1/2" pipe bender

By phobike Date 11-20-2007 18:10

Is there any way that you can send me some rough drawings with some dimensions and material list of this pipe bender? I am planning on building some pipe frame ATVs and this would come in handy!!!!

Wayne in Ohio

By aevald

Date 11-20-2007 19:25

Hello Wayne, it might take me just a bit of time to get something together for you, but I'll see what I can do. You do need to consider if you are going to use material other than sch 40 1/2" pipe that the inside bend radius might need to be increased to prevent wrinkling on the inside of the bend. Regards, Allan

By phobike Date 11-21-2007 00:24

I will only be bending 3/4 inch black pipe. I know that the die size will be different but all else should remain pretty much the same.

Wayne in Ohio

By aevald

Date 11-21-2007 01:06

Hello again Wayne, I will try to include enough information that you can make-up something that will work for the 3/4" sch 40 black pipe. This system will not bend a full 180 degree though, I myself have other die and bender combinations that I use for that kind of bending, they utilize a tried and true Hossfeld bending machine. If you get on the net you can probably google their site and see how it works if you're not familiar with it. Best regards, Allan

By phobike Date 11-21-2007 02:38

Allen,
I have looked at all of the bending machines online. I just can't see paying 4 to 9 hundred dollars for something that is so easy to build.

Wayne in Ohio

By aevald

Date 11-21-2007 08:39

Hello Wayne, I completely agree with the stinginess on the dollar for something that I can probably build (and usually do), or at least make an attempt at. What I was mainly driving at was for you to see the type of bending system that they use, and then possibly build the dies to use in their type of system, whether you buy one like theirs, or build one similar. I do have a Hossfeld bender at home and also one at the school. They are possibly one of the most versatile and oldest types of universal benders around and still being built very similarly to the original ones. When I bend using a Hossfeld I use a radius die and a following shoe, the radius die is made from a section of large diameter shafting with a 1" hole drilled through the middle for mounting and then the forming portion is machined on a lathe to match the diameter of the pipe to a depth equal to 1/2 of the diameter of the pipe, the following shoe is made from cold rolled rectangular bar stock and machined with a groove the length of it that is also machined with a radius equal to that of the pipe and also to a depth of 1/2 the diameter of the pipe. The length of this shoe is equal to half the circumference of the centerline of the diameter of the radius die, plus an additional 4" or so. With the following shoe pressing against the die at the point of bend these dies working in tandem encase the bend point in a rigid circle helping to keep from wrinkling the bends in the pipe. Here again, I'll see if I can come up with some pictures to show this better when I post the other information about the other type of bender. Best regards, Allan

By phobike Date 11-21-2007 16:24

Allen,
I am a welder now due to lack of job availability in the Patternmaker Trade. I was a patternmaker for Eljer Manufacturing Plumbingware Division for 14 years and my job went to China. I went to school for welding when they closed down.
I have access to lathes and the other equiptment that I will need to build the dies and I have a good welder at home.
Building the bender will notbe a problem.

Wayne in Ohio

By aevald

Date 11-21-2007 16:25

That's super Wayne I'll try to give you the necessary information for you to proceed. Regards, Allan

By aevald

Date 12-03-2007 21:55

Hello Wayne, I'm sorry for the long time in getting this done. I have included a couple of sketches that I believe explain the construction of this bender a little bit better. I have not included a bunch of dimensions as you will be modifying this somewhat to allow for the 3/4" pipe and also not knowing what sort of porta-power cylinder selection you have available will change dimensions. Most of the link bars and other parts can be fabricated from 1/4" M.S. flat bar or sheared plate. The round die can be made from either burned out plate or cut from a piece of the appropriate diameter shafting. The sliding blocks, as I call them, were made from cold-rolled key stock and I got the forming radius cut into them by putting the two pieces together in a drill vise and drilling a hole of the diameter that matches the OD of the pipe, centered on the seam where the two pieces met. Everything is bolted together with nylock nuts to allow for movement. 1/2" grade 8 bolts and nuts, and then two removable 1/2" pins on the sliding blocks so that you can remove them after you have made the bend to allow for easy removal of the bent pipe. Hope this helps some. Best regards, Allan

By ctacker (****)

Date 12-04-2007 03:01

Hi Allen, hope your staying high & dry this evening, when doing a project like this, you really need to be sure everything is stronger than the anticipated loads that will be applied, I have seen a few good people get placed out of the welding trade by inadequate homemade devices failing, The one that really comes to mind is seeing a guy get every bone on the right side of his face broken and really screwing up his future! The press he was working on was built to the FC 2002 and was "welded as good as it could be welded"

Not trying to take anything away from anyone, just be sure you remember if it looks like it could give, it will eventually.

By aevald

Date 12-04-2007 03:46

Hello ctacker, thanks for reminding me of that. Yes, you are correct about the safety of homemade devices and stored energy in mechanical devices. The best advice I can give to anyone is not to trust any mechanical device with the possibility to injure you. I don't mean not to use anything, I do mean to carefully inspect the item and determine which direction things will be going should there be a failure. In the case of this bending unit, always standing behind the cylinder and not standing over, under, to either side, or in front of the unit will generally provide an individual with the best level of safety. Anything can fail, when using mechanical items understanding where the stresses are and the results of various failures with respect to direction of shrapnel, parts, and pieces will save anyone a considerable amount of grief. I would hope that anyone who uses a design for an item that I have posted or anyone else has posted will keep in mind the possibilities for injury that could result from interpretations of the design and purpose of these tools. Consider that these items are conceptions of individuals and probably not engineered and tested designs.
I watched a pressbrake operator bending a piece of 3/4" A514 8' long x 6' wide, when he made the first hit on the part to bend a lip on it, it snapped into two pieces due to being bent with the grain of the material as opposed to bending against it. Fortunately in this case everyone was where they needed to be and the only real result of this mishap was a destroyed part and ringing in the ears of anyone without ear protection. It wasn't an accident that this operator wasn't hurt, he knew and respected the possibilities of injury from failures in a situation such as this one and religiously payed attention to the possibilities of failure and what the results might be. I have worked around a fair amount of heavy equipment and have seen the results of pulling final drive sprockets off of crawler tractors. With the sprocket mounted on a tapered output shaft and a hydraulic puller attached, when the sprocket finally gives and comes off you will often times watch a 200 lb or more chunk of iron go flying across the shop. In this case you make allowances for it's flight path and be sure that no one happens to be in the area when the time comes. I have personally witnessed a number of different types of failures of equipment and associated hardware and I always try to understand the reason for the failure and the possible fixes to have prevented it. DON'T take safety for granted, take an active role in promoting it and keeping from becoming a statistic with regard to it. Thanks again, ctacker, Best regards, Allan Oh and by the way I'm staying dry, but my routes for making it to work are being compromised rather heavily with the H20 that keeps falling around here.