The following day I set too with paint brush and wood preserver to coat all the cut ends of the block in an attempt to slow the cracking of the blocks due to them drying out.
I jacked up the trailer one side at a time and blocked it up such that the tyres were off the ground.
So far so good and the whole thing is really stable allowing me to work on moving the axle without fear of the whole thing collapsing on me as I work.
I decided to move the axle forward 100mm or 4″, an inch or so more than necessary and marked the spot on both sides where the axle should end up. Then it was a case of loosen the nuts on the u-bolts and wriggle the axle forward to the new position. I say wriggle but in practice it was hit it with a mallet as the axle is heavy!
After a dozen or so small moves the axle was in the correct place and I tightened up the nuts again, jacked the trailer up again and took out the blocks. Now for the acid test. I suspended my 350kg scales above the hitch and measured the weight.
Not pretty but it works well.
Not easy to see in the bright sunlight, but the tongue weight of the trailer and empty boat is 37.4kg. That is pretty close to being correct, not that I’ll be towing this trailer anywhere but if I have to do that, then the tongue weight is not far off the correct value.