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Does anyone have a sure-fire way to lock the top and back down securely while you mark where the braces will be?

Brads? Rubber bands? Friends?

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Pat

I just use my hand to hold it. I can see where an excessive arch would be tricky. Rubber band sounds like a good idea to me. FWIW what I do is leave the brace ends long so they stick out real good. Then start with the upper bout by pressing down the back there and aligning everything, then it doesn't matter if it's rising above the lower bout. Once that is done I move down the ladder till I get to the last brace.

I use old bicycle tire tubes as clamps to glue the back on and that would certainly do the trick of holding the back on for you.

Cam clamps over the blocks. Just tight enough to hold the plate.

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http://www.Harvestmoonguitars.com

Same here. Plus I usually index the top to the neck block with a toothpick in the area under the fret board.

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Steve Smith
"Music is what feelings sound like"

A few spool clamps only as tight as needed to hold it all together.

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Bryan Bear PMoMC

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

With rim in mold and flat on a carpet scrap on the bench, we position the plate, then use a #4 and a #62 hand plane (or 2-3 three pound bags of lead bird shot) per end to keep things in place while the pocket locations are marked. The carpet scrap (we use carpet samples from a local carpet dealer) allows the rim to be easily rotated to mark both bass and treble sides.

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A constellation only takes shape when one maps the whole.
- Beth Brower

I just have two lead bags that I put on each end while it's flat on the bench...

Clamps for me- carefully! Just enough pressure to seat the brace ends against the rims. 15’ radius.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I have a question based on the replies so far. Is everyone placing the top or back on top of the sides and then marking the brace locations on the outside of the sides? I ask because I place the braced top or back on the radius dish braces up and then position the sides (in the body mold) on top and then mark exactly where the braces intersect the inside surface of the lining. To my mind, that eliminates a couple potential sources of error in locating the pockets accurately and no clamps other than gravity are needed because the weight of the body mold holds everything in place fine.

Of course, this wouldn't work with the adjustable mold that Terence shows in the photo above.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Jay, that seems like a reasonable way to do it. I typically hold the top or back with a couple of the large rubber bands from Stew Mac and mark on the outside. Its been working for me...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

I use solid (laminated) linings so by the time I am marking the brace locations on the rim, I am no longer in the mold. That makes it easier (for me) to mark everything. As demonstrated by the responses here, there are many, many ways to handle this part of the process. You get to pick what works for you and your methods. Threads like this are cool because you never know when you will pick up some little trick that you like better than what you have been doing.

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Bryan Bear PMoMC

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

I use the Robbie Obrien recommended trick of putting small bits of masking tape on the outside just below where each brace will hit. Then I clamp the top or back in place the same as John P. I then mark the braces just inside of the actual brace location on each side and cut with a router. Then use a safe edge file to slowly open up the channel to fit the actual brace width.

I've had good results (little or no gaps) from the very first build so it must be idiot proof.

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I'm curious, do you glue the top / back on without the rims in the mold? I used solid linings on a uke recently and thought I could skip the mold while putting on the top (the back was already on) but it did slip a little in the end. Not terribly, but I think I'll keep it in the mold from now on.

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I do. I use spool clamps for this. Occasionally, I consider putting holes in my molds to allow me to use the spool clamps in the mold but it just seems like too much work to be worth it. There may be some tiny changes in the shape of the rim once I take it out of the mold but I've never noticed and what little there might be would certainly be nothing that concerns me. If I were doing something like falcate bracing where I needed to bring braces between the pin holes, I would be more concerned. . . I use X bracing and lay everything out from the center-line and the neck side of the rim. If the lower bout was a little wider or narrower (or if the tail was a little longer or shorter the bridge still ends up where it was supposed to be. . . This heresy may make some here cringe though so have a grain or two of salt handy when you read this.

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Bryan Bear PMoMC

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

I place the assembled sides in the mould on the top/back plates on the appropriate radius dish to mark brace pockets (and the marriage strip which is glued a little over length), same as some others.
A little off topic, but just a comment on
"just inside of the actual brace location on each side and cut with a router"
I would just add to this that I mark the depth I need, and cut the linings with a fine saw from the inside of the ribs at an angle down to the depth mark first before using the router set to depth - stops chipping out the linings.

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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.

I've been chiseling out the pockets like a sucker and not going through the whole rim. It is still fast enough that I donn't think it would be worth it for me to pull out the router and set it up. But, all this talk about routers makes me realize I should just cut my notches all the way through the rim. That will make it even faster to fit everything!

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Bryan Bear PMoMC

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

After marking locations I put a straightedge across the rims and mark the boundaries of the pockets, cut on those lines with an Xacto razor saw, and rout out the pocket with a 1/8” bit on the StweMac base. I always leave the side intact. Clean up,with a small chisel if needed. Goes pretty fast, but the final fitting of the braces to the pockets is always tedious for me.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I do as Jay, mark both sides of brace with fine pencil marking both top and back before either
is glued to rims. One of the few times I use a dremil is to route the pockets. Set depth, sneek up to
the mark holding short of the sides, a bit more noisie than with a chisel but swift. Easy peasy.
Like what Terrence does, except with a 1/16th bit.
Ken

I’m curious about leaving the side material. It goes away when routing the binding ledge anyway, correct?


Sent from my iPhone using Tapatalk

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I leave sometime some of the sides for narrow bindings (e.g. 1.5mm plastic) and leave the braces just short of the ribs/bindings - heard some disconcerting stories about guitars drying out and the braces pushing the bindings loose.
Not sure about how much truth is in them, but better safe than sorry.

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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.

I too have heard of that and wondered if it was a real concern. This is probably why I started leaving some side and lining material. That said, as long as the binding will cover the slot, you can still cut the brace short even if the slot goes through. I suppose that on the back and ladder braces, that would take away the lateral alignment, so you would need to be more careful with your centerline when you glue the plate on.

Also, if you are cutting all the way through the side you want to be careful about blowout.

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Bryan Bear PMoMC

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

Not sure if this would work for you, but it works for me because I only build 1 shape/size; I'd just have to make a different template for each size otherwise.

I use a plywood template to mark and glue top & back cross braces (ukulele). The template matches the heel and tail of my outside form, so brace location is always the same. I use the same template to mark the kerfed linings once the rim is on the form, and go from there. Basically, everything is registered off the template.

As long as the bindings are taller than the depth of the brace pockets

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Steve Smith
"Music is what feelings sound like"

I found this idea somewhere many years ago and it makes the marking task almost easy. Just position the top or back and hold in position with some weight and mark with this exacto saw along the sides of each brace. Remove the plate and cut the notches with whatever method you prefer.

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

That's exactly what I do too. And like Terrence I use a Dremel with the Stew Mac base to rout it out and it works like a champ. I use calipers to measure the depth of each brace end and adjust the depth of the bit and or adjust the brace end to fit and it's one stop shop deal.

I like to leave the side wood in place because with my method when gluing on the back I pull the sides in a little bit as I rope up that back and I don't want to accidentally pull it too tight, the brace end would hit the side stopping it right at that point. In fact I insert a 1/32in little shim at each brace end so that when I rout out bindings I can remove it and then I will have some room for expansion.

Otherwise no harm in removing the side wood as long as it isn't greater than the binding depth, at least I can't think of any problem in doing so.