What kind of Resin were 1980s Four Winns made of?

[CRJDriver]

I have a 1986 Four Winns Horizon 170. I am rebuilding some rot damage. Does anyone know what kind of resin the used back then? I am planning on using MAS epoxy to glass in new plywood to the old fiberglass and I am concerned about a good bond. Thanks!

 

[tpenfield]

Re: What kind of Resin were 1980s Four Winns made of?

Welcome to iBoats . . .

Most likely polyester resin on the FourWinns.

Lots of folks use polyester in their repairs/rebuilds. Vinyl ester may be better for bonding. . . I would not use epoxy for structural members . . .

 

[Bondo]

Re: What kind of Resin were 1980s Four Winns made of?

Ayuh,.... I dare say that 99.9% of all fiberglass boats built since WWII have been Polyester resin built..

'n yer usin' epoxy, so No worries, on a properly prepped surfaces...

 

[CRJDriver]

Re: What kind of Resin were 1980s Four Winns made of?

Welcome to iBoats . . .

Most likely polyester resin on the FourWinns.

Lots of folks use polyester in their repairs/rebuilds. Vinyl ester may be better for bonding. . . I would not use epoxy for structural members . . .

Just currious why not? I have no experience working with resin.


This is what I am repairing. I have cut out a doubler from 1/2 marine plywood to sandwich the rotted bulkhead. I then plan to glass it together.

Any and all advise will be considered.

 

[Woodonglass]

Re: What kind of Resin were 1980s Four Winns made of?

Have you core sampled the rest of the stringers and bulk heads. Looks to me like you have more issues than just that one bulkhead. Your boat is made from poly so why not just use polyester resin to do your repairs??

 

[CRJDriver]

Re: What kind of Resin were 1980s Four Winns made of?

I stuck my finger in the drain holes of the stringers at the stern. Three out of four felt good. The right side lower stringer felt like mush. Since then it has been in the garage drying out. I have access to a boro-scope. I was going to borrow it to look in those drain holes. I replaced some wood around the gas tank as well.

I know that at least that one of stringer needs work. My thought are to rebrace that bulkhead and put the replacement floor cut out back down and lightly glass it in. Then enjoy the boat until fall. At that time I would have the entire winter to pull the gas tank, and cut open the stringers. I think the problems are at the very back of the boat. The rest seems solid and dry.

 

[CRJDriver]

Re: What kind of Resin were 1980s Four Winns made of?

Well. This is what I accomplished today.



I build a bulkhead sister out of marine 1/2 ply and sandwiched the bad bulkhead with stainless through bolts. I coated it in Penatrating epoxy. I will then glass it to the side stringers with poly resin and 6" tape.

Any advise or critique is appreciated!

Also, will the poly resin bond to the wood that I treated with the penatrating epoxy? I plan to sand it lightly with 80 grit and then wipe down with acetone.

 

[Scott Danforth]

Re: What kind of Resin were 1980s Four Winns made of?

you have to remove the rotten wood and replace properly. sistering it is a bad band-aid.

Poly resin will not stick to epoxy.

penetrating epoxy is snake oil. doesnt really work.

use 24 grit or 36 grit.

Just my $0.02

 

[tpenfield]

Re: What kind of Resin were 1980s Four Winns made of?

Well. This is what I accomplished today.

View attachment 156891

I build a bulkhead sister out of marine 1/2 ply and sandwiched the bad bulkhead with stainless through bolts. I coated it in Penetrating epoxy. I will then glass it to the side stringers with poly resin and 6" tape.

Any advise or critique is appreciated!

Also, will the poly resin bond to the wood that I treated with the penetrating epoxy? I plan to sand it lightly with 80 grit and then wipe down with acetone.

My advice is that the rot has not been stopped in any way and will continue into the stringers, etc. The wood in that boat does not look so good, and I know things look more vivid in person versus photos. So, this might get you through the season, but it looks like an off season restoration is in your future (sorry).

 

[CRJDriver]

Re: What kind of Resin were 1980s Four Winns made of?

I agree. I am going to have to do a major gut and rebuild. I want to make the boat safe and use it for the summer. I have a heated garage to tear it apart this winter.

Does anyone know if polyester resin will bond to the West Marine penatrating epoxy well? I need to seal up the plywood deck that I coated with the penatrating epoxy, but if I am going to have to pull it up this winter I don't want to epoxy glass it in. (expensive and harder to rip out).