Home made tube bender & dies

[Joe H]

Building your own tubing dies has been brought up quite a bit. I thought I'd give it a shot. The credit for the know-how goes to my dad though. He has quite a bit of sandcasting experience and has walked me through this so far.

I'm building a JD2 type bender. The parts are drawn up, and I'll be cutting them out on the laser at work. Hopefully I'll get that done this week. I was going to just buy dies, but my dad talked me into trying this. He has been wanting to pull out his furnace, and I've been wanting to learn sandcasting. At the very least this will be a learning experience, and some quality time with dad.

The die will be cast in two pieces and bolted together. I have gotten as far as making the pattern for a 1 1/2" die. This was suprisingly easy. I spent maybe 3 hours goofing off in the shop.


First I cut the radius' out of wood. The larger one is 3/8" thick and has a 4.5" radius. The smaller is 3/4" thick and 3.75" radius. These two pieces were glued together.

25904

25905


Then I made a bondo fillet around the circumference. I glued some 80 grit to a 1 1/2" tube and after about 5 minutes of sanding I had a pretty nice fit.

25906
25907

The pattern will be attached to the match plate on the right. On the left is the flask that will be used to make the mold.

25908


I still have to make a pattern for the follow bar, that should be super easy.
I'll post updates as I go. Hopefully I'll get to pour some aluminum next weekend.

[Broccoli1]

"Laser at Work"

uh... not really Home made is it then:D:p


Lookin' forward to the rest of the Photos

[Joe H]

Yeah, I guess the laser is kinda cheating.:D I just can't see myself hacking out that ratchet arm when it can be soooo easy and take 5 minutes.

I'm looking forward to finishing this. Hopefully the die will work out well. If not I'll just buy dies. This will be fun at the very least.

[whateg0]

I've never made any dies for round tube. I have made some for square but those are pretty easy since they're square. Because of this, I've been able to make mine out of steel plate. How do you plan to pull the two sides together? I have found that on square tubing, there's quite a bit of force outward as the tubing tries to squash. I'm just wondering, because that's always been one of the things I'd like to cast, if I ever get my furnace out and use it. I've been thinking of making it one piece via the lost foam or lost wax method.

Keep posting pics. I definitely want to see more!

Dave

[diverdale]

Holy crap dude....that's cool. I want you to make me one!! :D I want to see all the pictures...even the mistakes....assuming there are any.

Dale

[Joe H]

Hey Whateg0, my plan was to drill and tap one half for 1/4" screws, then drill and countersink the other half. I'll put several screws around the outside, maybe 1 1/8" from the edge. Hopefully that will stay together. I'm going to cast the follow bar as one piece, maybe that will help.

I'd like to see some pics of your dies. I have thought about square tube dies from stacked plate too.

Updates soon... I should have the bender parts cut tomorrow hopefully. We are swamped with paying jobs, so I have to be patient.

[whateg0]

Here's what I was able to locate. I'm not sure what I did with all the pics I took when I made it.

http://hobartwelders.com/weldtalk/attachment.php?attachmentid=18593&d=1153108626

I'll keep looking, or when I make it back to the shop, I'll take a couple more.

Dave

[Joe H]

That's nice! I'll have to make a few of those too.

I can tell you guys right now that this first die I cast is not going to work out right. Shrinkage is going to be an issue. The casting is going to be smaller than the pattern. I tried to come up with some calculations before I made the pattern but I got tunnel vision and had to stop before I passed out. The pattern was easy enough to make, so I will see how this first one comes out and go from there.

Once I've got it worked out I'll post the correct dimensions for the pattern, in case anyone else wants to try this.

[whateg0]

IIRC, the shrinkage is 2% for aluminum. The only real harmful (and only then if you consider it to be) effect is the bend radius will be smaller. You will probably benefit from the shrinkage in the bending area of the die. The sand cast surface (since it looks like you are using sand casting) will probably have a texture to it. You won't want that texture transferred to the material being bent, so it will need to be cleaned up. Here's where you may see an advantage. You can put some grit on some tubing and run it back and forth, just like you did for the pattern. In reality, you may want to find something just a smidge smaller, so that with the abrasive wrapped around it, you will end up at the desired radius.

Dave

[oldjeep]

Interesting project. I've heard of people making their own dies before, but usually with a piece of billet aluminum and a mill. I'm curious how the 2 piece cast die will hold up to the massive pressure exerted by the bender.

Make sure to keep posting pics!

[petersenj]

Looking good there. Make sure and post pictures.

I started the same project a long time ago and never finished it. I made patterns for 1 " tubing. I cut circles out of 3/4" thick pine and cut the radius with a router cove bit. Then I glued the two halves together and sliced in half to mount to a pattern board. I nearly took off my finger with the router and lost steam.

[Joe H]

Well, I didn't manage to make alot of progress this week. We're busy at work, and my son had baseball tournaments going on.

I did get a few minutes to finish sanding, and shoot some primer on the pattern. I also cut up a honda engine for donor metal.
25976

25977

[petersenj]

That looks like my scrap pile. What's left of it. Had to cash most of it in and it about broke my heart. Keep 'em coming.

[Joe H]

I cast both pieces for the die today. It worked out better than I expected. The second one came out nicer. I still have to make the follow bar, and the bender.:p

Here's pics.
26115

26116

26117

26118

26119

[Joe H]

One more.
26120

[whateg0]

Nice!:cool:

Guess I need to get some sand and start casting.

Dave

[Bob]

Looking at the finished home made die, it looks a lot like the "hicky" an electrician uses to bend conduit. Those come in several sizes. One of those might be good starting point for another way to make home made dies.
Bob

[whateg0]

Looking at the finished home made die, it looks a lot like the "hicky" an electrician uses to bend conduit. Those come in several sizes. One of those might be good starting point for another way to make home made dies.
Bob

Well, Bob, it looks like one because they are the same tool. The benders for conduit are much lighter, though, and they are sized for conduit, which IIRC, uses pipe dimensions, not tube.

Dave

[Corm]

Hey Joe, got any more progress shots? Are you finished with your bender? How did the die work for you?

Inquiring minds want to know....

[Joe H]

I haven't made any progress the past few weeks. :( No time.

It looks like I may get some time this weekend though. Maybe I can get some work done on this thing.