Help with a DIY motorized trailer dolly

[LEVE]

How about just buying a used riding lawn tractor? They can be found for a reasonable price on CL. The only drawback I can think of is that you'll have to have room store it. I use mine as a tug around the garage to tow non-working vehicles into place. I've seen them used to pull trailers around, even up small inclines.

[IndyGarage]

I built a trailer mover out of a hand truck, a 2000lb worm gear winch, a chain drive and a hitch mount. I saw commercial models that go for $1500, but I thought they looked like overkill for what I wanted.

I got a hand truck with a solid axle, and welded one of the wheels solid to the axle - put a chain drive from a 2000lb worm winch to the axle, and welded on a hitch mount so I could interchange a tow bar for different ball sizes.

I also put a third castering wheel with a locking mechanism on the back of the hitch mount so that when you lean it back it sits on three wheels and the hitch mount is horizontal.

I wanted to move my boat trailer and my 6x12 box trailer around without hitching it to the truck. The box trailer fits into my garage with about 1 inch on both sides and on top to spare, and it's very difficult to fit it in there with a truck. Good news is this thing makes that job a lot easier.

I drive the winch with my Milwaukee V28 drill. I wanted to do this, because I didn't want a cord or another 12volt car battery sitting around to maintain. The drill has plenty of power because the winch is 15:1 reducition, and I further reduce it, 3:1 with the chain, so if I run my drill in low range at 400 RPM that means the wheels turn at less than 10 rpm - at about 1 foot diameter for the wheels, the maximum moving speed is about 30 feet per minute.

OK, so here are the things I learned:

1. That Harbour Freight 2000 pound worm winch you were thinking of using is total junk. First the bearings were so loose, that the gears would slip. Then when I fixed that, and got everything installed, I found out the gears aren't hardened, and they grind each other to dust under load. I bought a Thern lubed gear winch that I'm going to replace it with off Ebay, but it seems almost too nice to cut up an use in this application.

2. The geartrain works like a charm - the drill has plenty of power and can move my trailers all over the driveway - On flat ground - I found out the unit simply doesn't have enough weight to get traction to pull the trailers up any kind of grade at all - this was a disappointment. I was hoping to move my trailer down a slight grade that I can't back my truck down - no way.

3. I built an extension out of a 1/2 inch steel rod to route power to the winch, mounted on the base of the hand truck, from near the handle. I just chuck the drill onto the rod (I ground a triangle on the end of the rod) and I can run the drill with one hand easily while guiding it with the other hand. At 400 RPM, every little defect in my driveshaft shows up, and vibrates the whole thing.

4. Originally I planned on welding only 1 wheel on the hand truck solid to the axle, so I could have the other to freewheel so I could turn it. It turns out that the torque to that single wheel was a lot, and I couldn't hold it straight - I ended up welding both wheels solid, which fixes the torque steer issue, but now steering it at all is a lot of work.

5. The hand truck idea was a good one, because it inherently has plenty of strength for the tongue weight, and I wanted it to be able to stand up vertically without taking up much storage room However there are a couple of problems. First I wanted to be able to pick up the trailer by laying the hand truck back, thus raising the ball into the hitch. There is a bit of a geometry trick, in that you want the ball center placed so the center of gravity is behind the main wheels. This means the truck needs to lay back at least at a 45 degree angle.

The second problem is that even with the truck laying back at about a 45 degree angle, the frame of it still interferes with the hitch triangle when you try to turn sharply - shallow turns are fine, but you really want to beable to turn 90 degrees or even more.


Ideally you would design it with a flat truck bed type base with the handle and drive switches sticking out well behind the location of the hitch.

If I were doing it over again - I would: 1. use a much higher quality winch from the start. 2. design the base differently for easier turning (I'll probably modify mine somewhat - but I don't want to lose the simplicity of the drill motor powering it - that works really well. I even tried moving the trailers with my Milwaukee M12 driver, and it moved my 1200lb boat trailer fine.

