Paul,

Yes, I would definitely recommend starting with as early of an O as possible to gain the benefit of the thinner, hand-laid bowl. If you can find a 60s O that has the molded fiberglass kerfing, that would be even better. IMO, the molded kerfing used on the 60s Os acts like the suspension ring used on the Adamii. I'm not sure when O went to the thick plastic kerfing, but both of my 1970s CL use them. As you know, my 1619 doesn't seem to suffer too much from this 'handicap.' I was surprised how much my 1619 sounded like 485.

Torrefied Adirondack spruce soundboards are available. I bought mine through Blues Creek Guitars, but they're out of stock right now.

RC Tonewood has some torrefied Adirondack spruce, (See: Torrefied Adirondack Red Spruce) as does Colonial Tonewoods. (See: Torrefied Adirondack Spruce Guitar Tops) Both are pretty pricey, but not as expensive as what I paid through Blues Creek Guitars.

Torrefied Adirondack braces might be a little more difficult to come by. Stewmac is the only supplier I've seen that offers torrefied brace wood, but that's Sitka. A lot of places sell Adirondack spruce brace stock, but none that I've seen sell torrefied Adirondack.

If you recall from our last episode, Jay ordered two sets of torrefied Sitka spruce wood from Stewmac. When the order arrived, both sets were very nice looking, but they didn't match each other in grain or coloration. (batch 1)

So, we sent the least desirable set back to Stewmac and they sent out a replacement set once they came back into stock. (batch 2)

The batch 2 wood was still very nice, but alas, while a part of the grain was as tight as batch 1, it didn't have the silking or the coloration of batch 1.

After some consideration, Jay decided that we would make this a two-piece top using batch 1. As much as we wanted to duplicate the originality of the guitar, this was proving very difficult to do.

Here's batch 1. Notice the tight grain and beautiful silking.

Batch 1 behind the top template that gives a good idea how the guitar will look once it's complete.

Here's batch 2. Slightly looser grain and not as much silking.

Here's batch 2 behind the top template.

It's worth noting that both batches of wood have really nice tap tones and I'm going to keep batch 2 and use it on my 1978 1617. I'm going to buy some torrefied Sitka spruce uncut brace stock to duplicate the brace pattern on my 1976 1619 CL.

Here's a pic showing batch 1 and 2 behind the top template that shows the difference in coloration between the two. It's just different enough that the three-piece top would stand out for all the wrong reasons.

Just for the fun of it, I sprayed batch 1 with naptha to simulate what the wood will look like under the final finish, then compared it to the original top.

Now that this is settled, I'm going to get started on jointing the batch 1, then do some experimentation to taper the top just like was done on the original, which is no simple task.

Another area that needs development is the headstock markings. I found the font (Arabian Normal) online. I also found a company that supplies components that will allow me to create custom rub-down transfers using satin gold like what was used on the original guitar.

Here's a mock-up of the markings. Next-up is to make the rub-downs.

For some reason, Dan omitted my other request. When we failed to match three planks on the 2nd try with Stewmac, I asked him to go 

HERE

to see if he could find a blade we could use to recreate the three planks in the original top. It was just a couple hours drive for him.

For some reason we lost our connection and I guess his phone was on the blink for several days after that, because it appeared he couldnt hear it ring.

Anyway...this remains a project that continues to get better with each post...thanks again Dan!

The stuff I needed to continue has arrived and work is continuing.

As you may recall, the top wood needs to be tapered. There are two ways to do this, well, three actually.

1) Use a jack plane and taper it by hand.
2) Use a power sander (orbital or belt) and taper it by hand.
3) Make a tapered fixture to hold the wood at the precise angle needed and run it through a thickness sander.

I don't relish choice #1 so, this method is out.

I have a orbital sander and tried tapering some scrap spruce. This is a long, laborious process, so this method is out, too.

Which brings us to choice #3. I had talked to the woodworking guy about the fixture previously and he made suggestions about the spacing and thickness of the wood used and we agreed that 1/4" birch ply spaced on 2" squares with a 1/4" birch ply top would probably be sufficient to hold the weight of the pressure rollers without distorting the top wood. In the end I decided to add a bottom layer of 1/4" ply to make the fixture very stiff. With a top layer alone, it might want to bend. Adding a bottom layer forms a cantilever beam.

