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Timber repair advice


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Ok, had a oopsie with the pulpit and it has torn the screws out of the timber deck/glass hull join. The stanchion pads are bolted on the inboard side and wood screws on the outboard side. I can't go to longer screws and not sure I want to go to thicker ones (assuming I can get any here). What is the best way to repair the screw holes?

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Gidday Peter. The conventional wisdom that I've observed over the years is that its best to epoxy new wood into the holes and re drill.

How you do that is where it becomes interesting. If you use dowels, you're introducing grain which is orientated the wrong way ( North south)and risk wicking water deep into the screw holes. So its probably best to rather cut bungs or stack bungs , epoxy in and redrill .. that way you get the grain crossing east west as it were and have less risk of the wick effect.Some people I know don't worry about that and use toothpicks packed tight down into the hole and epoxy,but another idea which appeals to me is to use bamboo stakes( kebab etc )the same way, the logic being its hard and stringy wood and adds a toughness back to the screw threads.

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Some say yes, But we're yachties aren't we.. we like redundancy.

Besides .. remember all those farr 38 stem fittings with bolts bedded into epoxy.. I don't trust it for thread joints regardless of what the book says.

 

I'm also thinking about it because I've got some staunchions to rebed. My current thinking is to redrill the blind holes for clean timber and known length. Then to cut some bamboo stake/kebab/ toothpicks shorter than the hole and pack them loosely into epoxy thickened with fibres( glue mix) so that there's a epoxy 'cap' to each hole. Then redrill and bed with sika as normal.

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The hardware stores sell drillbits with a countersink cutter attached that can drill a 10? mm hole. You then buy a freaky little cutter that cuts bungs the correct size for the countersink in scrap timber. They come in a pair and various sizes to suit different size screws. The grain is then oriented the correct way in the bung.

I've used one to mount handrails on the cabintop that have exposed wood.

I use the drillbit with countersink all the time for screwing stuff together. One operation rather than countersinking after drilling.

 

If you just get a drillbit the size of the bung instead of using the countersink bit, you won't have the screwhole.

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Pete, drive a piece of wood dowel or even just a piece of off cut whittled to the ruff size into the hole. Hammer it home and trim it flush. Drill a pilot hole where you want the screw to go. Now dribble a little Evadure (or thinned down epoxy which is just as good) into the new wood and the pilot hole. Keep dribbling till it is saturated. Now place the fitting in place and screw home. The expansion of the screw forces the plug out against the hole and the Epoxy seals the grain and glues it in place as well. It will never tear out under the normal loads. This technique works for fibreglass holes also and I have always found that the screws hold better into the timber plug than the glass in it's own.

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All good advice thanks, I was worried about the end grain thing as there is quite a lot of load on the pulpit when climbing on & off the boat when we're in the marina and I didn't think it would be strong enough. Looks like cross grain plugs & epoxy. Now I just have to fit a plug cutter in Fiji :?

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No end grain is fine Pete. It in fact has more holding power. Screw threads bit into the grain better that way. Cross grain ends up coming out with the threads. Just as long as you seal it with epoxy.

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Had to fill all the old stantion holes so we drilled the old holes out till we had clean undamaged timber then used epoxy glue and dowel, sunk the dowel in so it was below the surface of the deck by a small amount and filled the rest with an epoxy glue/faring mix, allowed that to cure well then sanded it smooth and painted.

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Get out your knife and whittle up a few plugs. Shouldn't be an issue for a crusty old sea dog like yourself Pete. Just watch out no embers fall out of your whale bone scrimshaw covered pipe and burn the boat to the waterline though :lol: :lol:

 

Once you've done that can you whip us up some of that fancy newfangled Manila rope stuff. I think TNZ may need some now the drug pusher lost his silverware :)

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