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PostPosted: Tue May 06, 2008 9:02 pm 
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Cocobolo
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gaah Crack!!! I was trying to put in end block. I tried to spread the bottom sides to fit in the mold when I heard CRACK! [headinwall] Anyone want this guitar when I finish??? I will sell it at my cost :mrgreen:

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PostPosted: Tue May 06, 2008 9:09 pm 
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Koa
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Too late to help you now, but in the future you can stick a little scrap of wood shim between your sides and your form to support that grain until you're ready to glue it up.

Miek

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PostPosted: Tue May 06, 2008 9:22 pm 
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Old Growth Brazilian Rosewood
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Sorry about that but it got me to thinking........

I use side tapes that I install after the rim is in the mold and the blocks are glued in place. Why would one not be able to install the side tapes prior to gluing the blocks and placing the rim in the mold? Install them on each side right out of the bender.

It might prevent the kind of cracking that we see above?

Just a thought.


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PostPosted: Tue May 06, 2008 11:27 pm 
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Koa
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Wow, tough luck there Dave! It broke right along the edge of the mold didn't it....bummer... gaah

I glued my end blocks with the sides out of the mold. It seemed like a good idea to me. I didn't run into any trouble at all.
Why do the sides need to be in the mold for this operation? Can anyone convince me that they should be?

I like Hesh's idea of strenghening the sides BEFORE gluing the end blocks too. In my limited experience, I have to say I can't see any reason why you shouldn't do it in that order.

Dave F.

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PostPosted: Tue May 06, 2008 11:42 pm 
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Brazilian Rosewood
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...or use a taller mold? (the fracture line is telling)

Also, the sides were prolly too long. Plz don't ask me how I know.

Yes, you can repair this easily.

Mike


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PostPosted: Wed May 07, 2008 2:16 am 
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Cocobolo
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I can't say I've ever seen anything like this happen, nor had it happen to me. I can't even picture how it'd happen with a well bent side. Most sides I bend tend to put pressure on the waist bend when clamped into the mold and there's almost no spring from the tail end of the sides.

Seems that the obvious solution for future builds would be a taller mold (at least in the tail/headblock areas). You should be able to repair that, although it might be an idea to start with a new set of sides for the experience given you're so early in the build.

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PostPosted: Wed May 07, 2008 3:34 am 
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I don't like tall moulds, they make it more difficult to clamp linings and are more cumbersome when you glue the plates to the rim, trim the overhang etc.

Dave Fifield wrote:
I glued my end blocks with the sides out of the mold. It seemed like a good idea to me. I didn't run into any trouble at all.
Why do the sides need to be in the mold for this operation? Can anyone convince me that they should be?

One reason for gluing the blocks to the sides while they are in the mould is that it makes it easier to keep everything nice and square

I would repair the crack with either fish or hide glue, just make sure everything lines up perfectly when you glue and you should have an invisible repair. I have had similar things happen, oh yes…

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PostPosted: Wed May 07, 2008 8:19 am 
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Koa
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You're still early in the build process with this one. Toss the sides and start-over with a new set of sides instead of continuing and building a broken guitar. A set of mahogany sides will set you back what, 20 bucks at most?

this stuff happens. Every builder and factory has stacks of broken or messed up parts off in a corner somewhere.


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PostPosted: Wed May 07, 2008 8:33 am 
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Koa
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I agree with Grumpy on this one. Toss the sides and start over. I know that they can be fixed and it might be an interesting exercise to see if you can do it. However, I know that I've spent way too much time trying to save a piece of wood that should have been tossed. Since this is your first, you probably need the practice bending anyway. Unless you are using a piece of wood your grandmother left you in her will, the parts of a guitar are not all that dear. Don't get attached to them.


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PostPosted: Wed May 07, 2008 8:48 am 
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Mahogany
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I have had the same problem. I think that I was just not bending the sides well and trying to force it into the mold before it was properly bent. (I bend on a pipe rather than using a bending machine)

To help the situation a little while I was (still am?) learning to bend, I added a block of wood a couple of inches tall and a couple of inches wide on the outside of the mold at the tail block and neck block right where the sides come together. I did not attach it but made it so I could clamp it on and then take it off after the neck block and tail block were glued on. This was enough to support the sides right where they started to break and split. I had thought about making a taller mold but this solution seems to work well.


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PostPosted: Wed May 07, 2008 10:57 am 
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Cocobolo
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There is a saying that 90% of craftsmanship is learning to fix your mistakes. Dealing with something like this rather than just tossing it can be wonderfully educational .

Jaguars and pythons were playing in the branches of this tree when George Washington was worried about his acne ............[:Y:]

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