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I think it's time to build a bending machine
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Author:  Linus [ Tue Dec 09, 2014 10:38 am ]
Post subject:  I think it's time to build a bending machine
I think it's time for me to build a bending machine. I'm getting close to finishing my 4th build using sides that were pre-bent. And there is some construction going on in my building that is kicking up enough dust that I can't spray finish for a couple weeks so it's time to build jigs!!

Does anyone have a set of plans for a fox style bending machine they are done with, or aren't using at the moment?

Does anyone have any words of wisdom? Anything you wish you knew before you started? Wish you had done differently?

Thanks everyone!
Author:  arie [ Tue Dec 09, 2014 11:49 am ]
Post subject:  Re: I think it's time to build a bending machine
the only thing i wish i had done on my was to have put more visibility in the area of the waist clamp. the thing's kind big and gets in the way and makes it hard to see the bend. next time i make a machine i'm going to make the waist clamp area open for more visibility. and also a bit more width. 6" x 36" blankets aren't always 6" wide -they'll vary in width. go for thin spring steel slats as well. they return to their shape far better the those clunky stainless steel ones.
Author:  RustySP [ Tue Dec 09, 2014 11:54 am ]
Post subject:  I think it's time to build a bending machine
Never mind, please ignore this post, I was trying to send a message somewhere else.
Author:  James Orr [ Tue Dec 09, 2014 12:15 pm ]
Post subject:  Re: I think it's time to build a bending machine
I can say that a blanket and dimmer are well-worth the investment, as is a good thermometer. My blanket and dimmer came from John Hall. The harbor freight router speed control appears to be the same dimmer unit.

I use my multi-meter as a thermometer to measure the temp. The temperature probe is from Sears. I already had the multi-meter. The probe was around $10. The readings I get are quicker than an inexpensive thermometer.

My slats and the jig itself are also from John.
Author:  WudWerkr [ Tue Dec 09, 2014 12:24 pm ]
Post subject:  Re: I think it's time to build a bending machine
RustySP wrote:
Never mind, please ignore this post, I was trying to send a message somewhere else.


Ignored as per requested [:Y:]
Author:  Linus [ Tue Dec 09, 2014 4:36 pm ]
Post subject:  Re: I think it's time to build a bending machine
Can anyone share their experience with a Doolin style verses a Fox style bending machine?
Author:  WaddyThomson [ Tue Dec 09, 2014 5:38 pm ]
Post subject:  Re: I think it's time to build a bending machine
Doesn't take a fancy machine to get the job done. I just use a mold and the requisite blanket with slats. I use pieces of cut off 2x4's and clamps to accomplish the bend. Works just fine. I do wear gloves when working the hot slats, though I don't really touch them much with the hands, but can if I need to. It's a simple process.

Attachment:
P1080041 (Large).JPG
Author:  Terence Kennedy [ Tue Dec 09, 2014 5:40 pm ]
Post subject:  Re: I think it's time to build a bending machine
If you use a Fox style bender consider making the top removable. Makes it a lot easier to load the sandwich with all your spring clamps on it and remove the bent side, especially a cutaway.

I made my bender 10 years ago after taking the Fox course and made the tower too short so I had to make the top removable. It turned out to be an unexpectedly good feature.

Also devise a way to hold the lower slat down during removal so it does not to try to push the ends of the side out when you take it out.

Image

Image
Author:  Pat Hawley [ Tue Dec 09, 2014 5:52 pm ]
Post subject:  Re: I think it's time to build a bending machine
Terence,
Can you show your method for holding the lower slat down?
Thanks,
Pat
Author:  Terence Kennedy [ Tue Dec 09, 2014 7:21 pm ]
Post subject:  Re: I think it's time to build a bending machine
Pat,
I've just been putting spring clamps on the lower slat and connecting them with brown binding tape.

Image

For cutaways I used spring clamps for the lower bout end taped to something on the machine and have tried laying a very thin flat piece of ribbon over the cutaway area of the slat when the sandwich is clamped up and tying the ends to posts on the bender so the slat can't pop out. That works and although it is between the side and the slat it has not imprinted on the side so far. I've also used a block of wood clamped against the end of the cutaway slat so it can't spring out.

