Mandrel tubing bender-can it be home built?

Just wondering, can a mandrel tubing bender be home built with a semi-reasonable chance of having it work when done? I have looked on the net, but can't find any info at all. To tell the truth, all I have ever seen is the typical muffler shop type that sqeezes the bends on the inside of the curve. Maybe I'm just hopin' too much?

 

yes,

I'm sure I've seen it somewhere..?

it was not much more than a lathe turned steel egg on a rod that was held inside the tube, right at the bend on a basic bender
sound familiar to anybody?

 

I googled it and found this thread at metalmeet.com for what it's worth:

http://www.metalmeet.com/forum/showthread.php?t=1986

There's a diagram of a bender about the 4th post down.

 

I remember that. It was an old guy posting pictures of his dragster he built. Made the bender from scratch. It was posted here, but it was from some other board.

 

http://www.blindchickenracing.com/Tools/Tube%20Bender/Tubingbender.htm

try eBay for lo buck plans too...

 

http://www.lindsaybks.com/prod/index.html

 

not sure if this will help, but a few benders/builds from another board:


http://www.pirate4x4.com/forum/showthread.php?t=415304

http://www.pirate4x4.com/forum/showthread.php?t=343427

http://www.pirate4x4.com/forum/showthread.php?t=185940

http://www.pirate4x4.com/forum/showthread.php?t=376183


there's a plenty more where these came from.

 

You could build a bender, but in my opinion its not worth the time it would take to build one when you can buy a great bender for reasonable money. The expensive part isn't so much the bender, its the dies.

And even if you built your own bender, you'd still have to buy dies from one of the munufactures anyways, as 99.999999999999% of anybody doesn't have the tooling and machining skills to build their own dies.

I have a Pro-Tools 105 manual bender http://www.pro-tools.com/105.htm. The bender itself was about $300, plus I added the degree wheel and stop for repeatable bends. Even though I COULD make one, you couldn't pay me enough to take the amount of time it would take to build one.
And you can get one complete as a package with your choice of a die ready to use for $635

And really you don't need a lot of dies for most of what you do to build a car. Really my 1.75" round tubing die is the one I use most of the time.

I don't use the bender everyday, but its one of those tools that when you need it man is it nice to have. But some things are just better of to buy in my opinion

 

i went through the same dilema, wound up buying the exact set-up that dodgerodder has...Pro0Tools 105 with 240* 1.75 die, degree ring/stop. well worth it, since the closest one that i had access to was an hour away (that makes for costly mistakes)

but if you have the time, and resources...

 

Here's an idea that I've thought about, but haven't tried.

McMaster-Carr has aluminum cylinder samples in various diameters and around 1" thick. You could drill a hole through the center of a number of these, and then thread some copper wire through the holes to string them together. These would then work like a flexible mandrel, supporting the tubing as you heat and bend it.

Does that make sense?

--Matt

 

I built one for rollcage tubing. I bought a 200 dollar die and built the rest out of scraps. Mine looks similar to the $500 one that Speedway sells.

 

Don`t know what your trying to do , but a mandrel bender runs into some money! Theres a shop in Topeka that just bought a mandral bender if you need some tubing bent. You know the old guys use to fill the pipe with sand & cap the ends before you bend on a push/ pull bender to keep its shape!

 

When I'm done with the roadster, there are few tools I want to build.....maybe a tubing bender......

There are about 3 good sites on this...here's one and I think the others have been posted. I could only find this one, the rest are at home....

http://metals.about.com/gi/dynamic/...cing.com/tools/Tube%20Bender/Tubingbender.htm

EDIT: oops, already been posted too.....there's one more, but like I said, I don't have it here...

