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I’m in the process of building a bending form to bend the sides of a L-00. The last form I built I followed Todd Stocks tutorial and built s solid one.

For this one I’d like to try it with making the two sides and using either ½” aluminum tubing or wooden dowels to join them. I’m going this route in order to save cost and materials. My bender is a fox style bender with an aluminum support bar. I’ll make a dedicated waist caul for this form.

So my question is, when using the tubes to separate the sides, is there a theory behind where to locate them? Are there specific points in the body outline that they should go so that the side follows the bend properly? I’ve never seen a discussion that addresses this. I have seen vendors sell the tubes in sets of 6 or 7. Is there a strategic place to locate these tubes.

Thanks,

John

John,
I used alum flat stock I got at Lowes instead of alum tube. I just cut slots 3" apart to slip them in so they ended up flush with the sides of the mold and epoxied them in place. Works great and was easier in my opinion than drilling holes for tubes etc.

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Bobby Masten

I used 1/2" wood dowels on some of mine and they work fine, the steel or aluminum spacers I think are a throw back to the light bulb benders as the wood could burn. I clamp the 2 sides of the form together and drill the 1/2" holes with my drill press using a forsner bit. The edge of the hole at at the edge of the form, after all the dowels are installed joining both sides of the form, I make sure everything is squared up and wick some thin CA into the dowel to side joints. I have bent 4 sets on my 000/OM form with no problems, the dowels are cheap and easy to cut and use and should last a real long time.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Thanks Fred and Bobby. That is sort of what I was thinking Fred. And I have some 1/2" wooden dowels. I had thought about using aluminum bar, but I don’t quite have enough and haven’t come up with a really good way of cutting the slots accurately yet. Still working on the Bandsaw project (it is close).

So would the 3" spacing work? As I think this through more, the steel slat will still be riding on the plywood form. Structurally do these bars\rods impact the shape of the bend? I notice on the new LMI bending form that they are using 3 plates without bars or tubes. I guess the key there is to get everything squared up.

I usually overthink and over build (or under build) these things.

John: Why do you want to do it this way and not use a solid form..???
Tom

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

Actually the tubes are more for a separator that actual support. You can make it solid it won't matter much as long as your heat blanket is 5 watts per inch or more. The dowels should work but watch them for warpage. The tubes were used in the early days when aluminum flashing was used. With the stainless and spring steel slats , that pretty much took those out of the equation .

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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

Good one Todd!
I'll try it on the mould I'm building now...

Ok I'm in the middle of making my mold doing basically what Todd suggested. I'm at the part where I'm assembling, but had to call it a day. I'll post a pick when I am done.

Thanks for the tips.

John

The metal separators seem to make more sense for the light bulb method. BTW, those rectangular slots area neat idea.

However, if you a using a bending blanket, then the wooden form is best and easiest. Mine are made from 3/4 MDF (both sides) and poplar spars, assembled with glue and a brad gun. I leave all spars just proud of the curved edges. Then sand to shape. Once I have the form properly aligned in the bending machine, I trace the shape of the bending machine onto the form. I always screw the form to the machine.

Mike

I built my L-00 form using 3 plates with spacers. I bent my first side on it and it came put pretty good.









The second side is cooling on the bender. I’m keeping my finger crossed that it comes out as close.

Thanks for the tips everyone.

Y'all need to read the article in the latest GAL magazine that talks about improvements that Huss & Dalton have made to the Fox bender design over time.

Specifically, they show bending patterns with 4 plates separated by small wooden blocks, but registered with 2 metal tubes.
They also recommend doing away with the tower springs and replacing the screw-down adjustable waist block with a solid block of wood (one per guitar body shape).
There are other recommendations too.....but I'll let you go read the article yourself.
Not a GAL member? Why on earth not?!

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

Yeah, that adjustable waiste caul is crazy. I make wood cauls. Actually MDF... I used to not like MDF, but I keep finding good uses for it.

Mike

Mike,

I still need to renew the GAL membership for this year. I kept delaying it and now need to get in right before the end. I’ll defiantly take a look at that article.
My setup is basically a copy of Todd’s that I have picked up from past threads. I’m not using the adjustable shoe. I’m making a dedicated one for each form. Building one of these contraptions was a goal I set after I built my uke as part of the guitar build. Goal accomplished, now on to the building.

The tension spring did help keep things aligned. Since I’m new to this, the extra help relaxed me a bit. I took the second side out of the bender and it fit better than the first. I paid careful attention to how close the wood was conforming to the form in the second bend. The first side I let the bender do it’s thing and was more focused on the process of getting the wood bent rather than what was actually happening with the wood. In the first, I have a section that has a small knot and that didn’t shape as well. I’m going to try and reheat that one.

All in all the bender worked well and was a breeze.

John

Hey John, the sides look great. Glad the bender worked out OK for you.

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Jim Womack

"Be thankful we're not getting all the government we're paying for. "
Will Rogers

i agree that a solid form is best. that's what i'll build next.
in the meantime, i've found that i needed to add an extra support very close to each side of the waist. even with the spring steel slats, i've found that the side has a tendancy to cup, just a bit beyond the waist. it comes out with a bit of sanding. but adding a support and keeping the side flat to begin with saves time and just makes sense.
phil