"Hypno-Toad's Command Post." Door and windows in!

[cracker39]

For Jeff's question about strutural integrity with only an exterior plywood skin, I emailed him this answer but want to post it here for others to see and comment on.

As for my opinion, I believe that the framed up sides, ends, and top, with large skin pieces of plywood attached, all assembled, provide all of the structural integrity that is needed. With the cabin attached to the frame, you have a rather solid "box" that doesn't really need the interior skin to help improve it's stability. I'm not an engineer, but have observed the strength of a simple cardboard box in resisting being warped or twisted when it is fully enclosed (top, bottom, sides taped shut). You can bend or twist a single piece of the cardboard, but not the assembled box...try it.

I think the appearance of the interior skins, as you describe it, would be pleasing to the eye as well. Being able to remove a single piece to get to something in the wall or ceiling would be an advantage that I hadn't considered. Good thinking.

[jeff0520]

Thanks Dale, I appreciate the input.

[Forrest747]

I agree with cracker and I am an engineer. (its the reason i cant typoe) if the structral strength is dependent on the interior wall than I am hosed. If and when i do this again i will defitialy do it different than i did this time with all the skills and knowledge i earned on this one. its a tank defitaly overbuilt.

[jeff0520]

Thanks Forrest. I'm glad to hear all the agreement. I kind of said the idea, thinking out loud, and Laurie jumped on it with "Ooh, that would be pretty! Do it that way!" before I had thought through whether it would work or not. she's so excited about it, I'm glad I don't have to tell her it wont work

[jeff0520]

Got a swing away tongue jack installed, but it's just too gawdawful hot out there to stay out long.

[pappaw]

looking good!

cheers

[Vedette]

Too Hot, Too Much Rain........................???
Sounds like you guys need to relocate.
Life is too short to live some whwere with "Bad Weather"all of the time.
On the Bright Side, soon you will be able to get away in your new trailer.
Keep up the good work!

[jeff0520]

Too Hot, Too Much Rain........................???
Sounds like you guys need to relocate.
Life is too short to live some whwere with "Bad Weather"all of the time.
On the Bright Side, soon you will be able to get away in your new trailer.
Keep up the good work!

No doubt spring is often a bit too soggy here, and summer is gawdawful hot at times, but fall and winter are BEAUTIFUL. Thanksgiving at my place is usually a picnic in the backyard. Christmas is sometimes an outdoor event too. The best times to camp here are September/October in the fall, and April/May. Even in the hot part of summer, if you get up the the deep woods, up in the mountains, it's often not too bad, especially if there is swimming available.
Give it another 6 weeks and it will settle down. Then I'll be able to really get some things happening out in the build shop.

[aggie79]

Beginning negotiations with the wife on interior design now that wall layout and framing time is here. The 1/8th hardwood plywood we bought for the outer skin has such a pretty face on it, that we are thinking about using that for the inner skin as well, and just sealing it up with a nice urethane to make it waterproof. What I'm wondering is this, How important to the structural strength is the inner skin? The reason I ask this is that I came up with an idea to make the inner skin easier to install, and very pretty as well. I'm considering cutting little panels that mirror the frame underneath, and sealing them with urethane, then putting the pieces over each frame section. Then taking 1 1/2" x 1/8" lattice strips, and staining them a few shades darker, and covering all those seams sort of like batten boards. I think it will be a very attractive, natural look. This will also allow individual interior panels to be removed to do repair work or modifications later.
The downside to this idea is that if the interior skin is a major part of the structural strength of the wall, I might be compromising the structure too much by installing the interior skin in roughly 14" by 14" pieces. Opinions anyone?

Don't worry about the interior skin being required for structural strength.



In the picture above, I only had the interior skin on and not the exterior skin. The teardrop shell is supported at three points - one in the middle front and two at the sides in the rear. I placed a 340 pound load inside of the trailer - my wife and I crawled in the teardrop - and there wasn't any sag or deflection.

[jeff0520]

Thanks Aggie. That clears up a doubt about another issue as well. Looks like my design changes will work out fine

[jeff0520]

I managed to get a good bit done before it got up to heat stroke inducing temperatures today. I completed the install on the tongue jack.



Now I can roll the trailer out of the portable garage and under the shade tree. MUCH nicer out there
I also laid out the side profiles and got them cut today.










After that, I realized I was so soaked in sweat that it looked like I'd been hosed down. It was time to come inside into A/C for the day!
Tomorrow morning I get to begin cutting the frame parts.

[parnold]

Lookin' Good!

Gotta be careful in this heat. I was up at 6:30 to work on my trailer, by 8:00 I gave up. Now it's all A/C and pool time for me!

[jeff0520]

Still terribly hot out there, but I did get a half a dozen roof spars ripped today. Also filled my tongue extension tube full of foam so wasps can't nest in there. It wasn't much, but every little bit helps

[Forrest747]

Hypno as far as the engineering advice I wasn't paid in cold adult beverage and made no on site evaluation. Your on your own. Now if a coke or Dr pepper gets FedEx to me I will sign what ever you want.

I know whatcha mean about the heat. I went through easily 6 gallons of ice h2o. Even had it melt in blowtorch fashion. Came in soaked from sweat as well. I much perfer winter than summer especially in the garage

Feels good to whhel it around. Keep up the good work.

[jeff0520]

I spent today's build time drawing the shapes of the wall edge framing on the wall plywood. I also got my main roof spars cut today. I still have to make the multipiece ones for the corners and roof seam lap joints, but the easy ones are done. Finishing the spars will allow me to trace around the ends of the spars to mark the notches in the wall edge framing. Once all the spars are cut I'll be able to start cutting and laying out edge framing.
I still need to figure out exactly where I want the windows to sit on the sides, but I figure I'll unbox one of the windows and just lay it on the plywood profile and move it around till I find the best spot, then I'll trace around it and fill in the frame from there.
No pictures today, because a pile of roof spars laying on the floor just isn't that interesting.