Torsion bars

[Larryjb]

This is a little bit of a crazy question, but here goes...

Has anyone every had replacement torsion bars made up locally? I know I could get them from TM, but if torsion bars in general use the same type of steel, that means that the spring (or torsion) constant would be determined mainly by the length and diameter of the bar.

I'm hoping to save on shipping costs if something can be found locally.

[Bill]

Larry -

TM uses, and stocks, at least a couple dozen different torsion bars. Recently someone posted a link to a series of photos of a TM factory tour. One of the photos showed a big rack of different torsion bars. Check it out!

Bill

[Larryjb]

Bill,
I do realize I can get them from TM. I was curious if I could save on shipping, and also the exchange rate. I'm guessing it's not worth chancing.

[Bill]

Larry -

I understand, and I missed that point about your query. My bad.

Not being a metallurgist, I don't know how to make a torsion bar, but I'm thinking the steel is probably special in some way, so that it twists and rebounds, rather than twisting and taking a set. After all, the bar twists 90 degrees over an 8-foot length, and is expected to do this hundreds of times.

My immediate thought is that you have to tell the fabricator what you need, and I have no idea how to specify the performance (the strength, mainly). The fabricator is unlikely to give you a refund if you give him the wrong performance numbers.

Perhaps some of the scientists here on the board could offer suggestions.

Bill

[BrucePerens]

The Wikipedia article on spring steel lists several alloys. The heat treatment required is annealing during shaping, then hardening, then heating to about the Curie point for tempering. Sounds like a job for a specialist. You would not achieve your desired torsion on the first try. The specialists have a repeatable process.

[Larryjb]

Originally Posted by BrucePerens

The Wikipedia article on spring steel lists several alloys. The heat treatment required is annealing during shaping, then hardening, then heating to about the Curie point for tempering. Sounds like a job for a specialist.

If I were to consider this route, I'd only go with a company that actually makes torsion bars. I'm not even sure if there's anyone local here that does that in the first place. I imagine TM has their torsion bars made for them.

[momto4girls]

My curiosity is peaked. A long while back when I was still considering what type of travel trailer would work best for us, I watched a TM video (made by TM) which stated they've never had a failure of the torsion arm system--in the history of the company. I can't remember where I saw this video...but that statement is etched in my memory. Why do you need a replacement?

[Shane826]

And aren't the torsion bars or the lift system covered by a lifetime warranty?

[Padgett]

If someone added enough weight to the module (bigger AC, solar panels) to exceed the adjustment, they might need a stiffer bar.

[HoMiPa]

Originally Posted by Padgett

If someone added enough weight to the module (bigger AC, solar panels) to exceed the adjustment, they might need a stiffer bar.

And modifications that added weight, might void that warranty...