Image
Author:  Pat Foster [ Tue Dec 09, 2014 8:23 pm ]
Post subject:  Re: I think it's time to build a bending machine
Mine looks a lot like Waddy's only simpler.

Pat
Author:  unkabob [ Tue Dec 09, 2014 9:48 pm ]
Post subject:  Re: I think it's time to build a bending machine
My base uses two 150 watt light bulbs for heat and the molds fit over the base. The molds usually use three sets of eye-bolts and cross bars rotating on 5/16" bolts through the side of the mold. A heat blanket is a better system but I built the base for my first ukulele and I am still using it on number 21. I can also use the same base to bend matching cases.
Not the best system but it works .

Bob :ugeek:
Author:  Linus [ Wed Dec 10, 2014 1:55 pm ]
Post subject:  Re: I think it's time to build a bending machine
Waddy;

Your solution is elegant in it's simplicity.

WaddyThomson wrote:
Doesn't take a fancy machine to get the job done. I just use a mold and the requisite blanket with slats. I use pieces of cut off 2x4's and clamps to accomplish the bend. Works just fine. I do wear gloves when working the hot slats, though I don't really touch them much with the hands, but can if I need to. It's a simple process.

Attachment:
P1080041 (Large).JPG
Author:  WaddyThomson [ Wed Dec 10, 2014 7:47 pm ]
Post subject:  Re: I think it's time to build a bending machine
What made me go ahead and do it that way was Mario Proulx's YouTube video of his bending process. He uses a similar process to bend his sides. He actually bends with his gloved hands, and has a slat with holes in it to allow moisture to escape. It's simple, fast and if you have a space problem like I do, there's no machine to store when you aren't bending, which is most of the time. I mostly use a router speed control from Harbor Freight to control the heat. I have one of those controller thingys but have never gotten it programmed correctly and no one seems to know how.
Author:  Ed Haney [ Tue Dec 16, 2014 4:50 pm ]
Post subject:  Re: I think it's time to build a bending machine
I studied all the benders out there that I could find and settled on one similar to Mike Doolin's, but with some improvements. Compared to a Fox bender it has some nice advantages:

1. You can accurately cut sides to shape and length before bending (faster). The sides register square against a stop for repeatable bends accurate to withing about 1/64" length.
2. You are not handling a floating loose sandwich of multiple sharp spring steel slats, wood, heater and electric chord. This makes it safer and easier load wood. Everything is fixed and ready. Just load the wood only.
3. It is MUCH smaller (no tall screw clamp) for storing in a small shop, and the bender itself has storage in the top of the box and the electrics in the bottom of the box.
4. Easy to fix a thermocouple or two for accurate temperature control. Only one power chord for all components so no chords getting in the way. Timer automatically starts and shuts system down for safety after 17 minutes (or less) if left unattended.

I bend sides, bindings, linings, and peghead back strap on this one bender. I can pull it down and have any one of them bent in about 4 to 5 minutes from up on the shelf to beginning of cool down. I have never broken any wood on it. At GAL Mike Doolin told me that he has never broken a side on his. The spring loaded slats pull the heater tight against the wood for good heat transfer.

Image

Image

Here are some padauk bindings with maple perflings on the bender.
Image

The mold just sits on top of the bender box and is easily replaceable for various guitar sizes.
Image

Here's a link to more pictures of my bender if you are interested.
http://s456.photobucket.com/user/SUGARL ... 9113743506
Author:  Terence Kennedy [ Tue Dec 16, 2014 5:16 pm ]
Post subject:  Re: I think it's time to build a bending machine
Nice!
Author:  Pmaj7 [ Tue Dec 16, 2014 6:32 pm ]
Post subject:  Re: I think it's time to build a bending machine
Ed Haney wrote:
I studied all the benders out there that I could find and settled on one similar to Mike Doolin's, but with some improvements. Compared to a Fox bender it has some nice advantages:


