I also owned a Skamper 086 which had the problem with the rear lift arm corners twisting up. All the torque from the torsion bars are on those corners. The 1x4 wood frame which the corner bolts are bolted through is not strong enough to keep the bolts from wallowing out from this torque and flexing up over time.
On the inside of the frame, I used a piece of flat steel, 1-1/2" wide x 1/4" to span the distance between the corners. I measured the distance between the bolt holes in the corner angles and drilled the flat steel so the new bolt holes would re align line the corners correctly. I think I installed this metal strap between the corner angles and the wood frame to help reinforce it. (it was about 12-14 years ago I did this)
About the roof sag and leak, I never had that issue, however a friend had to remove his Skamper roof so he could rebuild it. He used ratchet straps to span the lift arms while the roof was raised. Tightened the straps to take the pressure off the roof brackets and with a bunch of people lifted the roof off so he could rebuild it in his barn. The roof is heavier than you would think! I think we had about 8 people to lift it off.
I was not present when he rebuilt the roof, but I know he replace most of the perimeter framing which was rotted and was the reason for taking it off. He also did the reinforcement flat steel on the rear corners while it was off.
Finally got the time to start demo this weekend. I didn't have any helpers, so I had to use some ingenuity to remove the top to work on it. I removed all 150-200 screws attaching the top of the canvas to the roof, and folded it inside the camper.
I "engineered" a 2x6 ladder truss that ran from the back to the front, skinny enough to fit in-between the collapsed heco lift bars. I lowered the top down onto the truss and detatched it from the lift bars. The truss is only 33" wide and the top is over 84" so it was a very precarious perch. (I almost lost the whole roof over the side.)
I then attached two more 2x6's to the front of the ladder truss and placed the other end in the bed of a pickup truck, effectively creating a slide. I then got into the camper, lifted the roof and slid it down into the pickup. The pickup was pulled forward and the slide boards fell out of the bed, leaving the camper's top right side up, resting on the pickup's bed rails.It weighed between 200-300 lbs and I would have much rather had help for the removal. I would expect most of the weight was from being waterlogged, though.
I then tipped the top out of the bed, standing it on its rear edge. Here's what I'm working with:
Laying down now:
Upon removal of the roof vent, it was obvious that prolonged leaking had caused irrepairable damage. The roof's top surface was fiberglass, with styrofoam and 3 plies of some kind of wood, including the finished white material toward the interior. I have not yet found any wood bows going from side to side. It appears the main structure of the roof was held up with pixy dust and prayers. I can't blame these materials for failing due to bad design. The fiberglass was glued to the styrofoam, and the styrofoam was waterlogged. The super-thin plywood could be de-laminated by hand by a toddler. I decided the best way to repair this was to build brand new.
In forming the sides, they made relief cuts in the styrofoam with a table saw or similar tool and made a radius bend. They then ran approximately 3/4"x 5" strips of plywood for all the sides, The plywood was not strong enough to deal with the substantial torque created by the heco lift system, and the mounting points twisted and broke through the plywood. The 8' strips also had to join somewhere because the top is just under 13 feet long. To join them, they placed two staples in them and placed the joint right at the forward mounting point of the left system. I could not imagine a worse way to do this.
The aluminum trim that meets with the lower part of the camper has a 1" track. To span the difference between 3/4 and 1", they placed a 1/4" plywood furring strip in there. This created problems when the track was screwed to the sides, because the screws were barely biting into the 3/4 plywood.
note furring strip:
and 1/8 hole drilled within 1/16 of the edge of the plywood (for some reason this didn't hold...:
moving on to the lift system, as dbrojr mentioned, they were spring assisted via a hexagonal rod about 5' long. The spring action wants to force the prop bars vertical to the ground, and I got a lot of resistance trying to remove them at any angle other than vertical. I ended up putting a hole in a cabinet despite the warnings. The angle shown is the way it needs to be removed:
close up of where the rod mounts, note the hexagonal receiver and how the torque has twisted the rear mount, creating the sealing issues shown in the next two photos:
I think v10scott's suggestion of linking the back two mounts with steel would eliminate this twist. A stroke of genius, good sir!
hex rod-note not all the bevel cuts are the same, I may have issues during re-assembly because of this...
the forward mount (just a pivot point, no torque here):
The plan, for now...I am open to any and all suggestions, that's why I'm posting this :
I'll build the flat part of the roof with 3/4' tongue and groove plywood, a little over 3 sheets worth for a total length of about 13'. The sides will be two sheets of 1/2" plywood glued together for a total thickness of 1" (to fill up that aluminum trim) with the seams staggered. I'm not going to do any fancy curved corners like the manufacturer did, because I don't have time for that. Any sharp corners will be routered down with a 1/4' round radius.
