186 replies to this topic

[pods8]

This is the build thread steaming off my design thread: http://www.wanderthe...hp?/topic/4199/

General design concept picture:


NOTE: First off this is a spare time project in my garage, I work full time and have a 10mo old son needing attention as well so folks will need to bear with in terms of progress, it'll be what it will be.

Personally I've always wondered the time spent doing some of the builds I've read about so I'm going to try and keep a running hours log going as I post updates (this doesn't touch on design/research time). A lot of my initial progress will likely be a couple hours here and there, which for the time being works since I have to wait for epoxy to cure. I'll just give a quick summary and a picture or two.

UPDATE #1 (5hrs in): A bulk order of epoxy was placed last week which should be arriving this Friday. This likely won't be enough epoxy to finish things off but will go a long ways while I refine the final number needed later on. Friday I picked up a load of foamular 600 that I'll be using as the core. Over the weekend I ripped a sheet of plywood into 2" strips to use in my core build, cut the bulk floor foam pieces and started putting them together. I still have some epoxy left from testing so I was able to get going this weekend with that. The first pieces I put together made me realize I needed some long pipe clams so I stopped after the first seam and picked up some clamps the next day to finish putting the other chunks together. After this cures I'll cut this into slices and add wood strips in the other direction to form a grid. I plan to sheet the floor core with 1/8" plywood which I'll epoxy and narrow crown staple down, then I'll glass over the top of it. Probably more robust than needed but off all things the floor needs to be strong.

I also made up four final test laminates since my earlier pieces were made with foamular 250, also I'm trying another fabric in there. I'll make a final decision after these pieces cure for a week or so and place my bulk fiberglass fabric order.

[ski3pin]

It's great to see the creative thought and energy going into these custom projects. Thanks for sharing and keeping us all posted!

[home skillet]

Pods8,

Congratulations on the first steps! Exhilerating isn't it? I also appreciate the fact that I am not alone in the "crazy enough to do something like this" category

It will be a ton of fun to watch your well thought out project take shape.

Boy, that pink stuff brings back some memories. PS. your garage looks about the same size as mine, I had to spend about half my time staying organized just so I had space to work.

Home Skillet

[pods8]

Well technically my garage is a good sized 2-car to start with... But the hot water heater, washer, dryer and storage is along the house. Then along one side I have my work bench, air compressor and table saw, down the other is more storage, beverage fridge, and my kegorator (which is unfortunately busted). So I've lost a bunch on the perimeter. It looks as crowded as it does in the picture because on the left side is really a partition of some misc stuff, the remainder of the foam and plywood all stacked up but I sill have a isle on the other side of that to get to the bench/saw. There are a couple strollers in the mix too. I'll be spending some time shuffling as well. Ideally though I'll clear out a few more things, start using the foam up in the build, etc. and space will free up when it comes to working with the bigger camper as a whole.

[home skillet]

......and my kegorator (which is unfortunately busted).

What the? Stop work on the camper immediately and fix the kegorator! What's wrong with you man?
Just kidding, sorta.

I pulled the trigger on the 12V rams. They will be here next week. Also, I came across a really cool 4-way control device (my Dad turned me on to it). It is made by "happy jack" and used for their camper jacks, but would work really well for the actuators for our pop-ups well too. There are other brands as well and I bet you could build one up from Radio Shack parts.

Atwood
Happijac
Reico Titan

There is a solution here somewhere.

Home Skillet

[pods8]

Haha, long story but it would likely mean building a new one, it was a chest freezer running on a temperature controller and 5 taps. Appears the coolant leaked out on it so the general thought when that happens is they are scrap. Since I'm taking a little brewing hiatus and also don't foresee wanting quite as large of a setup down the road I'm just holding off on that project.

On the actuators, I'm not so interested in wireless (however it would allow you to walk around the perimeter while lifting if you wanted) so a 5 switch panel (1 master and then 4 independent for adjustment) would accomplish the same for notably less. My big goal if I went with actuators though would be to see about doing up a PWM board so the speed of each one could get dialed in properly, then going forward there wouldn't be need to watch the 4 independently. I was doing a little reading yesterday and I think the electrical components would be fairly cheap I'd just need to bring myself up to speed on assembling/solder a board together. But I'm getting ahead of myself on that front, its just good to know there is potential options available as long as I leave space for a panel later.

[pods8]

UPDATE #2 (16.5hrs in): Hoped to be a little farther along in general, and for the hours put in but the floor is one of the more involved chunks due to the grid and multiple hard point blocks installed. Now I have to wait for things to cure for a bit so I can sand the excess epoxy/filler off the top/bottom and level things out before I lay down the 1/8" plywood sheets over things. The cooler temps make for longer pot life time with the epoxy but also takes longer to set up, if I tired to move forward and sand right now it'd just get all gummy.

So what I have going here: 1/2" plywood grid which I'll attached the plywood sheets to (along with surface gluing to the whole floor pack), this serves to make sure the two skins stay well connected to each other and don't just relay on the bond to the foam alone. The corners have wood hard points that I can attach the eventual jack brackets into (the sides will have similar hard points in the corners for the brackets). There is also a plywood chunk in each corner to distribute the vertical load if I go with hydraulic rams. There is a 10"x10" 1/2" plywood chunk recessed into the foam to mount the table base to. The other 4 plywood chunks (forward set closer to the center, rear set farther apart) are in case I want to bolt through the floor to attach this to the flat bed. There is a 3.5"x3.5" 1.5" thick block centered under the 6"x6" 1/2" plywood. Right now I'll see about using the jack brackets to mount the camper but in case that doesn't work out I've got these bolt through points to fall back on. The 2" wide flat plywood strips around the perimeter is a theme I plan to carry through the interface points between all the various panels. I plan to screw the panels together while temporarily assembled, then strip apart to do the fiberglass work in the horizontal and then reassemble. They will again allow me to screw things together while the epoxy sets up joining things together, the screw holes will be filled and covered over when I lay down the fiberglass strips over all the joints which will really tie things fully together.

[pods8]

Those test pieces on this foamular 600 foam (verse the foamular 250 I was previously experimenting with) had sufficiently cured and I subjected them to the hammer test. In reality this is asking for much more impact strength than really needed, I mean if you hit an aluminum sided camper that didn't have foam bonded on the backside (ie like my FWC with fiberglass insulation) this hard with a hammer you'd likely punch into it. But its something to shoot for.

Below is the photo of the 4 test pieces with a HARD hammer hit to the center, all performed in a manner I'd generally be comfortable with using. The 2ply piece experiences more deformation but still fared okay. Three plys did well, yes there is cracking in the matrix but not a total failure. The 2 plys over 1/8" plywood held up the best as could be expected but its a definite weight trade off.


I know the questions will inevitably fly on weight, cost, etc. so I'll shine light on the information I put together to help decide on the path for the shell construction. I weighed each of those sample pieces as I assembled them. The results below show the component weights. I had to make an assumed correction for the glass weight since the pieces are cut oversized and then trimmed after the epoxy has set up a bit. I used the published weight figures for the cloth to make the correction. I was expecting a realistic glass ratio of near 50% so the 55% is appealing and I believe realistic for these flat pieces.

Below that is a summary matrix of which type of ply schedule on interior and exterior verse the weight. This is based on a rough estimate of 400ft^2 for my shell. This is the weight before the weave is filled/faired and painted. There is no allowance for windows, fittings, etc, etc. Just gives a ballpark weight for foam panel construction on its own. Also no allowance for the wood inserts I'm doing in my build but that would be the same no matter with ply schedule I went with.

And finally the cost of just the foam, glass, and epoxy to make those shell configurations. Again no allowance for shipping, tax, application supplies, etc. These are just rough decision guidance calculations.

Enough with the caveats here's the numbers:

[pods8]

Update 3 (27hrs in): A $30 harbor freight inline sander and $30 harbor freight belt sander were good investments on this project (note if I know I'm going to use a tool a bunch I'll splurge for quality but these things will likely get used/abused on this project and not have too much other use so the HF stuff should fit the bill well). 80grit on the belt sander along the wood areas to knock that all flush and then 36grit on the inline to fair out the foam. My compressor doesn't quite keep up for continuous use of the inline but it only slowly looses ground so I can get a good chunk of continuous sanding before I need to hold off and let it fully catch up before hitting things again. I think this will come in handy while doing fairing work after the glassing as well.

1/8" ply was epoxied down top and bottom with narrow crown staples & some pavers to hold things in place in the meantime. I had one mild bonehead move in that I drew out where the wood was on the upper 1/8" ply for easier reference later but then proceeded to staple down the first sheet mirrored in the wrong direction (front to back) due to the core being in a different position after I had flipped it from doing the bottom and me not thinking about it till after some staples had left the gun. Easy enough to just transfer the marks later though so no real harm other than a bit of wasted time.

The 1/8" ply is slightly oversized right now. I'll use a flush trim router bit along the top edge and a 1/2" radius bit along the bottom foam edge to trim it up later.

[pods8]

Update 4 (35hrs in): Did some cleaning/rearranging in the garage and used up some of the stacked materials so I'd free'd up space to move around a bit more. The overhanging 1/8" ply on the floor was trimmed, there were some gaps along the edge between the core and plywood so I filled those in with a thickened epoxy mixture and will need to resand/smooth all that out.

The floor creates a nice work platform in the meantime as well. I quickly did the rough outline of most of the lower walls and cut/fit the chunks of foam in the sections that aren't question marks. The other areas have windows/heater vents/propane hatch, etc. that I need final dimensions on so I can fit the wood/foam accordingly. Once I know that I'll glue the cores all together and fair them out to prep them for glassing (they are just friction fit, taped/clamped together right now). But it is good to see some shape coming together.

Sections mocked up together


Broken back down for the day