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Today I worked on my least favorite part of the guitar which is resawing the back. The billet has been air drying for about two weeks in the cool spring air and has lost maybe half its original weight. The log that it was split out of was about 18” diameter which makes getting a full 8” wedge rather difficult. If I had a couple of more inches to work with I would have continued with riving the pieces continuing with the scrub plane, like the sides that were roughed out earlier this week. However because the tolerances are so tight I needed to make sure I could get two usable piece so I broke out the large timber saw and went to work. It took about 45 minute to resaw the billet into to matching panels, to be honest it wasn’t that bad.

After resawing, it was time to plane the pieces into uniform thicknesses about 3/8” thick. This step took about another 45 minutes. Now I consider myself in pretty good shape but I’m beat. I love working with hand tools but there are some things that are just hard work, plain and simple.

I will be wrapping these thin boards in brown kraft paper for a few days to let them slowly release a bit more free water. I have not decided how I will complete the drying process. Under normal circumstances I would let the boards’ air dry. The problem with this route is that I intend to use it on my current build. I have been reading about drying thin lumber and found some useful information from wood turners. One way they dry their thin walled bowl turnings is to submerge the work in a bath of denatured alcohol, which replaces the water in the wood with the alcohol that will evaporate much faster than water. Many turners claim to have had very good results with this technique. My other option is to cook the wood in my make shift light bulb oven (think “easy-bake oven”). I have used this method when making post and rung chairs. The chair rungs are cooked for a few days which left them bone dry. I would estimate that the 3/8”x8”x24” boards’ would be dry in 3-4 days, but I’ve never attempted this for my guitars. I think I’ll cook a test piece in the oven before committing to one way or another.

Yo Chris,

You bout the only dude me know that still uses hand rip saws. Good go for you.

ummm regarding that cook box of yours...

how many light bulbs in there?
whats the wattage
do you leave a tray of water in there?
and is that box sealed up air tight?

in other words....what I gotta know that I don't know to make me one of them cookers?

thank you

peace and carrots

Padma

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Audiences and dispensations on Thursdays ~ by appointment only.


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how many light bulbs in there? I use 3
whats the wattage 75-100, gets the temp up to about 150 degrees
do you leave a tray of water in there?Not for the chair rungs, will have to see for the backs?
and is that box sealed up air tight? No, Mine is just a few boards nails together.

Chris,

Is that a slab of granite resting on top of stickers to keep the back from curling?
Rick

Is that a slab of granite resting on top of stickers to keep the back from curling?
Yes, The quartered wood is pretty stable but I thought is couldn't hurt to add some weight.

Here's an update on my latest build. "I started drinking my finishing supplies". Just kidding but a few weeks ago I really felt like it, you see while working on the rosette I went a bit to deep and cut all the way through the top. I hung the top on the wall and haven’t touched it until today. Decided to go with a larger sound hole reinforcement, not my first choice but better than scrapping the top.

During this time the walnut sides and back pieces were dried down to 0% moisture and have been acclimating in the shop 45% R.H. for a week or so. They seem to be stable, hopefully will stay that way.

Sorry for the lapse in postings, sometimes I have to just move on to other things for awhile.

This weekend I joined the back plates and glued them up using a rub joint, no clamps. I am still amazed at how well this works, no more fancy clamps for me! After letting the back dry for 24 hours I thicknessed it with a jack plane. During the time waiting for the plates to dry I made linings and brace stock.

I'm super pleased with the color of this walnut and think it will make a really beautiful guitar. The great thing is I have a lot more sets waiting out back!

You may have noticed that this is not the same set that I posted before. When working the blanks down I realized that I never accounted for the extra 1 1/2" for the heal of the neck and the other back was not quite long enough. Good thing I was drying more than one set during the past few weeks. I decided to save the other back for a smaller instrument and just grabbed another set to work with.

Disaster… The horror… Yes it happens to the best of us, and if you have followed this thread you know it happens to me quite often. Well the cedar top I had been working with ended up a bit thin after joining the four individual pieces (I joined two pieces then planed smooth, then glued the two halves together and planed again). Having the top so thin I was really struggling with the rosette. The rosette was taking up a huge amount of time and my fun hobby was turning into a disappointing drudgery. I decided that I needed to switch gears to get this build rolling again, so I ordered a Sitka top and rosette from LMII.

I joined the top with hide glue and a rub joint and plowed out the rosette channel with my rosette cutter and small router plane. I will be gluing the rosette tonight using fish glue.

While waiting for the top to arrive I worked on the back bracing. Pretty straight forward, I was shooting for a 20’ radius on the back but to be honest I just eyeballed it with a #4 plane while holding the braces flat on a shooting board. The bracing was glued to the back with hide glue and a few caul clamps. I have a go-bar deck and radius dishes but wanted to take a more traditional approach on this build (just in case you haven’t figured that out yet).

I also started on cutting the linings. Call me crazy but I quite enjoy cutting the hundreds of kerfs in the quarter inch cherry. My set up is about as simple as it gets, a granite tile with a piece of hardwood super glued to it and a small brad to set the distance of the kerfs. The saw is a cheap Stanley dovetail saw I bought about twenty years ago when I first began woodworking. The saw has a 1” strips of aluminum can material taped to each end with metal duct work tape (I’ve used electrical tape and it works just as well). Once your ready you just go to your happy place and cut, cut, cut.

