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Whenever I make a new mold I have a lot of scrap plywood I don't know what to do with. Any suggestions...

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

Seems every inside mold needs a matching outside mold.

It looks like you have the makings for a "block bending form" if you use a heat blanket. I try to make my bending forms from the off cuts of the mold. By the time both are trimmed and sanded they are about the right dimensions.

kindling?............

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jw ( o)===:::

We have a ton of those too. Usually they get turned into various clamping cauls, jigs or whatnot. Also we use them as backing boards to drill the tuner holes to prevent blow out, and for clamping on the neck. They get used 4 times then get pitched.

Can't help you, other than to commiserate. I save every scrap, to a neurotic level. It would be easy to overcome my illness and throw the whole scrap pile on the fire, but hardly a project goes by that I don't find EXACTLY the piece I need for a filler, shim, etc... Thus the pile grows....

My name is Dave F, and I'm a scrapoholic....

Haha same here! Even down to slivers of veneer sometimes

Sent from my GT-I9300 using Tapatalk

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"I am always doing that which I cannot do, in order that I may learn how to do it."
Pablo Picasso

https://www.facebook.com/FenskeGuitars

As said above, won't you need a bending form for that mold? Surely your saw kerf is thinner than the guitar's side would be so you should be able to get a good form out of this. When I do outside molds, I plan specifically to get bending forms out of them as well. I can't stand wasting wood.

You don't really want to be burning the urea-formaldehyde glue anyway, do you?

I too see a side mold/bending form combo there. I'm not even sure which half the OP was worried about wasting.

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Jim Kirby
kirby@udel.edu

I've got scrap everywhere too. It gets used. Plywood scraps are used for whatever until they are too small then they go to the trash. Solid wood scraps that are no longer useful go into my kindling bucket and help me start the fires in my wood stove during the winter.

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Steve Smith
"Music is what feelings sound like"

Why not neck and tail blocks?

Steve

I am kinda anal about making my forms perfect (probably stupid but I can't help it...), but I end up with scrap from my molds and my bending forms. Certainly, I use the off cuts for cauls and such, but the scrap does seem to pile up.

Steve - I can see using them for tail blocks (although I haven't in the past), but neck blocks? Have you done that? What would you do, glue them together to get a deep enough block? I keep using mahogany for neck blocks...

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

Make a solid body. Little bit of filler then paint.

Hey Steve, yeah, using them for neck blocks just involves further lamination. And to be honest, I haven't used them either, but I've been tempted. The stability would be superior to any solid piece of wood, I'm guessing.

Steve D.

I make my molds out of a medium quality plywood from the big box store - they call it sandply. Not something I would use in a guitar. I do use plywood for tailblocks but it is high-quality birch plywood.

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Steve Smith
"Music is what feelings sound like"

I've used glued up multi-ply (baltic birch) plywood with a facing of 1/2 inch mahogany and mahogany veneered sides, for neck blocks for bolt on necks. Using a 1/2 inch facing of mahogany allows you to chamfer the inside corners without exposing the plywood. If you glue up lengths and cut multiple blocks from them the "time waste" factor isn't too bad.

Steve Smith (there sure are a lot of Steve's around here...),
I also use the medium quality sand ply for molds. It's not bad and certainly cheaper than Baltic birch...

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

Most of my shop benches, shelves, etc. are made of sandply and a fair number of shelves in my house too. Nice stuff for that application, paints well and isn't too expensive.

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Steve Smith
"Music is what feelings sound like"

I use baltic plywood, and make my molds and the the bending forms from them as was suggested by a couple of folks above. I actually cut the plywood pieces on my scroll saw. Usually can cut a couple of pieces before the blade breaks, and get a pretty smooth cut. I have started using plywood for tail blocks, and also find that I can't seem to throw any wood pieces of any kind away.

You could make some neat guitar-shaped shelves using the cutoffs as end pieces.

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wah
Wah-wah-wah-wah
Wah

If you cut these correctly, and carefully, accounting for side thickness, blanket and slat thickness, then you've got bending mold parts. Work great in the Fox bender.

Edit: I've not been successful doing this. Those cutouts just end up in the scrap heap. The inside shape of the mold needs to match the the outside shape. Seems in the cutting I always err towards the inside and the result doesn't make the cut for molds. The good news is a good mold will make a LOT of guitars.

"Edit: I've not been successful doing this. Those cutouts just end up in the scrap heap. The inside shape of the mold needs to match the the outside shape. Seems in the cutting I always err towards the inside and the result doesn't make the cut for molds. The good news is a good mold will make a LOT of guitars."


You could fill in the divots with bondo and laminate a piece of scrap HPL on the face to correct inaccuracies.

The inside mold should be smaller than the outside by 2mm or whatever your target side thickness is, and possibly considerably more at the neck and tail, if you want to over-bend to allow for springback. There's plenty of room for saw kerf there, and then use a little Bondo if needed as Clay said.

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Jim Kirby
kirby@udel.edu