The Official Tube Bending Thread

Cool.
looks good!

and...Nice spinna, Yo.

 

Just cruz on over to You Tube. There are many mandrel benders on the market with plenty of videos to look at.

 

the best info i got when planing my mandrel bender came while i was at FAB TEC a few years back in Chicago, there were tons of beautiful benders there, tooling supliers, and i just went around looking and asking questions, one fellow took the time to listen to what i was building, we kicked around some different ideas and he did a few bends for me on his machine, a piece of 4"dia thin wall on a 3" radius, the tooling supliers gave me the run down on all the different types of mandrels, gave me catalogs, there were machines there makeing brake lines, cut, fittings installed, flared and bent as fast as the robot could take them away pretty much, i learned alot.

 

Wow, never would have thought to look on You Tube, thanks...

 

How about something cheap, simple, and cheap that could do 1"x1" square...say 16 gauge...something for us guys replacing wood in early chevys.

 

Glad I could help

 

1" x 1" x .065" is easy to bend, no problem. Just about any manual tube bender can handle that.

 

LOL, you caught that... we refer to the car it's on as "The Dub"... gotta pay the bills... and this one goes down on the bumpstops with 22's yo...

But to keep it on topic, I to have noticed that the Hossfeld does not like thin walled tubing, it bends the medium to thick stuff the best...

 

Let me know what material you are trying to bend and to what radius, and I can tell you how thick you need your wall to be to get a good looking bend.

 

I've always used the formula 3-1/2xOD for the Minimum Bend Radius of a round tube.
For example,if you're bending 1-3/4-in.-OD tube,Minimum Bend Radius=3-1/2x1-3/4 in.=6-1/8 in. so a 6 in.radius is close enough.
This is straight out of one of Ron Fournier metal fab books.

 

think 3/8" plate, 1" pivot bolt, and a few machined spacers.

The centre die is about 3" dia, out of some 1/2" plate, with spacers either side to suite whichever size RHS. (Note: if using 1" RHS, add about 1/16"-1/8" spacing to allow the RHS to deform.

bolt the stand to the concrete, and have a BIG lever.....









this made these bends....





Note: a larger dia dia is preffered if you want to minimise the distortion, cheap and simple to do, with plenty of easy options.

Cheers,

Drewfus

 

Do you sell the Tool or do you bend tubes as well?

Reason I ask is that I need one Hoop in Rollbar legal tubing.

I want to copy the Shape, Size & Radius of the Hoop that is on this car already.
But out of a material that will get me through Tech for Vintage Road Racing, and give more safety incase something would go wrong.

( there is a double Hoop on it right now, I want to put on a single...)

 

The Tube Shark bender we have sells a follower bar with "egg shapes" that turns out mandrel type bends according to their video. Heres a picture. I can't really say how well it works, or even if it works.
The bender itself is a nice unit though.

 

I think the .120 refers to the material you are required to use. They aren't going to drill a test hole in any of your bends.

 

The problem is not on the outside of the bends, the problem is that due to manufacturing tolerences .120" DOM tubing can get as thin as .108", if your building a roll cage for a drag car it will usually fail the sonic thickness test, so all the chassis people that build or sell mild steel roll bars or cages for dragracing use the .134" wall tubing so it will pass the sonic test, they check the wall thickness on a straight section.

 

Dose any body know where you can get .134 wall 1 5/8 or 1 3/4 locally in the San Francisco bay area. You can get it out of state but UPS can only ship 8 ft lengths. Not long enough for your average main hoop. I don't need to order a 1000 ft mill run!!!! Any help is apppreciated thank you.

 

Have you tried Van Bebber in Petaluma ? Not sure if they have it but they could probably get it for you.

 

Have you tried www.onlinemetals.com

 

Unfortunately, we do not do any bending for customers here. I do test bends all of the time to test out applications, but nothing like what you are looking for. I'm sure someone on the board has a simple rotary draw bender that could handle that application.

 

I'm familiar with the tube shark bender, but have not heard anything about that mandrel set up they have. Anyone ever used it?

 

Not sure on that one

 

Did you make that bender?

 

a friend did, tis rough and nasty, but works a treat, and easily modified to suit different size radius dies, and RHS.

Cheers,

Drewfus

 

Looks like it works good

 

Any other questions about tube bending or roll bending?

Let me know.

 

Here's a question for you, it's been mentioned before to try freezing water in tubing to keep it from collapsing when bending. Has anbody heard of cutting the water with soap to keep it from fracturing while frozen?

I watched a show where they were making trumpets (clearly thin wall tubing) and they used that technique to produce perfect bends.

Ron

 

Yes, they had an episode on "How it's made" on that same application. Sounds and looks like it works great for smaller, thin walled and softer materials.

I'm not sure how well that method would work for larger material. I have never heard of it working.

 

Alright ,who out there bends .083 chrome moly with there Hossfield bender ? If it can be done, what die set do you use and what radius is it. There web site says that the thinest it will bend is .095 on a 7 inch radius and that die set # is 28741. Thanks,Jim.

 

I'm not sure about Hossfeld specs, but the same "laws" to tube bending should apply for any rotary draw or rotary compression bender. Baileigh, JD2, Pro Tools, Hossfeld, Tube Shark...etc.

1 5/8 x .083 chromolly bent on a 5.5 CLR (center line radius) is a borderline application. Meaning it will bend very nice most of the time without wrinkling, but every once in a while it will give you problems with little wrinkles on the inside of the bend.

It is better to increase your CLR to at least a 6 or a 6.5. to keep this from happening.

Hope that helped, let me know if you need further information. This is a very common dragster application and I field these phone calls on a daily basis.

 

Once you get past the price of the equipment, a mandrel bender can let you do some really neat stuff.

One of our commercial customers is building a prototype hybrid car and recently hired us to bend and notch a bunch of frame tubes from 1.625"x.083" chrom-moly. We chose to use our mandrel bender because it securely clamps the tube in place, allowing us to get dead-nuts accuracy on our bend rotations and angles. Our Baliegh/RMD MB-350 has a 9 ft-long mandrel table and each of the long lower framerails started out 16 ft long. Once you make a bend on the mandrel bender, you can't reinsert the mandrel, so we needed to have our bend locations, angles and springback planned out exactly, otherwise we'd need to start from scratch with a new length of tube (this is different from a regular rotary die bender or a shoe-type bender, where you can re-bend to add degrees if necessary). We were able to bend the framerails out of single, continuous lengths of tube by starting in the middle, working our way out to one end, then reversing the tube in the machine and starting in the middle again.

Recently we also bent some 2"x.065" 304SS stair railings for a customer using the same machine.

We mostly use this machine for exhausts, headers and chrom-moly cages. Like mentioned in an earlier post, any application where you have a tight bend radius on thin-wall tube. The great thing about having a mandrel bender is that it allows you to make multiple bends on a continuous length of tube. This saves the cutting/splicing/welding that is needed when you are piecing together mandrel U-bends. Also, if you need, say, a 33-degree bend for a tight header or exhaust project, it's nice to be able to walk over to the bender and bend it up instead of having to cut into a 45, a 90 or a U-bend to make it.