Looking for help - forming ribs

Jim Tesno · Post by **Jim Tesno** » Fri Sep 11, 2009 5:30 pm

Well, I'm pretty well done with taking things apart and am getting ready to build a steambox. From what I have read so far, it seems that the ribs are steamed and then put in the boat, using the hull as a form. My problem is that the bottom is warped from sitting on the front rollers and rear bunks so its concave from the bottom looking up at those points..

Would it make sense to make a jig that I could transfer the shape to and bend the pieces on it and then, once the bend "sets", I could put the rib in the boat. I'm thinking of a couple of planks bolted together with numerous holes I which I could move pegs around to the proper shape (sort of like a big kids lite brite). If this works, I'd have to figure out some type of bendable metal or wire that I could use to initially form the shape and transfer it to the jig.

Does all this make sense or are the gurus out there laughing at this rookie already?

gts · Post by **gts** » Sat Sep 12, 2009 8:03 am

Jim, how much of the hull is left? A fast way to get rid of the hog and concave bottom is the Wade Strong "hull-jacking" method. Basically, apply hydraulic jacks inside the hull to jack out the ribs back to fair. (Just search the Forum for details.) I'd fair the hull first and then start replacing ribs one by one in place, rather than try to build forms to bend to.

George

Jim Tesno · Post by **Jim Tesno** » Sat Sep 12, 2009 10:25 am

George;

Basically all the ribs are rotted from the waterline/floor to the keelson, most are either totally gone or the remnants of wood would crumble if you tried to pick up a piece.

gts · Post by **gts** » Sun Sep 13, 2009 7:53 am

Jim, you only need a couple of inches of solid rib. If the rib will support pressure from a 2x4 block without crumbling, then hull jacking will work and you can use the hull to help form your new ribs. Just locate which ribs over the worst dents in the hull, put a 2x4 piece across three (or more) ribs centered on the highest, and start applying pressure. Once you've nudged the hull back to fair, you can use it as a guide for bending the new ribs.

If your existing ribs are going to crumble under any applied pressure, I'd make up a 2x4 scrap piece with its own "ribs" attached - both to distribute the load over the section of hull and provide clearance between the hull and the 2x4 block to allow you to insert the new full-length ribs - and use those to fair the hull first.

George

Phill Blank · Post by **Phill Blank** » Sun Sep 13, 2009 9:03 am

Jim,

If your ribs are as bad as you are saying what shape is the Keelson, garboards and outer keel in?
If they are rotted or soft and need repalcing, then the hug in the hull will be straighten out when these items are replaced and you will not need to try jacking the hull.
Replacing the Keelson, it's sisters and the outer keel is the first order of business if they need to be replaced or are even questionable. That is the back bone of the boat and should be treated as such. No patch work guilt here.

Good Luck,

Phill