I have a Knaus Skywave Motor Home. I started with a pair of yellow ramps as sold by BCF etc but found I often had to hold the vehicle on the ramps with the handbrake, which then creaked and groaned as we moved about inside. Also using chocks on the ramps is a bit dangerous for my wife if she is not quick enough!! I found the Andersen chocks (U.S. manufacture) online and ordered a pair. Perhaps this should have been obvious to me but they are not suitable for the drive wheels of a motor home as if there is any sort of moisture on the tyres or you accelerate a bit quickly the chock is pulled under the spinning wheel and can be spun out the other side. They are absolutely suitable for towed wheels as on caravans and the non-drive wheels of motor homes. Once on the chocks the wheels sit in a depression and obviate the need for the vehicle to be held on the hand brake, although it is still applied for safety.
The major force on the chocks will be vertical, the horizontal force generated by the spinning wheels will be quite small.
How about:
Drilling a hole in each of the two channels which run the length of the chock
Locate the holes at the low end of the chock right at the beginning of the channel
Place chock on ground and hammer a 8mm steel tent peg into each hole ensuring its turned end sits flat on the chock (you may need to saw a few tent pegs in half) in such a manner that it will not cause tyre damage.
This will stop the chock being moved by the driving wheels.
__________________
"I beseech you in the bowels of Christ think it possible you may be mistaken"
Oliver Cromwell, 3rd August 1650 - in a letter to the General Assembly of the Kirk of Scotland
Perhaps I should have explained that these levellers are not like the 'conventional' ramps. They are designed to raise the vehicle as the wheel travels over the ramp i.e. the ramps rise to either full or part height as desired. The chock is then placed under the raised portion. For a video go to: www.youtube.com/watch
However I can well understand why driven wheels would be an issue and they ought to make that clear in their advertising.
How about...
Drill a (say) 6mm hole in the high end of the chock, in the end plate not the ramp, and feed 500mm of rope through it. Make a couple of knots in the rope such that it cannot be pulled out of the chock.
Tie a small loop in the other end of the rope and using a strong tent peg tether the ramp to the ground.
The force of the driving will try to push the chock backwards but the rope will restrain it.
Well... that's my theory anyway but then... I am an electronics engineer rather than a mechanical one :)
Edit:
Thread the rope through a large metal washer or make a 40mm x 40mm steel plate with a hole to take the rope and locate this between the knot and the plastic moulding of the chock in order to spread the load.
-- Edited by Mike Harding on Wednesday 22nd of February 2017 12:47:35 PM
__________________
"I beseech you in the bowels of Christ think it possible you may be mistaken"
Oliver Cromwell, 3rd August 1650 - in a letter to the General Assembly of the Kirk of Scotland
I retained the 'conventional' ramps so I am able to mix and match to get the correct ramp under the required wheel. The beauty of the Andersen ramp is that once you have 'mounted' it, the wheel sits in a hollow and obviates the need for a firm handbrake hold.