Luckily, my laser-cutting guy is able to cut 1/4" birch ply. So, I was able to design the parts needed. Basically, the top wood will need to taper from 1/8" (.125") at the top by the neck to 3/32" (.094") down near the bottom of the lower bout. One of the nice things about CAD-designed laser-cut parts is that the measurements can be very precise.

At 2" centers, the size of the fixture requires 13 ribs and 11 spars. And, here they are.

Another requirement is that the fixture be very flat. If there's any cupping or curvature, it will transfer this warping to the top wood when it goes through the sander. So, my solution is to use the stone table tops from a couple of end tables that belonged to my wife's granddad. Not only are they very flat, but because they're heavy, they will clam the fixture with a very even pressure while the glue dries.

First, lay down the base and cover it with a piece of visqueen.

Lay down the bottom layer of wood. The maximum size of wood the laser cutter can handle is 12" x 48", so I had to make the top and bottom layers in two pieces. The brown lines are alignment marks I added and were etched by the laser.

Add beads of glue (Hysol 9462) where the ribs and spars will be.

Add the spars, and put a bead of glue on top.

Add the ribs and put a bead of glue on top of these, too.

Add the first half of the top layer.

Add the second layer and tape some visqueen on top of that to keep the glue from sticking to the stone.

Lastly, put the stone on top and let the glue dry.

I'll pull the fixture out later today.

In the meantime, I'm going to prepare the practice wood for jointing. One of the things the woodworking guy and I agreed on was that we should practice first before we run the real top wood through the sander. I also bought more practice wood to use to knock the rust from my rosette routing and sound hole cutting skills.

I've got the practice top wood jointed and I'm waiting for the glue to dry.

I've been wanting to try Old Brown Glue for a while now, so I decided the practice top wood joint would be a good place to try it. It's hide glue that's had urea added to it to extend the working time. You heat it up in a double-boiler just like regular hide glue to thin it down. So far, I like it.

I'll know tomorrow when I pull the top wood out of the go bar deck how strong the glue is.

After that, I'll take a couple of practice runs with the router and circle cutting tool and if everything works okay, I'll route the rosette groove and cut the sound hole on the practice wood and then again, on the torrefied top wood.

heeheehee     ... but not a blade in sight!

+1    Keep on keepin' on Dan!

Thanks, guys. I'm glad you enjoy me geeking out.

Thanks for the kind words, Paul. Yeah, once you realize that guitars are just bits and pieces of wood that have been glued and screwed together working on them becomes a lot less intimidating. I've been working on my own guitars since before I knew better. The knowledge gained building and repairing model airplanes transfers directly to building and repairing guitars, especially since the tools and materials are the same for both.

And, speaking of geeking out, back to the thread. I pulled the sanding fixture out from between the stones and added alignment strips. The woodworking guy suggested I add these so prevent the wood from slipping out of the fixture as it runs through the sander.

I also pulled the practice wood out of the go bar deck. Here it is sitting in the fixture. The Old Brown Glue seems to have worked pretty well.

And, here's the final wood sitting in the fixture.

The next job is to route the rosette groove and cut the sound hole. Once these are done on both the practice wood and the final wood, I'll take them in to get the taper sanded.

Measuring the top wood that came off Jay's guitar revealed that it is 1/8" at the top and 3/32" at the bottom. Paul confirmed this with his 1968 Balladeer.

I had a few free hours today, so I decided it was time to route the grooves and cut the sound holes into the practice top and the final torrefied top.

Before beginning, I cut the notches in the upper bout and fit the wood to the neck. I also decided to leave cutting the outline until after the wood is tapered.

I wasn't as rusty as I thought. I only needed four attempts on the extra practice wood I ordered. The final one turned out nearly perfect. I figured it was now or never, so I did the practice top first.

Here's the practice top, ready for the sander.

And, the torrefied top.

Here's the rosette in the torrefied top.

And, how it'll look on the guitar.

I'll call the woodworking shop first thing Monday morning and make an appointment to sand the tops.

Pics to follow. Just for the fun of it, I'll take some pics during the sanding process to share with everyone.