Loose flotation blocks in Minifish

[Tom L.]

I have a 1977 Minifish, and I think the foam flotation blocks have come loose in the forward part of the hull. I can hear something soft (not metallic) thumping around when I tilt the boat back and forth, and the deck seems to flex more than usual when I press on it.

This raises a few questions:

(1) Is it feasible to re-attach the blocks through an inspection port, without peeling apart the hull? If so, are there instructions available, or at least a recommended type of adhesive?

(2) Does anyone know whether the blocks are in the same positions in the Minifish as the Sunfish, as shown in the two links below?

(3) Where would be a good location to put an inspection port for this job?

http://kb.sunfishforum.com/images/Flotation_Blocks.pdf

Sunfish Construction

 

[tag]

1. Yes, but it is difficult. Use 2-part expanding foam. I did it for my Sunfish and blogged about it here: foam block reset
2. not sure, but I’d guess the foam block layout is similar.
3. On the deck either just behind or just forward of the splash guard maybe? I’d keep it away from the mast step. On my Minifish, I put the port off to the side of the daggerboard slot.

 

[tag]

 

[signal charlie]

Lordy, forgot how small that deck is behind the coaming. You'll find good answers here!

 

[L&VW]

3. On the deck either just behind or just forward of the splash guard maybe? I’d keep it away from the mast step. On my Minifish, I put the port off to the side of the daggerboard slot.

Right-handers consider the other side!

 

[signal charlie]

(1) Yes. AS far as I know the hulls with the rolled deck edge never get peeled apart.
-Instructions will vary based on which location you decide to put the hull. I am starting to come around to the ideas, presented here on the forum, of skipping the inspection port and instead 1) cutting an access hole and fiberglassing the cutout fiberglass piece back in place and/or 2) accessing the interior from bottom.
-Recommended adhesives for block attachment are 2 part, 2 pound marine grade flotation foams. We have used TotalBoat Flotation Foam and Fibreglast 2 lb Polyurethane Mix and Pour Foam. These foams are closed cell structure and do not react with gas, oil or water. Don't tell anyone we said anything but Great Stuff works for small fixes, but you need to make sure it doesn't sit immersed in water for extended periods because it is not closed cell, it will become a sponge. Also not sure about the flotation characteristics of great stuff, keep in mind the expanding foam inside the Mini is used both as an adhesive and as flotation.

(2) Does anyone know whether the blocks are in the same positions in the Minifish as the Sunfish, as shown in the two links below? We have not seen photos on internal blocks on the Mini, and as the Owner of the Yahoo and io Sunfish_Sailor Groups, we have been through 10s of thousands of photos of Fish. If you live in a dewy cool spot that warms up in the day you might be able to catch the dew witness marks over the cooler block areas, as the rest of the deck warms faster.

(3) Which side or area feels soft, in comparison to the other side?

 

[signal charlie]

Inspection ports are nice, esp if they are close to the daggerboard trunk, which often needs attention. Also a good spot for a dry bag insert, and over the low spot in the keel = good sponge out spot.

From another post, here is another option for interior access: