keel bolts

[Thaddeus J. Van Gilder]

here's the question. My Rhodes has new keelbolts, but there are no obvious lead bungs in the bottom or the side of the keel. any ideas why thios is? They aren't lags as there are nuts on their heads.

thoughts? is it possible that lead bungs were used and they were "soldered in place?

Thad

[Rich VanValkenburg]

I don't own a Rhodes, but Sonja's bolt pockets were filled with melted lead. The outline of the pocket was hard to see. I sanded, and then scraped the ballast to find the holes. Once I'd found the outline, I drilled a half inch hole and then used a torch to melt away the rest of the lead. It came out clean since there was no antimony in the lead filler, and left a clean pocket. Toughest part was melting the lead from around the nut. The torch wants to pop back when the flame is confined to a small area like a bolt pocket. I wasn't being careful at first and almost had a melt-down of the torch after it popped.

Rich

[Lulworth]

Nat. Herreshoff sometimes drilled slightly undersized blind holes in the lead and then used end-threaded bronze rod to self-tap (lead is soft) the rod into the lead. It's a royal pain in the @@% to deal with 75 years later. Go ahead, ask me how I know!

David.

[Thaddeus J. Van Gilder]

I thought the Herreshoff boats used lags to bolt on the keel!

[RGM]

What you might be looking at is a situation where you're keel bolts are actually hanger bolts. One portion (the keel end) has the threads of a lag bolt machined on them, then there is a portion with no threads machined on them (full diameter thru all of the wood) and then a portion of the bolt (the upper end) which is threaded to receive the nuts that you refer to.

[Lulworth]

Thad, Lag Bolted? Not in the traditional sense of the word lag bolt, at least not the s-boat. What I have are bronze bolts up to 3 ft long that pass through the floors, keel timber, and (in places) the dead wood and terminate in a blind hole in the lead. The bronze rod is threaded at each end and is turned into the lead cutting a thread in the hole as it is turned then finished at the other end with a nut ontop of the floors. I hear (I haven't tried it yet) that keel bolts like these are effectively "cast in place" though some say you can back them out if the bolt is still solid enough not to shear shear when turned with a lot of force. In which case you might as well have not bothered!

David

[Ed Harrow]

One of these days someone will try out my idea of putting an arc welder across the bolt and ballast and gradually turning up the power. Seems like it might just free things up a bit. smile.gif

[Dave Fleming]

And as Ed turns up the juice on his trust Miller a "thud" is heard all over the neighborhood and his keel decends slowly to China. :D

[trull]

For what it's worth,when working on a project building a LFH Araminta, we found that the lead ballast had to be tapped using a thread-forming tap which rolled the threads into the lead rather than cutting them. I think we used dish detergent as a lubricant.

[Dave Fleming]

Agreed Trull, to be able to really tap threads in lead you have to up the Antimony content quite a bit and even then I wouldn't trust 'em with that stress load.
And too much Antimony and you can wind up with a keel in many pieces if not re-inforced with an interior armature. ;)