I’ve finally got my launch wheels sorted. Having collapsed on me once and now looking ready to give up again, I decided it was time to get them fixed. As
@harrison pointed out, the majority of them fail for two reasons, usually combined, The first is that the fixings are too close together to resist the torque inflicted on them when traversing anything but a smooth surface with a small motor. The second problem which exacerbates the first is the need for the legs to negotiate projecting trim tabs of one sort or another thus resulting in even more unhelpful leverage.
Mine are the slightly cranked variety which engage with spring loaded pins in either wheel-up or wheel-down mode. They were originally fitted using 2”x2’” hardwood spacer blocks in order to clear the trim webs at the base of the transom. Unfortunately these twisted in their holes and collapsed on first use and so heavier bolts were tried but this only succeeded in splitting the blocks and pulling the washers on the other side into the transom.
It needed re-thinking.
- Hardwood blocks have split
First of all I decided to use aluminium rather than wood. I also reduced the spacing down to 1 1/2”. I would have to use the original holes in the transom which had endured some trauma due to the earlier failure so decided to extend the spacer vertically and add another bolt. With three M10 stainless bolts in snug holes though a solid aluminium spacer, I would now be able to get it very tight except that the washers and nuts on the inside would damage the transom. This is why I added the 4mm stainless plate on the inside - and because the off-cut I had was just over 200mm long, I was able to add yet another bolt which doubles up as a tow eye. Had this been a virgin site I would have probably gone for a more elegant solution but as a damage limitation exercise I’m quite pleased with the result.
I also replaced the wheels with puncture proof versions, the split pins with R clips and added pull wires to the spring pins to make releasing them easier from above.
Everything is fully sealed with black Sikaflex - including my hands, and tools. The tools clean up with thinners but I think I'll need a skin graft to get it off my hands.