 

What I had in mind was the ability to bend exhaust tubing. I mess around with enough dumb stuff that it would really be handy. Example: 750 Honda chopper, I want custom pipes. I'td be nice to be able to bend handlebars, headers and other pipes for cars, etc. I wouldn't use it all the time, but it would be a nice addition to the shop. I have tried the fill it with sand thing before. It wrinkled a bit. At least it didn't collapse! I like smmmoooooth, flowing pipes, my eye gets offended at my own junk if I see compressed areas like you get with standard benders. I fear that the shop in Topeka would not want to mess with what I do, or would cost a bundle. I live in the KC area, not many places with a mandrel bender, and those with one have large set-up fees. I'm not opposed to having someone else do it, but I like doing my own stuff when I can. Then when it gets screwed up, I don't have to go very far to holler at the idiot responsible! I have noticed that most of the responses deal with non-mandrel benders. Some actually do a decent job, but I still have to work with the results to smooth it out to a level I can live with.

 

There seems to be some confusion on here.... there is a difference between "rotary draw" benders and mandrel. A mendrel bender has a flexible die that fits inside the tubing while the tubing is pushed through it. The die has to matched to the tubing size and thinkness (I.D. and O.D.). The die sets for mandrel are very expencive... I was quoted 40K for a used machine with no tooling. A rotory draw is a much simpler machine that is great for roll cages and most thick wall tubing (.090 and thicker). A JD2, hossfield, and others are example of this. The average price of a "rotary draw" is about $300 for the tool and about $220 for each die. The dies for "rotary draw" only have to be matched to O.D. on the tubing. The only positive of a mandrel is for exhaust and water flow since it does not kink or crush the tubing at all.

 

I`m like you, I figure that if I can do it, It will be done like I want it! Just thought I`d offer. The sand thing will work good IF you make sure that the sand is packed in tight!

 

employ Chinese slave labor at harbour freight.
Bench mount hand tubing bender $50
16 ton hydraulic pipe bender $180
10 ton hydraulic pipe bender $100

http://order.harborfreight.com/EasyAsk/harborfreight/results.jsp

 

I didn't catch that! Mandrel is different......I'd really like to see some hommade examples of a Mandrel bender.....THAT would be cool!

 

I guess I'm not certain why you need a Mandrel bender.I have a cheap manual bender and it bends super with 0 distortion.
Mine is the Williams Low Buck I think out of Florida.The secret is not to have to buy all the dies.
How does this work you say ,I'll tell you but don't let anyone else know.
Buy it with the 1 3/4 die or 1 5/8 whatever you will use the most . Take a piece of 1 3/4 tube that is .058 thru .065 thick about 3 foot long . Bend half of it in the bender and leave the other half straight.
Split the bent half in down the middle so it will fit the curved part of the die. Cut the straight piece down the middle and fit it to the straight part of the die. I actually welded tiny tabs to fit over the die ends to keep them in place. Install both halfs and now you have a 1 5/8 bending dies.
Now do the same with .110 to .125 tube and you have a 1 1/2 set of bending dies.
I went all the way to 1 1/4 with mine ,anything 1 inch or less I bend with the torch.
Now that being said I built several race cars with a Harbor Freight type bender with the bottle jack in the middle of and A-Frame. I would help it a little with heat on the top side ,but it did a graet job.
A mandrel bender takes a pretty good amount of power to move the inside mandrels. The tubing, while it is bending ,tightens up considerable .

 

gas4blood, you have four options for what you are tring to do.

1. buy premade mandrel sections and splice them together. Kovell doughnuts work too.

2. Use an arch style bender, to roll the tubing back and forth to desired shape.

3. Build wood dies and use a torch to strech the outside of the tubing while bending it.

4. Get a hold of a real mandrel bender to use it.

 

Hmmmm.... Measure diameter of your bent tubing with a caliper and you might be surprised by what you find.

That being said, That's a great idea, filling the pockets of larger dies with tubing to make them fit other sizes.

