Excessive reinforcement?

[Brian S]

Having removed the swim ladder on my 192 to better polish the transom, I am now replacing 3 individual wood reinforcement blocks with a single sheet of 1/2" fir external ply.

Do you all think I should coat the ply with epoxy? Fir will still check with an epoxy coating. Also, if I bed the fasteners properly, there ought to be no water touching the ply.

Should I epoxy glass fabric on one or both sides? Theoretically, a solid sheet of ply will be stronger and less likely to allow the ladder to torque, so the additional strength of glass layers shouldn't be necessary.

Should I epoxy the ply to the inside of the transom? Again, I'm thinking a solid sheet of ply should provide more support than the individual blocks, so again this should be unnecessary.

Thanks for your opinions helping talk me into or out of more work!

Brian

 

[TLW]

Unless your transom is absolutely flat, OR the ply is shaped to fit, glassing it in will cause "hard spots" that show through. The individual blocks are a better idea, glassed in if you like, and with large fender washers.

 

[centerline]

if the wood is completely dry before coating it with epoxy, it wont check. plywood is nearly as good as anything else you can use for that purpose.

the mechanical stress's on a swim ladder is causing it to want to push into and downward on the hull at the lower attachments and outward and downward on the upper.

I am a fan of using the largest backer block.plate that fits, but at the very least I would use backing blocks that span the upper two bolts, and another one that spans the two lower bolts... unless the shape of the transom prevents this.
im also a fan of having stainless plates made for the outside lower bolts so it helps spread the stress of the ladder connection as it pushes in on the transom when a big guy is on the ladder with the boat rocking

as for glassing them in on the inside, its unecessary and will only cause problems if you ever decide to get a different ladder or do a repair.... the glassed in blocks will be in the way/wrong spot.

 

[Brian S]

These are good thoughts, guys.

I think I'm going to try out my plywood plate, and see how it goes. If I notice any strangeness, I'll just swap it back out with the original wood blocks.

Brian