M116A3 Build

[S. Heisley]

If you got the windows from Grant, send him an email or PM and he will most likely tell you how best to install them. He's good about things like that. However, he just got married a week (or so) ago and may be on an extended honeymoon. But, it looks like you could wait a while and work on other things until he answers.

[lfhoward]

Hi Sharon,

Now I vaguely remember Grant telling me these didn't come with trim rings, but for $10 each, I didn't think that would be a problem.

I'll do a little research and see what I can find. I am pretty sure 14x21 radius corner windows are pretty widely available, so maybe trim rings could be bought for not too much. Noseoil also said he was building his own trim rings, so it is nice to know that is an option too. Worse case scenario, I'll contact Grant when he gets back from his honeymoon. Plenty to do in the meantime to keep me busy!

Hope you had a good weekend.

[lfhoward]

Today I got the rear wall framed (fixing the issue with the rear door brace), as well as built the side bench skeletons in the shop. The benches seem to fit well over the fenders (as much as I could tell in the dark). I'll tack them in tomorrow if there are no measurement issues that crop up.

Once the benches are in, the framing of the trailer will be 95% done. The rear door and side utility doors will need to be built, as well as an interior cabinet unit, to bring it to 100%.

Here are the next steps I have in mind:

1) Run the wiring for the AC & DC systems -- it would be nice to have interior lights and a fan to work by, as well as electrical outlets to run my tools. And it will be easier to route wires without walls on yet.

2) Attach the exterior plywood -- the sooner I can get it skinned and relatively watertight, the less I will worry about rain. I plan to get the exterior walls on before insulating and tacking up the interior walls, which I know is the reverse of many teardrops on here. But I have no garage to store the trailer and am relying on a tarp.

3) Build the Battery cabinet and cupboard unit that goes at the head of the bed.

4) Fit insulation between the wall framing and then put up the interior walls.

5) Build the doors.

6) Locate and purchase some 5' wide aluminum sheeting (0.04 inch) and skin the exterior.

7) Install windows.

[lfhoward]

Bench frames are now installed.

I got the AC side of the power grid up and running today (in order):
AC Power inlet (drivers side)
15 Amp AC fuse holder & Kill Switch
CGFI outlet (where the battery charger plugs in)
Transfer Switch (where the inverter will also supply AC)
2 interior wall outlets
1 exterior weatherproof outlet (on the passengers side)

I'm able to run power tools from the trailer's electrical now, which is much more convenient.

Next up: DC power system
Battery Charger
3 batteries
Inverter
Fuse panel
Interior & exterior lights
Fantastic fan
Wiring and switches

Or, at least I will run the DC wiring so that I can put up the walls.

[lfhoward]

The nuts and bolts of the DC electrical system are in, so I can light the trailer at night and run the fantastic fan to keep me cool while I work. The inverter will have to wait for another day, but I can just plug the trailer in to the AC in my workshop using a long extension cord, and run my power tools from outlets in the trailer.

The trailer has a lower front wall and a passengers side wall now! Very excited. Tomorrow I will get the rest of the walls and the roof on, with the help of my neighbor, Tim.

I did end up using Titebond II after all to help secure the walls. I brushed a coat of it onto the beams after I had the wall plywood all cut out and pre-fitted. (The trick was to use enoug TB so it didn't dry too fast but not so much that it would drip.) Then, I put the wall in place on the frame and quickly tacked it down using 3/4 inch brads from a nail gun. (Using a nail gun is super fun.) The nails did a good job of pulling the wall against the beams, so that the glue contacted both surfaces. Next, I drilled holes using a bit-countersink combo, then permanently fastened the wall to the beams with 1 inch wood screws spaced about 8 inches apart. The wall assembly is super strong! Pics tomorrow.

[S. Heisley]

You're probably going to think I'm nutso-cuckoo, but, I found that wiping down the beams/spars with a damp sponge, followed by the TBII (or III) would help the glue work better and lengthen the set-up time. I read it somewhere and it worked like a champ!

