Step 2 (1/2)

So, my next task involved disassembly of the bar supports. First, I laid out the replacement pieces as you can see in the following picture. This is the naturals frame, upside down, with new wood clamped to old.

My next step was to take apart some of the old support frame. I removed the cross pieces, then detached the old rabbeted end piece from the decorative material above. I rabbeted the ends of the new cross pieces (by hand, thanks again mom for the X-Acto set last Christmas) and the new end piece, as seen in the following pictures. The first shows the end piece, and the second shows how it will fit on the end of the support frame on top of the base.

This last picture shows the two cross pieces in place, not cut to length.

At this point there has been a bit of a delay. I have been trying to find a good source of maple for the string support pins, which has been a challenge. I finally found a local planing mill that can cut some oak and maple to spec. They didn't get back to me with an estimate today (which irked me greatly; I'll have to call them again tomorrow), but they should be cutting me 180 1/4 X 1/2 inch pins (135 at 1 7/8 long, 45 at 3 3/8), plus pieces of oak for the base frame. I decided today that I will be abandoning the current split design, and using one larger central horizontal support for the base, instead of two that hook together. I will make the center legs out of 2 inch by 2 inch [fill in name of wood here] and the top frame will fit over it. This will make it only slightly harder to transport, but it should still fit through a door without too much trouble, especially with the floating bar supports. That means that to disassemble it I will have the natural and accidental bar support pieces, the main box, and the legs as separate parts. I drew a clumsy design in Paint to illustrate the new central leg support design, which will facilitate easy breakdown. I still need to decide whether to add sway stabilizers in place of the triangular pieces you see above around the legs. I am hoping this new design will help avoid the warping that happened in the current frame and is preventing it from fitting together flush.

My next step is to replace the left end of the naturals bar frame as I did the right. When I took them apart there were all sorts of nails and glue, nailed from both sides to make it really hard to disassemble. I am thinking I will use 1/4 or 3/8 inch hardwood pegs going through the structures instead of nails or screws. Please see the following clumsy visual reference. I'm not sure if this will lead to too much play in the joint; I'm still thinking about it.

After I get the bar support frame ready (as well as replace the front horizontal support of the accidentals frame) I will lay out all the bars to determine where the pins will go, mark the center lines for the pins, and mortise about 5/16 down into the horizontal support pieces. I will need to shave 1/32 from each side of the pins to match the old pins' thickness, but I like the idea of having a 1/4 inch mortised base to use for strength and stability. The old ones were just hand carved into about 3/16 inch cylinders and pounded into drilled holes, which has led many of them to snap off. Anyway, here's a picture of what the new pins will look like.

This will be more of a challenge than it seems, because I will be drilling, shaving, and mortising all 156 pins by hand. I have high hopes that the 1/4 inch mortise chisel I plan to get will be sharp and effective. If not, I will have to find a friend with a mortiser. The (lofty) goal is to set them all perfectly in place with no glue or fasteners and have them jiggle not a bit.

I plan to post another update once I have the bar frames completed. I hope to have the pins and base pieces back from the mill before Christmas.

Step 1

The first thing I decided to do was replace the horizontal bar supports. The three that need replacing are all approximately the same dimensions, but there is a 1/8" variation from one end to the other in two of them. I decided to just cut them all the same.

I had to decide which wood to use, and elected to just use red oak from the local big box home improvement store (Sorry, Home Depot, only parenthetical free advertising on this man's blog). This isn't a part of the instrument that will be visible and, well, I just wanted to get started as soon as possible. It took a long time to find a six-foot section of 1X4 without too much warping (they store 12-foot sections upright and don't rotate them, which just seems stupid to me, but I guess it saves a bunch of floor space). My neighbor has a portable table saw and let me come over and use it on his porch. One fun side benefit of trimming 1/8" off the 3/4" side (the 1 in the nominal 1X4) was ending up with a couple 1/16" by 6 foot slats, which I think will make very nice shingles or siding for a dollhouse project. Here's a photo of the three pieces, which I know will be super thrilling.

 This photo shows a closer look at the support posts, many of which have snapped off the bases. This view is from the accidental bar set, hence the gaps.

 Another view...

 ...and another. I am not the world's best photographer. Anyway, you can see in the above photo that I numbered all the posts (of which, surprisingly, only one was missing) so I can match them up later with the horizontal supports and see how high to mount the suspension cord.

 Here is a view of the far end posts of the accidental bar set. I elected not to remove any of these from the support, since they were still pretty solidly attached.

Many of the posts had to be encouraged to leave the horizontal support, but as the support was broken it had to be done. On the natural bar set there was one broken and one intact support, and the intact one was pretty badly warped so I need to replace both.

 Here is the accidental support. All the bars are turned over because I numbered them in pencil. You can see the heap of posts there also; I will need to make quite a few myself to replace broken or missing ones.

I laid out the keys on a blanket and then rolled them for storage. They will all need quite a bit of cleaning before they can be restrung and mounted.

Yep, tied them up with a nice square knot. The cord, incidentally, feels waxed or oiled and is in pretty good shape, but I had to cut it to get it off so it's unusable at this point.

