Boat/yacht leg fitting

[Freddie100]

looking for some advice please, I m about to fit a set of legs to my coastal cruiser, I plan to use a 18mm H/T single bolt through the hull just below the deck level.
I plan to fit a 460 x 150 x 25mm oak block to the inside of the hull to take the through bolt, however I am undecided to fit a same size oak block of wood on the outside to take the fitting bolt. I realize this will increase the bolt length and also the strain on the bolt, or to fit a steel plate about the size of 150mm square on the outside fixed through to the block inside, I have read many write-up and forums on this subject but could do with a bit of advise on the subject
also how much should the legs splay out from the vertical for the best stability.

Freddie

[psk125]

It would seem that a shorter bolt would have less tendency to get bent by the forces and leverage involved. Spreading out the load to the hull with an oak board is a good idea, but backing plates -inside and out - will also need to be a part of the equation, to avoid the bolts simply pulling through the wood. Angling the crutches or legs outboard would seem to make the problem of leverage on the bolts much worse. When grounding out, the boat is theoretically supposed to be supported by the keel structure, with the legs simply keeping the boat from tipping over. It the legs are splayed out, any force on them will tend to twist the fulcrum (the bolt) with the full length of the leg acting as a lever with the weight of the boat on it. Not a pleasant scenario. Hasn’t this been covered in the write-ups and forums you researched? What kind of boat are you planning to do this with? The fact that you need legs indicates that it’s not a flat-bottomed boat that would ground out fine without them. What is the draft? Where are you sailing? Unless you can pretty much guarantee near calm conditions for both grounding out and UN-grounding out, the process is not likely to leave your keel- and the keel-hull joint - undamaged.