So, I bought this bare bowl off another OFC member sometime last year and stashed it away into the someday pile.

It looks like that day has arrived. I guess I'll be doing four guitars at once, not just three.

I recently acquired a 1537 neck that is in pretty good condition. It's been played a lot, but otherwise it hasn't been abused.

I've been goofing around with moody p.i.'s 1537. I borrowed his 87C for a couple of weeks so I could satisfy my curiosity of how they sound since both of these guitars are rated among Ovation's best by quite a few people. For the most part, I like how both of these guitars sound, but truth be told, my ear has become accustomed to the sound of torrefied wood tops.

I originally planned to use the 1537 neck on an Elite version of the wood bowl Ovation I'm planning to build. But, I didn't want to wait that long to hear how a torrefied Quintad brace pattern sounded.

So, to coin a model airplane phrase, I decided to bash together a torrefied Quintad-braced Elite using the 1778T bowl and the 1537 neck. It's not going to be a permanent joining, just together long enough to hear how it sounds.

The heel is a little long for this bowl, but for this purpose, it will work fine.

If all goes well, these two necks will form the basis of two torrefied-top, wood-bowl Ovation guitars -- a Custom Legend and a 1537 Elite.

I took a photo of the Adamas braces from the Ovation Tribute site and imported it into CAD. I opened up the back of the 1537 and took some measurements of the braces, then drew them up.

I printed them at full-size, then spray-glued the templates to some 1/8" balsa sheet and cut them out.

I compared them to the braces in the 1537 and fine-tuned the profiles. Even though the test templates above are angled, the final templates will be rounded. It was easier to cut these out with an Xacto and a ruler than to hand-cut with all the curves.

Next job is to kit out the braces on all four guitars: 1528, 1612, 1117 and now, the 1778T(orrified).

Because this will be a torrefied wood top, I'm going to try to use a cross-grain piece of torrefied Sitka spruce sanded to either 1/32" or 3/64" thick  in place of the non-torrefied birch ply. Well, that is, if the guy I use can sand wood that thin.

The birch ply would definitely be stronger, but it also won't resonate like the torrefied spruce.

I was able to joint the top in preparation for joining and rough cut the braces.

I'm planning to join the tops for all four guitars at the same time so that I can take them down to the sanders and have them all thickness sanded together.

While each top is drying I'll be cutting out the braces. Top for the 1778T is being joined.

Referring back to the photo of the upper bout on the inside of the 1537, there is a cross-grain reinforcement. It looks to me like 1/32" birch plywood.

I'm not real keen on using birch plywood for this job, first because it's plywood and secondly because it's not torrefied. One of the main reasons why I use torrefied braces on the inside of the torrefied tops is so the braces have the same rate of expansion/contraction with changes in humidity. Using non-torrefied wood would change this. Unlike non-torrefied wood, torrefied wood doesn't really absorb moisture from the air. The second and most important reason is because the braces will of the same 'age' as the top, so they'll both have the same response. IOW, both are already 'broken in'.

So, my solution, or at least my first attempt at a solution, was to cut out 1" wide, 1/32" thick slices of the uncut torrefied brace stock.

The uncut brace stock is normally quartersawn. I was originally going to use another top, which is quartersawn, sanded down to 1/32" thick for this reinforcement. It occurred to me that quartersawn wood sanded that thin would be prone to cracking and splitting along the grain and would provide almost no reinforcement.

By cutting with the grain instead of across it would yield thin wood that is, essentially, flatsawn. IOW, thin, flexible, strong and not prone to splitting. Here's a drawing that shows the differences between quartersawn and flatsawn.

These will get glued edge-to-edge to form a thin sheet, which will get laminated to the underside of the upper bout. Then, I'll drill the sound holes.

I'm going to cut all of these to length, then laminate the scrap to a scrap piece of top wood. Once the glue has dried, I'll try drilling holes and see how it works. if the 1/32" reinforcements are too weak, then I'll cut new ones that are a little thicker, then try the drilling test again.

The outline of the top has been rough cut and the bridge alignment pin holes drilled.

The cross-grain strips are being laminated to the underside of the top. These will need to dry for a day. Once the glue is dry, I'll sand them smooth, then drill the epaulet holes.

This guitar will not be getting the epaulet leaves. Since this is a test piece, it'll be simplified for expediency.

Once the holes are drilled, I'll glue the braces into place.

Hi Jon,

Thanks for the kind words and you're welcome.

You could be right. I've never seen anything like it. Of the limited number of Elites I've seen, they either have the full width cross-grain plywood (1537) or individual pieces overlaid on the back of the holes outside the braces. (1768-7LTD, 2078TX-5)

Dan

Before attempting to drill holes in the top, I decided to mock up a couple of test pieces from the sound holes cut from the other tops.

I knew I needed several different sizes of drill bits to make the holes, the largest being 1-5/8", next largest 1-1/8", followed by a 1/2" and finally 3/8". I checked with Harbor Freight and they had a Forstner bit set which contained all these sizes for $38.

Here's the sample piece with most of the holes. The spacing between the 1-5/8" and 1-1/8" hole in this piece is only about 1/16", but the cross-grain doubler is doing a good job of keeping the sound board from splitting even when the holes are this closely spaced from each other.

The spacing on these two holes got closer because I made several attempts at the 1-5/8" hold and the drill bit wandered a little. When I do the sound board for real, I'll make sure to drill the hole(s) in one shot.

Next job is to mark the locations of the sound holes on the top and drill them out

I got the sound holes drilled. They aren't as perfect as what the MS could do, but for my purposes they'll work just fine.

Next job is to lay out and glue down the braces.