Our quarterly foam forum
SteveI too am the proud owner of a Mac 22, except my pre-date yours by 8 years. As an antique - these boats show some wear - not the least of which appears on the foam blocks. My 22 has a large single block under the cockpit, end to end, from hull support to hull support (which by the way is where your Hull number is engraved - starboard side).Up front its a jumble of smaller blocks - likely twelve or so - about the size of a square basketball- loosely placed in the V berth cavity. You can get more floatation in that space (see below)My plan is to add floatation along the aft compartment between the hull supports and the curves hull wall as well as replacing the loose blocks in the V berth cavity. Being an odd shape - I originally thought of expansion foam. The great people on this forum pursuaded me NOT TO USE EXPANSION FOAM (for many reasons). The alternative that worked best for me was packing peanuts (careful not to get the corn starch ones - they dissolve) inside heavy duty garbage bags.Advantages:*CHEAP - ABOUT $30 FOR 14 CU FT BAG (2 bags is plenty)*CLEAN - NO SPRAYING, NO SPILLAGE, NO SOLVENT FOR CLEAN UP, NO ODOUR, NO VAPOURS*FORM TO ANY SHAPE HOLE*INSTALLATION IS NOT TEMPERATURE DEPENDANT*PEANUTS DO NOT EXPAND - FOAM CONTINUES TO EXPAND AS IT CURES AND COULD FORM A POCKET THAT FORCES EXPANDING FOAM TO BULGE THE HULL*EASY TO REMOVE FOR MAINTENANCE AND RE-INSTALL - DONT EVEN ATTEMPT TO REMOVE THE FOAM AFTER IT HAS BEEN INSTALLED*IF THEY GET WET, REMOVE, DRY AND RE-INSTALL*IF PLANS CHANGE - RIP THEM OUT IN 2 MINUTES*ONE MAN INSTALLATION JOB (THREE BEER TASK)*WIFE LOVES LEFT OVERS FOR CHRISTMAS PARCELSBest WishesRichard