In the end, I'm not sure I will bother to do much more than fix this one because I had hoped to be able to pull the trailers up the hill in my driveway with it, and that simply isn't going to happen. It does work great for pulling the box trailer in and out of the garage, and it would work great for pulling an airplane in and out of a hangar.

More recently, I saw and copied a trailer mover for a forklift. I made one fo those also, and it works like gangbusters - problem is, I don't have a forklift at home, and even so I couldn't use it to move anything up any kind of grade. One of those Mini skid steers would be the ideal trailer mover.

[mike54]

Originally Posted by IndyGarage

I built a trailer mover out of a hand truck, a 2000lb worm gear winch, a chain drive and a hitch mount. I saw commercial models that go for $1500, but I thought they looked like overkill for what I wanted.

. . . . . snip lots of really good info . . . . . .

Thanks. Nothing like first hand experience. I'm still doing research but I don't think the winch is the way to go anymore. They aren't rated for continious use. Those Razor electric motorcycles have a 500W motor in them that could be useful. If I could pick one up used that might be the way to go. I'd get a battery pack and a controller that way too. I don't have a drill motor that I could use so that's not really an option.
Thanks again.

[srmofo]

Im just going to throw this out there, but what about an old starter.

A few years ago my clutch on my plow truck (loaded) somehow blew apart and became permanently engaged. I couldnt shift gears after it was started but it would start and run fine in neutral. I was only a few miles from the shop so I figured I could make it there. I simply put it in second, pushed the clutch pedal in to close the circuit on the safety switch, and started it. Once I was moving fast enough to avoid stalling it (only a second or 3) I let the starter off and rolled at a moderate speed around 20mph. I timed the lights best I could and only had to restart it once.

Point of the story is that a starter has enough juice to push a little trailer. Probably too much unless you find one from a tiny four banger. All you would need is the flywheel that matches the starter, some pillow blocks to support the axle assembly thats welded to the axles/wheels, and some scrap steel to build the frame. Use a ford starter relay and a push button switch.

Only issues I could see are the instant on/instant off might be hard to control and it would most likely have too much power unless geared down....or had much smaller wheels than original equiped on the donor car

[creativecars]

And I was wondering what to do with the power wheel chair that I bought off ebay. I have a power chair chassis that has 2-36V electric motors and several power actuators. The motors are very powerful, well enough to haul a 3-400 lb person around for a couple hours. It has 12" tall pneumatic tires on the back and 6" swivels on the front. Over all the chassis minus the seat, handles and foot braces is about 16" tall and 2' square. Something like this may work?

[IndyGarage]

The problem is not the power in the motor - that's easy, because you can gear it down enough that almost any motor could power it.

Like I said, my little 12V Milwaukee cordless moved my trailers fine. It would probably run the batteries on it down pretty quick. My v28 milwaukee would move them all over the neighborhood, so a starter motor could do it, a wheelchair motor, anything - but then you've got to carry and maintain the batteries - that's why I use a cordless drill. I can just walk over to the mover, chuck the drill on it and go.

The problem is having a power source that isn't a PIA to maintain.

[weegaz22]

sounds like a good excuse to buy a cheap quadbike, not to mention the ability to have some fun on it

[UP Cat]

So I spent most of last year coming up with my own home built trailer mover. We have a large snowmobile trailer that we sometime put up to 5 or 6 snowmobiles on. I have a welder but wanted to see if I could build a mover without having to weld anything. I came up with something that works pretty well. I am going to load video showing it's use but have a question for you all since you may be able to provide input. In order to cover my "R&D" costs I was going to try to sell copies of my plans with step by step instructions for assembly. If reasonably priced (15-20 bucks), is it feasible to think that someone would pay for a set of instructions? The total amount for the parts that I used was about 400$ but compared to the ones you can buy online it was about half of their cheapest model. I have yet to load the mover past it's capacity and it will even pivot the trailer (double axle) on a concrete floor. This is a tough chore as the front set of tires basically drag and provide a significant amount of resistance. Thoughts on this from anyone?

