Making dies???

Sheet Metal Fabrication techniques, questions and help. "Tricks of the Trade"

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tittlek
Posts: 42
Joined: Mon Jun 30, 2003 1:11 pm
Location: Lansdale, PA

Making dies???

Post by tittlek »

I should mention I been lurking here for some time and I am an absolute newb at metalworking, but I have learned a lot already just from this forum. I have a question regarding tubing benders and this seemed to be the most appropriate forum to ask this question. Especially since it seems there are a few other posts about making dies... albeit for a different type of machine. I should also mention I am the type of person that would rather build something (usually a tool) than buy something that is readily available from a retailer so that I can learn something in the prcoess. I guess thats what makes me a hobbiest [img]/ubb/images/graemlins/smile.gif"%20alt="[/img]

I have seen homebuilt tubing benders that cost their owners much less than if they bought one. With this knowlede in hand I was planning on taking a broken hydraulic shop press and modifying it to work as a hydraulic bender. I am basing the design on the "bow and arrow" style bender. The only thing I see wrong with fabricating my own bender is that I have no idea how I would make the dies needed to get the proper radius bend without crushing the tube. From what I have seen they can be made of either cast aluminum or iron. Also I noticed if one were to buy these dies they can run around 100 dollars a piece. Seeing as I have a limited amount of knowlege and tools would it be feasible for me to make my own dies or should I just bite the bullet and drop 100 bucks on a die to fit my homebuilt? Or Should I swallow even harder and buy an entire bender with a die? The reason I wanted to build my own is because I also have limited shop space and I figured I could rig my homebuilt machine to handle a few processes in the same floor space (pressing/bending/etc...)

I hope I am not asking stupid newb questions. I'm glad I found such a wealth of knowlege from such experienced metal workers.
Been you to have any spliff man?
Jacin
Posts: 1046
Joined: Sat Dec 21, 2002 12:14 am
Location: Near Cleveland, Ohio

Re: Making dies???

Post by Jacin »

I have both a Hydraulic pipe bender (bow and arrow type you describe) as well as the "hossfeld" type.

Make no mistake about it the bow and arrow type works great for it's intended purpose - and that's PIPE. It works decent to poor on tubing and certainly UNACCEPTABLE for most of the type of stuff I want to bend (chassis work).

The trick to a bender is controlling both the "stretch side" as well as the "compressed side" of the tube. The Hossfeld typ bender uses a "wiper" die that much like it sounds wipes across the outside of the tube during bending. Though this is somewhat shy of a full blown "mandrel type" bender - I will say the results are near perfect. For this reason I would strongly suggest building that type of bender. AS a matter of fact since Hossfeld's patent's have run out there are not only several "knockoffs" available, but I have also seen plans published on the web - heck maybe even here in the drop box - can't remember.

Now on the other hand I have also seen a variant type of press that uses a rolling die and long reciever- but by comparison I think the Hossfeld is far more popular - for good reason.

Back to the Hossfeld type......the "wiper" die has two distinct feed angles which I suspect gives it atwo stage effect when bending/feeding the tube - this is easier to see than explain - so I would suggest finding a buddy with one you can closely inspect. In addition the mating die (inside radius) is more effective if it has some "tooth" - this helps keep the tub in place and helps prevents wrinkling.

Your mileage may vary
tittlek
Posts: 42
Joined: Mon Jun 30, 2003 1:11 pm
Location: Lansdale, PA

Re: Making dies???

Post by tittlek »

Well thanks for the good advice. I had emailed Williams Low Buck tools asking a few questions about the drawbacks of the bow and arrow type bender but never got a reply.
I see you mention the hossfeld type bender as being the way to go but I am a bit curious as to a 3rd type that Williams Low Buck Tools sells. They just call it the Lowbuck Hydraulic Bender . From what your telling me it seems that this type also uses a wiper die. I'm guessing its sort of a variation on the Hossfeld.
Now that I know a bit more I am definately ditching the bow and arrow type bender. I am planning on doing some chassis work in the future and I don't want anything unsafe. I think I know the answer to my next question but I am gonna ask it anyway.

Which, between the hossfeld type and the low buck type, do you think is more versatile? I would like a bender that can not only do tube but flat bar or square stock. I'm pretty sure the hossfeld can do that because they seem to be the benders that decorative wrought iron workers use. However I'm also concerned about the force required to bend something with the hossfeld type. Finally back to my original question... How hard would it be to make dies for a hossfeld type bender? Is it a reasonable task to tackle or should I just buy the dies?
Been you to have any spliff man?
D_R
Posts: 297
Joined: Mon Feb 03, 2003 6:44 pm

Re: Making dies???

Post by D_R »

TittleK,

Go to toolsforbending.com

Look under "tooling" and you'll see some diagrams of benders.

