Epoxy clay as reinforcing filler

[sreidvt]

I am in the process of adding a teak beam (for a traveler) that will mount at the far ends (port and starboard) of my coamings. I've already modified the tiller so that it now pivots (vertically) inward of this traveler beam. The beam is mounted to two riser teak blocks (one on each end) and each of those blocks will mount to the coaming using two SS plates (one on each side of the coaming). So there are four stainless steel mounting plates all together.

I will be drilling the coamings to through-bolt the four plates. Each bolt would go through a plate, one wall of the coaming, another wall of the coaming and then the other plate before being fastened with a nut.

The port side of my cockpit does not have a lazarette. So I have cut an access port hole that allows me to reach the hollow area inside the port coaming. Actually, it turns out that these coamings are supported near their tops by what must be wooden beams which were fully glassed-in by O’Day. So those beams sit right beneath the top fiberglass skin of each coaming. Below that, however, the coamings are hollow. I want to fill the hollow far ends of each coaming (near the stern) where the plates will be bolted through.

I'd like to find a material that I can work into those hollow spaces (in each coaming) so that they end up solid fiberglass/epoxy/plastic etc. all the way through (from the stern end of each coaming in for about a foot or so towards the cabin). The challenge, and it is a big one, is that I need to stuff this material in primarily from below the cavity. So I'd need something that, in working form, is almost like clay but which dries to a solid and waterproof sort of plastic. I almost need a sort of slow kicking epoxy play-dough that can be molded into the space and then harden and bond.

On the starboard side I will be adding the material from below after crawling into the lazarette. So the challenge is the same.

Any ideas for what a good marine equivalent would be? I need something that would stay moldable for several minutes while I worked it in to fill the cavity.

 

[Stu Jackson]

Below that, however, the coamings are hollow. I want to fill the hollow far ends of each coaming (near the stern) where the plates will be bolted through.

Why?

 

[sreidvt]

It's a fair question. What I wanted to do was to make those areas solid fiberglass/epoxy so that I could through-bolt the plates. It would make those two mounting points quite strong. But I just got off the phone with a boat builder friend of mine and he thinks this would be very hard to do from below. So it looks like I will just use shorter bolts on each side and backing plates on the inside walls. Not quite as strong but likely strong enough.

 

[Stu Jackson]

I agree, why I asked. Good luck.

 

[sreidvt]

Thanks.

It would be easy to make the area a solid one if I was working from above into a void. But working from below in a tight space...

Mounting the teak risers with just backing plates should be quite simple.

 

[DrJudyB]

It would be easier to offer relevant advice if you posted a picture. I’m not confident that my advice is applicable without seeing a pic, but here goes:

have you considered putting a compression strut between the two walls of the coaming, as an alternative to filling the hollow with solid putty?

 

[sreidvt]

It would be easier to offer relevant advice if you posted a picture. I’m not confident that my advice is applicable without seeing a pic, but here goes:

have you considered putting a compression strut between the two walls of the coaming, as an alternative to filling the hollow with solid putty?

Hi Judy,

Thanks for the reply. That's a interesting idea but what I've decided to do (rather than through-bolt the lower connections) is to use shorter bolts and come in from each side wall of the coaming with a backing plate, washers and nuts on each inside wall. So the lower two bolts on each external SS plate will only run through a single wall of the coaming. The top bolt will run through the factory beam which runs just under the top skin of the coaming.

It helps the fiberglass coaming walls are about 1/4" thick so they seem pretty stout.

Appreciate your taking the time to reply.

Cheers,

 

[Brian S]

Hi Judy,

Thanks for the reply. That's a interesting idea but what I've decided to do (rather than through-bolt the lower connections) is to use shorter bolts and come in from each side wall of the coaming with a backing plate, washers and nuts on each inside wall. So the lower two bolts on each external SS plate will only run through a single wall of the coaming. The top bolt will run through the factory beam which runs just under the top skin of the coaming.

It helps the fiberglass coaming walls are about 1/4" thick so they seem pretty stout.

Appreciate your taking the time to reply.

Cheers,

Sreidvt, I think you could fasten your inner backing plates to the fiberglass with some epoxy slurry. Like, microfibers and colloidal silica mixed in with epoxy.

