Catalina 27 keel bolt sistering?

[afiore]

Hello! I am new to this forum. Just bought a 1975 Catalina hull #2056. The keel bolts and nuts are rusted/dissolving, in really bad shape. The keel, however, seems firmly attached, with no Catalina Smile and what appears to be a nice smooth fairing. I am interested in sistering some bolts,and got the famous drawing faxed from catalina. They are currently looking up my hull # to tell me if I have a lead or iron keel. Can anyone provide any guidance on the process? I know there are two alternatives, one is using lag screws, the other using bolts with a hole drilled from outside the keel as well as from above. I don't clearly understand the process, and how involved it is. This is my first boat and I don't normally do work like this, although I am quite handy with other things, like car repair. My impression is that lag screws are only for lead keels, and the other bolts are for iron keels. Wrong or right? I read somewhere in a forum that drilling a hole in the keel from above for a bolt can take a day per hole, and require a drill press. But then the nice lady at Catalina said I could probably do it myself if I was "handy". Any information, the more specific, the better, would be greatly appreciated.

 

[Gerry, GMJ Marine]

keel bolt sistering

Forget the lag screws. I'd consider them a short term, temporary fix at best. A good (bad) grounding or hard bump could cause them to tear out at least partially if not completely. The proper fix would be using bolts. Let me try to clarify the installation for you. It entails some careful measuring. Determine how many bolts you'll install and where. Because you'll be drilling through the keel from side to side try to locate the new bolts between the existing ones fore and aft so you won't hit them when you drill through. This will give you a row of holes from the leading edge to the trailing edge. Now if you measured correctly when you drill vertically down through the keel sump into the top of the keel the bit should come out in each one of the lateral holes. Attachment is accomplished by inserting a threaded rod of the appropriate size and material and length, down the hole into the keel. A couple of nuts and heavy washers on the end of each one, pack the lateral holes with thickened epoxy. If everything was done right you should have enough bolt in the keel sump for a washer and nut. I didn't suggest what materials for rod or hardware as you'll probably want to investigate this on your own. Hope this gives you a better understanding of whats involved.

 

[afiore]

Thanks for the reply Gerry

Thanks for the reply Gerry! Could I ask a few follow up questions?What kind of drill bits, and drill would I need to make the holes? Specifically, what composition? I am still trying to find out from catalina whether I have an iron or lead keel. Would the keel type make a difference to the drill bit?I understand the through bolt concept, But it seems I'd have to make a pretty large side hole in the keel to accomodate the nuts from below. Would this require a special drill?Can I put two new bolts next to each other side to side, like the original keel bolts, or just one? Would the side hole need to be drilled from one side of the keel to the other, or just the the point where the bolts come through?And finally, would the holes in the keel where the bolt shafts go through need to be filled with epoxy around the shafts too, to prevent leaks?Thanks for your reply!

 

[afiore]

follow up question

I received more info from Catalina. They say lag bolts are not the best way to go. Better to put in 4 through bolts made of 316 stainless threaded rod, 1/2 inch diameter. The holes for the rods need to be drilled vertically straight through the bilge and into the keel about 4 inches down. Then crossing holes should be drilled from outside the keel to intersect with the vertical holes. Then a 3 inch long, 1 1/4 inch diameter round rod with a threaded hole drilled into its side accepts the bolt, and gives extra pullout strength.The question is, how hard will it be to drill the keel, assuming its iron? I have found cobalt drill bits online of 1/2 inch diameter to drill the holes from above, but how would one make a 1 1/2 inch diameter hole going sideway across the keel from one side to the other?