[noseoil]

I hope you got the insulation marked for cuts first, before skinning the outside of the wall! Much easier to use a magic marker than a tape measure to do it.

The idea of wetting down the wood a bit with water is a good one to get a better bond. It will help the glue penetrate the surface a bit more & key into the fibers deeper. Here in the summer, my glue almost dries too fast to use it. It skins over in a minute, so it's slow going & larger panels are out of the question in the heat & 10% humidity.

Those walls must be solid as a rock with the first skin in place. Wait until you have the second skin glued up & you'll be amazed at how rigid the structure becomes. Do you have a guess yet about the all-up weight when everything is loaded up & ready to roll?

[lfhoward]

Dang, that would have been a good idea to draw frame on the insulation pieces! Wish I had thought of that! Oh well, I can measure them. I have a stack of 2 foot by 4 foot styrofoam slabs, 3/4 inch thick. Super cheap and very effective. I'll use them everywhere but the electrical compartment where there might be sparks.

As for glue, it's hot here but very humid too. The time it takes for the glue to set seems to be just right. I was ready to wet down the walls if I needed to, but everything seemed to work just fine.

In terms of weight, I'm not sure. The trailer is about 1000 lbs empty, and can carry another 2000 (for 3000 gross weight). If I can keep everything under 2000 lbs gross, I'll be happy. 1500 lbs would be awesome, but I don't know if that will happen. I will take it to a scale at a truck stop eventually to satisfy my curiosity! My Jeep has a 5000 lb tow rating, so I can pull it, but it will be happier in the long run if the trailer stays on the lighter side. I considered swapping out the military axle for something lighter, but I would lose my brakes, parking brakes, shocks, and HD springs... I want this trailer to be rugged as possible! So I know it is a bit heavier from the start than some of the other military conversions on tnttt.com.

[lfhoward]

As promised, here are pics! The plywood has gone up fast, and what you see here is about 2 afternoons worth of work. I took the pictures as the sun was setting, so they are a little dark, but you get the idea!



A little closer in:


One of the front utility cabinets (passenger's side):


The weatherproof outlets for the "kitchen" on the passenger's side:


A look inside thru the back door:

You can see the compressor for the nail gun, plugged into the trailer's AC outlets. Super handy to be able to instantly tack the walls on after painting glue on the frame.

The electrical cabinet on the driver's side (also note the shore power inlet near the fender):

I have my battery charger/converter running the lights. Batteries aren't installed yet.

Speaking of lights!


The porch light is very handy also.


Here's what it looks like when off:

[lfhoward]

A few questions for folks:

1) I am planning on using silicone to seal the gaps between the plywood and the metal deck (like I did between the floor sills and the metal deck). Would you also recommend sealing the joints between plywood sheets the same way? Or some other way?

2) Some folks shellac the entire outside of the plywood (or fiberglass it, epoxy it, or something of that nature) to make the whole tear water resistant BEFORE putting the aluminum skin on-- sort of extra insurance. ...BUT I have heard from a teardrop master that it is better NOT to seal the wood, because wood needs to breathe, so that if it ever does get wet, it can shed the moisture and dry out (not rot or mold). The aluminum does all the waterproofing. Are there pros and cons I am not thinking of? I am leaning toward letting it breathe.

3) In terms of aluminum, I am looking for quotes locally and don't have it yet. When I do... When installing the aluminum sheets, I am thinking the best way is to let them "float" and only screw them down at the edges (with silicone sealer under the edges). Good idea? I have aluminum edge moldings for the corners and door openings that I can screw down over RV putty tape.

Thanks for considering my list of questions! Just thinking ahead to the next steps, and want to be sure the process I am visualizing makes sense.