The Williams bender you reference is not a bad type, Greenless also makes one in that style. No, these type benders do not use wiper dies.

The Hossfeld is the most versatile bender there is. It'll do practically anything related to bending from flat bar to tube. It doesn't do anything particularly well, but it does do everything. By that statement I mean it's difficult to get accurate bends at an exact location with a Hossfeld.
tcoe

Re: Making dies???

Post by tcoe »

Go to hobart welding site look under projects find list for tube bender. They have a company listed with the cheapest bender I have seen up to 1" tube. Dies are 60-90 and bender is 125-250 depending on size and type.
Greg_S

Re: Making dies???

Post by Greg_S »

D R, your comment "It doesn't do anything particularly well, but it does do everything." about the Hossfeld benders made me laugh so hard I almost tilted off my chair!
Oh how many times using mine have I thought exactly the same thing. A wonderful, wonderful tool that you couldn't get away from me for anything but it still has it's limitations to the class of work, especially if you want to do multiples.
I recently purchased a bending die I needed from them and I sure did wonder if it came from overseas. The 'odd' look of machining and the packaging using that stuff that looks like stringy toothpicks just screamed foreign. I have nothing else to base that suspicion on. It wouldn't allow bending a full 90 degrees because of improper machining so I emailed them and an engineer responded that it was operator error (me!) so I remachined it and I guess I became a better operator because it works now!
Jacin
Posts: 1046
Joined: Sat Dec 21, 2002 12:14 am
Location: Near Cleveland, Ohio

Re: Making dies???

Post by Jacin »

Hey Greg, I haven't had to do any repeat work with mine - just one off stuff. But I had wondered if the "degree wheel" is a worthwhile option. My buddy has one one his, but has yet to use it. I was contemplating making one, but wondered if it's worth the trouble. ANy thoughts???? Thanks!
Greg_S

Re: Making dies???

Post by Greg_S »

Hi Jacin,
This degree wheel would be attached to the part to keep it in plane while you bend? or are you talking about keeping score of degree of bend on the machine as you pull the handle?
Wasn't sure so I'll wait and offer my take on it after we carify.
Greg
Jacin
Posts: 1046
Joined: Sat Dec 21, 2002 12:14 am
Location: Near Cleveland, Ohio

Re: Making dies???

Post by Jacin »

Greg, I am fairly certain it bolts to the fixed arm and then indicates the amount of movement of the pivoting arm. I suppose the "springback" would be needed to be learned empirically - likely different for different alloys - ???? and or wall thickness' ???? I dunno

as I recall the degree wheel he bought was rather pricey of course that comes from a cheapskate <grin>
Skeeter5000

Re: Making dies???

Post by Skeeter5000 »

Hello Tittlek,

I have a 12 ton pipe bender I bought from Harbor Freight. This unit cost me about $70.00. It has worked for pipe and ridged conduit. I don't use it often but have it if needed.

Mine has done a good job on the things I have bent. This is the bow and arrow type referred to. This unit could be adapted to other things within it capacity.
Greg_S

Re: Making dies???

Post by Greg_S »

Jacin,
I would think a large degree wheel or something of that nature would be useful at times. To tell you the truth, I've always just 'sneaked' up and checked until I had the angle I wanted. At that point, I use an electronic beeper that came to life as a cheapo continuity tester for automotive work. I set it up so as I'm out pulling around the arm (a long way from pivot point), the beeper contacts come together where they've been set from first bend and then the audiable noise tells me when to stop. Crude but effective???
I use a degree wheel attached to the part a lot more often, so I can keep the next bend in the same plane as the previous bend. I use two versions, one is a simple platen welded on the saddle side of muffler clamps. To this I stick a magnetic level/protractor. The other is an aluminum plate with a radial groove cut in the face and a paper degree wheel. There is a small ball bearing that goes in the groove and all this is sandwiched with a piece of clear plexiglass. Gravity always has ball at bottom of groove which indicates the angle (or lack of) rotation. Got the idea from the exhaust automotive business I was once in. You can see one at any place with an older exhaust pipe bender. No doubt you've already seen one though.
If you want to make a fairly large degree wheel for the top of your bender on the cheap, I think my wife could cut you one out on her plotter. I haven't asked her but i do frequently volunteer her for the unusual (without asking first). Or maybe you would only need/want 180 degrees perhaps. It would be in vinyl and you could stick it to a piece of aluminum or whatever with a small hole tapped in top of your center pivot pin??? Just an idea on the cheap for you.
rodzilla
Posts: 2
Joined: Mon Sep 27, 2004 12:57 pm

Re: Making dies???

Post by rodzilla »

I can't remember what site i found this at but i have plans for the hossfeld type bender in both acad and jpeg format i will try to remember what site i got them at attached is a sample
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