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so i've got my home made fox style bender up and running and am having a problem with the slats. i'm using lmi's sst slats and they're really thick. after bending a side they look like a spaghetti noodle and need to be straightened out. of course when doing so they are never quite flat and have developed some flat and lumpy areas that are transfering over to the side wood. this sucks.

some info:
-small slope style 3/4 guitar (like a little martin, lil' brat, yamaha fg junior, etc..) the sides could be walnut, mahog, wenge, or zebrawood and are .09 to .095 thick
-3 pc bending form six inches wide. (wood, space, wood, space, wood equalling 6" width)
-6x36 heating blanket with controller
-sandwich is: form, slat, side wood, slat, blanket

anybody know where to source sst slats that actually will go back to reasonable flatness so that i get good contact with the wood for each new piece? i'm not too interested in spring steel ones because of possible wood staining but i could be convinced.

thanks in advance.

Get the spring steel John Hall sells at Blues Creek .. and if its not SS, just wrap the wood in foil

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

Get the spring steel John Hall sells at Blues Creek .. and if its not SS, just wrap the wood in foil

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

John Hall at Blues Creek Guitars carries SS bending slats. I find they work very well.

Cal

I guess Tony beat me to it.

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Remember, there are no stupid questions, only stupid answers!

good! i'll contact him (i bought the blanket and controller from him) thank you!

as to the foil, i did initially use foil to contain the small amount of mist i sprayed on the wood. what happened was that there is some kind of oil on the foil i bought (generic 365 brand from whole foods) i assume to help in rolling the stuff. when hot this stuff burns and smokes and mixes with the moisture and makes runny stains on the wood. i could get lab grade uhv foil but it's expensive ($116.00 a roll) but it is totally clean -but i think a bit on the overkill side.

also when bending the walnut, the foil wrinkles embed into the wood and have to be sanded out -weird, but i assume that's because walnut is quite a bit softer then zebra, or wenge.

Don't want to contradict anyone here, however just to let you know there's more than one way (isn't there so often!)
I use aluminium slats -got to straighten them like your stainless, but it's really easy to bend, and they work fine as long as they are well supported (like your form). Aluminium is very heat conductive
Also they don't corrode, and I just use brown (wrapping) paper round the wood so they don't get stained with rosewood juice etc. and transfer that to the next set of sides. flatten them over the edge of the bench or stool.
Cost - nothing, got them from the scrap (got lots). I've heard of people on your side of the pond using old aluminium flashing?
Only thing I'm personally a bit wary of about the spring steel slats is when you take the sides out of the form after bending, you have a thin bent side which hopefully doesn't want to straighten, and 2 spring steel slats which definitely do.
One observation - John Hall recommended form, slat, side(brown paper wrapped), blanket, slat. That way the side is in direct contact with the heat. Suppose the heat gets into the side quicker.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

interesting. could be an alternative -thanks. as far as the slat thing goes i really do like having metal directly between the blanket and the wood. our sides are a bit narrower then the blanket and i'm afraid of eventually damaging the elements in the blanket with the sharp edges of the wood.

For a standard bend I put a spring clamp on each end the bottom spring steel slat and connect them with a long piece of binding tape before removal. That keeps it from springing straight when taking the side out. The top of my bender comes off too so I can lift the side straight out.




For cutaways I stick a piece of thin ribbon over the lower slat when I makeup the sandwich and wrap it around rope cleats on the bender. That greatly eases taking the side out. I'm a fan of spring steel.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Aluminum slats working depend more on the design of the machine . On my machine they won't last and you will most likely get cross grain warping . The slats do 2 things , most importantly they allow the heat to travel to the wood and 2ndly they support the wood when being pressed .
If your using a solid pattern the alum may work . Of course it will depend on the thickness of the aliminium. In the end it as long as you get the result you are looking for , that is what is important .
If you have city treated water , I found that a barrier may be needed as clorine in the water may react with some of the resins in some woods. I have seen Koa turn green .
Have fun that is what this hobby is about . And yes, there is more than 1 way to do almost anything .

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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

I do use stainless slats as Todd points out I prefer them as they don't stain or rust .

_________________
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