Cheers,
Lauren

[noseoil]

Don't use silicone on the wood edges. If you do, the next layer of anything won't stick to it. I'm going to use some Sikaflex to do the skins like you are, but not silicone. Over time, silicone might work loose in places & if it does, it's impossible to stick anything else to it once it sets up. I think PL Premium urethane adhesive would be a better choice for what you're doing. It's in most home stores & about $5-$6 a tube. Well worth the money. Use nitrile gloves when working with it & clean up spills with paint thinner before it dries.

If you live in a cold climate where the condensation can "wick" through the wood in the winter, it will hit the outer skin of aluminum and form ice crystals, then thaw out and could start some rot over time. I've sealed the inside of mine with urethane, a couple of coats, which should contain any moisture from respiration during sleep. You need a fan running for sleep in the summer, or at least something open at night since it's going to be virtually air-tight once it's finished, even in the winter. I may still do the outer wood covering (more urethane) prior to the aluminum skins being set in place. Most likely I will, just for peace of mind in the long run.

I'm in a dry climate most of the year, so not as worried about rot and moisture as some. The cars here in Arizona don't even rust, they usually die of old age first. Any place moisture can seep in and get the wood wet will contribute to rot starting in the wood. The more sealed up it is, the better in general.

There are too many stories I've seen about rotten walls under aluminum to not think about it a bit. The main problem seems to be bad joints in roof edges or seams, walls, & decks at the frame rails & fastener openings which can collect water from running on the road in a storm. Doors with leaky edge seals are another problem which can add water where it isn't welcome. The main thing is to keep the water out & not let it in.

[lfhoward]

Don't use silicone on the wood edges. If you do, the next layer of anything won't stick to it. I'm going to use some Sikaflex to do the skins like you are, but not silicone. Over time, silicone might work loose in places & if it does, it's impossible to stick anything else to it once it sets up.

Hmmm. Looks like I may have to do some damage control before I can seal the walls.

I used GE Silicone II under the foundation, between the wood beams and the metal trailer deck. That's permanent and can't be undone. Not too worried about that seal because I bolted the wood down. Here is the wood foundation before being siliconed and bolted, but you get the idea.



What I am worried about now is the silicone that got onto the 1/4 inch of trailer deck just outside of the beams... that now has wall plywood above it. Here is one of the worst areas showing a thin coating of silicone on the deck under the wood. Wish I had masked the deck off with painters tape beforehand, but I didn't think of that. Or that I had removed the silicone on that 1/4 inch strip of deck prior to putting on the exterior ply.



The plywood walls can't come off now either. They are glued with TB, nailed, and screwed on. That gap is going to be hard to seal now. Well, I won't do that again on my next trailer!

I realize now that nothing will stick well to the silicone on the metal deck. Even more silicone won't seal all that well over cured silicone.

So, would you think I should use more silicone in the gap and hope for the best, or try to get a sanding wheel into the gap to try and grind the silicone off the metal surface? Once the silicone is removed from the surface, Sikaflex sounds like a much better way to go.

Bummed. I read lots and lots of posts over the last year and still missed this issue with Silicone. Thanks for the info!

[noseoil]

Not the end of the world. Just keep going & change adhesives from this point onward. No reason to go backwards when you can still just go ahead.

Use the PL & figure it's going to work out OK. It will still make a seal on the newer stuff so no worries!

[lfhoward]

Got to put something in the crack between the wood and metal deck, but the metal deck has a coating of silicone. Will the PL stick there without getting the silicone off first? I have access to a Dremel with sanding wheels... Could try to sand the silicone off the metal surface 1/4 inch back from the edge, inside the gap. Necessary? Or overkill?

Thanks for the encouraging words!

[noseoil]

Overkill to me. Just squirt the PL in place & bed your wall panels in it. The PL will seal up the end grain from moisture pretty well & once it sets up, it will make a good bond.

I wouldn't get too carried away with sealing, waiting, scraping & then setting the walls. Just squirt & drop the side panel in place to cover the bead. If the void gets filled and the end grain is filled on the panel, there's no room for water to get into that edge. Keep it simple......