Cargo Trailer Build

[Tony01]

I'm building a large cargo trailer. I built the frame yesterday evening, today I finished the dropouts and will be welding them on tomorrow. I still have to figure where to put the crossmembers and how to make a box.

The wheels are 26" for now but I'd like to go with 20" someday. Just seems like a better idea and the trailer'd be lower with stronger wheels. I just don't have tires or tubes in 20" anyway.

The inside distance between the box tubes for the wheel mounts is only 3.7". even though fronts have an OLD of 4", the box tubes have a radius which will make welding dropouts difficult, so I figured the 1.5" box has around .180"R and the other one has about .125"R so the dropouts should sit flat and the welds will be nice n strong. Front wheel hubs themselves aren't actually 4" wide so there is no problem, and the trailer can obviously handle 3" wide tires!

I'm thinking of using the big 4x4 box tubing, cutting it lengthwise in 4 places to make 2x2" angle iron and using that are the box corners, then bolting plywood in for the sides. Might be kinda heavy though. The frame already weighs a lot, maybe 25lbs without any other stuff on it...

The overall length is 4ft, don't remember the width.

Cargo trailer frame by Tony K, on Flickr

trailer mocked by Tony K, on Flickr

trailer still mocked by Tony K, on Flickr

 

[racie35]

It's getting heavy...4x4 tubing you wanna use now?
How big a box made of what? Then there's the load you carry....just wondering

 

[scratchbuilder]

I made this one to carry 6' fencing on and bikes. It connects to seat post with air hose connector.

 

[Tony01]

It's getting heavy...4x4 tubing you wanna use now?
How big a box made of what? Then there's the load you carry....just wondering

The inner rectangle is 18x48 and that will be the box footprint I guess. Maybe 10" tall. I guess I don't have to use full lengths of box tubing. Just 3" tall corners to bolt the plywood to. The ply I have is 9/16". The overall trailer width is 31", so that I can tow it through the side gate.

Load will hopefully be up to 200lbs. I have a line on free engines attached to various equipment like Briggs 5hp water pumps and generators, some seized, and I'd prefer to make the least amount of trips.

I hope these 26" wheels can handle the side loads until I get some cheapo steel wheel master 20" wheels for $21 a piece.

 

[Tony01]

I made this one to carry 6' fencing on and bikes. It connects to seat post with air hose connector.

Whoa that's a big one. Air hose connector is a good idea. I'm gonna try a hitch using two 3" caster wheels. Hasnt cost me a dime yet. How much weight can it handle? And what is the top speed ya run it at? How's it handle?

 

[scratchbuilder]

Weight, I can only guess 300 distributed. The last I used it 15, 20 mph. It's my bike table now. Keeping it low was my goal. Air hose w/ a 3/4 socket swivel. Forgot to mention the swivel.

 

[Tony01]

300, nice. I just hope my bike can pull that!!

Some more progress. Gonna be towing it tomorrow.



I did the alignment by clamping tubing against the inner rails and pushing the truer of the two wheels against the tubing. The rails are out of parallel about 1/32" with the smaller dimension at the front. So if I screwed up, then there is a higher probability that I'll have toe-in or zero toe rather than toe-out.

Wheels are 26" for now.

Untitled by Tony K, on Flickr

Untitled by Tony K, on Flickr

I'll be using dual caster wheels as the swivel and hitch. Made a hitch arm with two caster mount positions. When I switch to 20" wheels I can move the caster to the upper position to keep the trailer level. I'll add in a couple of gussets on that box tube.

Untitled by Tony K, on Flickr

Untitled by Tony K, on Flickr

Welded in the dropouts. Some of my best welds and of course nobody will ever see them.

Also put corner brackets with little holes to screw in the plywood.

Untitled by Tony K, on Flickr

still need to cut and fit the plywood, mount the hitch to the bike, find enough 5/16" bolts... lol.. I need 8 of em yea right.. and make a few gussets and weld em in. and paint. argh so much to do.

 

[Tony01]

Well last month I did all this work and the trailer has been sitting. It's up for sale but nobody seems to want it.

The caster wheel hitch didn't work. I wasn't thinking again! caster wheels and their bearings are for working in compression.. NOT TENSION. Ball bearings all fell out before I made it 100 ft. Though it did seem to work great for the first 10 ft..

Ended up using a female heim joint mounted to my rear triangle gusset. I decided to double up the left side gusset to strengthen the area for pulling a trailer. I used the 3/8" size with a ring ended pin with the spring loaded ball bearing on the other side for an easy hitch pin that only takes one second to put in or take out. Made a branch off my taillight hot wire to allow the trailer taillight to plug in near the joint. Ground is still frame of bike/frame of trailer with the hitch making the floating ground. Works great!

IMG_2855 by Tony K



The trailer arm is 1" steel tubing, it's sleeved at the one joint for strength (I had an arm failure out on the road with a fully loaded trailer.. got it home after making a splint for it from duct tape and wrenches.. barely). The trailer end is welded and braced all over to make sure it don't break. The hitch end is 1.25" box tubing that was cut into triangle tongues at the end and welded lengthwise to the tubing. The edge of the box tube has two 5/16" nuts on the inside, welded, to make sure it doesn't rattle up and down on the helm joint, and drilled right through both and box for 3/8" for the hitch pin. Pin goes in very snug and locks when the ball bearing pops out.

IMG_2857 by Tony K, on Flickr

After some major load pulling, the ball end of the heim joint has bent downward significantly. I won't be pulling SUCH heavy loads any more so hopefully it won't ever break, but I see now I should have gone with half inch.

Went to my buddy's house and he helped me install pegboard and wood to make the box section of the trailer.

IMG_2868 by Tony K, on Flickr

I had made corner pieces from that same box tube (also my transmission housing, headlight bracket, motor mount.. love the stuff). Put holes in to easy screw down wood, and the job went fast with my buddy.

Painted the underside with undercoat, the bed with bedliner, and the rest with black primer and grey paint as needed.

IMG_2897 by Tony K, on Flickr

Trailer was used to haul a few loads between 150-250 lbs. Felt REALLY weird at the handlebars fully loaded, unloaded almost like it wasn't there.

IMG_2871 by Tony K, on Flickr

I may add a small hub-a-like fixture to the middle crossbar to tow other bikes.