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Hi

I recently bent these Cherry sides, these are my first sides that I have bent. I can get them in the mold but I have to use spreaders to get them to fit flush, there is quite a bit of tension in them.

The pictures shows inside and outside the mold, woud you say that the amount of bending is normal and I am unlikeley to get them any better ?

John

maybe tweak the waist on a pipe .. the bouts are fine .... but they go in, so its not that bad at all

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I Tony that's was I was thinking, I don't have a pipe set up, something else to put on the never ending wish list.

The charcoal starter/ muffler pipe benders are really easy to make and less then $20 in parts. Both of my 2 guitars built were much worse then that going into the mold, so while not ideal, it is still workable.
Rob

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the sets will settle in eventually. You can dampen them with water and set them in with the spreaders. I don' think it will be that big a deal.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

A piece of steel or aluminum pipe about 2.5 or 3 inches in diameter and a propane torch. The flame into one end of the pipe. Don't use galvanized pipe.
Tom

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A person who has never made a mistake has never made anything!!!

Or a pipe with a heat gun. A wad of tin foil stuffed in the other end to control the heat works well.
No need to spend more than $20 for a very adequate hot pipe

Looks like they fit ok.

After your sides and spreaders are in the mold, you can use these to keep everything from scooting around in the mold. Three or four on each side, above and below the mold. Just knock 'em off after the top and sides are on.



Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

Hi Pat , I can't make out what these are can you provide a little more detail?

Thanks

John

John,

The sides might want to move up and down in the mold, like when you're profiling the sides, so these keep that from happening.

They're just some scraps stuck on the sides. Usually I use broken off pieces of kerfed lining, but just about anything would work. Also, if you take the mold off for some reason before the top and back are glued on, these will locate everything properly when you put the mold back on. I use hot hide glue, so I can just rub them around a bit on the side, and they stick right away, but Titebond or similar works, you just have to clamp them while the glue dries.



The end of my last post should have read, "Just knock 'em off after the top and back are on."

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

Nice idea Pat.

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Steve Smith
"Music is what feelings sound like"

Great idea Pat. I've been toying with some sort of Rube Goldberg contraption involving magnets, but your idea is elegant and simple.

Bob

That's why it took years to think of it.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

That's a good amount of springback, but I've seen the guys in the McPherson shop force much much worse into a mold and make it go. My molds are over compensated so they almost always overbend very slightly but that's how I like it. You'll be fine.

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John Mayes
http://www.mayesluthier.com

Do you put them top and bottom ? J

I have had it in the mold for 48 hours and have spritz it a few times with water. So far so good

John

Yes

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formerly known around here as burbank
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http://www.patfosterguitars.com

Yes

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formerly known around here as burbank
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http://www.patfosterguitars.com

Great thanks

John

Has anyone tried to just lay a blanket and slat over a pipe of smaller diameter then the waist and then just touch up the waist on it? It works on the bender form seems like it should work draped over a pipe. Or what if you put the side in the mold and put the blanket between the waist and spreaded and slat and did a quick touch up? Just a thought if you don't have a pipe and have a blanket.

I bend sides in the mold now, using the 'cutout' from the mold as a pressing/clamping caul. It works well.
I screw the two halves of the mold together for bending, then separate them and use in the usual way.
http://www.youtube.com/watch?v=gDQs4rnLbZU
For a touchup you could just 'pad out' the waist a bit on the mold and then bend with blanket and hand pressure (gloves,blocks of wood) to put in a bit of overbend.


Cheers
John

Most people seems to have issues setting up sides to a mold. The easiest way To get a perfect fit won't require 3 spreaders but just 1. When I trim a set I want to see the side set try to come off the waist as I close the mold. You want to match the length of the mold to the side length. To assure this trim the side about 1/8" long to the side of the mold Then as you apply pressure with the spreader you can see the side actually conform to the mold. You may have to tweak the sides to get the perfect fit but it won't take much at all. You may be surprised at how secure the set fits in the mold and how stable it becomes.
Some one out there will say this stresses the wood . With a proper spreader it won't . Check out this video. In 6 years of this technique I have yet to crack a side and I get perfect replication of the mold shape.
http://www.youtube.com/watch?v=QYHPCeVRUA4

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

The other thing that will help is getting your neck block, heel block, and linings installed....

You will be amazed at how much more rigid and stable the structure becomes once you get that stuff in....

Pat -- Yep.. Exactly what I need.. Next build is going to see those itty bitty blocks... Sure enough....

Thanks