azgreg noob questions

[azgreg]

I thought I'd post a thread to help in my planning for my build that will start this fall. The plan is for a 5'x8' (profile undecided). I'm building the trailer. It won't be my first, I built a car hauler years ago during my stock car racing days. I'm planning on using one of the axles (3500 lb.) and one set of leafs. I plan to make it out of 2"x2"X.125 square" tubing with either square cross braces or 2"x2" angle. I'm not sure of the tongue bar. Is 2"x2" sufficient of maybe 2"x3"?

I will have more (many more) questions and plan on using this thread until the build starts. I can't wait.

[noseoil]

2 X 2 X 1/8" should be fine, just remember the trailer will act like a structural member of the frame once it's fastened in place. The box you build will help stiffen the frame. Some people have built by just using the box as the frame and fastening the axle & hitch to it with plates & bolts. I would not drill into the frame members themselves for mounting things, use angles or tabs welded in place to put the bolts through. That having been said, make sure the A-frame is fastened well back towards the axle and made plenty stiff to resist the twisting & bending loads it will meet on the roads. This is one place you will want to beef things up and make stronger than your regular frame tubing.

[azgreg]

I did a quick mock up of the frame in Solid Works. It's 5' x 8' 2"x2"x.125" square tube with 2"x2"x.1875" square for the tongue (4' long). The piece in the back is a receiver for a bike rack.

[KCStudly]

Looks okay to me, but the long extensions behind the sides of the 'A' shouldn't be necessary for strength. Perhaps you extended them for another reason?

[azgreg]

I've always seen them on production trailers. I assumed that it tied the "A" part of the tongue into the front leaf hanger.

[skinnedknuckles]

That mock up looks almost identical to my teardrop frame. I did use 2x3 for the main tongue and 2x2 for the angle braces. I built many small trailers used in hauling construction equipment , and I always bring the angled frame members back to the front spring hanger. I know that the actual camper "box" will add stiffness to the whole unit but I have dealt with far too many trailers that have bent right where the angled frame members end if not ending at the front spring hanger. I figure that it doesn't add too much weight and it gives me piece of mind and its probably just a habit to do it that way I should have probably thought out the weight thing alittle more as I was building things. These campers weigh so little that what I have practiced in the past does not really come into play, its not like we are building a 2000+ pound trailer to haul a 3500+ pound vehicle. That being said, I still like what you came up with for a mock up Just be careful on axle width and you may want to change something about the spring so it will not be too high a spring rate.
Have fun,
Paul

[azgreg]

Floor and roof questions. I'm trying to decide how I want to build my floor. I'm either going to build the floor to the dimensions of the trailer or build it with wood over the side to give more meat to screw the walls to. Also, is it better to install the roof where the edges of the roof are exposed or where the edges of the walls are exposed. Currently I plan on sealing the exterior and painting it instead of aluminum or staining. Both of these will go a long way in determining how wide I build the trailer.

[KCStudly]

Start at the top and decide what size sheet stock you want to use. If your trailer is 60 inches wide and you build the walls to cover the side of the trailer frame, then expect the roof panel to overlap the walls, you might fall short or end up using a bunch more sheets to get the length needed to get across.

Using the Fredrick's method (or a variation of it) where the ceiling panel sits down on a ledge or rabbet built into the top of the wall gives you the advantage of being able to prefinish and assemble from the inside out.

Whether the roof panel sits inside the wall or over it really depends on how you intend to trim or seal the corner edges, but it is far easier to let the top run wild off the edge and trim flush after installation than it is to get it to fit right the first time, especially if you have a curved roof and have to bend the skin; it will want to "walk" some one way or the other. Better to leave it wide, let it walk a little, and trim flush after.

[azgreg]

OK, I think I've settled on a wall mounting method. The floor will be offset 1" from the edge of the frame and the wall will sit on the frame with the outer skin going down to the bottom of the frame. The floor will be 1"x3" framing and 3/4" insulation sandwiched by 1/4" plywood. The walls will be 3/4" skeletonized ply (insulated) sandwiched by 1/4" ply. Not a ground breaking design, but I'm not here to reinvent the wheel.
See attached.

[mikeschn]

Here's how one of my trailers looked...

it's 2x2x1/8 for the chassis and 2x2x3/16 for the tongue.



Mike...

[azgreg]

Looks pretty close Mike. You think I could go without the center beam on the tongue?

[mikeschn]

Looks pretty close Mike. You think I could go without the center beam on the tongue?

If weight is critical you could. But you could also shorten the two angular beams, and lengthen the center beam and put the coupler way out front! Depends on what you are trying to achieve.

Mike...

[azgreg]

Weight is not a concern at all. I also plan on installing a tongue box.

[drhill]

A long tongue gives you another option for carrying bikes. I put a receiver on the back of my trailer too but have never used it. I don't want the bikes in the way every time I want to open the hatch. The access to the tongue box is doors on each end so again, no need to move the bikes.

[azgreg]

My wife has informed me that I have come up with a profile. It's sort of a modified Grumman 2.