Replacing ribs and keel board 21' trailer sailor

[psk125]

So... dry it all out & have at it. The pieces that have come "untabbed" from the hull will have to be reattached with new 'glass over them, but probably don't need to be replaced unless they're really rotted out. Grind things back to give "tooth" for the new fiberglass to hold on to, and put perhaps three or four layers of mat & roving where they're needed. Don't mix up too much resin at once - it can kick before you've finished using it all, and you end up with a big lump of relatively expensive plastic to throw away before you mix up more.

[Spot]

Thanks PSK125.

Is there a reason why mat and roving would be preferable to cloth for this repair?

I seem to always have cloth, I'd need to source mat and roving.

Yes, nothing like a pot of resin going off prematurely to educate one about planning out batches.

Unless I find a heated space, this repair is at least 3 months out.

Thanks!

[MartinR]

Roving gives strength. You have to alternate roving and mat. Roving on roving is a no-no.
Cloth for the last layer is good, gives a nice surface.

[psk125]

Roving and cloth are synonyms. Mat puts distance between the layers of roving, creating a stronger "sandwich". You could make your own mat by simply chopping up pieces of roving, but it would be really messy, might not end up looking too good, and be a lot of work. I've used multiple layers of roving without mat - depends upon what you're doing - but using it with mat should be stronger.

[Adelie]

Roving and cloth are not synonyms but they are related and blend into each other.
Both are woven, sometimes on multiple axis’. Cloth is woven from threads and roving is woven from much larger yarns.

As threads become thicker at some point they become yarns. The dividing line is a bit arbitrary.


Roving is supposedly cheaper to buy but the big advantage is how fast you can build up thickness with roving compared to cloth.

[Spot]

Separated by a common language...so here is a picture!

from the good folks at https://www.expresscomposites.com/

[Jim Cate]

Not a pro, but in my limited experience, rovings are hard to bend to small radii. I suspect that it will be quite difficult to get any roving to accommodate to the shape of the floors. More layers of thinner, more flexible cloth will give a better result IMO.

Jim

[Spot]

Everyone, thanks for the replies.


Having to redo 'previous owner work' seems to be a thing with kit boats. I am still going back and forth about whether to fix all this first or test sail first to identify other potential issues.


I just got to thinking (dangerous, yes?) and these thoughts led me to the rear cockpit hatch and what is below. Correct to say rear lazarette?


On my boat, the entire inside is a cavity where one can see from the boweye bolts all the way to the inner transom.



Previous owner had the battery, main electrical box , and -based on the motor lift and matching hose boot mounted on the transom- a remote fuel tank.


If I get a gasoline powered outboard with a remote tank, shouldn't this area be bulkheaded, vented, and bilged separately from the cabin, and main electrical moved elsewhere ?!?


It would also seem like a bulkhead/sealed compartment there could also be a safety feature in case boat and rudder were parted by the gudgeons being ripped from transom.

[MartinR]

Originally Posted by Spot

shouldn't this area be bulkheaded, vented, and bilged separately from the cabin, and main electrical moved elsewhere ?!?

It would also seem like a bulkhead/sealed compartment there could also be a safety feature in case boat and rudder were parted by the gudgeons being ripped from transom.

Exactly! Especially the first point.

And, yes, why not sail first. She will hold together for a while yet.