drilling chain plates?

[oyster]

My Nor'Sea 27 was made with an odd match of 7/32 wire and 3/8 turnbuckles. I'm replacing my standing rigging and am having a hard time finding fittings that match this combination. Since I don't want to downsize anything in the system, would it be a problem if I enlarged the holes in the chainplates to accept a larger 1/2" turnbuckle? This is the smallest size Suncor turnbuckle that will accept a 1/4" 7x7 (to match the strength of the original 1x19) wire and thimble for a spliced eye (remember this is an old Lyle Hess design). The chainplates are of the 1 1/2" x 1/4" outboard through-bolted variety. If this isn't a problem, then how would I go about enlarging the hole? Anyone have an objection to splices on a boat like this? You won't hurt my feelings, I haven't yet decided the route I'll take I'm just toying with ideas. However, even if I use modern mechanical terminals the 7/32 wire, 3/8 turnbuckle really limits my selection.

Thanks in advance,
Bill

[Brian Duff]

As long as you can keep a half inch above the hole your drilling and the hole is centered on that 1.5" width, go a head and get a 33/64 drill bit, sharp. You can use either a cordless or large 1/2 chuck drill and drill pretty slow, push hard and use as much oil as you can, keeping your deck in mind, Teak looks pretty messy if your not careful, and it adds hours to clean that mess up !
Use a fairly large drill liek a 14.4 cordless or big electric drill. You may consider drilling one or two incremental sizes. I will normally go straight to a 1/2" cleanced hole, but you be sure to hold on tight if you dont want to break bits or get hurt, and go slow.
Doesn't OS have a stud that will go from 1/4" wire to 1/4" stud or am I remembers something incorrectly ? I'll google that ...
Have fun. Brian

Or you could always just talk to Brion about getting some Hayn turnbuckles that are designed for 1/4" wire with a 3/8" pin. 38TFBS14 is the part number, I believe......

They do make some nice stuff............