Epoxy setting time

[KenStocker]

I am looking ahead to building the Tammie Norrie. Curious as to the average time it takes for most epoxies to set. I will most likely be setting planks by myself, first time using epoxy, and realize that there is some time involved getting a strake in exactly the right place while I can still make adjustments.

[StevenBauer]

It really depends on that epoxy you use. And which hardener you use with it. The slow hardeners will leave you with plenty of time to hang your plank.

[signalcharlie]

What temperature are you working in? Oregon summer temps you'll be okay with Slow hardener, winter time you might need Fast. You'll have 30+ minutes to move things around, I planked the P14 and scarfed by myself with no issues. Depends on how much you mix up at once as well, a big batch will kick off faster. Warmer temps kick off faster. If you pump resin and hardener for each batch, you might get a batch that hardens quick because of excess hardener and then another that takes a long time to final solid cure. If that is a concern you could buy 2 part systems in a tube, they dispense in a more consistent amount but cost mo dollah $$$.

West System

TotalBoat THIXO

[upchurchmr]

Using pumps to mix epoxy (West system) has always been consistent for me.
My shop temperatures in Texas are a lot higher than you have so no help from me there.

But the key to using epoxy is to fit everything together exactly as you want it, mark it so you can repeat the fit, then glue.
Not trying to adjust fit after you have mixed or applied the epoxy.

Another thing you might want to do is to clean up the squeeze out as soon as the plank is set, inside and out.
Epoxy can be infuriating to clean up drips and squeeze out when dry.

I would encourage you to to a test. Just take two scrap pieces of wood and try it. Well, maybe multiple sets.
That way you can pull one apart at 10 minutes, another at 20, etc.
Then you will know for your own temperature.

The other suggestion is to ask at the West system site. They try to be helpful.

[David G]

What temperature are you working in? Oregon summer temps you'll be okay with Slow hardener, winter time you might need Fast. You'll have 30+ minutes to move things around, I planked the P14 and scarfed by myself with no issues. Depends on how much you mix up at once as well, a big batch will kick off faster. Warmer temps kick off faster. If you pump resin and hardener for each batch, you might get a batch that hardens quick because of excess hardener and then another that takes a long time to final solid cure. If that is a concern you could buy 2 part systems in a tube, they dispense in a more consistent amount but cost mo dollah $$$.

West System

TotalBoat THIXO

I'll second the suggestion to dig into the lovely free 'how-to' info available. If you're going to be working with epoxy... I'd first read, then keep the "... On Boat Construction" resource bookmarked. This most excellent reference, they have now made available not just in hard copy... but as a free download. --

[DeniseO30]

fit fit fit, fit again. make sure. AND. learn how to mix the right fillers in the epoxy for good glue joints. ALSO you don't want runs and drips on all your nice planks. if the viscosity of your mix is right you will get very little drips and runs. I've almost never used "fast" hardeners in epoxy.

[the_gr8t_waldo]

formulations made by the manufacturer for different set times are fine, but changing the ratio of epoxy to catalyst should never be considered. .....shape/fit the piece to be glued so that there's no more to be done on that piece , time spent doing this will save you a lot of anguish later when you've mixed the epoxy. once you do mix the epoxy and catalyst- the clock is ticking! the larger the batch, the shorter the working time. so mix up what you need for that stage and be prepared to use it. also keep the work area, and material as cool as you can reasonably work in. ( this will probably take over night to stabilize everything to the new temperature.) once the part is glued, you can turn back up the thermostat for the work area. If your project requires that unthickend epoxy be applied first... mix only what you need for that stage, once mating surfaces are coated, then progress to the the thickened batch and apply.

[David G]

formulations made by the manufacturer for different set times are fine, but changing the ratio of epoxy to catalyst should never be considered. .....shape/fit the piece to be glued so that there's no more to be done on that piece , time spent doing this will save you a lot of anguish later when you've mixed the epoxy. once you do mix the epoxy and catalyst- the clock is ticking! the larger the batch, the shorter the working time. so mix up what you need for that stage and be prepared to use it. also keep the work area, and material as cool as you can reasonably work in. ( this will probably take over night to stabilize everything to the new temperature.) once the part is glued, you can turn back up the thermostat for the work area. If your project requires that unthickend epoxy be applied first... mix only what you need for that stage, once mating surfaces are coated, then progress to the the thickened batch and apply.

That's a mistake - and a serious/catastrophic one - that seems most commonly to spring from the polyester resin world, where changing the % of catalyst (MEKP) works just fine, and serves to modulate the speed of cure.

[KenStocker]

Thanks for all of your input, and I will definitely look into some of the materials suggested. I have a lot to learn!

[callsign222]

It took me a whole boat to learn to do it right between the working time, time to cure, consistency and thickness needed for different applications, techniques, etc. Two part 1:2 epoxies like System III, Duckworks DWX, are also a little more forgiving than the 1:5 epoxies in my experience-- some mix by volume some by weight but I've always had a bit of fudge factor with the 1:2 glues which is nice.

West Systems has some great primers here: http://www.westsystem.com/instruction-2/

The Olde You Tubes has tons of great videos-- like Red Barn Boats: https://www.youtube.com/user/redbarnboats/videos

A little practice first will save you $$$ and effort later.

[Gerarddm]

Dry fitting everything is first before gooping with epoxy. Also, since epoxy will slide the joint as pressure is applied, dry fitting allows you to set down markers or stop blocks so you can be assured the plank will stay affixed in the exact location you want as the epoxy sets.

I used WEST for my wherry, both fast and slow hardeners depending on temps. No problems.

[SMARTINSEN]

"Dry fitting everything is first before gooping with epoxy."

I think that it is implied by Gerard, but even go the extra step and take a practice run with all of the clamps. After all the work of achieving a perfect fit of your pieces, there is nothing worse than struggling with unwieldy epoxy slathered clamps. Or not having enough of them in the right places.

Depending on your finish, do not be afraid of sinking a temporary drywall screw to hold things in place. Just do not forget to remove it before complete cure.

[KenStocker]

"Dry fitting everything is first before gooping with epoxy."

I think that it is implied by Gerard, but even go the extra step and take a practice run with all of the clamps. After all the work of achieving a perfect fit of your pieces, there is nothing worse than struggling with unwieldy epoxy slathered clamps. Or not having enough of them in the right places.





Depending on your finish, do not be afraid of sinking a temporary drywall screw to hold things in place. Just do not forget to remove it before complete cure.

I am so on board with dry fitting things! Having done a lot of woodworking, I know how easy it is to make mistakes. (Measure twice, cut once is optimistic! I'd rather measure a dozen!)My plan is to go extremely slow, especially since I am launching out(so to speak!)into an area I haven't ever dealt with. Good advice, too, on setting up with markers or blocks so that when the epoxy is applied you have the baseline to go back to. I like that idea. Thank you all for the input, I am reading the download on the West System Epoxy. Looks very informational.

Ken