Replacement Crank Mechanism for Skamper Pop Up

Last week my youngest child decided to crank the lifting mechanism backwards while the top was in the down position until the cable snapped at the crank. I thought that if a child can break it then it needed to be replaced. I took a closer look and the whole front area of the trailer needs some work. The cranking mechanism was being held on with one bolt and the handle was welded together and bent. I am not sure if it was original but it needed help. I am not really a welder but I do have a back ground in machining and metal work, so I took a machinist's approach to replacing the crank mechanism.

First things first, all of the old metal brackets needed to be removed. Somehow the previous owner bent the propane and crank brackets. They were welded on so I cut the welds off with my cut off wheel to get them out of the way. I purchased my replacement crank mechanism at Harbor Freight with a 20% off coupon for $17.00. Next I located a piece of 3/8" thick 6061-T6 aluminum bar stock to use as my new bracket. I laid the aluminum on top of the frame and started laying out the position of everything. I got everything "eyeball aligned" so that the crank shaft lined up to the crank clearance hole in the frame. I sharpie marked the locations on the aluminum plate of the new crank and also the angles where it connects to the frame. The angles ended up being 22.5 degrees which was an easy setting on my compound miter saw. Yes you can cut aluminum with your carbide tipped wood blades on your compound miter saw. I only cut aluminum on my compound miter saw or jig saw and never on the table saw. I prefer the miter saw because of the stationary back fence and the fact that the saw blade is turning away from you forcing the metal against the fence. Always cut slow and use cutting fluid (WD40 works). I then transferred hole locations from the crank to the plate and drilled and tapped those holes. I also drilled mounting holes on the outside edges of the plate and then brought everything over to the trailer frame to locate the position. Once I got everything lined up I matched drilled the holes into the frame. Only leave a dimple in your drill holes so you can get everything out of the way so you can do some real drilling without losing location. I only drilled through the top part of the steel channel which was around .125" thick. I tapped those holes too but then followed the screws with Nylok nuts on the bottom for extra strength.

Next was making a new shaft to go from the new crank output shaft to a place outside of the frame. The previous owner rigged a welded tube that got bent. I used a solid piece of 3/4" 1018 steel (cold rolled steel, nothing fancy). I drilled a .450" hole in one end on my drill press and drilled cross holes and tapped them. The other end was also drilled and tapped for a retaining hole for the new handle. This end also needed to be tuned or ground down. I do not have a lathe but I do have a bench grinder that I carefully ground the tip of the OD down to .470". I then had to grind a .330" flat on both sides (.330" being the total distance of the flats). This fit the new keyed end of the crank handle. Everything fit well and it is better than new. Check out the pictures below.

Pop Up Lifting Crank Mechanism Before

Skamper Pop Up Old Ratcheting Crank

New Harbor Freight Crank

New Skamper Pop Up Crank Mechanism

Solid Steel Shaft Connected with Double Screws

New Lifting Crank for my Pop Up