penetrating epoxies, solvents, foam core

[Muaddib1116]

I am in the middle of an arduous deck maintenance project. Essentially, my teak decks were glued down at the factory using clamping screws in the seams. After the screws were removed, they didn't fill the holes, they just caulked the seams to seal them. Now, after previous owners have sanded the decks a lot, the holes are getting exposed. There has been some water intrusion into my cored decks, which are foam cored. As far as I can tell there hasn't been any delamination, or at least not noticeable delam.

I am in the process of exposing all the holes by carefully removing sections of caulking. I would like to use some sort of thin epoxy in a syringe to fill each (very small) hole, and then butter in a dab of brown TDS epoxy to cap off each hole. My thought was to use some Total Boat penetrating epoxy. My concern is that the high solvent content in the penetrating epoxy will either damage the foam core and/or cause further delamination. I would just use normal epoxy, but I need it to be thin enough to put in a syringe and also to flow down into the deck core.

[Chotu]

epoxy comes in many different viscosities. If you search for an infusion epoxy it will drip right down in.

Just get a hold of one of the manufacturers. Maybe like Raka. They have good prices and the epoxy is just fine.

My boat is made from MAS infusion epoxy.

but basically ask some manufacturers which one you should get that is the thinnest. It will do what you want.

I would definitely forget about solvents like you are planning to forget about them. Because they are not going to have anywhere to go either. They will be unable to evaporate out of there. That could cause a problem in the laminate. Much worse than water.

[Muaddib1116]

I meant more about the solvents in the epoxy resins. My understanding is that all resins and hardeners have some sort of solvent content, and penetrating epoxies, even high solids ones, have much higher solvent/resin-ingredient percents. That being said, the MAS Low Viscosity Epoxy and Composite Envisions Infusion Epoxy both have much lower solvent content than say Total Boat Penetrating Epoxy.

My biggest requirement is really being able to squeeze it through a fine tipped syringe. From your use of the MAS epoxy, do you think it is thin enough to do so?

[Chotu]

Originally Posted by Muaddib1116

I meant more about the solvents in the epoxy resins. My understanding is that all resins and hardeners have some sort of solvent content, and penetrating epoxies, even high solids ones, have much higher solvent/resin-ingredient percents. That being said, the MAS Low Viscosity Epoxy and Composite Envisions Infusion Epoxy both have much lower solvent content than say Total Boat Penetrating Epoxy.

My biggest requirement is really being able to squeeze it through a fine tipped syringe. From your use of the MAS epoxy, do you think it is thin enough to do so?

yes. I understood what you meant. Sorry if I wasn’t clear. I meant the high solvent epoxy. Like total boat. That is not so great.

you could definitely squeeze low viscosity MAS epoxy through a syringe. it’s like water.

And about the product, it’s not what you are thinking. It’s not just a bunch of solvents. In fact there are no solvents. Check it out. Here is a little blurb about it.

if you think about it, you can’t have solvents in an infusion. They are also airtight just like your deck. So it has to be 100% reactive solids like they say below.


MAS Low Viscosity Epoxy Resin is a blend of standard low molecular weight epoxy resin and reactive diluents. Formulations based on MAS Low Viscosity Epoxy Resin are typically cured at room temperatures using MAS hardener in a 2:1 mix ratio, resin: hardener. MAS Low Viscosity Epoxy Resin can be used in a wide variety of applications including moisture exclusive coatings, laminating, and bonding. When modified with MAS fillers mixed formula can be used as a filling and fairing compound. This resin boasts a 600 cps viscosity. The reduced viscosity of MAS Epoxy Resin provides for complete wet out of fiber reinforced fabrics and reduces the potential for voids and other imperfections. MAS Low Viscosity Epoxy Resin is formulated from 100% low molecular weight reactive solids (for excellent moisture exclusion), and displays less than 1% shrinkage when cured. STORAGE LIFE: MAS Low Viscosity Epoxy Resin is specifically formulated for use and storage in adverse conditions. A non-crystalling formula allows the resin to remain clear and flow at very low temperatures. MAS Epoxy Resin will last a minimum of 12 months in a sealed container. Experience has shown the shelf life in most circumstances to exceed two years.

[Muaddib1116]

Oh that's great! I was assuming any sort of diluent was solvent based. I'll do some more research and compare some more epoxy SDS's. Thanks!

[Lepke]

I use un-thinned West System epoxy in syringes all the time w/o problems. Most places selling epoxy have thinners.

[Muaddib1116]

I couldn't find a thinner on their website. This makes me assume that you'd have to use some sort of solvent to thin their epoxy?

[rslifkin]

I've also used West in syringes. As long as it's not too cold it flows well enough to fill a hole and seep into any gaps a bit.

[Muaddib1116]

Sounds good, thanks guys!

[Searles]

Have used West Epoxy to fill exactly the same holes in the seams between deck planks ,carefull use of a heat gun will run the west into the near invisible holes ,it works ,have done it a lot .⚓️⛵️

[Muaddib1116]

Wonderful, thanks! Do you use the heatgun to warm up the deck? or on the epoxy in the syringe? I imagine I would want to use the slow or extra slow hardener.

[Bill O]

Can make a thinned epoxy like get rot with 1-2% acetone. It will take longer to kick though after you thin it w/acetone.

Could also use a low viscosity epoxy which contain no solvents like this one (Low V). https://epoxyproducts.com/1_marineresins.html

[JBP]

I frequently use a syringe for moderately thickened epoxy. Add long as the mix runs a bit it goes through the syringe just fine. These are glue syringes, not medical syringes.

[s/v Jedi]

Guys, this foam is designed to be used with epoxy; worries about solvents in epoxies is walking the wrong path.

Here is my recommendation: after opening up all these holes, use a slightly larger drill bit on all of them. If any wetness comes out, inject some denatured alcohol, which will take the water out while evaporating. Promote evaporation with a heat gun.

Before filling, blow the hole out with compressed air, or use a vacuum (make an attachment from a syringe without plunger). Then use unthickened epoxy (West System, MAS, Total Boat will all do fine but you don’t need penetrating epoxy when there is no delamination) with a syringe, making sure to put the spout all the way into the hole when filling it. Try to fill from the bottom up. Next, stir with cocktail pick and top up epoxy if needed.

[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.