Torsion Axle

[homeroast]

I want to run a couple of things by you before I make a fool of myself to my axle supplier.

My local rubber torsion axle manufacturer's (standens.com (thanks Ken)) lightest duty full axle is rating for 2000#. Assuming my gross trailer weight is 1000#, can I expect half compression to full load?

Also my outside frame is 58" and I want 67" hub to hub. That only leaves 4.5" per side for each torsion arm assembly? Is that enough, do you expect they'll come back and say I need a longer hub to hub distance?

[angib]

Assuming my gross trailer weight is 1000#, can I expect half compression to full load?

I've got mixed info on this. On the one hand, experienced trailer builders talk about light loads (such as you describe) giving little 'settling'.

However the data given by Dexter on their axles is consistently 22.5 degrees from no load to static load (ie, 1g) and only another 10 degrees from static to shock load, which I take to be at least 2g and maybe more than 3g. This indicates a rapidly rising suspension rate - the first 100 pounds of load gets much more suspension movement than the last 100 pounds. So this suggets you'll get a lot more than half compression from half the load.

Also my outside frame is 58" and I want 67" hub to hub. That only leaves 4.5" per side for each torsion arm assembly? Is that enough, do you expect they'll come back and say I need a longer hub to hub distance?

Here's a useful source: Dexter axle measurement pdf. This shows how axle measurments are specified, at least for Dexter's axles. You'll see that the difference between the width over brackets and the hubface is two times the overhang - so you're asking for an overhang of 4.5". Maximum and minimum overhang is specified by most manufacturers, for example:
- A Dexter #9 standard spindle has a minimum overhang of 6.5".
- Dexter say they offer a short #9 spindle with a minimum overhang of 6.0", but I've heard people say it's hard to actually get.
- A Flexiride 2,00lb axle has a minimum overhang of 6.12".

So, sorry, you're going to have to re-think your axle width.

Andrew

[homeroast]

Thanks andrew. Once again you come thru with a plethora of info.

I would like to have more than half compression with 1000#. I didn't think the weight:compression ratio would be a straight line, I just didn't know which way the curve would go, if you know what I mean.

I talked to my axle manufacturer, the minimum offset from frame to hub is the 6.5" you mention. (They make their own axles, but told me they base it off the dexter design.) That leaves me with 3" of clearance between my side wall and the tire, which is more than I was going for, but isn't a deal breaker.

I pick it up next tuesday, hopefully all goes well.

[angib]

the minimum offset from frame to hub is the 6.5" you mention. (They make their own axles, but told me they base it off the dexter design.) That leaves me with 3" of clearance between my side wall and the tire

Beware, that 6.5" offset may leave you with little or no clearance between the sidewall and the trailing arm. Here is a photo that someone* posted of a (I think) minimum overhang Dexter axle:


*(sorry, forgotten who, but a medal is deserved...)

If you are planning to put your sidewalls outside the frame, you may have a problem. Otherwise you should be OK.

Andrew

[homeroast]

I do plan on putting my sides outside the frame, and was aware of the issue when I decided on it. The bottom edge of my sidewalls will be notched to allow the torsion arm to achive shock position. I'll have a piece of wood inside to cover any opening. It will be flush with the floor and hidden from site by my mattress.

[asianflava]

Yes, it's a Dexter axle. 74in face to face and a 58in frame.

[angib]

Yes, it's a Dexter axle. 74in face to face and a 58in frame.

Thanks. So that's an 8" overhang and for a 6.5" overhang, the arm will be 1.5" closer than this to the axle bracket????

Andrew

[asianflava]

Sorry 58in is the bolt hole center for the bracket. The edge of the bracket (frame width) is 60in.

This is how I arrived at my axle width:

frame width 60in
wheel offset 4in X 2
sidewall thickness 1in X 2
sidewall-tire clearance 2in X 2

[homeroast]

Are you using stainless steel hardware to fasten your torsion axles to frame?

[Nitetimes]

Are you using stainless steel hardware to fasten your torsion axles to frame?

Please don't, they aren't designed for that. Use grade 5 or 8 fasteners with a zinc coating.

[Juneaudave]

Are you using stainless steel hardware to fasten your torsion axles to frame?

Please don't, they aren't designed for that. Use grade 5 or 8 fasteners with a zinc coating.

I didn't get any instructions with my Dexter...I assumed I welded the mounting plate to the frame and bolted the axle to the mounting plate. Did I miss something here?

[IndyTom]

HomeRoast,
You should have gotten the proper bolts when you got your axle. I live close enough, I picked mine up at the factory. When I got it, the mounting brackets were already mounted to the axle, and I was told that they were already torqued to the correct tightness. I just set the whole assembly onto the bottom of my frame(upside down of course) and when I had it square to the tongue, I welded in in place.

You might want to go back and see the dealer where you bought your axle.

Tom

[homeroast]

I didn't get a mounting bracket or any hardware with it because I told them I'm top mounting it directly to my angle iron frame. I'll ask them what size bolts and torque is required.

[Jiminsav]

welp, let me throw my two cents worth in here..
I used torsion half shafts from northern tool on my first and ½ trailer, they were 2000 pound axles, meaning each shaft was rated at 1000 pounds load rating.
now, I really over built that puppy, and i'm gonna say it weighed more than 1000 pounds, and yet the axles never settled more then an inch towards the body, and the angle was 45 degrees to start with, and i'd say that the angle might have settled 7 degrees down if that.
so, it is my opinion that torsion axles don't settle as much as people would expect, the rubber just dosn't compress like that.
I think that you'd have to have near the listed weight on the axles for them to move any significant amount.
I've got at least 500 pounds on the current build, and the axles haven't settled a lick yet.

[d-hartman]

Hello I'm new to the group and I live in Cincinnati, Ohio.

I am looking at the Flex ride for its ability to change its start angle.
Does anyone have any complains or concerns about a Dexter or Flex Ride?

Tom,
You mentioned that you picked your axle up at the factory.Where might that be? What brand ?

Thanks !