Epoxy Confusion!!

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JesseP
Posts: 46
Joined: Fri Apr 10, 2015 11:13 am
Location: East Central, AB

Epoxy Confusion!!

Post by JesseP » Thu Jun 25, 2015 10:17 pm

Alright guys, I would like to start by thanking everyone for their input so far.. it has really helped me get through some jams.

Now to the questions haha. Ok. I have finally received my epoxy kit and fiberglass in the mail and am anxious to get these outer stems glued in place. As I said before my Canoecraft has gone MIA and have been proceeding with online help and manufacturer instructions. My understanding is that I should use the 2 step wet bonding method to attach the outer stems. The Epoxy kit I received is WestSystems 105b Epoxy with 207b hardener. For this method I read that I am to do 1 full stroke of epoxy to 1 full stroke of hardener and this is to be applied to the inner stem and planking. Before the epoxy hardener mixture hardens I am suppose to mix a batch of thickened epoxy by again using a 1to1 ratio of hardener and epoxy mixed with (now this is where I get the confusion.) either WestSystems 403 or 410 one is a microfiber adhesive filler and the other is a fairing filler. I then mix in the filler until peanut butter like consistency and smear it on the outer stem and clamp\screw to the inner stem. Does this sound right?

Thanks guys/gals you have been a huge help so far!

Believe me I have more questions..... Just don't want to over load the thread.
I'm up to my torch.

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Patricks Dad
Posts: 1378
Joined: Wed Oct 13, 2004 1:11 pm
Location: Warrenville, Illinois

Re: Epoxy Confusion!!

Post by Patricks Dad » Fri Jun 26, 2015 8:28 am

1 full stroke of epoxy to 1 full stroke of hardener
Just to make sure we're on the same page, I'm assuming that you are using the West System pumps in your epoxy and hardener cans and you are referring to 1 full pump of each. If so that is correct. These pumps do not deliver the same volume for each stroke. They deliver the correct ratio (3.5 to 1 if I remember).

All of your epoxy mixing should use the same ratio and therefore the same number of pumps from each can.

Once you have thoroughly mixed that (I always stir for a full 2 minutes), you should brush it onto the surfaces you will be mating. The stems won't absorb as much as the end grain of the strips. Keep brushing the unthickened epoxy on to the strip ends until they will take no more. This could take 10-15 minutes or so.

Once you're satisfied that the strips won't take any more, you can then either:

1. Thicken the remaining epoxy you have left over from the above step (if you think there is enough) or
2. Mix up a new batch of epoxy (hardner and resin at the same ratios as above) and thicken it.

To thicken the epoxy mix the adhesive filler (I use carbosil - it's pure white, fluffy and dangerous - wear a mask) a bit at a time (with experience you'll know just how much to add but you can sneak up on it this time). Mix in some wood flour (i.e., sanding dust) to match the color of the wood you are mating. When in doubt make it a bit darker (it will be less visible than if you mis-match on the light side). The mixture should be the consistency of peanut butter.

Before you apply your peanut butter, take a rag and wipe off any remaining excess unthickened epoxy that is still on the surfaces of the stem or end grain of the strips.

slather the peanut butter on both sides of the joint and clamp. Clean-up squeeze-out with your finger or a squeege (by whatever means necessary). You will have plenty of working time so don't get nervous.

Exciting times.
Randy Pfeifer
(847) 341-0618
Randy.Pfeifer1@gmail.com

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Jim Dodd
Posts: 1178
Joined: Wed Feb 08, 2006 11:08 pm
Location: Iowa

Re: Epoxy Confusion!!

Post by Jim Dodd » Fri Jun 26, 2015 9:00 am

I agree with Randy ! Great method !
I will blend in a little wood flour, or very fine wood dust from my ROS collection container, to blend the color of the mix to the wood.

I use a different epoxy, and have always had trouble with pumps burping and giving incorrect ratios.
I prefer to use marked cups. But again I use a different resin.

Jim
Keep your paddle wet and your seat dry!

JesseP
Posts: 46
Joined: Fri Apr 10, 2015 11:13 am
Location: East Central, AB

Re: Epoxy Confusion!!

Post by JesseP » Fri Jun 26, 2015 9:13 am

Thank you!

Once again this forum has proved to be very helpful. Thanks for the quick responses to all my questions guys. I have some time this coming weekend and will be putting your advice to work and start making some progress on my canoe. Keep checking back as I will continue to post pictures and updates of my progress. Once again a huge thanks to all of you.

Jessep
I'm up to my torch.

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