For an M17, depends on your year. Or maybe varies from boat to boat in the early days? Mine is M17 #38, 1974, and there is no balsa core anywhere in the topsides mold layup that I am aware of or have so far discovered. And I've explored most all of it for one reason or another. Re-bedded most everything and added some jib furling guides & clamcleat, port side bow cleat, main halyard to cockpit cheek block & cam cleat. Had the window frames out at one point also. My cabin side decks, sides, & top are stiffened with glassed half-tubes underneath, running side to side, fore and aft of the shroud chainplates and mast step. Also several of same reinforcing the fore-deck between front of cabin and bow stem. Brilliant if you ask me - all glass, nothing to rot if a penetration lets water in, one layer, no core to cut and place, no chance of delamination/poor bond, etc. I am really glad I have this layup. Just means there's a few narrow strips of locations fore to aft where you wouldn't want to install any hardware above, because the bolt(s) would come thru where a stiffening half-tube is. Cockpit floor and locker hatch cores are foam, not balsa, on mine. Maybe it was that way until change of topsides mold, from flush hatch to raised? Don't know when that was. Just guessing. Jerry we may need the story from you on this... cheers, John On 9/16/21 6:39 PM, Dave Scobie wrote:
Andrei.
Almost all horizontal sections of the deck are balsa cored. Same for M15 and the Sage 15/SC/17. See my prior email that has links to my BLOG and details rebedding deck hardware.
As you are keeping the boat in-water did extended periods what antifouling are you using on the hull and centerboard?
:: Dave Scobie :: M6'8" #650 :: SV SWALLOW - sv-swallow.com :: former owner M17 #375 SWEET PEA - m17-375.com :: former owner M15 #288 SCRED - m15namedscred.wordpress.com <<-- new site!
On Thu, Sep 16, 2021, 6:32 PM Andrei via montgomery_boats < montgomery_boats@mailman.xmission.com> wrote:
Jerry, do you know if the cabin top where the hand rail attaches is solid glass or it is balsa core? If it were solid glass it would take some of the pressure off of doing this repair right away.
Andrei.
-- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com