J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Yet another transom core repair post.

Howdy J/30 Community,

I recently purchased Quicksilver here in Juneau Alaska. She's been on the hard since then and I've been taking the opportunity to do long term/differed repairs.

What started as a repair of what I thought was a small soft spot in the transom turned into (no surprise here to you all I'm sure) a full blown core removal, replacement and reglass. Damn whoever made the decision to leave the core exposed to the thru hulls. Anyway, here's where I am with the repair so far. I could use some advice here.

I removed the thru hulls and cut off the outer skin in manageable chunks until I found solid dry balsa. Then, because I live in SE Alaska and it rains all the time, I sealed the inner skin and the exposed balsa with West Systems 105 epoxy so that it would be protected in the meantime.

Living in Juneau it is difficult to get materials locally, especially coring material. But, I can get fiberglass sheet, mat, and epoxy, and cedar lumber. I purchased 1.5" x 1.5" cedar and cut it into 0.7" thick wafers to match the balsa thickness. My plan is to roll 105 onto the cedar end grain to let it soak in then glue the blocks onto the inner skin with thickened epoxy. This cedar is clear grain, but looks to be fast grown so pretty lightweight. I figure it will be almost as light as the balsa, but more rot resistant. Once the core is replaced, I'll re-glass the outer skin. I tested this out in a small area and it seems to work pretty well. I squished epoxy between the cedar blocks to bond them together as well as to the inner skin. I was also planning to cast some fiberglass reinforced epoxy blocks to cover the thru hull holes which I will then drill out for the new thru hulls giving quite a bit of solid, impervious core around the thru hulls.

While I was working on this the guy who owns the yard came over and basically told me that this plan was stupid and that I should rip out all the cedar and just rebuild the whole transom with solid fiberglass with no core. Granted, this guy mostly works on fishing boats or powerboats, so he doesn't have experience working on sailboats.

My questions:
- Should I listen to this guy? Is solid fiberglass the way to go?
- If coring, then is my cedar plan viable? I could order some core materials, but it would be pricey.
- After reading other posts about transom repairs it seems that the exhaust is a problem area. This area seems solid on Quicksilver, but should I address this potential problem are while I am at it? If so, what is the best way to tackle this?
- Should I add some blocks to mount a future swim ladder?
- What are this forum's recommended thru hulls?

Here's a link to photo album: https://imgur.com/a/pTZN2DP

Thanks in advance!

This will work. Experience from my J/30 Rhapsody recore blog and this old forum post.

My questions:
- Should I listen to this guy? Is solid fiberglass the way to go? - no - properly isolated core is stronger and lighter
- If coring, then is my cedar plan viable? I could order some core materials, but it would be pricey. - your cedar approach looks good. You may save yourself some time if you "glued" it to a mesh fabric screen off the boat, then use the sections cut to size and place in the area to recore.
- After reading other posts about transom repairs it seems that the exhaust is a problem area. This area seems solid on Quicksilver, but should I address this potential problem are while I am at it? If so, what is the best way to tackle this? Remove the exhaust tube and make the entire area around it solid thickened epoxy with a new tube glassed in to isolate from the core.
- Should I add some blocks to mount a future swim ladder? Yes! I did the same using solid glass so there could be no leaks into the core.
- What are this forum's recommended thru hulls? I was able to salvage the original valves. My J/109 has Marelon valves which will never corrode and if I did this again would size for the appropriate valves.

ps - You are doing it the way I should have done it from the outside. I thought I would save work doing from the inside, but it was harder because of the access,