Replacing those pesky to-hull pipes

[Jim]

Well as part of the upcoming haulout, I want to replace those glassed in to-hull pipes that look like a desaster-in-waiting. Planning is coming along well and I've searched the archieves for info and looked at Don Casey's description of how to do it, so the knowledge base is in good shape, except for one question.  About how thick is a Catalina 27 hull at the point where the to-hulls are? This is about 11-1/2 foot back from the bow and about 2 foot up from the centerline on either side. Thanks, Jim

 

[Peter]

Garry's writeup

Have you found Garry's writeup for Tashtego in the archives. The writeup has everything you need to change all the through hulls plus more and it's about a C27 too. I think the date of the writeup is 6/27/02.Peter

 

[Jim]

Gary's thru hull writeup

Yes, thanks...just want to know because right now I plan on thru bolting the seacocks, and to buy the proper bolt length, I need some idea of the hull thickness. Thru bolting may be overkill, with a mounting pad caulked to the inside of the hull, but if I have the stuff ready, then the job will get done a lot faster. I really don't want to make more then one or two trips to the boat store during this haulout.

 

[Garry@S/V TASHTEGO]

Thru Bolts

The simplest thing to do is to buy flat head bronze machine screws (West Marine has 'em) that are plenty long. Install them from the outside and snug the nuts up then cut them off with your grinder or a hacksaw on the inside. Using stainless for this job is not a good idea if you are using bronze thruhulls and seacocks. If you're using marelon then ss is still less than ideal below the waterline. As I noted in my write up I glued the backing plate down then screwed the flange to the backing plate and didn't drill through the hull (I was naughty and used an ss lag screw but it is not under water). You will notice right away if the seacock moves even a quarter turn as the handle will point in a new direction. Your choice. Pay attention to the orientation of the handle and how you will manage to open and close it. Make sure it doesn't foul anything else and your hand will survive the job without getting squashed or slashed. Simple but important.There's a good article in the latest issue of "Ocean Navigator" on thru hulls and seacocks.