I used the Six10 epoxy to bond replacement foil wing inserts into the carbon fuselage of an AFS foil. Ran into two problems, 1) apparently I did not rinse off all of the muriatic acid used to etch the inserts and overtime epoxy on the surface around the inserts turned brownish like the inserts were rusting, but they were not, A4 SS. So muriatic acid vapors must have collected on the lip of two out of three inserts and did not get rinsed off, inserts were put in hot water for 15 min. but water may not of gotten all the way up to lips; 2) some of the cured epoxy on the surface of the wing saddle turned white and was soft, scraped it off, was just excess, but when I called in to West Systems (great support) they said the epoxy was exposed to water too soon, need to wait 48 hrs, but I had waited 50 hrs in 77 degrees, so well over the recommended 72 degrees. BUT the directions say nothing about waiting 48 hrs for water exposure!, only to wait 24 hr before a load is applied. The good news is the epoxy issues were just on the wing saddle surface and under the insert lip in some areas on two inserts, so inserts are solid even after hitting sea-life and the bay sandy bottom.

Lastly, Six10 comes in a caulk style tube, and the opening for resin and hardener are the same size, but resin gets pushed out in a 2:1 ratio to hardener. So with the supplied mixing tip it is mixed good and correctly, but if you need to mix a little by hand, need to know that the clear resin is 2x to the yellowish hardener.

So I had to remove the small amount of Six10 epoxy I used to reseal the insert lips (after I dug out the white and brown epoxy). Was told regular 2 part epoxy will bond to Six10, so went with 90 sec. setting epoxy, actually worked good, stayed where I put it without slowly flowing away like the slower setting 5 min. 2 part epoxy, perfect for foil scratch repairs!

Actually, I was using 1 hr setting 2 part epoxy to repair foil scratches and dings, 5 min. epoxy might be good too, 90 second epoxy does not give a lot of time, but epoxy does stay where you put it, so make tiny amounts for each repair, basically one drop of resin and hardener.

So the 90 sec. epoxy still cures in 24 hr, and the small patches I added around the insert lips were done yesterday at 4 pm, but got on the water today at 1 pm. Was worried the 90 sec.epoxy would turn soft and white like the Six10 did, so I rubbed a candle stick over the epoxy to waterproof it, no whitening after the session, will see.

Still no sign of the new epoxy whitening the next day, so the wax treatment seems to work.

But the Harbor Tools and Freight 90 sec. epoxy did not say it was waterproof, but looks like the Devcon 2-Ton waterproof epoxy I have been using for years to repair wings and fins. Well HTF 90 sec. epoxy got soft and was easy to remove after two sessions in salt water, so back to Devcon. Looked at Home Depot and Walmart for a 2 part waterproof epoxy, did not have one, only water resistant. So fortunately Amazon carries the Devcon epoxy, going with the 2 separate tubes this time instead of the dual syringe which was a pain to dispense and got resin/hardener on the outside using the little plastic cap to seal syringe.

Consider going to West System 105 resin with 205 hardner, it is proven in marine applications if used correctly
A couple tips for 100% success
-Measure mix rate very carefully in cup with volume measurements
-Never mix or apply after the sun goes down or on wet rainy day
-Best done mid- morning on a warm sunny day, ideally I reckon days above 24 celsius
-Regardless of how little you need mix a minimum volume of 30ML
-Stir vigorously for 3 minutes, then rest for another 2mins in cup before applying
-Cure in warm, dry, shaded area not in sun

My experience is if you follow these steps the resin will set rock hard and stay that way

Good preparation of area for application is also paramount

We don't need to start 10 page debate on this, if you want test this system, mix a batch as detailed, pour on to plastic lid, let cure for 5 days, remove off lid then submerge in salt water for a couple of days and then hit with hammer

If this all sounds too hard, feel free to ignore

Cheers
Rod

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Freeflight said..

Consider going to West System 105 resin with 205 hardner, it is proven in marine applications if used correctly
A couple tips for 100% success
-Measure mix rate very carefully in cup with volume measurements
-Never mix or apply after the sun goes down or on wet rainy day
-Best done mid- morning on a warm sunny day, ideally I reckon days above 24 celsius
-Regardless of how little you need mix a minimum volume of 30ML
-Stir vigorously for 3 minutes, then rest for another 2mins in cup before applying
-Cure in warm, dry, shaded area not in sun

My experience is if you follow these steps the resin will set rock hard and stay that way

Good preparation of area for application is also paramount

We don't need to start 10 page debate on this, if you want test this system, mix a batch as detailed, pour on to plastic lid, let cure for 5 days, remove off lid then submerge in salt water for a couple of days and then hit with hammer

If this all sounds too hard, feel free to ignore

Cheers
Rod

Thanks Rod for the detailed information, will keep for when I have a big job. Right now the old Devcon 2 Ton epoxy is setting up good and sealing some small areas around the inserts, probably mixed 1/2 mL and used 1/10 mL.

So next time I use Six10 will let it cure for at least 5 days before exposing to salt water, West Systems tech support said full cure to get the last couple percent of polymerization takes 10 days.

Select to expand quote

Sandman1221 said..
So next time I use Six10 will let it cure for at least 5 days before exposing to salt water, West Systems tech support said full cure to get the last couple percent of polymerization takes 10 days.

The Devcon 2 Ton epoxy sealed up some small gaps around two inserts in the fuselage, where I removed water damaged Six10, after 48 hrs Devcon was exposed to saltwater for 2-3 hours and was waterproof. Want a nice epoxy seal around the inserts so if they ever move, from an impact, I will see a crack and know I need to do something fast. Did not want to wait 5 days or longer for Six10 to cure to waterproof, since really only cosmetic, but Devcon is strong just not as impact resistant as Six10.