modifiying trailer for dump action?

[Oldmax]

This is an ongoing project of mine.

 

[Oldmax]

This is an ongoing project of mine. If intersted I can send measurments of mine.

 

[ultrarunner]

I built one about 20 years ago using a "Camper Jack" to raise the trailer... It's work find ever since... the only shortcoming is it is pump action and not that quick.

The trailer is home-made...even the hitch and the swing boom... I used to have lots of time and little money... now it's no time with a little more money.

The Jack is mounted on the trailer draw-bar and the trailer pivots on the axle... one of the beauties of having a single axle trailer.

I also have a tilt bed car hauler that works the same way without the jack.

On the plus side... the dumping mechanism and installing it cost less that $100 plus my time...

I'll try to take a picture.

 

[bostonbear]

I work at camp robinson in arkansas. we, the guys at work, had the same idea when they post on auction. we talk ag morning at break. before i was full time i worked at a plastic plant. the Mech Eng's always had to do all kinds of math. i am an electrical Eng. i found just going to a pneudralic or motion indstrual supply the inside sales guys wil be able to help you. yes you'll need to make a frame for you trailer.

 

[Skyco]

Whatever you decide, remember that horizontal placement of the cylinder requires a big cylinder and beefy hinges, and gives only a limited lift force where it is needed most: when the bed is horizontal. Then when it tips up, the cylinder gets more effective when the dirt is already starting to roll out, which means you loose a lot of speed to pump oil into that big cylinder.

The more vertical you place it, the more efficient the overall design, both mechanically and hydraulic.

Here is my dilemna- my scissor lift trailer will dump its 5 ton load normally with little trouble. However a few times the loader operator has dropped the load piled a little toward the front, or I'm nose down on a hill where I want to dump. The sizing of the cylinder and pump is right on the hairy (cheaped out?) edge of lifting when everything is perfect. So when front heavy it can't get the bed to rise without a little help, I usually use a Hi-Lift jack on a corner to get it going. Once its up 2 or 3 inches it takes off and goes fine.

My thought is if I cut the trailer end cylinder mount hinge off and reweld/remake it a few inches lower it should give it more off the line lift at the expense of a couple of degrees of ultimate dump angle.

Any mechanical engineers out there that can confirm my plan?

Can't use a bigger cylinder because there isn't room. I have considered installing a small "booster" cylinder vertically at the front of the dump bed to push that extra few inches to get it going. Cost is a minor issue here and all the extra plumbing into the hydraulic pump.

Below is a pic of a trailer like mine- the large "hinge" circled at the lower front is what I'm proposing to lower.

 

[Renze]

Skyco,

given the geometry of your scissor lift, placing it lower so it doesnt reach as much of a dead end when lowered, would certainly make it easier for your hydraulic pump to punch out the bed from a dead start.

Just use a tape measure to measure the total expansion of the scissor lift, deduct the inches you want to lower the attachment hinge, then lower the bed to that length, to see if you can live with the dump angle, before deciding to cut up a perfectly good dumptrailer...

 

[hr3]

Skyco,, How many pounds of life do you think your appling with the high lift jack??? The reason I ask is a few years back I built a show truck with a air powered lift like yours.. but after putting the finishing touches on the truck it wouldn't lift the finished bed,,, I put a come along on my dear scales and lifted it untill the bed would move on it's own,,, about 200lbs is what it took..

The truck was done,,,frame was all clear coated and I couldn't move my pivot point with out a lot of redoing,,,Sooo to make a long story short I installed a set of struts to help with the first inch or so,,,Struts might not work for you but maybe some short springs near the front between the frames...

Just a thought,,,

 

[jmc]

My thought is if I cut the trailer end cylinder mount hinge off and reweld/remake it a few inches lower it should give it more off the line lift at the expense of a couple of degrees of ultimate dump angle.

Any mechanical engineers out there that can confirm my plan?

Skyco,

You can confirm it yourself by making a 2D scale model of each component's profile out of index card stock. Mark your pivot points with a dot then assemble the linkage by pinning all the attachment points together with common pins. A working scale model of the cylinder, since it telescopes as well, will take a little more work on your part. You can then articulate the linkage and adjust attachment points, etc.

John

 

[wushaw]

Me and a buddy of mine had to up size the lifting mechanism in our 14k dump trailer, it was a undersized straight cylinder, we put a 18k Colt scissor lift in it. Lifting problem solved.

You can up size the whole scissor mechanism, It may cost a lot more than you may want to spend but it will lift anything you put into it.