1974. O’Day 20 Interior Refurbish

[def]

My 20 sails fine. The interior, however, needs some help. I will probably have several questions, but I will post them separately.

First problem is the bulkhead. The starboard wall is in ok shape. It does not touch the ceiling, so I assume it is not structural. The port wall has a 1x1 that goes from a metal plate on the ceiling to the floor. I assume that this board is the main structure that supports the mast. The port wall is in rough shape. It has some rot along the bottom.
Can I easily remove and replace these bulkheads? There are screws. What should I replace it with? I have seen pictures of 20’s with the bulkheads removed and a center post installed. Is this a good idea?

Thanks for any advice you can share.
David

 

[Will Gilmore]

It does not touch the ceiling, so I assume it is not structural.

Not a reliable guideline here. Thre bulkhead may not be structural, but the height is not an indication, since internal structures help keep hull form, not just deck to hull support.

Can I easily remove and replace these bulkheads?

A well braced hull is probably ok to pull any one part for repairs. Do them once at a time to completion before moving on to the next area.

I have seen pictures of 20’s with the bulkheads removed and a center post installed. Is this a good idea?

It is not uncommon to see this change in either direction. I, for one, would like to get my compression post out of the way.

Good luck and I look forward to following your repairs.

-Will (Dragonfly)

 

[rschuss]

It cost money for a manufacturer to put items into a product. If it were not necessary, it wouldn't be there. Let's say each stay has 200# tension. You have starboard and port stays pulling up the sides. There has to be something under the mast to appose the force of the downward pressure due to force of the side stays. It shouldn't be the deck. Don't forget the fore-stay and back-stay pulling on the ends. As for the bulkheads. If they are rigidly fixed to the hull, there would be a hard place at that point; and soon the hull would fracture and fail. Don't doubt the forces at work and the designer's effort to keep the structure safe from failure. When you replace the port bulkhead, remove it carefully; and notice how it was installed. Take pictures if necessary. Make it the same size and install it the same as original. Be careful to do a good job and maintain the value of your boat. You may want to move up to your next boat. Be safe; and have a great sailing experience.

 

[Timm R Oday25]

I just replaced the starboard bulkhead on our '81. The outer curved part of the bulkhead did not touch the hull. This way the hull was allowed to flex ,rather than create a point to fracture ..It's a better sign that the bottom rotted out than the top. There was likely standing water in the bilge for a period of time. If the top had rotted ,it would suggest leaking deck through attachments ( cleats and winches )and spongy deck that would require substantial repair.
Before installing the replacement bulkhead ,I suggest LIBERALLY coating it with a water proof sealer of your choice .On our boat it's Deft outdoor polyurethane semi satin .This way if there is every a leak from above it wont affect the bulkhead to which your stays are attached

 

[Noodat Lady]

My O'Day 20, acquired this summer, also has a bulkhead issue. Slightly more radical I think: there is nothing between the crown of the cabin beneath the mast and the floor (sole?) of the cabin. The ante-previous owner seems to have been the culprit. He removed the bulkheads and installed a slightly arched wooden beamlet that is epoxied to the ceiling, although not in contact for the starboard 6 inches or so. I cannot see signs of stress on the decking/cabin, but then I am neither knowledgeable nor observant. The boat has been sailed numerous times since this modification, but since my blissful ignorance has now been clouded by this new information about the structural importance of bulkheads, I imagine that I should attempt some remediation. Could I put some kind of a post in place to take the stresses? If so, any guidelines would be appreciated. I am attaching a recent picture, plus a picture from a 1974 magazine article showing what it would have looked like when new.
Bob

 

[def]

Noodat Lady.
Others are far more knowledgeable than me, but from what I have read, a post of some kind would be a good idea. Something has to support the mast, and people walking over the cabin.
What kind of flooring do you have? It looks good. I need to do something with ours. It is currently the stained original.

 

[Noodat Lady]

Yes, it's the "what kind of" post or other structure that I am hesitant about installing without more knowledge than I have at present. Since apparently the bracing should not be too rigid, I was thinking about making pads out of dense rubber matting (stall mats to be exact) which would allow some flex and shock absorption. But maybe there are proprietary posts available for the job?

Flooring: probably "distance lends enchantment to the scene" since it is nothing special. On top of what I assume to be the original marine ply floor is an inexpensive-looking outside patio sort of thin rough carpet. Does the job perfectly well and seems in good shape despite apparently being down for a long time.

Bob

 

[def]

I hope to take the bulkhead apart over Christmas. I will report back what the original looked like.

