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Just curious, how do you guys that use spool clamps keep your body shape outside of the mold? Aside from the sides going wonky, it seems like a nice method for getting even pressure. I'm currently using a go bar deck but I don't really care for it for this.

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Hutch

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

I don't use spool clamps
gluing up outside the mold is difficult. It is about neck block control if that gets out of position it makes setting a neck more difficult . You can drill the mold to allow use of the spool clamps .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

With the back glued on and pretty thick, reversed kerf linings I don't find the sides wanting to move much. I also build with a fairly sharp cutaway which I guess is also stiffening that side at least.

Dave

Dentellones for the top, spool clamps for the back. Maybe laminated sides with solid linings would be stiff enough to handle, but regular sides are too floppy until you get one plate glued.

You could drill holes in the mold for the spool clamps to pass through but in my opinion that adds a lot of time to putting the clamps on.

I use solid laminated linings which are made/laminated inside the rim while it is firmly attached to the mold. Once they are glued in, there is not much movement in the rim. Add to that the back braces keying into the liners and the top braces (north of the X) doing the same, I don’t really worry about the shape changing outside of the mold.

That is not to say that there is zero movement, I’m sure there is some. I’m just saying that it does it seem to have any ill effects. I haven’t really ever tried to put a completed body back in the mold so who knows. I will say that my center lines line up on ends of the box and the bridge plates are where they need to be.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I can see the shape changing out of the mold, but I have less experience than you guys. I would not have even though of it until a recent incident.

25 years ago a friend abandoned a classical build just needing the top bindings and fingerboard. The binding and purfling channels were already cut. He gave the guitar to me. It had the sound hole in the lower small bought area. It had cracks in the top which I felt I was not qualified to repair, and other cracks and loose braces. So I recently decided to re-top it and get inside to repair open glue joints. Upon removing the top, the distance from the end and tail blocks increased almost 1/4", causing the neck to angle back-- not good for a classical. The sides also spread a little at the waist. I am still working on this, but I cobbled together a bracket to hold the sides together at the waist from underneath, and another to force the end/tail blocks together. I am hoping that if the old, defective top could resist the imposed stresses for 25 years, then once I get the new top on and remove the brackets, it will hold its shape.

I am salvaging this out of sentimentality. It is taking a lot more work than a scratch build, but I have never repaired anything before.

Just to reiterate that my post above was referring to my use of solid linings. I do not think a rim with regular kerf linings will be stable enough to hold its shape on its own. In your example, you removed the top from a rim that I assume only had dentilones. That meant that the only think holding the shape was the thin side. I’m not surprised that it changed shape. I am a bit confused about how it changed shape I. The manner you measured. I’m surprised the length could get longer while the waist got wider. Did the lower bout get narrower?

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Yes, it had kerfed linings on the top, laminated but slim on the back. I did not measure each and every location, so I cannot answer all details. If the distance between the blocks got longer thus pulling the radius at the waist flatter, then those two reactions could result in what I observed.

Also, because I was not building anything at the time, the humidifier was off, which might have made things worse (or not).

Reverse kerfed linings would do much the same as solid linings. They don't add much or any stiffness once the plates are glued, but before that, the sides are very rigid. I use two piece molds and glue the top and back on with spreaders on the inside that then come out through the soundhole. With archtops I glue the back on while in the mold with spreaders and then remove the spreaders before gluing the top on.

been building for 20 year
here is what I do. Taking the guitar out of the mold to glue a top or back on is counter productive
https://www.youtube.com/watch?v=M8qAvQ5ExSE

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

John, I like the mat and Masonite you're using. I don't have those nice bars you have. I make my own from wood. I had a bad accident with them the other day when one broke while I was inserting it. Got a a bad cut on the palm of my hand, blood on my clothes . I may have to invest in something better.

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Hutch

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

Yes I used wood hickory was the best but they can and do break
I have seen people make go bars using tubes and springs
there are many ways to do this. I never saw the point of removing sides from a mold to close the box. It is all about symmetry
and neck block control There are many ways to do tasks find the technique that works the best for you.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I think you're right about keeping it in the mold. I removed the sticks this morning and this body absolutely fits the mold tight after removing the internal spreaders. I'm very pleased with the outcome and I'm dropping the idea of using spool clamps. I just need some better sticks.

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Hutch

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

A lot of us use fiberglass rods. I've been using mine for over 10 years and never had one break. Mine are 3/16" and came from a kite supply store. They provide about 7 lbs of force each. Get the rubber tips too if you go this route.

Sent from my SM-G970U using Tapatalk

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Steve Smith
"Music is what feelings sound like"

$5 apiece is a little expensive for my taste considering I would like at least 30 of them. After cutting 15 them in half that comes to $75, I'll continue with wood. I just bought a EIR back and side set for that.

I've found walnut to make pretty good sticks and haven't broken one yet. It was the maple I just cut that broke numerous times. Probably just bad pieces with runout.

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Hutch

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

Bamboo works for me. It's free and can serve to make fishing poles too. The go-bar deck is on bearings underneath so I can spin it around like a lazy-susan and save space.

I don't know where to get free bamboo but I would like to try it.

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Hutch

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

I think everybody develops his own techniques, or goes nuts trying to. I've happily used spool clamps to clamp tops and backs in place, BUT the flexibility of the rim and the wandering angle of the neck block needed addressing. I used reversed kerfing to stiffen the rim and the neck attachment process offered by Luthier's Cool Tools. I also tied a transverse brace to the neck block with a filler under the fingerboard location before setting neck angle, trimming and tapering to suit. It gives me a rigid rim which doesn't distort when attaching the top and back. Used it on four projects.

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Peter Havriluk

I drilled holes in one of my forms, but it does take a long time to tighten all those wing nuts. So I finally made a bunch of cam clamps which reach over the form and can be set quickly.

Wow, that's the ideal setup. I built 3 cam clamps and I don't think I ever want do that again. It's very cost or time prohibitive for me but if time and money were no object I'd do it this way, I think.

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Hutch

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

50 clamps had a material cost of about $150 and it took me about a week to build. It was quite a project but I am glad I bit the bullet and got it done. I felt like I had given every other method a fair chance and they all had short comings. The thing that really forced me to go this route was building a replacement body for a 1931 Martin O-18 that had no bindings. I wanted zero gaps on the joints since they were exposed.

I know where you can get all the "free" bamboo you could need (unfortunately), for the price of the postage. My wife planted a few pieces at her parents house, which over the years has taken over the back yard. It is probably 30 feet tall, and a couple of inches in diameter.
If you are ever near Cecil County, Md. you are welcome to cut all you want.
I have been trying to find uses for it to make cutting it a positive experience rather than the sisyphean task it seems to be.

I won't be planting any of that.

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Hutch

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

Hutch,
I have found a kite supply where 3/16"x48" fiberglass spars are $2.70 each and end caps are $8 for 60 of them so @$50 for 30 go bars (Fly Market Kites). Like Steve, mine have lasted 10+ years with no breaks. Build a deck, you'll find lots of things to use it for.

Same negative experience at a home I owned 1999-2007. The prior owner had planted some along a fence. It's stubborn stuff.