Skin fitting

[mpe]

Hello, I am wondering if anyone has advice on removing a 2 inch bronze skin fitting and filling the hole on the waterline of my GRP Colvic Atlanta, which I cannot have lifted out of the water.

I can heel the boat to get the fitting out of the water but will need to seal the hole from the outside while I epoxy the hole from the inside.

Any ingenious ideas?

 

[Deleted member 36384]

I would fair a section of ply or wood to the curve of the hull at the sea cock. Make the wood patch a good bit larger than the hole. After you have removed the sea cock fair the hole from the inside as the instructions in the link below. Clean up the dust. Place a small section of polythene over the hole on the outside of the hull, say overlapping by a centimetre. Using a marine adhesive / sealant apply a wide bead around outside of the face of the faired wood. Stick the faired wood over the hole from the outside of course.

Once the marine adhesive / sealant has cured take the heel off your yacht and proceed to repair the inside of the hole as noted in the link below.

http://www.westsystem.com/ss/use-guides/ Scroll down and click on 002-550 Fiberglass Boat Repair & Maintenance. The instructions for making good existing holes are in this document. The instructions are good for other GRP products, not just the West System.

 

[fisherman]

Plastic and sandbag, or screw on ply inside, fill the hole outside, then grind back feather edges inside and patch, then feather the outside and patch/gel/finish. Or just knock a taper hardwood plug in the fitting and leave it.

 

[VicS]

Hello, I am wondering if anyone has advice on removing a 2 inch bronze skin fitting and filling the hole on the waterline of my GRP Colvic Atlanta, which I cannot have lifted out of the water.

I can heel the boat to get the fitting out of the water but will need to seal the hole from the outside while I epoxy the hole from the inside.

Any ingenious ideas?

The correct way of repairing such a hole is to grind a 1:12 taper to the edge of the hole from the outside. ( that means if the hull is 1/2" thick you are grinding back 6" allround). Section 4 of Old Boots' link

then lay in circles of glass mat or fabric starting with one equal to the diameter of the ground area followed by progressively smaller ones as the repair progresses. no backing for the first layer should be necessary if it is allowed to cure before proceeding but something coated in a releae agent may help if it can be wedged in position inside

However I have to do a similar repair to you. My boat is out of the water. I am thinking of fixing a piece of thin sheet metal ( old aluminium drinks can) coated with a release agent over the outside of the hole with the strongest self adhesive tape I can find and the laying up and covering from the inside.

I will taper the hole, so that it is a larger diameter on the outside, first.

I will use epoxy to avoid having to gelcoat the repair and because it wil adhere to the existing better than polyester

Peel ply might be a better choice than a beer can

 

[lw395]

Maybe laminate a temporary patch to approximately fit the curve of the hull.
Heel boat, remove skin fitting, fix patch with polyurethane sealant.
Then working from inside, make good the hull.
At a later date, remove the patch and fair the outside.

 

[GrahamM376]

Main problem is that the area needs to be thoroughly dry before patching. Can't you just screw a blanking cap onto the fitting until you can haul out to do the job properly? The surrounding GRP needs scarfing back inside and out.

 

[prv]

Can't you just screw a blanking cap onto the fitting until you can haul out to do the job properly?

+1

It seems to me that the fibreglassing is unlikely to be done properly under adverse conditions. It might be good enough, but if it was me I'd always wonder - especially at night, miles from land, in a bit of a sea...

Better to temporarily seal the fitting until you can fill the hole properly, including grinding both sides. I can't imagine using an angle grinder inches above the waterline of a floating boat.

Pete

 

[lw395]

Main problem is that the area needs to be thoroughly dry before patching. Can't you just screw a blanking cap onto the fitting until you can haul out to do the job properly? The surrounding GRP needs scarfing back inside and out.

It's not really necessary to scarf back the GRP on both sides, if the repair is allowed to be thicker than the rest of the hull.

The inside will need to be dry before attacking the permanent repair, but the temporary patch could be applied with something moisture tolerant perhaps?

 

[viago]

Any ingenious ideas?

leave it in and go to the pub.

 

[Modulation]

+1

It seems to me that the fibreglassing is unlikely to be done properly under adverse conditions. It might be good enough, but if it was me I'd always wonder - especially at night, miles from land, in a bit of a sea...

Better to temporarily seal the fitting until you can fill the hole properly, including grinding both sides. I can't imagine using an angle grinder inches above the waterline of a floating boat.

Pete

+2 having had to remove one recently when I had the boat hauled out. I certainly wouldn't want to do even that in adverse conditions as so much can go not to plan.

 

[PCUK]

You can do the same thing as Vic suggests from the inside. First cut your ply to fit on the outside and then cover it with well waxed (non silicone) decorative laminate (Formica). Grind out the crater on the inside and then gel coat the laminate up to the edge of the hole. Then build up with mat and resin as per Vics suggestion.