Tuesday, March 22, 2011


Well, it has been a long time. And of course I finished the instrument almost a year ago, but haven't gotten around to posting anything about it here. I have to say I am super happy with the way it came out, especially given my inexperience with building instruments. My only real disappointments have to do with the fretboard - I failed to drill for the position markers accurately enough (they look ragged to me) and the fretting went well but not perfectly. Specifically I didn't dress the ends of the frets as well as I could have. Inexperience, I guess - fretting was the hardest part of the entire exercise for me. The rest was basically woodworking, and I have experience related to that. But fretting was a new animal. They are level and fully seated but the ends could have been dressed better. Nonetheless everyone who has seen it is impressed with the final product.

I'll post photos later.

Now, a good friend asked if I'd build him a banjo. So that's the next project. And, to take advantage of economies of scale (and the building of various jigs) I plan to build as many as five of them at one time. More information to come - I'm in the planning stage right now - but the first step will be to build a table for my existing lathe, with a purpose-built end lathe at the far end for turning the rims. My next post will be on that project, scheduled to commence on or around April 1st (since the shop reorganization - read cleanout - is underway).

For what it's worth, not counting the cost of the kit (which was a gift) I spent about $500 to build the instrument. However, almost all of this was for tools that I will use on projects for years to come. I figure about $60 in one time costs - glue, epoxy, etc. almost $20 for strings. If I'd have improvised rather than buying fancy tools for some tasks I could have kept the overall cost very low, though the nutmaking kit was well worth the cost, as were the fretting files.

And I got an instrument I'll play for the rest of my life for that trouble. And enjoyed every minute of the task.

Banjos, here we go! (I don't play the banjo, either!)

Wednesday, October 21, 2009

Fretwork and fingerboard glue-up

I trimmed the frets to length and spent sometime filing them to length. Following the instructions I also put a slight angle on the ends of the frets (the instructions suggested about 60 degrees, and I agree with that in concept based upon my playing experience, so I tried to make the angle about that). I'm glad that I bought the Stew-Mac fretting essentials kit because it came with several useful and rare files and then fret nippers, which really do a great job of cutting the frets flush. The book that came with it didn't help me much, though, as it seems primarily oriented to re-fretting work. Here are some photos of trimming the frets and the results of the filing.

Note: photo enhanced for contrast

After doing that, which took only about half an hour somehow, I decided to glue the fretboard on. I did this with Titebond and the rubber band strip supplied with the kit. It turned out to be easy, too.

Next step is sanding the neck and installing the tuning machines.

Tuesday, August 25, 2009

Fretting and body work

So I finally got back to work yesterday and accomplished a bunch. The body was mostly complete, except for finishing, but I needed to trim the top and back to fit the sides exactly. In many places this was already done, but yesterday I finished this work. I started by sharpening my block plane’s blade to pretty much lethal sharpness. I then used the plane to remove most of the wood. You can’t really remove the entire overhang with the plane because at some point you’ll start removing material from the sides with the plane, too. After using the plane to do most of the bulk work I used a sanding block, made from a piece of 3/4 “ plywood, wrapped with 80-grit self-adhesive sandpaper to remove the remaining overhang. I sanded the top and back edges until they were flush and there were uniform sanding marks on the sides as well. (As recommended by the instructions I sanded very little at the neck joint to minimize distortion of the shape of the neck-to-body joint, since we want that to be tight.) Having sanded the top and back flush, I wrapped some 150-grit around the sanding block and did some cleanup on the sanding marks.

Here a problem presents itself. I fitted the neck just to check things out and it turns out that the body is a bit too thick – the fretboard rides out onto the body at the end of the neck, but the body is thicker than the neck at this joint and the fretboard will not fit. A couple of pictures will probably make this clearer.

See the “hump” at the neck-to-body joint? The fretboard will not work with that hump. I must admit that I’ve been concerned about this for a few weeks, but today I decided to just fix it. So I marked out the area that the fretboard is expected to cover on the top with a pencil, and made a mark on the edge where the neck meets the side, and went to work with a chisel thinning down the top in this area. Here you can see this work underway:

I have to assume that if I had done more sanding during the step below where I put the curvature into the top I would not have had this problem. As it is I hope that the neck angle works out (I think it will) and that thinning the top slightly in this area won’t make the top unstable (I think it won’t). Hopefully I can disguise this in the finishing, too, but that remains to be seen.

I still had some time (and energy, and guts) left after that bit of work, so I decided to tackle the start of what might be the hardest part of the project - fretting the fingerboard. The instructions tell you to do this before gluing them together, and though at first I wondered about this, I get it now. The hammering is much easier to do when you can lay the fingerboard flat on the bench rather than having to support the neck's contours sufficiently. The supplier helpfully left some extra fretslots in the cutoff piece of fingerboard for practice. I already did one months back, but as a refresher I did another. Here is a photo of the new one (I'm pointing to it):

By the way, I'd recommend buying the fretting kit from Stew-Mac - I used a cobbled together set of tools and find myself needing to order from them anyway to finish. Here are my tools, and a piece of the fretwire as delivered:

I bought the hammer from Harbor Freight and the dikes are my wife's from her stained glass kit (sorry, Babe, I'll give them back!).

