I'm still having trouble understanding the physics of movement between the frame and stock pickup bed, especially as it relates to frame tiedowns.
My current setup is a stock 87 F250 PU bed with Happijacks that anchor to the front of the PU bed and to the rear bumper.
As the bed twists so do the front tiedowns, but the rear is fixed to the frame. Why doesn't this induce excessive stress to the camper?
It seems even more stress would be exerted by front frame tiedown systems like Torq's.
I don't want to hijack my own thread, but this will help me decide how to design my custom flatbed.
If you go with Torklifts or make your tiedown mounts like them, front and rear become part of the frame. Some manufacturers, and people here believe Torklifts are superior for that reason.
'06 F350 Lariat Supercab SRW, 6.0 PSD 4x4 Long Bed, Intake Elbow, Walker Big Truck Muffler. '06 Host Rainer 950 Double Slide, Fastguns. Firestone Air Bags, Rancho 9000s, Vision 19.5s with Hankook DH-01 245s, Energy Suspension bump stops.
On all of my pickups, the beds were/are bolted solidly to the frame. If the frame flexes, the bed flexes an equal amount. There was/is no rubber grommet cushion between the frame and bed, therefore, the bed doesn't flex any less than the frame.
Reddog1 wrote: My TC is mounted to the frame of my truck. I have the Stable Lift. It does not rely on the truck bed in any way, for tie down.
Not technically true. Stable Lift still relies on the bed's walls to keep the camper centered on the truck and while they semi-clamp the camper to the framerails (with the bed in between) they are not SOLID mounts and still allow for flexing/movement between the truck and camper.
2007 F350,SC,LB,4x4,6.0/Auto,35" tires,16.5 Warn,Buckstop bumpers
2007 Outfitter Apex9.5,270W solar,SolarBoost2000e,2 H2K's,2KW inverter,2 20lb LP on slide out tray,4 Lifeline AGM bats,Tundra fridge
95 Bounder 28' ClassA sold
91 Jamboree 21' ClassC sold
DiscoChicken wrote: I've thought of this idea too. A flat bed raises the base of a tc above the wheel well, thus making it too high IMO. Resting the tc on the frame OR building a flat bed on the frame with wheel wells is the best of both worlds.
That is a well thought out setup but the camper is still mounted higher then it would be in a pickup bed and the wheelwells extending above the deck still limit the width of the TC that can be used. It would be a great platform to build a custom camper on though.
jimh425 wrote: If you go with Torklifts or make your tiedown mounts like them, front and rear become part of the frame. Some manufacturers, and people here believe Torklifts are superior for that reason.
Even with the torklift system there is still a bit of wiggle room for flex and is not the same as bolting down the camper directly to the frame . The frame mounts are extending out from the frame 18-20 inches and are pinned , not totally rigid . The tiedowns ( fastguns ) are only actiing in tension and nothing in compression which will also allow some movement , and are spring loaded . When you combine the movemnt in the frame , the frame mounts , the tiedowns and the camper it self it's usually enough . If you notice the folks that do more hardcore off-road travel loosen their tiedowns to allow for frame flex.
Another example would be a dump body on a one ton . The body is only attached by the rear hinges and the piston . The front has no tiedown , all it has in the front are guides to keep it from moving left to right when it's down on the frame .
If a camper were hard bolted down to a frame ALL the frame flex would have to be absorbed by the camper , not good.
I'm looking at building a wood-framed, plywood-decked minimalist flatbed. I will not bolt the tub directly to the bed. I'll look into some type of frame attachment tiedown if I can't make my current Happijacks work.
Thanks all for the discussion,
Mike
DiscoChicken wrote: I've thought of this idea too. A flat bed raises the base of a tc above the wheel well, thus making it too high IMO. Resting the tc on the frame OR building a flat bed on the frame with wheel wells is the best of both worlds.
That is a well thought out setup but the camper is still mounted higher then it would be in a pickup bed and the wheelwells extending above the deck still limit the width of the TC that can be used. It would be a great platform to build a custom camper on though.
I'm looking closely at that pic and I don't see where the deck is any higher than a normal pickup bed floor. There are cross members under the pickup bed floor that space it above the frame on any truck, plus the height of the bed floor corrugations. I think that deck is right about the same height.
The wheel wells appear to be a little shorter. Shouldn't be a problem, since most pickup bed wheel wells are unnecessarily high, considering how much space there is from top of the tire to inside top of the wheel well, especially on a 4wd 3/4-ton or 1-ton.
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