penetrating epoxies, solvents, foam core

[s/v Jedi]

Originally Posted by Muaddib1116

Thanks for the additional suggestions! I'd really like to avoid opening the holes up wider. I am thinking that I could use a 16 or 18 gauge needle to fit in the holes and get down well into the deck core. These have ID's a little below and a little above a millimeter. I'll have to experiment with if these will accept epoxy. Thanks.

Why the hesitation to enlarge the holes? You really need to clean them up or the epoxy will not adhere and you will get leaks again.

[Muaddib1116]

The holes are at the edges of each plank going diagonally into the deck. They are left over from clamping screws during the initial teak deck glue down. They were never filled, just covered by caulking. The previous owners had sanded the decks enough that they are starting to be exposed/unsealed. The decks are due for a light maintenance sand (I think quite different than what the previous owners had been doing), and I would like to minimize the size of all these expoxy dots on the deck as the deck is sanded every few years. If I can use a 16 or 18 gauge needle to get epoxy down in to the deck core, and then fill the hole in the teak with TDS brown epoxy (which I'm told greys like teak does), then I don't really see the need to enlarge the holes.

[Searles]

Opening the fastening holes up a bit is a good idea ,although we have never done this ,warming the deck up to easy touch temperature will help,just a bod of epoxy on the hole then lightly warm the epoxy as it thins with the heat and runs into the gap just add a little more ,never tried to heat the epoxy in the syringe .⚓️⛵️

[Muaddib1116]

I'll buy a variety pack of syringe tips and see what fits. If I can inject epoxy, normal west systems or one of the good low viscosity ones directly into the core without depending on gravity, I think that eliminate the need for excess heating or drilling out. Assuming all that works, I think the trickiest part will be adding a dab of the brown TDS epoxy at the top of each hole. Maybe the thing to do is experiment and see if I can use that brown epoxy in a syringe, although I have a feeling it is sort of on the opposite ends of things than a penetrating epoxy.

[s/v Jedi]

I’m sorry, I don’t get it. You write that the clamp down screws were in between the planks but then you also write that there are holes in the teak planks that you want to fill?

No, don’t use epoxy above the fiberglas! Only use epoxy for the core and up to the fiberglass skin. There should be no epoxy above that level. And you really must clean that hole. You don’t need the needles of the syringes, you can get special epoxy syringes that have a spout.

If the screws went through a teak plank then you must use a teak plug to close the hole. Drill it out to the size of the plug, then insert it with some glue.

If the screws were in between the planks then you must use caulk there. I think you wrote that they used caulk after removing the screws, which is the correct way, but they didn’t fill the holes in the fiberglass and this is what needs to be done before caulking up between the planks.

I can see how some planks got damaged but then that would have been from new, not from this work?

[s/v Jedi]

Apparently they are dental syringes, with all kinds of spout shapes.
https://www.amazon.com/TecUnite-Disp.../dp/B078K8SVMN

[Muaddib1116]

When they glued the deck down, the clamping screws were in the seams. It looks like they were put in at an angle, at the edge of each plank. So when the plank was full thickness, the start of the hole was along the side of the plank, in the caulking seam. But as the deck has been sanded down over the past 20 years, (It looks like one or more previous owners had the yard do a fresh sand every couple years or something, far too frequent) the holes that were well buried in the caulking seems have become exposed. The hole goes through the edge of the teak plank (at an angle) and down into the foam core. I appreciate your advice, but I am not going to drill out and bung a thousand tiny holes that could just be filled with a bit of brown epoxy. The teak decks themselves are glued down with epoxy, what does it matter if a bunch of little holes in the teak above the fiberglass skin have some epoxy in them?

[s/v Jedi]

Originally Posted by Muaddib1116

When they glued the deck down, the clamping screws were in the seams. It looks like they were put in at an angle, at the edge of each plank. So when the plank was full thickness, the start of the hole was along the side of the plank, in the caulking seam. But as the deck has been sanded down over the past 20 years, (It looks like one or more previous owners had the yard do a fresh sand every couple years or something, far too frequent) the holes that were well buried in the caulking seems have become exposed. The hole goes through the edge of the teak plank (at an angle) and down into the foam core. I appreciate your advice, but I am not going to drill out and bung a thousand tiny holes that could just be filled with a bit of brown epoxy. The teak decks themselves are glued down with epoxy, what does it matter if a bunch of little holes in the teak above the fiberglass skin have some epoxy in them?

When you fill that with brown epoxy, then you fill the seam with epoxy too, right?

When you bring the epoxy to top of the teak level, you have ruined it. It will look like teak with brown epoxy dots all over, like if they filled screw holes with epoxy. Better rip it off and paint a nice antiskid.

[Muaddib1116]

Originally Posted by s/v Jedi

When you fill that with brown epoxy, then you fill the seam with epoxy too, right?

When you bring the epoxy to top of the teak level, you have ruined it. It will look like teak with brown epoxy dots all over, like if they filled screw holes with epoxy. Better rip it off and paint a nice antiskid.

My goal is to fill the holes with epoxy, and recaulk the seams where I've torn it out. I suppose it's a choice between lots of little dots and lots of bungs. One seems like a lot less work than the other. I'm not sure I'm ready to tear all the teak off yet, although maybe someday. I don't think that whatever I do now will make that option any more difficult.

[garyfdl]

My suggestion would be to contact Paul Oman, proprietor of Epoxy Products and put your question(s) to him. He is a wealth of knowledge and an excellent resource.

https://www.epoxyproducts.com/pep.html

if you are located in Boston, you could probably go up an meet him. IIRC he is in New Hampshire.

[s/v Jedi]

Originally Posted by Muaddib1116

My goal is to fill the holes with epoxy, and recaulk the seams where I've torn it out. I suppose it's a choice between lots of little dots and lots of bungs. One seems like a lot less work than the other. I'm not sure I'm ready to tear all the teak off yet, although maybe someday. I don't think that whatever I do now will make that option any more difficult.

The teak bungs will not be visible or at least look like they belong there. I think it’s quicker to glue those in than to fill with epoxy, but I guess you have to find out yourself like all who have done this had to find out.

Just know that you can buy the teak bungs ready made and a quick drill and glue in is much less work than filling with epoxy.

[Muaddib1116]

I guess I'll find out. An additional problem is that after bungs are glued in, I would have to chisel or router out the caulking groove again. I'm hoping I can avoid doing that with the epoxy.

[s/v Jedi]

Originally Posted by Muaddib1116

I guess I'll find out. An additional problem is that after bungs are glued in, I would have to chisel or router out the caulking groove again. I'm hoping I can avoid doing that with the epoxy.

Yes but that is only a couple seconds of work using a track saw. I think you need that with epoxy method too.

[Senojev]

A good inexpensive source for syringes and different size mating needles is your local Tractor Supply or Farm and Fleet store. Look in the animal medical section and you can get large bore needles.

[I14]

The reactive diluents in low viscosity epoxies have an epoxy group on one or both ends so they react with the amine hardener just as the primary epoxy does so are no longer fugitive. Non-reactive diluents were used for some time but they will stay trapped in the cured epoxy. If you use it in its clear form (no brown filler) it should not be visible when cured