Snoozy axles

[Mike Magee]

I guess Snoozy started out with a wider axle, thus the 7'11" notation in the specs. They must have gotten Wesco to switch to a narrower axle at some point. But for some reason, I ended up with a wider one. Sure wish I hadn't. Maybe I would not have hit that rock.

[Flharleycop]

Originally Posted by carlkeigley

No gap on the Snoozy Keith

http://www.fiberglassrv.com/forums/a...chmentid=64551

WOW big difference Carl, thanks for the pic.

[Brian B-P]

Originally Posted by Mike Magee

I guess Snoozy started out with a wider axle, thus the 7'11" notation in the specs. They must have gotten Wesco to switch to a narrower axle at some point.

But it looks like 7'11" is for the narrower axle: Mike, measure your Lil Hauly across the fenders and I think you will find it is more like 102" wide.

[Brian B-P]

Originally Posted by carlkeigley

No gap on the Snoozy Keith

http://www.fiberglassrv.com/forums/a...chmentid=64551

Thanks Carl, that clearly shows the difference in clearance between your trailer and Mike's (shown in http://www.fiberglassrv.com/forums/a...6&d=1379462284).

These photos also clearly show the substantial taper to the body which allows the suspension arms to have lots of clearance - regardless of their angle - even with the fenders snug up to the body. I see no reason to ever equip one of these trailers with fenders any further out than against the body, unless accommodating substantially wider tires... and Mike's axle is too wide for much wider tires, because they would put him over the legal width limit.

[Brian B-P]

Originally Posted by Mike Magee

I believe he said it would be about 6" behind where the axle currently attaches, and most likely they will be able to leave the current attachment plates intact (so a reversal would be easy should the occasion ever arise).

Did he mean that the new beam axle will be about 6" behind where the independent axle tube attaches? Since the hubs are behind the cross-tube of the independent suspension (by 6" in a typical Torflex #10), this may mean that the hubs will be in the original location. This would make sense to me: trailer leaf springs are typically a couple of feet long, so the front spring mounts would be just ahead of the original brackets, and the rear spring mounts would be well behind. Unless you add shocks (which I would, and did) or bump stops, there is no attachment to the frame in the vicinity of the axle beam in a leaf setup.

If the hubs/wheels are actually moving back by 6", then the fenders would need to move as well. How are those fender supports attached to the frame?

Originally Posted by Mike Magee

This will contribute a small amount of additional tongue weight. I weighed the tongue fully loaded in the latter part of August, and it was 330 lbs. So that may go up to 350 or 360, perhaps?

If the axle location really does move, the change can be calculated. If (for instance) the 330 pounds was 11% of the total trailer weight (which would then be 3000 pounds), then the balance point is forward of the axle by 11% of the distance from axle to coupler. Move the axle back, calculate what percentage the distance from the same balance point to the new axle location is of the new axle-to-coupler distance, and that's your new tongue weight percentage.

In rough terms, the balance point is likely about a foot forward of the axle. Move the axle back 6" and you're increasing that by 50% while only stretching the coupler-to-axle distance by about 5%... so your tongue weight will go up massively. I'm talking about an increase from 330 pounds to close to 500 pounds. Moving the axle 6" is a big deal.

[Mike Magee]

Got the trailer back today. I got slammed with work, so no time for pictures or anything. The wheels are in the same position as before, right under the fenders (which they lowered). But since the axle beam is probably at the midpoint of the springs and is directly at the point of the fenders, and since the torsion axle was forward of that and the arms extended rearward to the wheels under the fenders, I was figuring that the support point would be changed. Am I correct? The trailer guy seemed to think the support point was at the tires, not at the axle, and I didn't argue the point. I'll have to weigh the tongue sometime and see how heavy it is.

[Brian B-P]

Originally Posted by Mike Magee

I was figuring that the support point would be changed. Am I correct? The trailer guy seemed to think the support point was at the tires, not at the axle I'll have to weigh the tongue sometime and see how heavy it is.

The trailer guy is correct, the position of independent suspension's square tube has nothing to do with the balance of the trailer. The support is still at the wheel location, whether the arms are short or long. The internal structure or mechanism within the trailer doesn't change the fact that the forces supporting it are at the wheels and the coupler.

Originally Posted by Mike Magee

I'll have to weigh the tongue sometime and see how heavy it is.

Good idea. They kept the wheels in the same place, so the balance is the same, other than the minor effect of the weight of the new axle/suspension itself being further back. With the steel of the axle centred at the wheels instead of ahead of them, the tongue weight should be very slightly reduced.

[Mike Magee]

I don't get it, Brian. Here is how I visualize the situation. Imagine that you have a 1' long piece of board and you can balance it on your index finger. You may balance it on your finger with your arm vertical, or with your arm at a 45 degree angle, or even at a 75 degree angle. But the board is still balanced at the point where the tip of your finger touches it, and not whether your elbow is directly below or not. But if you move your finger back an inch on the board, your board will tip. Ok, now imagine that the tip of your finger is the axle tube, and your elbow is the wheel. If you move the axle tube (finger) but leave the wheel (elbow) the same place, I would think that you have changed how the trailer is balanced on the axle. What am I missing?

