PocketShip.net

I know you are supposed to "drill, fill, drill" when putting a screw or bolt through plywood, i.e. the keel/centerboard pivot point. I filled with thickened epoxy and drilled a smaller hole through the epoxy. But what about all the attachment points for blocks, eyebolts, etc on deck and in other places? Are these ALL supposed to be drilled out, lined with epoxy, and redrilled? I believe some can be simply lined with marine-grade silicon calk, exemplified in the plans for the mast sail track. So my understanding is that I have three choices for EVERY hole in the topsides (please correct me if I am wrong):

1. Drill out large and fill with thickened epoxy.
2. Drill out to finished size, pour in a drop of unthickened epoxy, and then screw in the screw (like the eyebolt for the rudder in the plans)
3. Pre-drill, drop in some silicon calk, then screw in the screw.

Obviously #3 is the easiest and my preferred option, except for high-stress places like the tabernacle bolts and pivot points. For those, I guess I can just line the hole with unthickened epoxy to protect the wood and then put the bolt in.

Please reply if my understanding is incorrect.

Craig

for rigging attachments such as blocks, eye straps, cleats, etc. silicon calk in each pre drilled screw or bolt hole is the way to go. I like to see just a little sqweeze out. I pre drilled the mast and bowsprit tabernacle bolts then filled with thickened epoxy, then re drilled with correct diameter.

Herb

Thanks, that's the confirmation I need! Don't want to have any water problems...

Graig,
Silicone is not the best material for this application. On a boat the only use for silicone is bedding plastic that is otherwise damaged by other caulks. The reason for this is that silicone is a contaminant. It is very hard to remove if you ever need or want to repair/modify anything in that location. Silicone does not stick to other materials very well and nothing sticks to silicone. Cured silicone can only be removed by sanding with rough sandpaper, no solvent removes it. Primer/paint/epoxy do not adhere to a surface that has the slightest silicone contamination. Boatlife and Sika caulks are better for your application.

Hmmm, 3wtk, that is an excellent point about silicon and future repairs, repainting, etc. I will investigate the other products you mentioned as an alternative. For large holes (bowsprit, mast pivot, etc) pre-drilling and filling with thickened epoxy is fine, but for small holes I think it would be really hard and time-consuming to put a few drops of unthickened epoxy in each hole when inserting a screw. A calk-like product is much nicer. Thanks for the suggestion.

How about 5200 3M product for the small screws? http://solutions.3m.com/wps/portal/3M/en_US/Adhesives/Tapes/Products/~/3M-Marine-Adhesive-Sealant-5200?N=5510818+3294314620+3294314622&rt=rud I am always a fan of 3m products and I think I read somewhere it was being used in this application.

John,
3M 5200 is also a good choice. This product is at much an adhesive as a caulk and therefore seldom used when items may need removal (like deck hardware). However in this application these properties would be an advantage.