O'Day 25 Bulkhead Replacement

Sep 24, 2018
2,549
O'Day 25 Chicago
There are plenty of posts about bulkhead replacements but very few of them explain anything about the process. Upon initial glance it looks pretty straightforward. Remove sink, cabinets and anything else in the way; Remove screws, cut and grid away tabing and replace. But this is a boat. Almost nothing is as straight forward and easy or cheap as it should be.
@cb32863 mentioned that the amount of chainplate above and below deck should be measured before removal. Many other people have stated that the old bulkhead should be used as a template. What other tips do you guys and girls have? I'm especially those issues that you did not expect. Also, How long did the project take?
 
Aug 28, 2015
190
Oday 28 St Joseph, MI
Depending on the amount of demolition in the boat I would take plenty of measurements from various points inside the boat to specific points on the hull to ensure the shape of the hull doesn’t change when the interior parts are removed. Years ago I read a book, “From A Bare Hull” by a guy named Mate’ (I think). He suggested the bulkhead should be installed with a small space between it and the hull, filled with a strip of foam to prevent hard spots on the hull. Then glass and filet both sides of the bulkhead to the hull. This may be overkill for a 25’ O’Day but if the bulkhead you’re working on is structural I would think simple tabbing to the hull wouldn’t be very strong.
 
Sep 24, 2018
2,549
O'Day 25 Chicago
I'd imagine a 1.5" or wider strip of 1/4" wood would work better to spread the load than a piece of foam. Perhaps I'm not picturing the right type of foam in my head. My understanding of the bulkhead is that it spreads loads between
the deck, hull and standing rigging. The types of loads would be tension for the rigging and tension and compression for the deck/hull. This is structural on the O'Day 25
 
Aug 28, 2015
190
Oday 28 St Joseph, MI
The foam I mentioned is just a spacer so the bulkhead does not sit with a hard spot against the hull. Mate said that the through movement of the hull the foam would likely desintegrate over time. The effect of this is the bulkhead contacts the hull across a 2” wide fiberglass filet rather than 1/2” of plywood with tabs. He was building out a Westsail 32 hull which I’m sure is built to endure a lot more stress than any O’Day. However the initial installation was accomplished when your boat was built was obviously satisfactory as it’s lasted a while.
 

JRT

.
Feb 14, 2017
2,039
Catalina 310 211 Lake Guntersville, AL
I'd stick with the exact same materials and design for the O'Day 25.

I didn't remove my bulkheads, I had some old rot in the Starboard bulkhead above the top bolts for the chain plates to plywood. I dried mine out with a space heater after resealing the cover plates from the topside and used Boatlife Git Rot Penetrating Epoxy. That was 2 seasons ago and they are doing just fine. Cosmetically it looks terrible because to make this product work you have to drill holes in the damaged area and fill with the epoxy until it runs out. I decided not to cover it and just continue to monitor it and plus it is easily visible to any future owner. I think this worked well for my issue as I had a small amount, maybe 3" x 4", of damage and the drilling showed a very solid bulkhead material.

https://www.westmarine.com/buy/boatlife--git-rot-penetrating-epoxy--P004_120_001_009
 
Sep 24, 2018
2,549
O'Day 25 Chicago
I discovered how bad the rot was about an hour after I bought the boat. The PO agreed to have some large steel plates fabricated for the front and back of both bulkheads. It extends well into the solid areas. He stated that he rebedded the chainplates about four years ago after he discovered the leak and damage. The rotted area is dry as a bone and he's been very upfront about other issues and maintenance. We both agreed last time we met that the plate should do the job but everyone else is telling me otherwise. I'd like to get an idea of how much work is involved with replacing it so I can make a decision
 

JRT

.
Feb 14, 2017
2,039
Catalina 310 211 Lake Guntersville, AL
Wow those are impressive plates. If it were me and the wood really is solid in the new attachment area, I'd be fine with that repair for now. Also if you could put me in touch with who did that and I might order a set for my boat just to cover the area better if they aren't too expensive.

You could also consider cutting the damage area out and glue and glass in some new plywood and then still cover it with the plates.

I'd paint those plates brown or cream to blend in better. Install them and go sailing and just monitor as a possible project later. Even when you tear out bulkheads and replace you still probably won't match.
 
Sep 24, 2018
2,549
O'Day 25 Chicago
He asked, "What do you think of this?"
I replied, "Bigger"
"How about now?"
"Bigger"
"How's this?
"Yeah I think that'll work"

He asked if steel was OK and I said so long as it's powder coated. A good powder coating job is really tough stuff. I'm totally ok with the black paint. He's been really good to me so I don't want to have him jump through hoops for things such as color matched paint.
 