[Brian B-P]

Originally Posted by Mike Magee

Here is how I visualize the situation. Imagine that you have a 1' long piece of board and you can balance it on your index finger. You may balance it on your finger with your arm vertical, or with your arm at a 45 degree angle, or even at a 75 degree angle. But the board is still balanced at the point where the tip of your finger touches it, and not whether your elbow is directly below or not. But if you move your finger back an inch on the board, your board will tip.

Okay... your finger is the centre of the wheel and tire (or the spindle of the axle)... not the square tube of the independent suspension.

Originally Posted by Mike Magee

Ok, now imagine that the tip of your finger is the axle tube, and your elbow is the wheel. If you move the axle tube (finger) but leave the wheel (elbow) the same place, I would think that you have changed how the trailer is balanced on the axle.

Instead of your finger, try your whole hand (the board needs to be small enough to grip the board like a handle). To hold the board in the middle, you don't have to twist it, just hold it up. You can move where you grip the board off of centre, but you have to twist with your wrist to keep the long end from dropping. If you're resting that elbow on a table (like the wheel rests on the ground) the whole mess is still balanced... you only have to twist with your wrist, not your arm.

The independent suspension arm doesn't just push up on the tube that it pivots in, it also applies lots of torque to the tube. If the bracket was long enough to reach all the way past the wheel centre line, you could balance the trailer on that bracket just as if you were setting the trailer frame directly on your new straight beam axle (without the leaf springs). All the bits between the wheel and frame don't matter to the balance.

[Byron Kinnaman]

I believe Brian to be correct in that the balance has to do with wheel location. If you put an arm all the way to the rear of trailer and wheels in same place the balance wouldn't change. The mass of the trailer pivots at the wheel axle.

[Thomas G.]

Brian is right. The balance point is determined by a combination of direct vertical forces and moments (torsion). The torsion element is harder to visualize, but think of a WDH which it pushes down on the TV's front wheels (and trailer axle) via a large moment induced at the coupler interface.

Back in engineering school we used a free body diagram to understand such things, but I'm too lazy to generate one here.

A fun example:

[Mike Magee]

I hadn't considered the twisting action in the forces being applied. Now I get it.

[Mike Magee]

After some pondering, I decided to ask Alan at Snoozy for reimbursement of my axle replacement cost. We'll see what he has to say.

As near as I can figure, my wheels and fenders exceeded the 102" maximum width allowed by law in nearly every state, not to mention being well over the 96" allowed in a few states. While I cannot blame the company for a road hazard, the fact is that I do not believe I would have ever struck that rock just off the edge of the pavement (my wheel would not have been off the pavement) were it not for the excessive axle width.

Why my trailer was fitted with such an ungodly-wide axle, when it was obviously not necessary, is beyond me.

I didn't ask for the cost of the new wheel rim or tires, or for lost income from downtime caused, but only for the axle replacement and moving of fenders.

[Mike Magee]

Update: Alan said that he would be willing to send me $250, and made some points that he felt were in his favor. He also cautioned me that, according to Wesco, the frame should be reinforced (details not given) if used with a spring axle. I responded to those points, but said that the $250 would be acceptable if he would include instructions on where/how the frame should be reinforced. Or in the alternative, I'd be ok with another torsion axle sent at no charge.

To which he wrote simply, "Your demands are unreasonable and unacceptable."

[Mike Magee]

No further response from Alan to any of my emails. I told him to forget about the money, but to please never again sell a 8.5' wide axle without express permission of the purchaser.

It's important to note that my experience was with the cargo version, not the camping version.

That said, I would advise anyone buying a trailer from Smoakin Concepts to diligently inspect the unit at pickup. Because it seems like they are willing to change things from advertised specs without notification. If they will deviate from the advertised 7'11" width, what's next? Will the bed suddenly be made only 54" wide instead of 60"? Will the shell be made of molded plastic instead of FG, with no notice to the buyer? I do not understand the "let's just make one this way instead, and say nothing to the buyer" strategy. I would not ever have accepted the trailer if I'd known about the width. And yes, dummy me, I should have had a tape measure with me and measured it instead of assuming that I knew what I was getting.

The rationale presented by Alan for the wider axle was, it was for greater stability in use with cargo. I don't get that, either. If one looks at the cargo trailers for sale nowadays, whether 4', 5', or 6' wide boxes, they all put the wheels just far enough from the body to clear it. 7' wide cargo trailers even have the wheels tucked under the body. If Haulmark, Cargo Craft, and all the other mfrs don't see the need to 'increase stability' with a super wide axle, why the Hauley? It seems like a rookie error. But then, Alan was previously a boat builder by trade, so what can be expected?

Beyond the axle, I'm happy with the way it tows. It's easier on my drive train, for sure.

[carlkeigley]

That's the sad thing, most of us are newbies to the camper world.

[Ken C]

Thanks for taking the time to type out your experience and share it with everyone.