Here is the natural bar set ready to work on. I finished the second set at about 1:30 this morning. Next up is making all the new posts, which I will initially do in hardwood. I think I will likely end up using modern metal ones in the end, since I would then be able to take the bars off without completely unstringing them. I'm not totally sure about it though, since the wood ones are sort of charming and most are still in good shape. Incidentally, the builder didn't glue any of the posts into the frame, they are just pounded in and held by friction. I could see plenty of places where he had to drill second holes because the initial hole didn't quite work, so I hope I have better luck planning my post locations.

More to come, probably not as soon as this one did.

One of those "What did I just get myself into" sorts of things

So, I just bought a marimba. I was looking for marimba mallets on KSL for kids and found a marimba listed instead that seemed to be in my price range. It is about 5 1/2 octaves (my current instrument is a 4-octave) and was (according to the seller) hand made in El Salvador 50 or so years ago out of Honduran mahogany. It has a lot of character, which is probably a good thing (the jury is still out on the carved pastoral scene on the front). The bars have a good sound and are mostly in tune.

Sounds great, right? Yep. The downside of the situation is that over the years it has gotten really beat up. Parts of the base are broken, string support posts are snapped or missing, and part of the frame is warped. Some previous owner committed several crimes against wood including wiring part of it together, using nails the size of which was incredibly wrong, tacking part of it together badly using brads, and gluing with no apparent knowledge of the existence of clamping technology. Here are some "before" pictures. I will post updates as I work on it.

This shows the whole pastoral scene on the front panel. The painted pieces were carved separately and attached. I'm hoping the wood under these pictures has been finished similar to the rest; I may remove them. What do you think, numerous potential commenters? Should I leave them or remove them?

This shows a close-up of the scene.

 You can see from this photo how the box and support pieces split in half. I am considering making the legs detachable for easier portability.

A close-up of the amazingly professional repair job using copper wire.

Splits like this are pretty common in the base/foundation.

You can see the terrible nailing job done here. You can't tell very well, but it was also glued.

The naturals or "white" keys. The rear horizontal piece has snapped. The bars are made of padouk, which is rosewood's slightly poorer cousin.

The accidentals or "black" keys. You can see hanging off the from string numerous string support posts, also of hardwood, many of which have snapped off and many others of which are merely out of the holes. The partial piece at the front of the keys is part of the horizontal support piece, part of which is missing.

A close-up of the lowest naturals. You can see the beautiful wood finish here, and see more of the hardwood posts. If you listen closely to your screen you will hear the thrilling low G resonating. This note sealed the deal for me. I'm not yet sure what it will sound like once it is repaired, but a higher A is matched pretty closely to A440 which means that it can be accompanied by a normally tuned piano, which was important for me. Some of the octave intervals are tuned a little off and the overtones/second resonance are not superbly tuned, but it was handmade so some variation is to be expected. Like I said, the instrument has character.

This is the only obviously damaged key, and the repair that makes me the most angry. The bar broke in half along the grain and was clumsily glued back together, without any apparent clamping or with an expanding glue. The note still sounds ok, but I will need to see if I can find a safe glue solvent that will dissolve it without harming the wood so I can do a better job. This is the lowest accidental, a G flat. Interestingly (at least to those familiar with modern manufactured instruments), the range goes from the piano equivalent of two G flats below middle C (the G below the low C on my current marimba) to the fourth B above middle C (almost a full octave above my current 4-octave). I think this would probably qualify as an almost-5.5-octave xylorimba, but I'm not sure. Also in this photo you see the knotted support string; I will be replacing this series of knots with a modern-style hooked tension spring arrangement.

 The resonators are of wood, which (as my limited research reveals) is pretty common for Latin American instruments. Apparently this is also hardwood. The resonators each have a little hole in the bottom, which would be covered with pig gut membrane to produce a characteristic buzzing effect. I will not be recovering the holes. There are not nearly enough resonators for all the bars, and I'm not yet sure how many would be typical for an instrument of this type. This is the biggest question I have about the project...it would be very time-consuming and difficult to handmake resonators of this type for all the keys, and I'm not sure whether substituting a different kind of resonator will be acceptable or not (PVC, for example, is a cheap but ugly substitute, and aluminum commercial resonators would look wrong).

This is a sort of put together view of the marimba. The wood pieces on the accidentals are resonator supports. Obviously the front and back halves will be joined without the huge gap you see in the picture.

There is a fundamental question I need to face with this project, which will make a lot of my choices more difficult. That is, do I try to stay as faithful to the original construction as possible in terms of materials and methods, which would preserve the charm of the folk instrument, or do I substitute materials and methods that will make the design more robust? Honduran mahogany is not likely to be cheap or easy to find, so visible pieces like the legs would look noticeably different if I use a different wood. I have no idea what finish was used (it has a waxy feel, but could be anything) so it may be hard to duplicate. I don't like the idea of stripping the whole thing and refinishing it. The wood string support posts will be time-intensive to carve (although not that difficult) and replacing them with modern metal supports with rubber insulators would make for a more robust construction, but it would change the look. Input from readers, again, is welcome, especially as regards the aesthetics of the project and more especially still from readers with any experience in this area.

This will be a labor of love for me. My first priority is to make it playable by replacing the bar supports and string support posts (with wood initially), then I will work on the foundation frame. At least for a while, I will have two marimbas so any of you who are percussionists will be able to come play duets. :)

If anybody has friends who you think have special knowledge in this area that may be of assistance, feel free to share the link to the project. I will try to post regular updates.