stainless steel tube bending

[DoryLvr]

I am thinking of making some racks for my boat and have a question about bending the stainless tubing. Will a simple conduit bender work or is the stainless steel too tough to do that way?

 

[Captains Cat]

Tivo, I'm currently having some SS 1" bimini bows made that will replace the 7/8 aluminum. The guy I'm buying it from (20' section for about $80) is bending it for nothing, it's a pretty simple process if you have the right tools. Most canvas shops have them, I don't think a regular conduit bender will do it without the possibility of crimping it, it has a pretty thick wall.

Charlie

 

[DoryLvr]

I didn't even think about a canvas shop, good idea. That price seems pretty good. I am trying to make a roof rack and am looking to make the cross bars to connect to the factory installed roof hand rails. I have been looking at "off the shelf" roof racks for cars, but not sure how they'd hold up to salt water.

 

[Aurelia]

We have had a Thule rack on the roof for about 9 months and in the water the whole time with no issues at all. It does not have many parts to be affected by salt water and basically all of the components are at least solidly corrosion resistant as they are made to sit on the outside of cars for the life of the car. The only part in contact wth the stainless roof bars are heavily coated steel clips and they should give years of service before wearing enough to start rusting.

 

[Da Nag]

Will a simple conduit bender work or is the stainless steel too tough to do that way?

Disclaimer - I've no actual experience with the following advice. I just read up on it once upon a time.

From everything I read on this a while back - no, you can not bend stainless tubing with such tools and expect decent results.

See this thread from a while back - might be helpful.

 

[thataway]

The best results are with a roller hyraulic tubing bender. I have seen some canvas workers who have done good jobs with a conduit bender. Sometimes sand it put inside of the tubing to prevent it from deforming.
SS tubing is expensive--I always have it professionally done--the cost is not much in comparision.

 

[forrest]

They do make stainless steel conduit. It bends smoother than malleable steel. Some tubing bent on our conduit benders and some didn't. Probably depends on the grade of stainless and the hardness. Us electricians bent quite a bit of small tubing on large radius shoes because that particular Pepsi plant didn't want sharp bends that a tubing bender put on the tubing. If you have a scrap piece just try it and see.
Forrest

 

[Sea Wolf]

Bending stainless tubing can be really tough, depending on the diameter, wall thickness, and alloy.

7/8" and 1" are the most common for canvas work. Larger diameters are used for some rails on larger boats.

As Bob says, sand is sometimes used to prevent collapsing and promote smoother bends. Some really high-tech larger diameter industrial bending equipment puts incredible pressure inside the tube with hydraulic equipment to prevent collapse and deforming.

I had to bend a 1" fairly heavy walled tube into a moderate curve for an exhaust stack when I installed my Force 10 Cozy Cabin propane heater. I could not bend it in a 6' vice with several feet of leverage. Wound up making a form out of heavy wood blocks an d running over it with my van!

Joe. :teeth :thup

 

[geebee2]

I built a temporary roof rack using 3/4" conduit 3yrs ago.I used an aluminium sealer(Alcoa) on it and it still looks like new.I didn't expect it to stand up to salt water this well. It's easy to work with and inexpensive.There are some pictures in my album Lucky7's.I was able to bend 7/8" SS hand rail in our conduit bender.It's on my swim grid.

Glen

 

[Zricky]

Hi geebee2, that is a cool roof rack, can you give some detail/instructions of how to build one of these? Also can you take a close up picture of how you connect the rack to the boat. Thanks

Below is a picture of the rack in question

 

[DoryLvr]

GeeBee2, That is AWESOME! That is exactly what I want on mine. Would love to hear the construction specifics. How to drill the holes for the supports etc.

 

[geebee2]

Hi ZRicky & Dorylvr,

If you look at the next photo in my album you can see better how I attached the rack to my handrails with u-bolts.This has worked very well and you can remove the rack quickly and easily.I'm a machinist by trade and have acsess to a small machine shop.I started by removing the hand rails and placing oversized SS washers at the 3 points of attachment to spread the load. I used the conduit bender to form the top and bottom rectangles, 2 - 10' lengths of 3/4"alumium conduit bent into U's then tigged together. I then cut all the uprights and the longer pieces for the bottom. I ran an endmill into each end to machine a shallow crescent to butt into the top and bottom frames. It is important to keep all the uprights the same length and also the bottom stringers to ease assembley for welding. I polished all the pieces before welding. Then welded it up.The last operation is to fit and weld the legs on. I made them just long enough to have the rack clear the roof. They have a 1 1/4" pc. of alum. flat bar (drilled to slide over them) welded at 90 degrees to the hand rail and drilled for the U-bolt.

I hope this helps.I was unable to add pictures to my album tonite and my boat is stored for the winter. So I will try to get some better pics and post them.

This is low cost but labor intensive and is holding up suprisingly well.

Good luck.