For those that have upgraded your eyebolts — as I look at the new hole diameter did you oversize and epoxy fill to drill again. ? Wondering how that played out if anyone went that route .....
Chainplate Eyebolt question
- Thread starter pclarksurf
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My eyebolts were already 1/2", but (apparently) an older style of 1/2" that didn't screw to the deck, so they could still rotate. Some clearly had, and had leaked at some point, but not enough to really impact the core.
With a 1/2" hole already, it was easy to get a dremel head in to grind out some more core (without over-drilling the fiberglass skins). I filled with epoxy and re-drilled, all at 1/2". Hope that made some sense.
For the screw holes in the eyebolt plates, I didn't through-bolt. But I didn't want screws straight into the wood core. So I overdrilled those (maybe to 1/4"? I can't remember), filled with epoxy, and put the screws in covered in wax while the epoxy cured. That makes something of a pre-threaded epoxy mount point (with sheet-metal threads from the screws) that you can screw into when assembling (and still get the screws out if needed).
More recently, I've done something similar for other screw-mount items, drilling ~1/4" holes, filling with thickened epoxy, and tapping machine threads into the epoxy. That method seems easier and less time-sensitive. And we're not looking for a lot of pull-out strength. Just enough to keep the bolts from rotating.
I think I recall a Practical Sailor article comparing the strength of various mounting methods - tapping into thickened epoxy isn't super strong, but not bad - plenty for this application. It's stronger if you shove some fiberglass in so you're filling with a mix of glass + epoxy. But that's probably not needed here.
It will take a few rounds of tightening with a torque wrench (over a few warm days) to squeeze out all the butyl and get your bolts tensioned right. A few more notes at my original post, but I think I said it all again here.
With a 1/2" hole already, it was easy to get a dremel head in to grind out some more core (without over-drilling the fiberglass skins). I filled with epoxy and re-drilled, all at 1/2". Hope that made some sense.
For the screw holes in the eyebolt plates, I didn't through-bolt. But I didn't want screws straight into the wood core. So I overdrilled those (maybe to 1/4"? I can't remember), filled with epoxy, and put the screws in covered in wax while the epoxy cured. That makes something of a pre-threaded epoxy mount point (with sheet-metal threads from the screws) that you can screw into when assembling (and still get the screws out if needed).
More recently, I've done something similar for other screw-mount items, drilling ~1/4" holes, filling with thickened epoxy, and tapping machine threads into the epoxy. That method seems easier and less time-sensitive. And we're not looking for a lot of pull-out strength. Just enough to keep the bolts from rotating.
I think I recall a Practical Sailor article comparing the strength of various mounting methods - tapping into thickened epoxy isn't super strong, but not bad - plenty for this application. It's stronger if you shove some fiberglass in so you're filling with a mix of glass + epoxy. But that's probably not needed here.
It will take a few rounds of tightening with a torque wrench (over a few warm days) to squeeze out all the butyl and get your bolts tensioned right. A few more notes at my original post, but I think I said it all again here.
thanks for that-- was wondering out loud if "hogging it out" made more sense than actually over drilling. Now that I'm staring at the drill bit it is bit more realistic. Good call on the fitting screws-- I'm stealing that.