[gregbradley]

I have built a roll off roof observatory. The roof does not roll off very well.

I used 100mm C purlin on its side as the track and 75mm wheels on an M10 axle bolted through 100x 40mm 3mm steel section.

There is very little clearance for the wheel inside the purlin and I think that is the problem.

I am thinking I will lay the purlin in its back and see if that works better.

Suggestions?

Greg.