OK...

Posted By: Sam Hunter, '93 Mac26S, Atlanta & Pensacola
Date: 11/12/09 3:48p.m.

Report: outside forum guidelines

In Response To: Sam can you elaborate........ (link) (pic) (Sumner & Ruth -- Mac 26S -- Blanding, UT)

At least in the 93's, there are access plates to the ballast tank at the pivot bolt, one under the sink, the other under a small cap on the cabin sole next to the sink. I had to remove the plates when I replaced my broken centerboard. I figured that, while I had everything opened up, I'd add a bit of hard ballast. (The new "M" models have a couple hundred pounds added.) The location is right under those access holes, spread foreward and aft a bit. What I did was to drill and tap several (6 per side IIRC) 1/4 holes into the ballast tank from the outside, 2-3 from the centerboard case slot, and 3-4 from the bottom up. This gave me bolts that were horizontal (from the slot) and vertical (from the bottom), to ENSURE the concrete would never move. I was re-doing the bottom anyway, so it was no problem at all to epoxy the bolts into place. From the inside, I added one or more nuts to each bolt, for better holding. Then, I mixed up an 80-pound bag of concrete and trowelled it into the holes, spreading it fore and aft and to the sides a bit. I did tape over the pivot bolt and nut, and did ensure there was no concrete blocking future access to it. For clarity, the tank is separated by the slot down near the bottom of the ballast tank, so it is like putting in two separate chunks of concrete. I could have used lead and epoxy, but that would have cost Many Times the $7-8 bucks I spent on concrete and bolts. This does cause some water to remain in the ballast tank, forward of the concrete "blobs", but it seems to mostly drain out in the stop and go of traffic. Seems to work great! FWIW, it is quite a PITA to get in under the sink and work on that side, and BOTH access plates are a PITA to remove, so it is not a project for the faint of heart. Also, I ended up making my own replacement plates from 1/4 ply and epoxy as the factory ones are just too cheaply constructed for re-use. Hope this helps. If I am only as clear as mud, feel free to ask questions and I'll try to give a better explanation.