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I have a small 5 meter sailing dinghy called a Still 525. 

My mast deck plate got damaged and has been sent for repair. It is attached to the deck with 4 screws (see photo). I was wondering whether I should do something to fortify the screw holes whilst the deck plate is being repaired. This way when I reinstall the deck plate it will be "stronger than ever". Not sure what I should do exactly. Should I just pour some epoxy in the holes?  Any suggestions?

I do not have access to the underside of the deck. IMG_20210905_125616.thumb.jpg.e71fa35abb6ac16532e1bf1f9474a8d9.jpg

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Could you tell us what those screw holes are going into?

Is it just a lump of solid glass laminate? If so how thick?

Is it a cored material? If so what's the core and how think is the outer skin?

Can you get to the other side?

Edit. Sorry, I see that you wrote you can't access the other side.

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Attached a photo of what is below. It's all fiberglass underneath. There is also some sort of strut to strengthen the deck. However I believe this is more related to supporting the mast. The old screws are 2.5cm long and 5mm wide. 

IMG_20210905_125629.jpg

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2 hours ago, bluefightingcat said:

I was wondering whether I should do something to fortify the screw holes whilst the deck plate is being repaired.

Point of interest, were they lose after the damage? If they weren't there may be nothing in need of fixing.
It's also the mast step, most force is compressive and not carried by the screws so back to the above, is there any actual need?

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2 hours ago, bluefightingcat said:

I have a small 5 meter sailing dinghy called a Still 525. 

My mast deck plate got damaged and has been sent for repair. It is attached to the deck with 4 screws (see photo). I was wondering whether I should do something to fortify the screw holes whilst the deck plate is being repaired. This way when I reinstall the deck plate it will be "stronger than ever". Not sure what I should do exactly. Should I just pour some epoxy in the holes?  Any suggestions?

I do not have access to the underside of the deck. IMG_20210905_125616.thumb.jpg.e71fa35abb6ac16532e1bf1f9474a8d9.jpg

Typically helicoils or threaded inserts 

Ask a composites guy for the best solution for your laminate thickness 

the common rule is that laminate thickness must equal bolt diameter 

6mm laminate ….6 mm fastener 

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43 minutes ago, allweather said:

Point of interest, were they lose after the damage? If they weren't there may be nothing in need of fixing.
It's also the mast step, most force is compressive and not carried by the screws so back to the above, is there any actual need?

I'd agree with this. 

If there's now damage so that the screws can't be tightened down firmly I'd fix it.  I'd drill out oversized holes, probably at least 4 times the diameter of the screws. Fill with epoxy thickened with micro fibre and redrill.

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5 hours ago, allweather said:

Point of interest, were they lose after the damage? If they weren't there may be nothing in need of fixing.
It's also the mast step, most force is compressive and not carried by the screws so back to the above, is there any actual need?

You're right. They weren't loose. I just wanted to be cautious considering I have the opportunity to do so. The boat is from 1985 and I suspect that those screws have been there since. Therefore I was thinking it might be wise to strengthen things a little. Maybe I will just dumb a little epoxy in the hole before screwing the plate back on. 

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In that case sealant should be sufficient(or epoxy I suppose but more of a pain to clean. May want to lubricate the screws though I don't know with what besides release wachs to avoid issues in the future).

Safe yourself the work and sail instead, it will be fine.

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6 hours ago, SloopJonB said:

^ This

Mast steps are under compression so the screws are acting more like locating dowels than fasteners.

Well there's probably some element of shear load involved in the joint, so keeping it tight against the deck would be important.

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Take a screwdriver and hand screw one in each hole. If they are not wobbly after penetrating the thickness of the laminate don't worry about it. Likewise once you hand torque them, if they tighten up as usual don't worry about it.  

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i wouldn't worry to much about the screws .. if you feel guilty enough then painting a small amount of epoxy around the inside of the screw holes wont be a bad thing

( as a seal for the glass ..  dont build it up to much as the screws were tight enough )

i would use some silicon on the footing to seal it though

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