Disater

Can do forge ahead attitude

Knowing that they are called linings and not kerfings

I'm enjoying your thread Chris.
Carry on

Steve

This weekend I was able to spend a little bit of time on the top. The rosette turned out well and I planed the top down to around 2mm. Then I turned my attention to the fan bracing, here again I radiused the braces by eye and glued them on with hide glue. On my previous guitars I have really kept the inside of the box super clean of glue squeeze out, but today I decided to leave the glue on. Don’t get me wrong I’m not condoning sloppy work; it’s just that I’ve looked at photos of some historic guitars and they have glue all over inside. So what the heck I’m leaving it on this one. So the fan braces were glued on and then planed to about .13 as shown in the photo and then shaped with a chisel.

Chris-
I've decided to take the same attitude about pencil marks on the inside of the top. Might give somebody in the future a laugh or two.
I'm still going to be a bit careful with the inside back, as the 'Men Who Stare into Soundholes' must be appeased!


Cheers
John

Really fun thread!!

Chris I have a few questions if I may. Could you describe a bit more in detail this rub joint method you use? Also, could you give a bit more detail on your method of cutting the rosette? Specifically, which tools you are using and maybe the way you go about using the router plane?

These are all new to me and sound like something I would want to try.

Very much appreciate it.

Matt, here is an excerpt from an article Bob Flexner, author of “Understanding Wood Finishing”, did for popular woodworking. He does a better job at explaining a rub joint than I would give. I find it very easy to do and like the simplicity of it all.

Unlike other adhesives, hot animal hide glue bonds in two steps. An initial tacking occurs when the glue cools from its application temperature of 140-150° Fahrenheit to about 95°F. The bond becomes complete when the water evaporates out of the glue.
The initial tack allows you to glue two pieces of wood together without clamps. Simply apply the glue to both surfaces and rub the pieces together to work out the excess glue. As the glue cools, it gels and the pieces begin to stick. Position them correctly and let the glue dry to complete the bond.
As long as the pieces are not forced apart while the glue is still in the gel state, the tack is strong enough to create a good bond. On the other hand, if you don’t like the positioning of the pieces, you can separate them for some time before the bond becomes too strong.
The glue blocks you see behind legs and on the inside corners of old case furniture were positioned with this rubbing technique, called a “rub joint.” It’s not uncommon to see glue blocks still sound after 200 years, especially if the grain of both parts runs parallel.
You can use a rub joint to replace broken pieces on carvings, small pieces of veneer, and other parts that would be difficult to clamp. You can also strengthen case furniture by regluing old glue blocks or by inserting new ones. Just be sure to remove chunks of old glue to create room for rubbing, and remember that the surfaces have to fit snugly for a good bond. You can’t glue air spaces.
Yellow glue offers some degree of tack, so you can sometimes perform these tasks with this glue. But the tack is much weaker, so the slightest pressure during drying will move the parts and destroy the bond.
The technique of “hammer veneering,” which is used to apply veneer using hot hide glue, is a form of rub joint.
On the question of using a router plane to plow out a channel for the rosette. The biggest pieces of advice I can give you is take your time, don’t get carried away and try to remove to much material at once and learn to read the grain of the wood your working.

Glad to hear you’re enjoying the thread.

Here is the soundboard warts and all, or should I say glue and all. It’s a pretty straight forward fan pattern. I wasn’t too concerned about the exact placement of all the pieces but tried to keep everything symmetrical by eye. Sense I decided to leave the glue squeeze out, the top has a bit of character to it. I don’t know how I feel about leaving the glue on yet?

I’m including some photos of the bone, nut and saddle blanks that I’ve started preparing. The bone came from the local butcher. I’ve found that if you tell people that you build guitars they are so fascinated with it all, that they offer all sort of help. I explained to the butcher I needed a fairly thick and dense piece of bone. He told me to stop back later that day and he had a nice chunk of bone for me to use. He didn’t charge me for the bone but I did pick up some brats for the grill. The bone cuts fairly easy with a medium toothed saw. I found that a hack saw blade would clog up while cutting so I switched to a coarser blade and it worked just fine. After the blanks were cut out I used a coarse rasp to square them up. The blanks are now soaking in a small jar of white gas to extract the oils from the bone.

Bending the sides is the reason I became interested in building guitars. Taking a piece of wood and heating it over a hot pipe, feeling it become pliable under your hands is one of the joys in life. My set up is just a steel pipe with a charcoal starter inside, no different than all the other ones out there except I filled the void on the inside of the pipe with copper nails. It takes a bit longer to heat up but once I get it hot it stays hot for a long time. I like bending everything from 350-400 F, anything lower and it takes too long and hotter, well you know what happens. The photo shows my little thermometer that I wire to the pipe as it heats up, when I decide to start; it is just cut off with a wire cutters. Kind of different but I’ve been doing it for so long I just keep doing it.

The bending went fine; I used the back of the guitar as my template and really took my time getting the bends spot on since I will not be using a mold. After the sides were bent I clamped them in the neck and will let them sit for a day or so.

Our family got a new puppy last week, so needless to say it is taking up a large portion of my free time. I did get into the shop for a few hours this weekend and was able to attach the neck to the sides with wedges (no glue) and also attach the top with glue-blocks.

Beautiful impressive work Chris, and a cute puppy.

Bob