Chris

 

I have a tubeshark bender. I bought the I.T.S. (internal tube support) mandrel setup to go with it. The way it works it draws a machined plastic mandrel inside the bend as you are bending the tube. It would be easy enough to make the same type of setup for a JD2, or protool style bender. I am not sure if the new Tubeshark has a setup like mine, but they should have a website. I bought my bender 5-6years ago, before the bender was bought by ISCO, and they have redesigned the unit. I have used the I.T.S. very little, but I am usually bending .095+ wall tubing, and it is not needed for that type of work.

 

JOECOOL, does the tube try to grab the insert on the die? What are you using to lube the tube, and do not say KY!

 

JOECOOL, does the tube try to grab the insert on the die? What are you using to lube the tube, and do not say KY!
__________________
Jason

Good question. I was told when I bought my bender to always lube the tube when bending. It makes the pressure (my arm ) a lot less when I do . I just use a cheap lithium grease like comes in the tube,put it on with a chip brush.
The inserts are polished a little with a die grinder and a cloth pad,I do however have a tab on each end that keeps them from traveling with the dies.
If you use an tube that is electric welded and has a seam just make sure that part is in the half you throw away.
While were on this ,another thing that took me a long time to figure out is ,bend a tube and then mark on the die exactly where the bending starts and stops. It makes a good reference point. Also if you overbend slightly ,put some heat on the inside of the bend and it will unbend? (is that a word)

Maybe the next time I use mine I will take some pic's and get it in Tech week. Hope this helps.

 

here man, check this page out. I've used these guys before. Good stuff, cut splice. Just buy boxes of mistake bends from them any diameter. It's perfect for exhausts on bikes.

www.stahlheaders.com/Frame Tubing.htm

Unless you got several grand to drop to set up a mandrel bender, you better stick with buying bends.

 

What I've found is that sometimes, when humidity and gravity pockets are just right, I can bend tubing real nice, if it is fairly heavy wall, like handlebars. My problem really comes to the front when I try to bend thin wall tubing. The sand thing works, I hear, but when I tried it, it still wrinkled a bit on the inside. I filled it, pounded the fine grain sand in tight, then welded a plug in the ends. One end had been threaded, with a washer almost the same size as the I.D. of the tubing captured between two nuts. I figured I could tighten it up to increase sand pressure. Anyway, if it did any good, I could'nt tell. Those pipes are still on a motorcycle I sold and look OK if you don't look too hard. But every little screw-up I make is the only thing I can see when I look at stuff. I eventually get over it for the most part, but I still know. It is looking like the mandrel thing is a tough nut to crack.

 

BINGO!
http://www.jalopyjournal.com/forum/showthread.php?t=69958&highlight=mandrel+bender .

 

if anyone wants to do the sand filled pipe or tubing bends with heat you must be ABSOLUTELY!sure to use DRY sand as in bake it before use. Any moisture at all in the sand has the potential to turn your capped tubing into a pipe bomb!consider any sand thats not heated as wet it doesent matter if its stored inside if its been exposed to the air for any lenght of time it will pick up moisture from the air.I have seen a piece of waterpipe being bent in this manner split full lenght of the seam from cap to cap and opened almost flat in the center .luckily nothing turned to shrapnel in the shop just some flying sand and a big bang!I later found reference to doing this type bending in an old blacksmithing book and it states use ONLY hot sand for this reason.there are a lot of old crafts that seem easy but small details like this are lost over the years or when relating how its done they took for granted that people knew this because it was common knowledge then

 

I have a Tube bender I bought a few years ago from www.JDSQUARED.COM
They are in Florida.
It cost me abot a grand with three dies-3/4" 1-1/2" and 2"[round.
Also they have Rectangular dies.....
it is a real tool and will bend 2" black water pipe,but bends 16 ga tubing smoothly.....it has a 4 foot handle and is a manual bender.....

 

Hey, A/FX, this is exactly what I was looking for! And I can email the inventor if I have questions! Outstanding......Thanks!

Sorry for the informality, should I call you Mr. Comet instead?