[atpalmer]

Originally Posted by UP Cat

So I spent most of last year coming up with my own home built trailer mover. We have a large snowmobile trailer that we sometime put up to 5 or 6 snowmobiles on. I have a welder but wanted to see if I could build a mover without having to weld anything. I came up with something that works pretty well. I am going to load video showing it's use but have a question for you all since you may be able to provide input. In order to cover my "R&D" costs I was going to try to sell copies of my plans with step by step instructions for assembly. If reasonably priced (15-20 bucks), is it feasible to think that someone would pay for a set of instructions? The total amount for the parts that I used was about 400$ but compared to the ones you can buy online it was about half of their cheapest model. I have yet to load the mover past it's capacity and it will even pivot the trailer (double axle) on a concrete floor. This is a tough chore as the front set of tires basically drag and provide a significant amount of resistance. Thoughts on this from anyone?

No interests in paying for plans, tell us how you did it for free.

[UP Cat]

Hard work, trial and error, and a lot of trips to the hardware store.

Thanks...

I'm not trying to make a fortune. Just trying to cover my original costs to figure it out.

[fergus]

Maybe you should go register as a vendor Up Cat... this forum is about people showing off their projects and or helping each other. Not charging for a peek at what they did.

[Regnar]

I would and have paid for plans in the past. They are a real time saver "IF" they are complete. What I am talking about is a complete list of materials with vendors and cost at the time of build. Good photos and accurate CAD models. I wont lie I have asked for my money back 2 times because the plans that were given was horrible or materials unattanable. I would also say be ready to reply to a lot of questions. My friend sold plans and gave up because people would email him stupid questions all day long. He could never figure out why people couldnt just use what was in the plans the way he showed them how.

[Charles (in GA)]

Originally Posted by kmacht

If the trailer won't be loaded and is fairly light there are other options besides a winch motor. I have seen people make motorized tow bars for airplanes using a cordless drill.

Keith

Neighbor did this very thing with an old aluminum bodied corded Craftsman drill, it worked great to move a heavy twin engine aircraft. I can imagine a good cordless drill would work nicely with gear reduction from sprockets or pulleys.

Charles

[Strouty]

Originally Posted by srmofo

Im just going to throw this out there, but what about an old starter.

This was my first thought, we used to make winches out of starters and flywheels to load cars. As long as you have a starter from an older V8, it should hold up. Another thing everyone has stated is trouble turning. I would make it like a skid steer so you could have two tires on each side and control them separately that would be easier to turn and as long as your grass wasn't all wet it should tear it all to hell.

[UP Cat]

If it was just a peek I would agree. I have created a full 3D model in sketchup and was considering creating a CAD set of blue prints. I have the full materials list along with websites to get them from. I wasn't looking to use this site as a method of sale (I would use ebay). I was looking for feedback to see if it's something people would pay for. If there was something available when I started I personally would have paid 20 bucks easily as I'm sure I spent an extra couple hundred dollars with trial and error.

[UP Cat]

Originally Posted by Regnar

I would and have paid for plans in the past. They are a real time saver "IF" they are complete. What I am talking about is a complete list of materials with vendors and cost at the time of build. Good photos and accurate CAD models. I wont lie I have asked for my money back 2 times because the plans that were given was horrible or materials unattanable. I would also say be ready to reply to a lot of questions. My friend sold plans and gave up because people would email him stupid questions all day long. He could never figure out why people couldnt just use what was in the plans the way he showed them how.

Thanks for the feedback. I guess it would get pretty out of hand with questions. Something I will have to take into consideration.

[metal1313]

what about a commercial mower? they are plenty strong, and can push a decent amount of weight, so buying a used one and removing the deck you could prop use it as is.

actually you may be able to use it as is, and then to mow the lawn. solves the storage issue and saves time