Turns out that seating the frets is relatively straightforward and it only took me about half an hour. Here are the results, and a detail of a few of them (I know, I really didn't drill the fretboard dots very well!):

And here is a summary of everything today:

Thursday, April 16, 2009

It's been a while, I know. I have been busy. But I got laid off about a month ago, and I don't start work again for another month. So I hope to finish the mandolin before returning to work. I got the tuners and tailpiece from Stew-Mac this week. I am out of town this weekend but will return to the project in force next week - an hour a day is my goal.

Also, found another blog just today from a much more ambitious guy than I am who is building a carved arch top mandolin. His site is very nice, and his descriptions are excellent. He's got guts - it's his first instrument, too, but his work is really wonderful. Check him out here.

Sunday, November 30, 2008

Body and frets

Some progress! I was able to spend about an hour and a half in the shop yesterday and I made some progress (but took no photos, more's the pity, though I suspect that a post without photos will be well received by all three of the people who read this...).

The progress I made is principally on the top and back. Though I had already taken a block plane and trimmed the top and back as close as I dared to the sides while waiting for charcoal to be ready for some hamburgers, I still had plenty of work to do on them. I took my self-adhesive strip sandpaper, 80 grit, and stuck a length of it to the sanding stick supplied with the kit. I them busied myself sanding the top and back at their edges so that they no longer overhang the sides. This took less time than I thought it would - that 80 grit is aggressive! - but I was forced to stop when I got very close for fear of damaging the sides themselves with the abrasive. I will get myself some 120 and 240 grit self-adhesive stuff and finish the job this week.

I also bought a hammer from Harbor Freight that has a plastic head and a resin head to use in the fretting (the non-metallic heads are not hard enough to damage the fretwire). I cut myself a length of the extra fretwire provided with the kit for practice and did a quick test-fretting experiment on the extra length of fingerboard also thoughtfully provided for this purpose. It turned out to be much easier than I feared to get what appears to be a nicely installed fret. Put the wire in the groove, sharp tap at each end, and then sharp taps across the width of the fingerboard (I think three across the width after seating the ends). Of course it remains to be seen if I can do that successfully 15 times, and then get them level and smooth and properly dressed (the part that really makes me nervous, truth be told) but it was heartening nonetheless.

Sunday, October 12, 2008

Body fully glued up

And here are the results of the glueups for the body. Still have to trim the top and sides, but this is well on its way.

Of course, I also still have to fret the fingerboard. And then there's all that finishing...

Thursday, October 9, 2008

Top and back

Over the past two days I have glued the top and back onto the mandolin. This was much simpler than I expected (as, in fact, most of the project has been). First, though, I made some spool clamps. These are expensive - about $20 for a set of six from Stew-Mac - but simple. Basically they consist of a threaded rod with a wingnut for tightening and two short (about 3/4") lengths of dowel. To do it right you have to pad the dowel sections with cork. Since this is so straightforward, and since I happen to have a full woodshop with a chop saw and a drill press, I made my own and saved about $60. They aren't as pretty as Stew-Mac's, but they're perfectly functional, as I learned and you will learn below. Here is a shot of the spool clamps all laid out and ready for the top glueup.

I cut all of the dowel sections at once, and then cut little squares of cork and little squares of waxed paper. I drilled the dowel sections first, and then made stacks of cork and waxed paper so that when threaded onto the rod there would be a piece of waxed paper between every two pieces of cork (to keep the cork, and hence the jaws of the new clamps, from getting glued together) and drilled the stacks with the same drill press setup. I then threaded them all on one threaded rod. There was a nut and a washer at one end, and then I threaded a piece of dowel, a cork/waxed paper/cork stack, and a piece of dowel. This sequence was repeated until all pieces were on the rod, when I then put a washer at the top and threaded on another nut. I tightened the nut, and presto! the whole thing was clamped and glued.

Lesson learned - if you do this, wax the threaded rod before the glueup. The dowel sections stuck to the rod in some places and required some effort, including a heat gun in two or three cases, to get them off the rod. Oh, and the rod was toocaked with hardened glue to use for making the clamps themselves as well.

These pairs of dowel were then threaded onto 6" pieces of threaded rod with a hex nut at one end (the fixed end) and a wingnut at the other end (the moveable end) with big fender washers under both nuts.

These clamps are invaluable for gluing on the top and back. With the cork lining you don't even need cauls.

I then glued on the top. Here are some photos:

And here are the results:

I did the back today. Photos: