Lifting roof XPStream - making improvements

[dales133]

Yea my scales are metric too. I came in just under 15kg.
I recon ill add probably 3 more or there abouts finished

[OP827]

Finished rough sanding then faired the roof with 3M Premium filler, made a poor man "onion board" (to do the filler mixing) out school paper stack by gluing the edges with TB2. Next is sanding. Did a better job with fairing and mixing this time and should be no issues with sanding

Local supply shop is selling this "onion board" for over 30$, looks like this :


My home made "onion board" to mix the filler looks like this and works just as good:

[dave campbell]

what an awesome project !! i'm contemplating an epoxy layer on my foam (at least the seams ) so i will be consulting this thread for sure. it's great to have you following my build and i wish you luck and a smooth build

[OP827]

what an awesome project !! i'm contemplating an epoxy layer on my foam (at least the seams ) so i will be consulting this thread for sure. it's great to have you following my build and i wish you luck and a smooth build

Thanks very much Dave for kind words and encouragement.
Let me know if you decide to work with epoxy, I will gladly share what I have learned during my build.

[OP827]

Two days later, sanding the roof top is done. Happy with how fairing worked, should be good for roll-on primer and paint. Decided to load test the span a bit . Put foot by foot foam pieces at the edges as a span support and lined the surface with 1/4" plywood to protect the surface from accidential damage or dents. Here is my daughter standing accross the span. Prior to that I crawled over the span myself for a test, but without taking a picture . Now need to prepare squares and other stuff to permanently fix lower front and walls to the floor.
Thanks for reading.

[OP827]

No progress so far as I decided to step back and rethink the front end lifting mechanism details. Back end is simple and straight forward. I originally was going to use electric actuators in all four corners. Although I got four 18" electric linear actuators purchased, lately I decided not to use them, mainly because of reliability and then potential structural damage concerns.

The front end roof lift design, as far as I know, has no known or off-the-shelf solution. It needs to provide parallelism in the front roof end lifting, still have some front-back rocking freedom for movement when the back is lifted first (same or similar to Gobur Caravan lifting back or front wall) and also I want to reduce the muscle lifting force needed by using gas struts so a common individual of not much strength can easily set the trailer up, basically like lifting the gate in SUV car type of lift.
Studying deeper into mechanics and such. Thinking of scissor lifting with some inventing twist, combination of guide rails and/or sliders and gas struts. I just want to come up with the design that is not too complex to implement out of commonly available materials like aluminium profiles, gas struts, possible rollers, sliders or UHMWPE for sliding inserts.

If anyone has any knowledge and experience with such design, please let me know.

Thanks for looking.

[Atomic77]

I'm enjoying your build and your progress. Looks like you got the filler situation worked out. Keep up the good work!

[OP827]

Thanks Michael, your recommended filler has worked great. It really produces a nice surface. I figured out how big of a batch and how to mix it. The roof piece is big as you can see, but I could finish it quickly enough not to get tired too much. Most of the sanding of the exterior was done by hand with long board. There are still a few grayish spots left from a guide coat, but I decided to leave them as is, without second time filling and sanding as I feel (by hand) the spots are so shallow and minor for what the roller paint with some texture will easily fill and cover. I am not going for a car like finish, as I know that the trailer sides will not be as good of a surface as roof due the method I used to build them, but I think with roller texture it will be close to a common panel trailer surface finish. Cheers!

[OP827]

A three point bathroom scale weight with frame, two wheels, floor and roof piece is at 247+267+99=613 lbs so far. Roughly estimating of the total dry weight trailer be in 1200 lbs area.

[OP827]

Back to the build. Glued up panels for ~13' long lifting roof sides today. There is quite a bit of extra foam material, they will be cut with a curve on top to match the roof, later. I used planer on the foam again and cut groves in the foam pieces edge for 1/8" ply inserts so when glued up they are more or less precisely aligned. Those panels must be the last big panels I needed for the build, it means I no longer need the big floor as a working table. Plan to rough cut the roof line with a good margin then laminate them flat then start with permanent installation of walls. All the best.

[KCStudly]

I see hard edge frames, too. Nice work!

[OP827]

Thanks KC, and yes I plan on protecting all foam edges with wood. While the glue dries I continued searching for better methods to reinforce epoxy FG lamination, provide stiffer surface, and help to avoid delamination at the same time.

[KCStudly]

Is it really needed?

[OP827]

Is it really needed?

I think some means of attachment other than weak foam surface is needed, yes. See this build experience with epoxy FG delamination issue: http://www.wanderthewest.com/forum/topic/4474-pod-homebuilt-foam-core-fiberglass-skin-pop-up-camper-build-thread/page-15#entry113185
The builder wrote in his post: "...First thing I need to do is repaint the grey part of the top half to white, the grey when hit by full CO sun was getting quite hot to the touch (much more than I would have expected) and the nose of the camper near the front of the garage had a couple delamination bubbles occur (the previous house was a north facing garage so it didn't every get full sun streaming in)...."

That is also another reason I will use white paint.

[tony.latham]

Is it really needed?

I think Burt Rutan was/is the master of moldless construction (using foam/fiberglass/epoxy). And I don't think he did anything to the foam surface of his remarkable EZ series of homebuilt aircraft––other than sand the foam prior to the fiberglassing.



The tiny scarfs you've cut just have to prevent any delamination. I don't think any of Burt's builds had any factory surface-finish left on the foam prior to fiberglassing. I'm sure he dictated in his plans on what grit of sandpaper should be used.

Quite the home-built birds he engineered!

Oh, and I'm really impressed with your build.

Tony