Steel shoe ballast

[Oddbjorn]

I am building a Bolger sharpie called William D. Jochems. The original design has water ballast in two tanks against the hull side. My edition of the plans show an alternative with a 3/8" steel shoe under the whole flat bottom. This is an option if you don't need a low weight for trailing. It will also make the boat stiffer under sail and protect the bottom.

Phil Bolger & Friends has an detailed description of how the steel plates should be fastened and how the through bolts should be made watertight. The shoe is is divided into 15 sections and there is 72 bolts through the bottom.

What I would like to know is if anyone has tryed this and if you managed to keep the the bottom free from weeps and leaks.

Thank you!

Kind regards
Oddbjorn

 

[whitepointer23]

What about epoxy or sika. If you can bond the plates to the hull there will be 72 less possible weeps.

 

[Oddbjorn]

In a way Bolger comments on this solution in his supplement to the Plans Key. He suggest to bed the steel plates in 3M 5200 applied in simple beads along all four edges of each plate and around each bolt hole into the plywood bottom. He is limiting the use of bedding compound to make it possible to remove the steel plate sections. I think I will follow his advise on this.

I still hope to find someone who has tried to use steel plates as ballast beneath a flat bottom.

Regards
Oddbjorn

 

[PAR]

Welcome to the forum.

If you don't want leaks or rot, epoxy bond the fastener holes, then bed the plates in 3M-101 or similar, so they can be removed without damage if necessary, which isn't likely with 3M-5200. Also epoxy coat the plates themselves, with at least 3 coats of neat epoxy, so they don't rust.