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 Post subject: Inside Mold Offset?
PostPosted: Mon Oct 20, 2014 2:17 pm 
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First name: Alex
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How much offset do you guys/gals have from your bending molds to your inside molds? Bending slat+side= offset, or do you make it a little tighter for any spring back? Or just tighter at the head and tail blocks. Thanks, folks!

Alex

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 Post subject: Re: Inside Mold Offset?
PostPosted: Mon Oct 20, 2014 2:52 pm 
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Brazilian Rosewood
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About .100...


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 Post subject: Re: Inside Mold Offset?
PostPosted: Mon Oct 20, 2014 3:04 pm 
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meddlingfool wrote:
About .100...


Thats exactly what I have drawn out with my fancy offset gauge - a washer with a hole drilled in the rim!

Alex

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 Post subject: Re: Inside Mold Offset?
PostPosted: Mon Oct 20, 2014 6:44 pm 
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Brazilian Rosewood
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I bandsaw the outside mold and the block form out of the same pieces of plywood, and after sanding and cleaning them up with a router wind up with about .10 inch difference. I don't build in anything for spring back.


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 Post subject: Re: Inside Mold Offset?
PostPosted: Mon Oct 20, 2014 7:53 pm 
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meddlingfool wrote:
About .100...

That and I take about that much again right in the belly of the waist and fair the same head and tail to help account for any spring back.

Oooooo you're getting closer. Cool. Did you build a bender?


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 Post subject: Re: Inside Mold Offset?
PostPosted: Mon Oct 20, 2014 11:08 pm 
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Yup, made a bender last year with a MJ profile. Decided that I wanted to do an SJ instead, so I made a new form last week. I'll take a picture of it tomorrow.
I just got back from seeing Larry Coryell in Toronto in a trio with a local bass player and drummer. :D Just an incredible show. Whether on electric or acoustic he was tearing it up. Not bad for a 70 year old grandfather. I spoke with the bass player for a few minutes between sets, and he told me that they only rehearsed for about an hour today. wow7-eyes

Alex

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 Post subject: Re: Inside Mold Offset?
PostPosted: Tue Oct 21, 2014 10:37 am 
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Image

The new SJ form is all ply, the MJ is ply and mdf. I always have lots of sheet scraps to use up.

Alex


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 Post subject: Re: Inside Mold Offset?
PostPosted: Tue Oct 21, 2014 10:53 am 
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Brazilian Rosewood
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Looks good!


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 Post subject: Re: Inside Mold Offset?
PostPosted: Thu Oct 30, 2014 4:31 pm 
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Inside form done.

Image

Alex


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 Post subject: Re: Inside Mold Offset?
PostPosted: Thu Oct 30, 2014 4:34 pm 
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Antes parlour guitar bending form made from inside mold scrap.

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Alex


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 Post subject: Re: Inside Mold Offset?
PostPosted: Thu Oct 30, 2014 4:53 pm 
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Alex, remember with those inside tension blocks that you'll need to get them out of the sound hole (and your hand in there to remove them) so make sure you test them before going live (ask me how I know this.... :) )

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 Post subject: Re: Inside Mold Offset?
PostPosted: Thu Oct 30, 2014 5:08 pm 
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Brazilian Rosewood
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^


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 Post subject: Re: Inside Mold Offset?
PostPosted: Thu Oct 30, 2014 5:27 pm 
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Thanks for the heads-up Rod. The threaded rod and copper pipe are friction fit, so it will all come apart inside the box. I'll probably move the upper bout turnbuckle closer to the waist to accomodate the head block, though.

Alex

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