Do you take paypal? :)
Author:  Ed Haney [ Wed Dec 17, 2014 4:25 pm ]
Post subject:  Re: I think it's time to build a bending machine
pat macaluso wrote:
Ed Haney wrote:
I studied all the benders out there that I could find and settled on one similar to Mike Doolin's, but with some improvements. Compared to a Fox bender it has some nice advantages:


Do you take paypal? :)


laughing6-hehe Making fixtures and jigs is a fun challenge for me, and others I've met. If it was not fun, it is easier and more efficient to just buy them as you are jokingly suggesting. In the case of this bender, there was no source to buy one and I wanted the advantages it offered. It controls the temperature very accurately with all the parts in one simple box.
Author:  Pmaj7 [ Wed Dec 17, 2014 7:42 pm ]
Post subject:  Re: I think it's time to build a bending machine
Yeah, I have been thinking for a couple years about how to modify mine. I would like to see yours in action. Got a video?

Assuming, you put the tail in first, is the whole thing sticking straight up, and then you bend the lower bout and then the waist?
Author:  Ed Haney [ Wed Dec 17, 2014 8:51 pm ]
Post subject:  Re: I think it's time to build a bending machine
pat macaluso wrote:
Yeah, I have been thinking for a couple years about how to modify mine. I would like to see yours in action. Got a video?

Assuming, you put the tail in first, is the whole thing sticking straight up, and then you bend the lower bout and then the waist?


I don't have a video.

Yes, I put the big bout end (tail) straight up on the registration stop and tighten the end clamp down (at the chord end) to lock the side in place standing straight up with sequence of spring steel, wood, spring steel, electric heater, spring steel. Then start the heating blanket. Bend the big bout, then small bout and lock down the springs pulling the 3 spring steel slats, then bend the waist. This keeps the spring steel and blanket tight against the wood for great steel support and heat transfer. Yes, the small bout is bent and then wood is pulled backwards into the waist so that there is a lot of tight support for the final waist bend.
Author:  Tai Fu [ Wed Dec 17, 2014 9:40 pm ]
Post subject:  Re: I think it's time to build a bending machine
I want to build one of these:

https://www.youtube.com/watch?v=1sNMHdaJx5c
Author:  Barry Daniels [ Thu Dec 18, 2014 11:49 am ]
Post subject:  Re: I think it's time to build a bending machine
Ed, will your design work with a cutaway?
Author:  Ed Haney [ Thu Dec 18, 2014 12:30 pm ]
Post subject:  Re: I think it's time to build a bending machine
Barry Daniels wrote:
Ed, will your design work with a cutaway?


Barry,

I plan to do a cutaway on it. I believe adding one clamp with do it just fine. In fact, if you look at the big fox bender style in this thread above you see two large screw press clamps - one for the waist and one for the cutaway. This is a common apporach I've seen. I can simply add 2 additional holes in a cutaway shapped mold and add one more small clamp like my waist clamp to pull the wood into the cutway. So I'll bend, in order, the big bout, then small bout, then waist, and finally the cutaway.

By the way, often the small bout clamp is not needed since the springs pull the small bout wood tight against the mold. (Note that the spring lever arms are adjustable when needed for various mold sizes.) If the small bout clamp is needed due to some really stiff wood, then it is the last clamp tightened to pull the wood against the mold. It obviously has to remain loose untill the waist and cutaway are bent and tight in place.

Ed
Author:  Michaeldc [ Thu Dec 18, 2014 7:24 pm ]
Post subject:  Re: I think it's time to build a bending machine
Here is my bender. It's a cross between an LMI, and a fox style bender. The blanket, slats, and temp controller are from LMI. The thing I like about the design is that I can simply loosen a couple screws and adjust it to any form I want. I currently have 5 guitar shapes, and a baritone ukulele form. It works like a champ!

Cheers, M
Author:  Glenn_Aycock [ Thu Feb 19, 2015 11:20 pm ]
Post subject:  Re: I think it's time to build a bending machine
I've never used one of these types of benders, although I've seen commercial ones in the Taylor videos. I realize they are probably much more consistent, but how long does it take to bend a side? I recon it takes 30-45 minutes to heat my bender and bend a pair of sides by hand.
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