Author Topic: Tubing thickness?  (Read 5120 times)

Eitek1

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Tubing thickness?
« on: May 25, 2016, 05:52:45 PM »
Anyone know the thickness of tubing used for the frames? I measured .080 but that seems to be an oddball size.

whoever had the simplex before I bought it used the crash bars at least once and it shows. I'm going to cut off the bent bars and install some new bars.

« Last Edit: May 25, 2016, 06:06:28 PM by Eitek1 »

ndian22

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Re: Tubing thickness?
« Reply #1 on: May 25, 2016, 07:09:16 PM »
Material matters more than thickness. DOM tube is used in most high quality racing builds but is expensive. DOM in .090" minimum though .120" wall is mo' better & higher still in price. Mistakes on bending aren't cheap. I've been twisting steel for 50 years so take all this with a grain of salt. We all have to make our own mistakes. Rick C.

Eitek1

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Re: Tubing thickness?
« Reply #2 on: May 25, 2016, 07:15:58 PM »
Thanks. I was going to use a few sticks of conduit to make sure I have all my bends right before I bend the real thing for that reason.

I'll find some .090 since it's pretty close to what's already there.

Ricks

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Re: Tubing thickness?
« Reply #3 on: May 26, 2016, 06:37:28 AM »
1 x .083 DOM is a very common tube size.  That is the size I used to build my 3 wheel tribute truck.  When I measured the tube frame on that bike, I came up with .065 wall from the factory.  I decided to use .083 as the length of the truck is much longer.
Rick

kartjockey

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Re: Tubing thickness?
« Reply #4 on: May 26, 2016, 10:17:49 AM »
I agree with Rick

ndian22

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Re: Tubing thickness?
« Reply #5 on: May 26, 2016, 10:18:44 AM »
Local distributors kinda dictate the "exact" size available & pricing ...especially on small quantities.  DOM tube variations of a few thousandth inch are in the ball park. New DOM tube of equal wall thickness is so much greater strength than original tube used on classic era bikes.  Hope you have access to a good mandrel "tube" bender for the job.

 Rick C.  

ndian22

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Re: Tubing thickness?
« Reply #6 on: May 26, 2016, 10:22:18 AM »
Sorry should read "a few ten thousands of an inch difference" RC

Eitek1

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Re: Tubing thickness?
« Reply #7 on: May 26, 2016, 04:46:51 PM »
RickS, it looks like you are right .083 is pretty common. I looked around online and didn't see it immediately so I jumped to a conclusion about availability.  I popped the plugs off of the end of the frames on the rear dropouts and measured there. It's very possible that the several layers of paint and slight bit of grime added a few thousandths to the measurement. I didn't sand it prior to measuring.

I've bent plenty of conduit and tubing in my days but I think this is going to be a different animal. I was at work thinking I'll just measure the distance between the bottom "legs" where they are the closest and from there I can figure out the angle that I have to turn my crash bars when I bend the bottom 90's so they fall out right.  I didn't notice at first that the bottoms of the crash bars where they weld below the foot pads are two different lengths and appear to be at two different "elevations".

This is going to be a bit challenging to get right the first time. I have a buddy that has a mandrel bender he said I could use. Hopefully I get it right the first time.