Stern Tube Flange to Hull Gap Filler?

cas206

.
May 15, 2012
24
Cal 27-3 Solomons
I pulled the bronze stern tube from my hull in order to make replacing the cutlass bearing easier. The cutlass bearing was extremely worn and I was getting lots of vibration. Age of whatever the sealant was and vibration made pulling the tube fairly easy.

The shaft does not exit the hull at a 90 degree angle. There is an inverted "V" shaped gap between the forward sloping keel wall and the bronze tube mounting flange. This was filled using some sort of pinkish colored filler that was rounded then covered with a thin layer of fiberglass. I immediately noticed that this putty was full of cracks. Digging at it, pebble sized junks were just falling out. Again it appears age and vibration had done it's damage. I have since removed most of the old putty.

Now I'm not sure how to go about repairing it. I attempted to keep most of the fiberglass skin intact. My plan was to use it as a form and fill in the space with epoxy putty. However, it has become apparent that I can't get down to clean glass without using a grinder. I can't reach the hull surface with the grinder without cutting out the remnants of the fiberglass skin (destroying my form).

I think I've pretty much decided to grind the whole mess (left over putty and skin) down to the hull. But then I've got to come up with a way to make a temporary form to hold the epoxy putty while it hardens. Another idea I'm toying with would be to epoxy a block of wood to the hull, shape it, then cover with fiberglass cloth.
Any ideas? Suggestions?
 
Sep 15, 2009
6,244
S2 9.2a Fairhope Al
I pulled the bronze stern tube from my hull in order to make replacing the cutlass bearing easier. The cutlass bearing was extremely worn and I was getting lots of vibration. Age of whatever the sealant was and vibration made pulling the tube fairly easy.

The shaft does not exit the hull at a 90 degree angle. There is an inverted "V" shaped gap between the forward sloping keel wall and the bronze tube mounting flange. This was filled using some sort of pinkish colored filler that was rounded then covered with a thin layer of fiberglass. I immediately noticed that this putty was full of cracks. Digging at it, pebble sized junks were just falling out. Again it appears age and vibration had done it's damage. I have since removed most of the old putty.

Now I'm not sure how to go about repairing it. I attempted to keep most of the fiberglass skin intact. My plan was to use it as a form and fill in the space with epoxy putty. However, it has become apparent that I can't get down to clean glass without using a grinder. I can't reach the hull surface with the grinder without cutting out the remnants of the fiberglass skin (destroying my form).

I think I've pretty much decided to grind the whole mess (left over putty and skin) down to the hull. But then I've got to come up with a way to make a temporary form to hold the epoxy putty while it hardens. Another idea I'm toying with would be to epoxy a block of wood to the hull, shape it, then cover with fiberglass cloth.
Any ideas? Suggestions?
make a fiberglass mold instead of a wooden plug then use it to get your shape back the way you want it to be and you may want to use west system SIX-10 as opposed to putty .....

just some thoughts

regards

woody
 

cas206

.
May 15, 2012
24
Cal 27-3 Solomons
I'll try to get pics this weekend. It's dark when I get off work.

Isn't Six-10 just West Epoxy with one of the adhesive fillers already mixed in? I already have some resin/hardener and several different cans of filler to make up an epoxy based putty.
 
Oct 17, 2011
2,809
Ericson 29 Southport..
More or less, sir. It's just an 'easier' product to use, epoxy = epoxy.

And from my experience, if you pile enough 406 silica in it, it will stay. May sag a little, but the important part will stay. I hate epoxy overhead, because like a lot of people end up eating half of it, but after everything under the sun tried, I have the best luck out of plain ol' duct tape. The epoxy will not stick to the glue side of the tape. And the forms people use are not generally like hull casting molds, what with gelcoated finished products coming smooth out of them. It will have to be sanded anyway, so perfection on the molding turns out to be a waste of time.
 
Jan 27, 2008
3,092
ODay 35 Beaufort, NC
, I have the best luck out of plain ol' duct tape. The epoxy will not stick to the glue side of the tape. .
That's a really good trick of the trade Chris, thanks for that. I have always used saran wrap to hold the epoxy in place with tape over that, using the tape directly makes it a lot easier.