Trailer construction stuff

I soon learned there were several different types and manufacturers of these trailers, all pretty much based on "how to build" do it yourself articles in 1940's magazines. I've compiled a partial list of teardrop suppliers of complete trailers, parts, and plans. I sent for a back issue of Hot Rod Mechanix (Vol 5 #2 1991) which contains a updated version of the 1947 Mechanix Illustrated plans. I decided on a 4' X 10' version instead of the 8' version, figuring the extra two feet will come in handy. The big difference being the 4 X 8 version is easier to construct using single sheets of common plywood. You can order special, and some large lumber yards may stock 4 X 10 sheets of plywood, but I followed the cheaper method in the magazine article. You make two 4 X 10 sheets of 1/2" plywood from 5 sheets of 1/4" plywood. One sheet is cut into 4 equal 2' X 4' sections. Two full sheets are glued together, staggered by two feet, and the 2 foot sections are added to make 4 X 10 complete sheets for the two sides. They suggest covering the glued sheets with plastic, and shoveling sand on top for weight until the glue dries. I put the previously constructed 2" X 3" wood subframe on top, and piled several Olds and Chevy motors, blocks, and heads on top for a couple days.

I made the frame from 2" square .120 wall mild steel tubing, with a piece of 2" X 3" X 10' .120 wall rectangular for the tongue. The axle is also 2" square material, with spuds I made on a lathe welded into the ends, to mount the left over early Ford carriers I had lying around. I purchased a complete suspension kit (750# springs, shackles, hangers, u-bolts) from a RV place for less than $100, instead of hunting down different items in a junk yard.

I have deviated somewhat from the plans in the magazine, by using the measurements I took from the 1947 trailer pictured at the top. The main difference being the front is more square than teardrop shaped, but allows slightly more room inside. I made a butcher paper pattern, and cut one 4 X 10 plywood side per the pattern, then I layed that sheet on the other and traced it. Next cut that sheet, and when finished, I clamped them together, and used a medium disk in my 9"' body grinder to make them match exactly. Note below I'm cutting out the doors in the sides, while they're lying on the trailer frame itself.

The new and old are quite similar, one big change being the addition of a second door ( one on each side) to make middle of the night exit/entrance as easy as possible. .

I've used 1X2 pine to make a internal framework to contain the 1" styrofoam I purchased at the Home Depot. The styrofoam serves as insulation and the framework also gives support for the oak paneling I'm using to finish the inside.

I purchased four 4 X12 foot sheets of .032" 5052 soft aluminum to cover the plywood. A coat of quick drying sanding sealer was used on all the plywood surfaces to be covered. One sheet is used to cover both side doors, and also the rear hatch. The top requires a complete sheet, and each side will use 10 of the 12 feet.

Weldwoods original formula (red can) contact cement was used on all the skins. They make a adhesive roll for your paint roller handle which really speeds up the application of the contact cement and it also makes it easier to maintain a consistent amount being applied over the large areas. I did the top where the hatch starts down to the very front with one single sheet, a little over 10' in length. I used all the broom handles I could find to lay on the top and keep the aluminum seperated from the roof surface. I formed a "U" on the edge that goes just above the hatch to act as a rain gutter, so I had to start from that edge and work forward, pulling the broom handles out as I moved to the front, using a hard rubber roller to apply pressure to make the contact cement take a good bite.

You can note in the photo below the ripples in the lower right corner, which actually appear more pronounced in the photo, due to the reflection than they really are. I had clamped angle iron along the bottom of the frame to act as a ledge to set the side skin on prior to securing it to the plywood. Now try to imagine a guy carrying a 4 X10' sheet of .032" Jello shaking all over the place. I got it stuck to the lower corner about 3/4" off where it had to go and contact cement I found is VERY un-forgiving. The molding wouldn't hide the screw up, so I had to try and pry it loose, which I eventually did, but not without crinkling the aluminum. The secret was to use the pieces left over from the doors and hatch as shims between the plywood and the skin, resting on the angle iron ledge clamped to the bottom of the frame. Get it set up where it's supposed to be, then pull out the first shim and work your way along the side with the rubber roller. The other side came out perfect using this technique.

Doing one side at a time allows you to enter the trailer and drill holes in the corners where the door opening are. Next, go back outside, and apply duct tape along the outside edge of where you will cut, to keep from scratching the soft aluminum. Insert your sabre/scroll saw blade in one of the holes and cut out the door opening. Trust me, it is much easier to cut the door openings afterwards, then trying to index the two openings together. You use aviation snips to trim up the edges, and smooth with a file.

I purchased a bunch of aluminum "L" molding, which comes pre-drilled, in 16 foot lengths, used on motor homes to go over the edges, and around the windows. TIP- try and find this someplace other than a RV or motorhome shop, and save 30 - 50%. This was all secured with stainless steel 3/4" #6 sheet metal screws and stainless washers. Use a small diameter pilot drill, with a piece of tape around it approximately 3/8 - 1/2" from the tip as a depth gauge. This allows you to pierce the aluminum skin, and keeps the plywood from splitting. A power screwdriver or drill is a must, since I purchased 3 boxes of screws (100 ea) and I only have a small portion of one box left.

I used some repo 39 Ford tail lights in the hatch, and a key and latch mechanism from a Geo Metro hatch back, from a wrecking yard, which releases very easily and there is no handle, just the rubber grommet and key slot which makes for a clean installation. It does generate finger prints on the lid each time you open it.

This is a diagonal view of the "almost ready for the road" trailer.

I haven't finished the ceiling here in these shots, since I need to add the styrofoam, and then apply the paneling. I've put in a battery operated lamp, and tacked some hand towels to 3/8" wooden dowels, hung over the doors on each side with cup hooks. This is just temporary until we get some permanent curtains later. I also picked up a air mattress, which is deflated in these photos, but is thick enough to keep the inside of your legs from rubbing on the edge of the entry way when you get in or out, and is 80" long and 51"wide.

Here are a couple shots of the rear galley area, or at this point just the storage compartment. I was going to install a stainless steel bar sink in the counter top, and make a hook-up and drain just like a motorhome, but we probably won't be doing any actual cooking or living out of this trailer so I haven't bothered at this point. I didn't permanently anchor the counter top down, so I can easily add it later. The counter is from the Home Depot, for a very reasonable $20, and just required cutting a little over an inch from its width. The support is a length of 1/2" rod ten ft long, stuck thru some 1/2" aluminum flat stock, then heated and bent to the proper width, and painted black. It drops automatically by its weight to the top of the counter when the hatch is opened. I also temporarily bolted a 4-plex box in the rear to use for a radio, coffee pot, etc at the campground. No, this wouldn't do you much good out in the woods!

Here is a shot of the almost finished trailer. I replaced the junk wheels with the former front wheels off our 31 Victoria, which I had to change when I added disk brakes. I picked up a set of fenders from one of the local trailer supply stores. They were available in 8, 10 and 12 inch widths, and I selected the 10" set, and made some braces from 1/4" X 2" steel strap, which I welded directly to the inside of the fender. I used all purpose Rust-O-leum spray cans to paint them black and secured them to the trailer with 5/16" bolts.

Here you can see a comparison of the original and the modified copy.