 

[Louden Ness]

I have a '73 model that was basically given to me. In pretty rough shape, though. I had to gut the interior and just about start over. Structurally, I basically replaced what was there with new plywood with a lot better tabbing/taping to the hull. I never liked the way the bulkhead, step, windows and chainplates were set up so I overkilled it. The original bulkhead fit into grooves molded in the cabin liner. Probably right around the wood beam on your boat. I ended up with little portholes instead of the windows, a new bulkhead glassed into the groove plus a stainless compression post through bolted to the step plate. At the bottom I built up from the keel to support the post that fastened to the cabin sole.
With your boat I'd be worried. Without that bulkhead there is no support. The holes for the windows are the weak points in your case.
With what you have, here are my suggestions. If the beam is lined up with the molded groove the step plate should be right behind it. Find the spot on the cabin sole that is directly under the step plate. Devise a way to carry the compression load to the cabin sole. A piece of 1" thick wall rail tube is enough for the job. If the beam is directly under the mast do about the same except fasten to the beam at the top. The cabin sole might not be stiff enough and a plywood pad might be needed to spread the load.

 

[Noodat Lady]

Thanks for that. Very interesting and sensible-sounding recommendations. I would love to see pictures of what you have done, when you get a chance.
Bob

 

[def]

With what you have, here are my suggestions. If the beam is lined up with the molded groove the step plate should be right behind it. Find the spot on the cabin sole that is directly under the step plate. Devise a way to carry the compression load to the cabin sole. A piece of 1" thick wall rail tube is enough for the job. If the beam is directly under the mast do about the same except fasten to the beam at the top. The cabin sole might not be stiff enough and a plywood pad might be needed to spread the load.

Excellent information. Thanks so much. I do have a question. Where would I find a proper tube for the compression post? I have googled to no avail.

 

[Louden Ness]

I ended up getting mine from onlinemetals.com

New bulkhead

Window filled in

Little square is buildup from keel

I'll post a few more pics after I resize them. I'm getting ready to go anchor in the middle of a nearby reservoir and quarantine the rest of the world for a few days, so I'll have plenty of time for that.

 

[Louden Ness]

A link to the tubing:

Find the Right Plastic and Metal Materials | Online Metals

Buy plastic and metal materials at OnlineMetals.com®. Not sure where to start? Our easy-to-use filters will help you find the materials you need.

www.onlinemetals.com

 

[Noodat Lady]

That certainly looks strong. Getting a bit dark in there though!

After a lot of searching of forums, it seems that a 2x2 hardwood post serves as well, and is often used. Pre-stressing the roof with a jack before inserting a post seems advisable too.

I, being a notorious cheapskate, am planning on using hardwood stair handrail. From any builder supply.

 

[Louden Ness]

In that first pic you can see a scissor jack & 2x2 that I used until the new bulkhead was in place & epoxy cured.

The wooden stair railing should be fine, especially if you seal it with a coat or 2 of epoxy.

One of the reasons I went so deep into it was a serious oilcanning problem when I got into waves. Another reason was to beef it up for a 150% genoa.

 

[Noodat Lady]

150% genoa? You are obviously a serious sailor, whereas I am a fair weather wimp. I think yours is getting close to Blue Water capable.

 

[Louden Ness]

It's probably not going to be used a whole lot. I'll be coastal sailing in the Gulf of Mexico when all is ready. That's blue enough for me. Sometimes very light wind but I can always douse the sails and run for cover if I need to.

 

[Louden Ness]

Here we go.

This is an example of separated stringers. Tape was fiberglass mat, not woven. Broken in several places and probably the cause of a lot of the oilcanning.

Another bad spot. Tape never bonded to the vertical part.

V-berth removed and front part of liner cut off. Nearly all of the tape to the hull was broken.

New marine fir frames. Mahogany ply is located the same place as the front of the old liner. Extra frame ahead of it so the 9 gallon water tank has good support. Everything ahead of that was filled up to berth level with 2 part foam.

Because of various types of gel coat cracks on the hull, I decided the boat had been beaten up by one or more of those storms that has a name. I put a layer of biaxial glass up to the waterline and used biaxial tape to bond the frames and stringers.

 

[Noodat Lady]

Wow! That is impressive work. Should be hellish strong now.
The 2 part foam is a special marine variety? No using the cans from Walmart?.....

That boat has a story or 2 to tell, for sure.

 

[Louden Ness]

Definitely not the stuff in the spray can. Can't remember which place I got it but it was some marine supplier.
I took my time with all of it, surveyed and sketched and planned for a few months and divided it up into an ordered series of tasks. I had the big picture but focused on each task. When I finally stepped back and looked at the whole thing...

It didn't look like an O'day 20 any more.

We know what it is!