Doug (and others),
There are as many ways to remove a trailer, so as to remove keels, as there are trailers. Rather than give a definitive course of action, please be guided by the good points made in several articles. Stating the obvious I appreciate, but the boat weighs in excess of two tones; you can’t be too careful. If it all goes pear shaped, not only could it kill you, but at the very least it would seriously spoil your day. Some questions…………..
Can the boat be lifted from above, in slings, using chain blocks slung from strong rafters/beams?
Can you get side access with a suitable fork lift truck?
Will the use of beer barrels provide a safe and secure platform at ‘each corner’?
Can you get to both sides of the boat and can you perform the lifting operation without EVER going underneath the boat?
Can you ensure that the lifting operation is done in small incremental lifts, one end at a time, such that the boat remains more-or-less level fore and aft – and more crucially – side to side?
Can you ensure that there is a back up supports, so that if the (for instance) beer barrel slips, the boat will only drop a very small limited distance?
Are the scantlings up to the job – i.e. jacks, beams, supports etc? Remember the two tons?
Once the boat is up to the necessary height, build really good sturdy pillars to support the weight of the boat. You are going to be working on the keels, inside and up on top of the boat and the last thing you need is for the boat to be wobbling and teetering about whilst your up there working. A1’s pillars were built beneath the two main bulkheads at either end of the keel boxes and were offcuts of oak, approx 15 x 15 cms in section and 60 cms long, stacked in pairs with each layer at right angles until the height had been achieved. There were four pillars, with a very stout beam between each pair. Don’t forget wedge pieces between the beams and the hull so the boat remains upright. I also placed two sturdy posts, with suitable wedges, beneath each end of the boat, one propping up the skeg and the other beneath the fore foot. Beer barrels won’t cut it.
As to height –
a) For general maintenance, the higher off the ground the better. Removing paint/anti-foul from underneath is not the best job in the world – lying on your back makes it even worse. A1 was approx 75 cms off the ground; I modified one of these plastic chairs by removing the legs and using the bucket seat and back. With my legs stuck out in front, I had a seat to sit on (albeit just about on the ground) but importantly, a rest to support my back.
b) For removal of trailer – make sure there is adequate clearance, particularly the after trailer chocks. Don’t be tempted to think “that looks all right, I’ll give it a go.” It just needs one snagging and potentially the whole edifice comes tumbling down. Wouldn’t be the first time……………
c) For keel removal, a metre ought to be fine, probably less
d) If you’ve jacked the boat up to give good clearance for trailer removal, then the boat will be high enough for keel removal and general maintenance.
A final thought – my experience is that one knowledgeable assistant is excellent. More than that and you end up with the old conundrum of too many chiefs etc……………….
Good luck – take it slowly. I don’t think we’ve lost anyone yet……………..