I've got a gut bush engineering feeling that pad eyes are probably not a good idea.Private Eyes wrote: ↑Thu Oct 01, 2020 5:04 pm Hi everyone,
I have had an idea in relation to this issue of bolts breaking.
Now we all know it is due to corrosion where the us bolts go through the deck, and that is where the corrode, and then crack and then break.
My thought is why not replace with Pad eyes.
I am even thinking because I run upper and lower shrouds / stays, that i would place 2 pad eyes each side one for each stay.
Now my reasoning here, is that the eye itself does not go through the boat it is welded to the pad / plate. And then in me purchasing 4 of the 90mm size pad eyes, I have pad eyes that are rated at 4000kg, and secured by 4 8,5mm bolts through the deck. The chance of more than 2 bolts corroding at a time per pad eye, is highly unlikely, so with 2 bolts remaining in the eye, the mast would still remain upright, with the sails lowered. But with me having 4 pad eyes, I would be very unfortunate to ever lose a mast out on the water.
Anyhow, I have asked Peter T, as to what he thinks, but whilst I await a response, it would be interesting to see what other members think of this idea.
Here is the link.
https://www.metalhardwaresupplies.com.a ... steel.html
That photo with a $3 pad eye, its definitely very weak, i can see press in joins to the thin pad. The cost is too low. It would fail quickly within seconds for sure if used as a chain plate. All pad eyes have the load going through a right angled dogleg, its not a strong configuration, could shear off.
I'm going to stick with U bolts as designed and check them periodically.
The loading on the U bolts is straight down the shank of the bolt, so must be strong, its all in tension (no shear). go up a size or two from standard Investigator U bolts and check them (by pulling them out) before a big offshore trip. like the U-bolt from Witchards in the US, they have solid shanks all the way through, and a top plate carefully welded to it.
Radically changing anything like the chain plate configuration would need a professional yacht designer/engineer or rigger to oversee it.