I will cover the top with a single sheet of TPO roofing membrane. Here's the guy I'll buy it from (craigslist ad- 10'x15'=$175). I am not familiar at all with the material, but the seller says the manufacturer waranties it for 10 years, and can be installed by a layman like myself. ANY INPUT??? I'm planning to pick this up this Wednesday.
This looks like a little bit of a job, but, that's what is interesting about it.
The roof looks to be made of beaded polystyrene and probably 1/8 inch plywood. The mfgrs. do this to make them as light as possible. It will do a great job if you keep the water out. This is called a stress skin panel. Good info is available on the NIDA core website.
I don't think you will like the weight if you put 3/4 ply back on, although it will be quit strong.
I re-built a Palomino 8801 with a leaking roof and de-laminated glass last fall. The roof is an 8 by 16 foot, 2 inch thick beaded polystyrene stress skin with 1/8 inch ply on both sides. The outside edges and around the openings are 2x2 wood to hold screws. In addition, I think it has 2 - 8 foot 2x2 ceiling joists.
I'm about 170 lbs. and I can jump up and down on it. It is really strong and light weight.
Also, in answer to one of your questions, I used polyurethane glue (Gorilla glue) to put the ply on the polystyrene and to put the fiber glass back on. It uses moisture to cure and doesn't need air. I experimented with other types that claimed to be for fiber glass but had bad results. If you can find a generic brand it will be a lot cheaper.
I'm afraid the 3/4 plywood rout is going to be too heavy...the lift system is only rated for around 200-250 lbs if my memory serves me correctly.you will strip gears and break lift cranks.you may be able to use 1/4 inch ply though w/ 2x2 outside perimeter and down the center.
The roof is actually built using glue and foam board sandwiched between the aluminum/plastic outside skin and the paper covered cardboard interior panel,then its put in a forming press and the glue dried with inferred heat and that bonding is what holds the shape.
left and right=2x155"x4.5"=1395 sq inches or 9.6875 sqft.
front and rear=2x83.5"x4.5"=751.5 sqin or 5.2188 sqft
total square footage: 14.9 square feet
-stock weight (3/4")=34.9 lbs
-proposed weight (1")=46.6 lbs, an increase of 11.9 lbs
20 lbs (estimated) TPO roofing and caulking
15 lbs (est) aluminum trim
5 lb (est) steel stringer to connect the rear receivers
Giving me a pre roof weight of 86.6 lbs, with 163.4 lbs left to play with.
Looks like 3/4" is out of the running.
I'm now down to sheeting it with 1/2" and calling it good,
1/4 ply outer skin with 3/4 ply bowes every 2-4', and the bays filled with styrofoam board, and another 1/4 plywood layer toward the passenger compartment
Anyone care to weigh in on the top design?
I am also looking for guidance on the TPO material vs EPDM vs bedliner vs elastomeric paint vs torch down tar roofing.
I'd do the same as the side walls, thats how mine was. Its 1x lumber and then thin covering on each side. I'm giving up on the pop can thin aluminum and instead of cheap paneling I'm using 1/8" plywood on each side of 1x lumber (which is 3/4") so it adds up to 1". Home depot had 3/4" insulation with a slightly higher R rating than lowes so I used theirs (pink stuff). Its actually quite strong.
The roof was an upside down L shape made with 1x8 for the sides and 1x4's on top of those. I could tell that they sat the top of the roof on the sides as the thin ceiling covering was sandwiched between the wood. So when I replaced the 1x4's all around the outside I made two going across the center, one centered at the front of the lift arm mounts and the other centered above the overhead cabinets. I intentionally looked for two boards that were bowed in the middle and but that upward to give a slight rise in the center, then curved the front and rear to match.
I glued the plywood pieces together with Gorilla Glue. I bought two tubes of 60 minute Ace Apoxy for the wood to aluminum job. presently I am fitting the parts together to see if it all fits. A dry run. One probably I am having is that the side wall seals do not mate with the rear gasket. I saw that when I started. It is off on both sides about 1/2+ inch. If I move the rear Al. channel down I would have to add a section 6' x 1" of skin so it would close the gap and rework the end caps. What a pain!!!
I finished up the demo of the top this weekend and have plenty of pics, but no way to upload them right now...
I also bought all of the wood and insulation for the project. On the sides, I've pre-cut the plywood in 5 1/8" strips that I'll laminate together. The question now is, what's the best glue for laminating two sheets of plywood together? By laminating, I mean stacking two thicknesses of 1/2" plywood together for a total of 1" total thickness. I'm doing this because I wanted to stagger the seams on the longer pieces 13' run using a 8' board.
I bought liquid nails in both the HD and regular strengh varieties, and I also have some Gorilla brand wood glue at home. Any suggestions between these three products?