Teardrops n Tiny Travel Trailers

For your consideration...

I'm building a woody, and for various reasons don't want to have "external" trim. Steve F. does a great job with his, but I'd like to reduce the amount of lumber involved a bit. I really like the way his seal "captures" the sidewall, so here's what I'm thinking of doing with my insulted wall (not to scale ):



From left to right, the black is 1/4" ply external skin.
Pink is 3/4" pine framing, routed out for the...
Green is 1/4" ply, filling filling in the routed out area.
Blue is the inner, 1/8" skin.
Red is a 3/4" ply hatch rib.
Two lines extending to the right are the hatch skins.

So...the construction theory is that I'll rout out my framing to accept the 1/4" ply, and then apply the inner skin. I've got 3/4" of external skin and framing outside of the groove on the hatch, and 3/4" of hatch rib to capture the tongue. Obviously, I'd have to widen the groove slightly so it doesn't bind. That white space above the tongue is where the rubber seals would go, probably about 1/4" deep.

So I've got a 3/8" wide tongue, 1/2" tall, going into a 3/4" deep groove with the seal taking up the rest of the space.

What do you think? Does that sound reasonable?

Thanks!

David

Hi David, a hatch seal with no exterior trim, huh? I don't know about that design you posted, the tolerances just look a bit close. It sure looks good on paper, but I just went outside and wiggled my hatchlid from side to side as it was closing and to try to get it to engage in such a small slot just wouldn't work on my rig. I opted to have overhanging trim shed the water and it even works well underway in a rain storm. Hey, don't let me sway you from your design, but unless all of that wood and joinery is coated with epoxy, it might cause major problems down the line.
Roly........lets hear from some of the pros....how about it Doug-Dog?

David,

Strictly an amateur;
I do have external trim on my TD, but I did my hatch seal in the configuration you have in your picture, more or less. I left a 1/16" gap on both sides of the side wall in the "C" shaped slot. It worked pretty good, but has rubbed in one spot about an inch long on one of the side walls, not enough to take off the finish though.

Roly & Steve...good input, thanks!

Yeah, the tolerances are fairly tight in the drawing...I'm not that good an artist

Steve F's design has an 1/8" gap on each side of the tongue, and I've got enough wood there on either side to widen it as necessary. I'll probably shoot for the 1/16", and go from there.

And yes, it will be epoxy-sealed.

David

Don't forget, if you're going to coat it with epoxy.... you'll need more wiggle room. A couple of coats of epoxy on all pieces is about an 1/8" thick easy.

Don't ask me how I know...............

Hmmm...sound like a good opportunity to learn from the mistakes of others, rather than make my own...

But I bet if I epoxy the thing shut accidentally, it won't leak a bit!

Good to know...thanks John.

David

David...that will work fine. On the lip that fits up into the hatch, I have 3/8" of material stickup and it's 1/4" thick. I epoxied up all the exposed edges to the point that when painted, it appears that it is a piece of molded material, has to be done on the hatch also. I ran the rubber weatherstripping on the hatch side in the groove. I can hit it with a hose and it doesn't leak. Haven't had it out in a driving rain however...haven't had any rain since April. Just make sure that you leave enough room to add the weatherstripping. It needs to have the same gap all along the hatch. Too little on the top and the bottom won't seal. Doug

Thanks Doug...I wasn't real sure how thick to make the tongue part...Your 1/4" seems to be working, I won't worry too much if I have to thin mine a bit to allow for more sealer and/or alignment issues.

I was also thinking about tapering the tongue to help in the alignment...that'll be something I'd do after installation on an "as needed" basis, but it's good to know I can go thinner if need be.

David