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are those forms with the light bulbs inside and the sheet metal covering the outside used to help the sides keep their shape after bending?

this website has so much info. i cant stop reading all of it. cant wait to build my first

 

Welcome to the forums. I agree with you opinion of the volume of great information here! Someone allot more experienced than I, will more fully answer your question I am sure.

Jerr6:

Well, sort of. Actually those forms - in the shape of the guitar being built - are used TO BEND the sides over them in order for the builder to obtain a specific shape (the shape of the form). Once the bend is complete, yes you could say that with proper care and technique the side WILL hold its new shape when taken out of the form. Some builders use very hot "pipes", and bend the thinned sides to the guitar shape by hand...it's an old technique, and requires much skill and practice. The "forms", or benders, is more of a mechanical aid.

So...yes, the form is used to bend the side to a specific shape, and the resulting bend maintains the new shape.

Hope that helps.

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

Jerr6 -

As mentioned above, these forms are actually the implement for bending. The original design was based on bulbs, but many of us have switched to using heating blankets - best source is our sponsor John Hall at Blues Creek Guitars - link above. The advantage of the blanket is that you avoid scorching on the inside of the forms, and you can also use a completely solid inside form (thus no chance of sags, etc), although I use the same form I'd use if I were using bulbs.

Search the archives for bending, heating blankets, etc. There is piles of information here.

Jim

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Jim Kirby
kirby@udel.edu

Welcome, Jeremy! If you're after guitar-building info you'll love it here.

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now known around here as Pat Foster
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http://www.patfosterguitars.com

Welcome, Jeremy
I still use light bulbs and it works ok, just slow. I bent a side yesterday and will bend the other tomorrow. After the sides are bent we place them in an outside mold to maintain the shape and hold the sides while sanding the rims and fitting/glueing the top and back. At least that's what I do, and it works well for me. Some day I will get a blanket for more even heating and much faster heating. I haven't scorched anything yet and my 150 watt bulbs are on for about 30-40 minutes during a bend.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

     If you are looking for a way to hold the shape after bending you can use one of 2 methods
1 the building form
2 cut a slot in a board about the same length your guitar would be. To that , in the waist area screw in a eye screw and attach a line with a loop in it , then you set the sides in the slots and run a dowel through the loop so you hold the waist in the same shape.

As for light bulb or blanket for bending I can tell you this
light bulbs do not allow you control of heat and you are relying on refractive heat. With the blanket you get contact heat and you can control your heat to the degree.
   This may not seem like much but condider that your cracking will be less that 5% with the blanket and about 10% with one. I bent over 200 sets last year with the blanket and only lost 1 set.
when I was using just light bulbs I broke a set about one in 10 to 14 bends.
they pay for themselves fast
john hall
blues creek guitars
check out the tutorials at my website for using a bending machine

thanks for all the help. it answered alot of questions.