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When I shaped the braces on my top, I was fortunate enough to not gouge anything (actually had only a couple scratches!), but boy did it take some concentration and sweat on the brow. Does anyone use a shield of some kind for just such occasions?
The other question I have is about sides cupping after they`ve been in the mold for awhile. Mainly around the upper bouts, and not so bad they can`t be worked out later. So far, I`ve had it on walnut and pear sides. Suppose it`s the wood itself, humidity (constant 45% nowadays), or just the nature of the beast? I noticed this when I was scraping down the sides on my first after it was lined, braced and the back mounted, but it seems to be the same with the rest, too (just bent, no other work done).

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

For the braces, I just run some thick tape down each side of the brace. It's enough to prevent any small scratches, but if you have a big slip, it's not gonna prevent gouges or anything like that.

Sorry, I can't help with the cupping sides--I've never seen that yet. Maybe it is something to do with the pear wood. That sounds very uncommon once the sides have been bent.

John

John, I had considered taping up, but thought maybe the tape might pull up some of the wood when you peeled it up.-But then again, I don`t think you`d have to roll it down with a 90 lb roller, either.

_________________
Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

Coe,

I use tape also. The first masking tape I used did pull a couple of grain lines on my Spruce top so I switched to very low tack masking tape. The stuff I use now is purple and is actually quite thick, by tape standards, and I haven't had any problems since. It is about $5 or so a roll in my part of Canada. Also, I rough out the braces with small Ibex convex bottomed plane and just use a 1/2" and/or 3/4" paring chisel to get into the tight spots or to get the contour I am after. I use a Veritas low angle block plane to slope the tops of the braces. The planes decrease your exposure of the top to chisels and are really pretty fast. I follow this up with 80, 120 and 220 grit sandpaper.

Hope this helps!

Shane

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Canada

Yeah, I`m making the move over to finger planes, too. Made a few last night. That was a fantastic link! I was just sitting here playing "choo-choo" with them a few minutes ago.

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

Get some masking tape and tape it to your clothes, than remove it and tape it again on to your clothes in order to get some lint (or dust ) onto the tape....this way you'll take most of the "stickyness" out of the tape thus preventing the tape from pulling the fibers from the top. The tape will still be strong enough to stick to the top. Then remove it from the brace when you are done and tape it right back onto another one!

Hope that helps

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Hi Coe, can't help much with the tape, but as for the cupping with pear wood, was it really soaked when you bent them or srayed lightly? And how long did you let the wood get acclimatized to your shop temperature ? I am asking because i read here yesterday that we should let our wood rest for 12-16 weeks before building.

I hope this helps

Serge

Hi Serge, Yes, I did wet the wood probably more than I should have. Not soaked, mind you, but I did spritz it and let it sit for about 15 minutes before bending. As far as temprature, it`s been here in the warm part of the shop for about three months. Let it rest for 12-16 weeks? It`s been that long for the first set, and I bent two more about two weeks ago. I did bend one set tonight and didn`t wet it, just steamed it for about 20 minutes. Went really well. The cupping wasn`t really that bad, though. Just took quite a bit of scraping to get it "flat". 12-16 weeks...Gee, Serge, I reckon I only have about 20 more years `til the Good Lord calls me home! How am I supposed to get my million guitars built at that rate?

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

Pressure sensitive masking tape
Luigi

I`ve also been kicking around the notion of making a shield out of .030" plastic, slotting it to the width of my braces. That way I can use them time and again. Won`t work for the x-brace, though.

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

I use strips of posterboard laid or taped down next to the brace i'm working on. I make up a "set" when i start carving so I don't have to stop & cut more strips.
Posterboard is stiff enough to stay in posision & prevent dings from bumping the plane into other braces
You can finish sand quite agressively without wearing through the posterboard or sratching the top / back.
Cupping is a pretty common problem with some wood. The Zebrawood on my last guit cupped badly around the lower bout. I've seen Bubinga cup badly in the figured areas.
For what it's worth... After leaving the sides for a few months, the cupping settled out quite a bit.
I *think* that cupping can be minimized by using less water. A very light spritz & cook all the excess moisture out as quickly as possible.
I wrap my sides in alum foil. After having a couple of sides cup on me, I now slit the edges of the foil in several places to let the steam out quickly... so far, so good.
You might be able to pull some of the cupping out by increasing the height of your popsicle braces & firmly clamping with a full length caul on both sides. Worked pretty well on the Zebrawood.
Good Luck!
Dan
Daniel M38764.1595717593

I just play it dangerous and go real slow. And do most of the shaping on the sides of the braces with my IBEX fingerplane, which has exactly no little sharp corners. I probably should use some posterboard or something...

Why not shape the braces BEFORE they are glued to the back or top?

i find that straight grained quartersawn if just spritzed rarly cups but I have had issue with high figure cupping. The best advise I can give is do not remove from the form and slats to quickly. If the wood stabelizes in the mold sanwiched between the tensioned and clamped slats, will help reduce any chance of cupping. It seems logical that cupping has to be a moisture issue. I have taken a cupped set and steamed the cupped area and placed a slat on each side and clamped to my mold and set it aside for a week. This worked pretty good. the pain is that you have to work out one cup at a time to get it clamped befor the heat of the steam cools too much to do any good

[QUOTE=Dave] Why not shape the braces BEFORE they are glued to the back or top? [/QUOTE]

a valid idea, which I do on the top braces somewhat before gluing up. However, you will still need to remove some material to voice the top.

next time you get an x-ray taken ( like a chest x-ray) save the thing cause the material they use for those things is super tough and makes a great shield when working around braces, fingerboards etc to protect the top.

I have some 10 mil mylar I use. I also use it when filing frets at the extension. It would probably be a hard to find item out side of the engineering or sign making industry by you could go to a print shop and get 3 or 4 mil mylar and using spray adhesive, glue multiple pieces together. some thin plastic sheet would do the trick as well with some low tack double sided tape if you wanted to keep it in place easy.

Has anyone ever tried strips of aluminum flashing? You could tape them to the work surface instead of the spruce and is shouldn't slip. I serious slip could still cut through but most wouldn't. I doubt that the aluminum would even dull the chisel if you nicked it.

Sharp edges on the flashing can cause just as bad of issues.

[QUOTE=Robbie O'Brien] next time you get an x-ray taken ( like a chest x-ray) save the thing cause the material they use for those things is super tough and makes a great shield when working around braces, fingerboards etc to protect the top. [/QUOTE]

Ooo....I smell yet another (in addition to free gloves and syringes) benefit to my med-studenty-ness...

I always put some strips of brown binding tape on the corners of my wide chisel, this way its easy to get the bracest down to zero at the ends... I have never used something laying on the top, i always use a small Ibex for shaping and it has so smooth edges.

I like the tip about "dulling" the tape by sticking it to your clothes!

I just use scrapers. I put them down on both sides of the brace I'm working. Just move them about as you're working the braces and you should be fine. Saved myself some pretty nasty gouges for sure. Works very well for sanding as well.

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

I don't use any protective barriers myself just a lot of care!

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John Mayes
http://www.mayesluthier.com