce top and realized what others had been saying. Spruce is a whole other animal. What it means is that it resists scraping and rips easily. I had to work carefully but eventually switched to sandpaper. In fact, I had to use sandpaper a lot today, after noticing that (even after scraping) the back piece remained with waves (high and low spots) in the wood. The waves were long enough so that the scraper just followed them, rather then "plane" them down. What did the trick was 80 grit paper on a small wood block. I think the block is essential to make sure the paper contacts only the high spots. I'm not quite done with the rough paper process, but made a lot of progress. Good lighting is important for seeing the small high spots in the wood.

I also took some preliminary plate thickness measurements today and compared them to the Siminoff book. In general, the center point of the plates (thickest part) is thinner on the IV kit, compared with Siminoff. The min areas are thicker though and I am relieves since it looks like there is room to build more of a recurve.

Next on the agenda is to graduate the top and back and shape the recurve, before dealing with the cutting of the hole.

A new back arrived

2006-08-06T18:17:00.000-04:00

The new back piece arrived this weekend from IVC, and.....it's a better fit!! I mean, it's just wide enough so that I don't have to worry about pushing the side pieces in when gluing it in. I am very happy with the level of customer service I received and will be happy to deal with them in the future. As a side bonus, the wood is nicer than the original back that came with the kit. I can't tell how much figure is in the wood but the color is more even across the back.

The next thing is to build a thickness gauge. I went to Lowes today and bought the hardware needed. I have the dial indicator already and some wood. All I need is to find some time to put it together. Once I measure the top and back, I can decide where I need/want to make adjustments.

scraper

2006-07-31T23:30:00.000-04:00

I had ordered a set of 3 scrapers and just got to try them out tonight on some scrap wood. I used a mill file to sharpen the edge and then burnished them with a hard drill bit, skipping the honing phase because I don't have sharpening stones. The whole burnishing action is a real feel thing and I can see how it would get better with experience. I managed to get a burr but probably not aggressive enough. Some of the scraping yielded only dust but I did get a good bit of curls generated as well. It's far from drawing long even wood curls, but it's a start. Next time, I'll try to use some fine sand paper on a glass plate to hone the face and edge and smooth out the file mark.

Watch your back

2006-07-31T12:43:00.000-04:00

I've had some concerns about the back piece fitting properly. It seemed a little too small at the widest points of the instrument. Several people on the Cafe looked at closeup photos that I posted and thought that it would work out ok especially if I were to bind the back and/or push the sides in slightly. I also received advice to let the instrument sit for a little while and acclimate. The wood may move some. I was ready to take all the advice. However, Ken Wise (from IVC) approached me and offered to send out a second back so that I can compare and send back the lesser of the two. How is that for service?

In the meantime, I need to learn how to sharpen/hone/burnish the scrapers that arrived.

The IV is now connected

2006-07-27T00:08:00.000-04:00

My first kit is here. It's known as the IV kit since it's sold by International Violin Company. I'm very impressed with their service. It got shipped the same day as the order and arrived two days later.

I am going to use this kit as my "scratch pad" for learning as much as I can about building. To that end, I've decided to get a version of the kit that has no holes cut in the top. My plan is to turn it into an oval hole mandolin. As such, the bracing will change from the way the kit was designed. I'll probably try to do an X bracing pattern.

This IV kit was designed to become an f-hole mandolin. This means that the neck is made to connect to the top at the 15th fret. Oval hole mandolins usually have the neck connect at the 12th fret. I would like to use this "problem" as an opportunity to learn how to design/carve/fit a new neck. That's an exciting prospect for the project. If I run into problems, I can always just use the neck that came with the kit and see how it sounds.

Other things I'm thinking of changing include - different binding, binding of the back, headstock inlay, oval-hole rosette, and maybe even (heavens!) installing an internal pickup with an end jack.

Tool-wise: still to come is a set of scrapers, spool clamps, as well as tools and supplies to cut inlay pearl and route the cavities. I ordered the StewMac Dremel router base, as well as a saw/jig/blower kit and a book. In addition, I had a nice chat with Andy DePaule (inlay shell supplier) and he is sending me some inexpensive mop and abalone pieces to practice cutting.

Setting up shop

2006-07-23T23:05:00.000-04:00

The most immediate challenge in doing lutherie (or any woodwork) at my place, is the lack of workshop space. The only space with day light, and non-carpeted floors, is my dining room. It's a great space to be, since I can look out over the water and watch the boats as I work. Of course, since this is not a dedicated shop, I can't have a permanent setup. I will have to work on the dining table, and break down and clean up after most work sessions. I also don't have room for any machines, other than some hand-held ones. On the other hand, this is an interesting opportunity to see what can be done with hand tools. I am in the process of buying a few, and learning how to work with wood. It's been a very long time since I've done true wood craft and I'm eager to learn again.

Today I cut up a sheet of MDF board to be a work surface and protect my dining table. I can clamp it to my table and then remove it afterwards. I also set up the parrot vise for work. The first thing I did was mount the vise on a piece of MDF so that I can clamp it to my table when I need it. The second thing was to make some protective jaws for the vise so that it doesn't mar the wood. I made a cardboard template of the jaws and then transferred the shape to some 1/4" aspen that I had. After cutting it, I covered one side with some 1/8" neoprene that I had left over from kayak outfitting. I used contact cement to bond it to the wood piece. On the back side of the protective jaws, I put a business-size magnetic card that comes with a peel-off side for attaching it. The magnet will help keep the protective pads attached to the jaws.

2006-07-23T23:00:00.000-04:00

This is me. The photo was taken recently at a CBOM get together in Phili. I'm playing a beautiful custom-made octave mandolin that belongs to Karen (Otter), made by Brian Dean. Inspiring work!