I've just resumed work on converting my Rustler 31 and am about to start building the mast step, having completed the partners last year. I made the partners for use with softwood wedges but I'm now considering PMC-790 as an alternative.

David Tyler mentioned in a related topic that the partners need at least 100mm depth for the urethane to spread the load to the mast. My partners are deep enough and have the necessary taper but the gap between partners (270mm internal dia) and mast (222mm dia) will take about 1.7 litres of urethane to fill....pricey! I can easily build up the partners to reduce the diameter but what gap should I aim for, 10mm all round for example?

Does the mast step also need 100mm depth? What should the gap between hole and mast be? I'm building the step from stacked plywood/epoxy/glass and there will be a decent taper to avoid jamming.