Electric brake, E-brake options?

[Old#7]

Put the axle dead center on the box, so you can tip it by hand, and rely on whatever you're putting on the nose box to give you your tongue weight.

Or, if you can give me the dimensions of the box, box load, axle location, frame height, and wheel diameter, I think I can calculate how much force we're talking about to tip it up, see if it's realistic.

That's probably what I'll end up doing.

The box will be 4' 6" x 6' with another 2' in front of that for the nose box. Box depth will probably be either 18" or 24" haven't decided yet. Nose box depth will be half of whatever the sides of the main box are. Axle location will (now) be centered on the main box. Tire diameter will be 33". Not sure what you mean about frame height. Is that frame to ground or frame to axle? Box load... I don't think I will ever have more than 1000 lbs evenly distributed in it. Maybe 1500 lbs. max

 

[R_Lefebvre]

Frame height, ground to frame. If you're centering the box on the axle, then I can't do the calculation, as the force will show to be zero. Only the frictional force of the pivot, which I can't do.

As for your intended load, IIRC, a "yard" of gravel is 4000lbs. I found that out *after* I put it in my 1500lbs payload trailer. :Wow1: It's a good trailer and took it with no complaint. Just keep that in mind with your plans.

 

[Old#7]

Lets try this.

Axle 2'6" from the back 3'6" from the front of main box.

Frame height 2' 4"

 

[R_Lefebvre]

Oooh... not good. I did this quick, may have made a mistake, but I think I got it. I'll let you know later if anything hits me.

Assuming a 1000lbs load in the trailer, centered 6" in front of the axle. Assuming the trailer weighs 500lbs, also 6" in front of the axle, which is a bad assumption based on that box... I show you'll need over 800lbs of rearward force to tip it up, not counting friction which will make it worse. At that, you're gonna need at least 0.53 friction coefficient. It'll never work on any slippery surface. Dry pavement, or maybe really firm dry dirt. It won't even work on wet pavement.

The higher up your frame is, the better, or the closer the axle to the centerline, the better.

Good concept, but it doesn't look good on paper.

 

[R_Lefebvre]

I knew I did something wrong.

That would be the case if you chocked the wheels and left the brakes unlocked so the trailer pivoted around the axle.

With the axle locked, and you're pivoting at the contact patch, it's much better. About 350lbs of force. Mu of 0.21. Sounds plausible. It's worth a shot.

 

[Old#7]

So if I do center the axle I would be golden, right? 3' behind axle and 3' in front
+ 2' of nose box (which wouldn't have much weight in it) It should work no problem. That gives me hope! I am sure glad someone is good at math! Better to go off of science than a hunch. Thanks

 

[R_Lefebvre]

Yeah, I would think so. That nose box is a key piece of that puzzle because it adds weight well forward of the axle.

If you center the axle on the box, you'll have to keep that in mind when loading it with dirt, or camping gear, about where you're shifting weight around. When I use my utility trailer for dirt and stuff, it's easy to shift the load more forward or backward until you find a good balance.

The standard trailer construction has the axle back from the box center, makes it all more foolproof. But, it's your call.

 

[Old#7]

When camping or loading the trailer with gear it will be loaded carefully to make sure that heavy stuff goes towards the front and the light stuff goes toward the rear. Hopefully the nose box will be just enough to give me the extra tongue weight I will need as well. The nose box plus the tongue will both give me increased tongue weight. I might even make the tongue out of 1/4" square tube to add more weight. When loading it for utility use, with gravel mulch or whatever, I will need to balance it out good or even mound the load a little to the front when driving. Then when unloading I can push a little of the load towards the back and dump it making the rear half a little heavier and making it easier to dump.

 

[roadkill]

or put a boat style hand winch on the tongue and hook it to the axle. you can then suck up the axle (lift the bed) with the winch. before hydraulics all end dumps were cable operated in this fashion. a winch from the truck pulled the axle towards the truck causing the trailer to lift at it's hinge point.

 

[Old#7]

Not a bad idea. I'll have to look into that. Bottom line, we won't ever know until I actually build this thing. (That might be a while,......anybody want to throw me a small grant?)

 

[indiedog]

Sounds like the problem with the current design is that when backing up the car to tip the load, there may not be enough angle between the tongue and the trailer chassis to push the front of the box up, therefore tipping the load. I think you should keep the wheels just behind centre of the box. The weight of the tongue and tool box will give you your hitch load when it's empty. Keeping the trailer load fairly central should make it all work when travelling but I agree you need to "position" your load.

Now, for when you want to tip a load, under the rear of the pivoting drawbar, could you introduce a drop down leg which you deploy only when you are about to tip a load. It would need to contact the ground (and dig into it or be a locked wheel) and be angling towards the rear of the trailer. (in essence it's a bit like adding another wheel under the rear of the drawbar) When you start your backing up this will "kick" the front of the box sufficiently to allow the drawbar to get some angle on the box.

Hopefully that is somewhat clear. If not I can possibly do a sketch.

EDIT; I suppose the other thing you could do is install a jacking stabilizer at the front of the box to start the lift.

EDIT EDIT; I'm a bit concerned about the stability of the whole thing. Possibly the box could tip quickly and cause problems. Also the lifting drawbar could lift the hitch on the car?

How about a permanently installed standard car jack installed between the drawbar and the front of the box? Remove the locking pin between the two and the jack doesn't let anything get away from you. then wind up the jack to tip the box and load. No moving of cars, less chance of injury from quick moving loads, etc. It's like the poor man's tip truck hydraulic system!

 

[njtaco]

Three things...IMHO, of course.

First, this has been done before, no sense questioning "can it be done." I can't remember when or where, but I've seen it before. It may have been 20 years ago, but I've definitely seen it.

Second, old#7's illustration above, I think the tongue pivot needs to be closer to the axle. That way it is not so "high" when tipping. I believe this may change the tip rate, but it is still a straight backwards force at 24" (or whatever) above the pivot point (the ground.) Feel free to argue that, it is just my opinion. Maybe Rob or someone can run numbers on that idea.

Third, the tongue box should be just that...not attached to the main box when tipping. No sense lifting 50-100 lbs 6 feet up in the air when 4 will do. That way it is dedicated tongue weight, and does not affect the axle position relative to the rear box so much.

My 2c, worth what you paid...

Bob

 

[njtaco]

I'm a bit concerned about the stability of the whole thing. Possibly the box could tip quickly and cause problems.

I agree...

Maybe a simple shock absorber would slow the process down, and keep with the K.I.S.S. theme?

 

[I Leak Oil]

Three things...IMHO, of course.

First, this has been done before, no sense questioning "can it be done." I can't remember when or where, but I've seen it before. It may have been 20 years ago, but I've definitely seen it.

I guess this really boils it down for me. Of course it can be done. The fact that it hasn't become popular and is not put into practice often is probably a good indicator that it is difficult to make work and can be uncontrollably dangerous. Sounds good in theory but in real world conditions it probably is more hassle than it's worth.
By the time you add bottle jacks, hand winches or shock absorbers your not far from just making it a simple and safe hinge and piston set up.
Jason T.

 

[ntsqd]

The way that I've seen it done is to use a Harbor Freight or Northern Tool engine hoist (aka "cherry picker") hydraulic ram to do the tilting.
Complicates the tongue a little, but I think that it has fewer compromises.