JRT

.
Feb 14, 2017
2,039
Catalina 310 211 Lake Guntersville, AL
I think that will be just fine. I'd still be interested in a set for my 25 if he still has templates.
 
Jun 29, 2010
1,287
Beneteau First 235 Lake Minnetonka, MN
Replace the bulkheads, keep an eye on whether there is still water ingress. They hold up your rig, if that lets go its not a good day. Fix it proper.
 
Sep 24, 2018
2,549
O'Day 25 Chicago
The boat is very well wrapped up in a yard thats only opent till 3pm and is 1.5 hours away. Access is quite limited. Can anyone give me a rough idea of how much labor is involved with this process? It's the Starboard side
 
Jun 29, 2010
1,287
Beneteau First 235 Lake Minnetonka, MN
The boat is very well wrapped up in a yard thats only opent till 3pm and is 1.5 hours away. Access is quite limited. Can anyone give me a rough idea of how much labor is involved with this process? It's the Starboard side
Well, there is a good question..... I took a few days of finishing and sanding as I put a veneer on the marine plywood. It took an hour or so to cut the tabbing and unscrew each bulkhead. Then there is laying it out on the new piece using the old as the template. I filled the screw holes as I knew I would probably not even try to match up, just get the spacing about the same. So that was about another hour each side. I would figure another couple of hours to put it all back together. They aren't the easiest to get out of the companion way and you don't want to just toss them off the side as you need them in decent shape for a template. I would figure a full weekend for each, removal and installation, at a minimum. Your mileage will vary though as each boat and situation is different.
 
Sep 24, 2018
2,549
O'Day 25 Chicago
Once again, thank you Dan for a straightforward answer. Dedicating a weekend to this project sounds reasonable
 
Sep 29, 2013
36
Oday O'Day 222, O'Day 19 Casco Bay, Falmouth, ME
PR,
I replaced both port and starboard bulkheads on my O'Day 222. The PO must not have heard of sealants, because there were several iterations of extending the dinky chainplates on the 222 to find the next section of solid wood. Stopping the leak must never have occurred to him. The extensions ended up being about 2' on the starboard side and I could put my finger through the rotted section at the top near the chainplate penetration. All this leaking also allowed water to seep into the balsa core around the chainplate penetrations and about 4' along the top of the hull. I did use as much of the. original bulkheads as templates as I could, and then spent a fair amount of time fitting the replacements. The 222 doesn't use tabs, just bolts to the glass liner that forms the interior of the cabin base (seats, storage etc}, so I didn't have to deal with that aspect of the job. I did fully epoxy coat the replacements with 2 or 3 coats of epoxy, then varnish. I didn't like the dinky chainplates, so I added an extension over the original. The original were about 5" long, and now I have a 12" long chainplate. I didn't keep time for the replacement, and I didn't do it straight through in one long setting, but to get it right, I'd guess I have about 1-1/2 to 2 weeks in the project between removal, making the rough new bulkheads (I did replace the sink/stove cabinet as well), and perhaps more if you count the time for the epoxy to cure and the varnish to dry between coats. To get a really good fit takes some time, and a lot of ins and outs of the cabin with bulky pieces and then up and down a ladder. Don't underestimate the time, but if done well, the satisfaction you get and the additional value to the boat make the project very worthwhile.
 
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Ritdog

.
Jul 18, 2011
184
Oday 25 Portland, ME
I had to replace all of both sides of both 25s that I have worked on. They both had standing water of different depths in the saloon, and were delaminating. There are actually 6 full sheets of plywood needed to replace all the wood in a 25, if you include the galley assembly!
I used the old pieces for a pattern, which worked pretty well.
Used a floor jack on blocking to jack the headliner up a little when reinstalling the panels. Makes it much simpler to install. My one "mistake" was to go to 3/4" panel vs 1/2". Meant all my measurements were 1/4" off, which meant redoing all of the head wood and galley wood. It's much more solid now though, if 30 pounds heavier, and I like it.
Also had to replace the mast compression post (oak) as that was rotted out also. I epoxied the whole bottom 6" of that before varnishing the rest of it.
What you are looking at is the rotten bottom of the post in my new boat, and the delamination of my first one. Good luck!
I hope you don't have to replace your transom plates for the king plank and motor mounts. That is a nasty job, which I have written elsewhere in here about!

MAR_6713.jpg MAR_5267web.jpg
 
Jun 29, 2010
1,287
Beneteau First 235 Lake Minnetonka, MN
One per bulkhead for the main ones that the chain-plates attach to.