Please post pictures of your process, as I have been thinking about a custom raised bridgework traveler across the back of my 192 for some time now. I have not done it because I use the swim ladder a lot, and I figured it would make it more difficult to climb back in. Also, I wonder how much travel end boom sheeting will actually get going behind the boom on the coaming like that. The most effective traveler mod was Joe Alves' shaped traveler going across the cockpit of his 222, and I think moving to mid-boom sheeting. This is a total non-starter for me, because it would mean the end of cockpit seat napping!

 

[sreidvt]

Hi Brian,

Sorry for the delayed reply. I am only on the forum once in awhile and just saw this. I am at the point of Cetol’ing the traveler beam but need to wait for this heat to ease up. I have three coats left to do. Then it just a matter of bolting and bedding. The holes in the coaming are all done and the beam is all drilled, countersunk, etc. The top one on each side runs through solid fiberglass and the lower holes on each side are running through fairly thick fiberglass.

The teak support beam runs across the rearmost sections of the coaming on each side. It sits on contoured teak riser blocks to leave room for the tiller extender. The extender is hard bolted to the rudder so that the (now shortened) tiller can pivot just forward of the traveler beam. I stole the curved tiller from another boat of mine.

The teak beam is angle cut along most of its upper front edge to create a 55 degree angled face which the 4 foot traveler beam mounts on. That should be about the right angle for the mainsheet coming off the block towards the end of the boom (so that the traveler car pull angle is correct). I did a lot of measuring to determine that angle but it should be close to right.

With the four foot traveler I have adjustment across most of the cockpit width.

I will post pictures when I have some.

Cheers,

 

[MikeHoncho]

Utilize the most appropriate West Marine thickener for the epoxy and add it until you get thre consistency you ate looking for. I recommend getting to that point and letting it sit for a minute. You will probably find you will need to add more thickener.

 

[sreidvt]

Hi Again Brian,

In a perfect world that traveler might run across the seats near the end of the boom and just ahead of the tiller. My Mirage is set up that way and, while it works well, guests sometimes trip on the beam.But I think the coaming end location might work pretty well. We’ll see. I like end boom sheeting and, while this is not perfectly at the end it should provide much better sail control than the stock setup.

Regarding the swim ladder... Does your boat have a pushpit? If yes, do people normally crawl over the transom and under the stern rail? My boat has a pushpit and I am going to mount my swim ladder on the starboard side of the transom. When that is in use, my plan is to unhook the starboard lifeline ahead of the pushpit and have swimmers come around it on the starboard side and then into the cockpit.

With no pushpit I imagine that a stern traveler could make things a bit trickier for boarding from the swim ladder.

Added later: I do not know the 192 very well but I imagine a pushpit might not be common on them. So maybe the traveler beam would be a challenge with the swim ladder.

 

[sreidvt]

Utilize the most appropriate West Marine thickener for the epoxy and add it until you get thre consistency you ate looking for. I recommend getting to that point and letting it sit for a minute. You will probably find you will need to add more thickener.

Thanks Mike. I have decided, as posted above, that I do not need to fill them but I appreciate the suggestion. I recently did some filling on a smaller boat and this worked quite well: https://www.pcepoxy.com/products/permanent-repair/pc-11-paste-epoxy/

It is nearly as thick as peanut butter.

 

[Brian S]

Hi Again Brian,
Regarding the swim ladder... Does your boat have a stern pulpit? If yes, do people normally crawl over the transom and under the stern rail? My boat has a stern pulpit and I am going to mount my swim ladder on the starboard side of the transom. When that is in use, my plan is to unhook the starboard lifeline ahead of the stern pulpit and have swimmers come around the stern pulpit on the starboard side and then into the cockpit.

With no stern pulpit I imagine that a stern traveler could make things a bit trickier for boarding from the swim ladder.

Added later: I do not know the 192 very well but I imagine a stern pulpit might not be common on them. So maybe the traveler beam would be a challenge with the swim ladder.

Nope, no pushpit on my boat. Other little boats like the Precision 18 or 21 do have pushpits. I just have these SS handles on the sides mainly to hold the lifelines, I guess. Hooking up the Magma grill to these handles is a bit awkward, but I make do ok.

 

[sreidvt]

So having a rail there might make things harder for swimmers. I am trying to think of workarounds but nothing has come to me yet. Your boat looks like it is in great shape.