Hull Repair Material

[SailorDave5050]

Installing proper seacocks in the boat, with countersunk screws through the hull. Now...what do I fill those countersink areas in with? Boat is all fibreglass. I have liquid fibreglass and cloth but that is messy and runny. Is there something like auto bodyfill that is more like a paste that is good for this type of thing? I'd also like to use the same stuff to level off the inner hull before installing the seacock backing plate. Any suggestions welcomed!! Thanks!!

 

[finding41]

Butyl tape on the inside of the hull and in the holes before you insert the screws/bolts. As for filling the holes... Why make them so deep? I would only make them as deep as to let the head of the fastener come flush with the outside of the hull.
Have you already made the counter sink holes too deep? Maybe put a piece of tape inside or out depending on ware the hole is and fill it back up with fiberglass resin and drill new ones when that hardens.
See MainSails thread on bed it with butyl.

 

[Bob McL]

I think he is talking about getting rid of the through-hole. If so, I used a product called RestoGRIP put out by POR15 folks. It is fiber filled epoxy and thick. Someone on here the other day showed a Bondo product product (not the common body filler). It was also a fiber filled epoxy for auto and marine applications. You can also fill epoxy resin with micro balloons as a thickener. But if bridging a wider area than a screw hole, you should use a fiberglass material with a weave for strength. And properly prep the area for the repair - taper the sides and rough up the area for better grip.

 

[Bill Murray]

good discussions can be found by searching.... here is one http://forums.hunter.sailboatowners.com/showthread.php?p=788135&highlight=seacock replace

 

[Bill Murray]

another ....http://www.pbase.com/mainecruising/replacing_thruhulls

 

[sailaway78]

If you just need

If you just need to fill a shallow depression where the screw head is a little low, I would think Marine Tex would do the job nicely. You can get it in fairly small amounts, is an epoxy and not a polyester, and is comparable to Bondo, in the way it works. Although slower to set.

 

[Winkfish]

If you just need to fill a shallow depression where the screw head is a little low, I would think Marine Tex would do the job nicely. You can get it in fairly small amounts, is an epoxy and not a polyester, and is comparable to Bondo, in the way it works. Although slower to set.

I second Marine Tex. I've used it a lot, above and below water lines. Great stuff.

 

[SailorDave5050]

Thanks for all the great info. Seacocks are going in the same locations where the old valves came out. No seacocks before...just thru-hulls and ball valves with rotted off handles. The countersinks aren't drilled too deep. They are just deep enough to recess the flat head screws maybe 1/8" below the surface. Now, I will fill those holes, sand smooth and paint. The Marine Tex looks perfect. I see that I can get it locally and should also work great for the backing blocks I have made for the flanged seacocks. Things are coming together. Sailing soon!!!! Thanks again!!

 

[mitiempo]

I would not use butyl under the waterline, only on deck. A better choice is Sika 291 or 3M 4200.

 

[Merlin Clark]

and bed all fixtures from the outside and not inside the boat.