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I am working on my first guitar. I'm building it from a serviced LMI OM kit. When I got the kit, there was a sticker on one of the sides (which were bent by LMI) saying, in effect, "Put these sides in your mold right away to minimize springback." So I built a mold to the plan that came with the kit and I have the sides in it.

My question is this: How well are sides supposed to match the plan/mold? The sides as I got them don't conform to the mold, even with three spreaders in place. There are gaps of about 1/8" inch between the sides and the mold below the waist, for example. Do I need to set up a hot pipe and touch them up? Or do I just squeeze them in as best I can and call it good enough?

Thanks for your help.

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John Cavanaugh
Saint Paul, MN
"What could possibly go wrong?"

I'll give you the voice of INexperience...it's fine the way it is, not
conforming perfectly to the case. I just glued on the top of my first
acoustic (I mean I *just* walked out of the shop), and those sides didn't fit
the mold right. The problem I had was that after I glued on the neck and
tail blocks, if I took the sides out of the mold, the waist would spring out
and look more like a dred than an OM. My answer when gluing the top
on was to use a bar clamp to hold the waist in until I got a couple of
spool clamps on and then I was able to remove the bar clamp.

So, if nothing else, an encouragement that it can be done...

I just finished a StewMac kit, and I'd been working along side a fellow building an LMI OM kit, same as yours. In neither case did the sides match the plan. Ideally, if you have the ability, use a hot pipe to bend the sides to a more accurate representation of your plan. It'll make the sides spread into the mold better, and if you don't use a mold (I didn't, I used a basic workboard) and glue the neck/end block outside of a mold, it'll make that a bit easier too.

They can probably be "squeezed" with only a little additional aggravation, but touching them up on the pipe will only take about 5 minutes a side. No big deal.

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Eagles may soar, but weasels don't get sucked into jet engines.

I would do a little tune up on the pipe bender and try and get it to fit the mold myself. Kind of tricky though with your blocks already glued and in place. I have never built from a kit but I would assume that most everything in the ones I've seen is precut and I would assume the mold plan is accurate to those specs.

I use a Workboard and spools as my set up for glueing the tail and head blocks as well, I find it easier.

Mike

[QUOTE=MSpencer] I use a Workboard and spools as my set up for glueing the tail and head blocks as well, I find it easier.

Mike[/QUOTE]

Agreed. I bought the John Hall 14-fret dread mold, which is awesome, before I bought the StewMac kit...but the two weren't a close enough match (wasn't supposed to be). So, I chose to build on a workboard and it was great. After that decision, I personally see some benefit to the mold, mostly to hold the sides perpendicular while sanding, but nothing that would "require" it. Nothing at all. In fact, in John Mayes' building DVDs, he free hands gluing the neck/end blocks together. Hard to argue with his results.

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Eagles may soar, but weasels don't get sucked into jet engines.

     using a mold allows a littel fudge factor to a degree. LMI and Stew Mac while based on a Martin design they may have the deminsions off just a tad for legal reasons but that aside a mold is the actuall shape desired.
      The sides will be set into the mold. If a set is long it needs to be trimmed. If short you can make up some difference off the tailpiece.
    Ideally you want the sides to be tight at the critical areas. The areas that I am most conserned about at
Neck area , the upper bout and waist. ALso the lower bout. if a set is way short I have shimmed out the tail so I could use the set.
The more you build and the better you get the more you can hide the mistakes. Though in reality we pros never make mistakes.
     Learn as many ways to do the same job , you never know when you have to change your technique
john hall

John:

I'm elated to hear you say that. The tail on my guitar, after I re-bent the sides, missed by 1/2 an inch in the mold. I used it anyway, knowing I'd have a fudge factor in the endgraft. It was close though!

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Eagles may soar, but weasels don't get sucked into jet engines.