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Started the process of migrating all the learnings from the last series of 00s to my D shaped model. This is the template I use to locate and drill the registration holes into the top and back plates which are used throughout the rest of the build.

This design is from our very own Dave Farmer. The slots have a simple catch that allows trapping the joined plates for drilling.

Having this as acrylic lets me see exactly where things like the bridge and fretboard will land on the plate, work around defects, align the grain, etc… it’s used for both the soundboard and back plates.







Brad


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Hey thanks Brian! I used double sided tape to adhere it to the side, it can come off but might cause slight damage to the shellac underneath. Thinking of trying out rare earth magnets like Kris Barnett for the next one.

Brad I was wondering if you had to make allowances for the curvature of the soundboard and the curvature and slope of the back in the spacing of the bush placements?

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

That is a great question!

The short answer is it’s TBD but I expect I will probably need to turn the holes in the tabs to ovals.

The slightly longer answer :

So far I’m using the tabs and locating holes only for pinning the plate when routing the outline, and then in a fixture on the CNC for registering to cut the rosette channel and sound hole. I haven’t used them for alignment to the mold when gluing the plates on….yet.

That being said, I do expect it to work and going from a 1/4” hole to a 1/4” wide oval should be easy enough to do accurately and it should only need widened slightly in the north / south directions to accommodate the curvatures.

What are your thoughts, Colin? I am modeling up the molds and will have some real world experience soon.


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A different take on armrests. I really like the armrest (wood match with side is GREAT) Brian (oval soundhole) posted earlier in the thread. Especially like the removable magnet attachment idea.

I took a different approach, adding the rest outside the lower bout and mounted to the binding channel.

Jury is still out on how players will like it. I like that it doesn't visually interrupt the classic lines of body shape. Dark wood kind of makes it disappear.

Brian Itzkin's works for me too, strangely, knowing it is an add on, my visual sense makes the body shape symmetry somehow complete.

Finishing bridge details on this one, Macassar. Here's the armrest:



Have a great Memorial weekend!
Brian R

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Brian R, Wood Mechanic
N8ZED

Sounds just about right, ovals should work fine.
I've been thinking to do something similar since watching Michael Bashkin's video from stewmac.
And I would imagine you'd only need that in the butt end of the mold.
Fortunately I don't have the added complication of CNC/computer stuff

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Updated bending forms for the D shaped model are happening today!







Brad


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These came out really nice. I’m considering just doweling them together and wicking in CA! Anyone doing that?







Brad


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I don't think I'd try CA on anything that big Brad. First it would have to be thin CA to wick in. You'd never know how well it was coated. And plywood veneers are pretty absorbent and the CA might just soak in and not provide the adhesion you want. I'd use Titebond if it were me.

Slightly off topic - when I made my bending forms I tested a bunch of finishes to seal them up a bit and to my surprise shellac held up to heat better than the others which turned gummy, which both water based and oil based did.

CNC is mighty handy for projects like this! Nice work.

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Brian R, Wood Mechanic
N8ZED

I did one with CA and one with Titebond. Let’s check back in a year.



Yes, outside of maybe Dave Farmer or Nigel Forster with their shaper skills, the CNC cannot be beat for this job!


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I'm doing a "copy" of a 1757 Guadagnini viola. He made the back smaller than the belly. I did that on my cello. It isn't as hard as it seems. What WAS hard, was putting a "binding" on the ribs. I cut the rib stock out of the back. Usually the back has more stock on it for doing that, but this gave me 35 mm wide ribs, and that wasn't enough. I had to glue the c bouts on. Glue the linings on the c bouts. Mark/cut the binding depth. Remove the top and bottom of the ribs with a chisel. Bend and glue on the Katalox binding. Rinse and repeat.

In contrast to Guitar work, (well maybe not MY guitar work) the outline of a violin/viola cello is really only real close at the ends, and the corners. The c bout is usually pretty good, but the others can be off some. Now put them on an angle, and they can be off more. These didn't come out too bad. You can see how much smaller the back is than the front with my hardboard form. I have one for the front, and one for the back.

The corners are all different, and the line between the corners is angled in all directions.

This is the first time that I've ever paid much attention to ribs. I usually think of them as something to hold the belly and back in place. They don't do much on violins, since they have the corners. But they probably contribute some to the sound.

This time they will actually make a statement. So they have to be nice. I'll finish scraping them, and put them somewhere where they won't get messed up.

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Why be normal?

Your stuff is never boring, Ken. I like that.

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"Act your age, not your shoe size" - Prince

First couple of coats of nitro. A long story as I built the sister one to this in 2013 and this body was sitting ever since due to a mistake that bothered me. I guess it wasn't too bad. Pau Ferro and curly redwood with flame maple binding. 000 12 fret. Using Benedetto's schedule as I always have although I do a 50/50 last coat after levelling that almost doesn't need buffing. Used clear frisket for the bridge footprint as I had it on hand and ran out of tape. First time. We'll see.

Darrel, I used clear frisket on a couple recently. I learned right away even thou its supposed to be low tack I pulled some spruce fibers that needed repair.

On redwood and cedar I'd be even more careful.

I liked it for my finishes as it's thin and I can wipe finishing pads right over it and barely notice it.

When you go to remove it I'd recommend pulling it off from the corners in to the center, fold it right back on itself as you pull so you have no direct lifting action, pull at a 45 degree angle to the grain and go slowly. Once I started that it was great. Really, that's good practice with tape anyway but I expected frisket to be sooo good I let down my guard, don't.

My mistake was in removing tape outside the bridge footprint and it had only been down for minutes.

Love that redwood and rosette!

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Brian R, Wood Mechanic
N8ZED

Thanks for the tips Brian. I’ll be careful.

I've recently started working with Guitar Salon International and have made some progress on my first guitar for them; it's been a dream to work with GSI since my teens and feels a bit surreal for that to be reality. I'm using very old bear claw German spruce for the soundboard and old growth Indian rosewood originally imported in 1953 for an archery bow manufacturer in Queens NYC

Well. The only photos you need on how to do a neat slot head. It would have been a shame to make a bow out of that wood.

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Why be normal?

Very nice! Looks like flawless detail and workmanship.

After rearranging the shop and making a permanent spot for my buffer, I noticed this piece of Braz. Totally warped but I figure it's got to be used. I cut into 1 1/2" strips, flattened and clamped it. We'll see, Either a fretboard or back strip like d35s.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Coffee break.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

A while back I posted about assembling a Romanillos "Moorish Arch" style rosette.
Here is the finished guitar.
I let it sit for quite a while before the final buffing session today.
The rosette was an...adventure.
I had enough arches left over for the inlay on the tie-block.
I used the Romanillos bracing plan per Roy Courtnall.
It has lots of volume and the tone seems balanced.
Very happy with this one!

Wow really nice Robbie!

Really lovely, nice work.


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Mighty nice Rob!! Yeah, all of it!

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Brian R, Wood Mechanic
N8ZED

Doing the side of the little baroque guitar/mandolin I used the pattern that I made up out of hardboard. It works pretty good. the smaller form needs to be bent fairly close, because it doesn't have a lot of room to push it where you want it. I decided to glue the linings on first. It did eat I want it to do, hold the form to the right shape when gluing it on the belly. It does have a little spring, but not much. I'l do the other side, glue the blocks on, and then the sides.

The plan calls for about 4 or 5 tentelones tacking the sides in place, and then a rope glued in the entire perimeter.

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Why be normal?