The Stovebolt Site Forums The Shop Area Engine Shop Bending exhaust pipes - DIY? Harbor Freight?

I've seen a hydraulic pipe bender at Harbor Freight for pretty cheap ($69), hand operated. Any one used one of these to bend up a set of exhaust pipes? How about stainless steel?

I figure my dual pipes are going to need 4-5 bends each, and would top out over $300 to have a perfessional do it. Picking up a welder this weekend, wondered if I should pick up one of these tools tooooo...?

-Boyo

Boyo, as an electrician I machine bend pipe all the time. It requires basic geometry,and some trial work to establish radias take up and gain.Those inexpensive benders may work or they may wrinkle the pipe depending on the bender design and ductility of the steel, they are generally designed for crude bending.I have seen muffler shops do a terrible job, crushed pipe on the bends etc.To made a proper 30-90 degree bend on thin wall pipe,the bender must have a bending shoe and a follower , both of which have rounded sides to prevent the pipe from distorting.Most of these benders are for heavy wall pipe ,schedule 40, which need no additional support. Check the machine out closely before buying.

You could also buy mandrel bent sections and weld them up. You get more flow that way, tubing benders tend to restrict the diameter of the pipe on the corners, giving a double whammy in flow loss.

WE CALLED OURS A PIPE CRUSHER. 'CAUSE EVERY TIME WE WANTED TO BEND A SECTION OF EXHAUST PIPE IT WOULD CRUSH THE TUBING FLAT WHEN IT WAS ATEMPTING TO CREATE A BEND. (I WISH A HYDRAULIC MANDRAL EXHAUST TUBING BENDER WAS AFFORDABLE).

Hmm...too bad. Thanks for the input though!

Those mandrel bent pieces seem to be $20-$30 per corner, so looking at $200 for corners alone, plus straight pieces.

Might be best to let a perfessional handle it after all!

-Boyo

The Harbor Freight bender is good for bending stuff like black iron pipe or galvanized pipe or mechanical tubing with at least a 1/8" wall thickness. I used mine to bend up a frame for a small down rigger for shrimping and plan on using it to make a homemade gokart frame for the kids this spring. Better to find a good exhaust shop that you can drop the truck off at and bring back if it rattles or leaks.

This is a Greenlee Quad Bender, about 6000 bucks, bends electrial conduit ,thin and heavy wall up to 2 inch (2 inch conduit is about 2-1/4 od).I have used these to bend conduit for use on exhaust systems,with the contractors permission of course, lol. Thin wall conduit is galvanized inside and out, similar wall thickness as exhaust tubing.But the bends are too large of a radius for close quarters. Exhaust tubing generally kinks in these machines , just not ductile enough for the machine.. [img]http://www.toolup.com/images/product/Greenlee/Regular/854.jpg[/img]