My First Canoe Build

[Cruiser]

The idea is to mix up the epoxy, use the unthickened to wet the area a bit, then add your thickeners until you get a creamy peanut butter consistency, apply that and work in with a putty knife. If you can add sawdust to glue and get it thicker, then epoxy is no different ... just add a little at a time, then mix, until you get the consistency you want. You are looking for it to stay in the crack/hole ... so it doesn't need to be too thick.

You are only using the fillers as a colouring agent basically, if you think of then the same as the wood flour/dust ... it might seem easier. So the wood dust gets you the wood colour, the silica lets you lighten the mix a bit, so it's colour as well ... there are no real tricks to using it.

As an alternative, you could just thicken some glue, I personally don't like doing that as it never seems to wet out right (colour wise) but that could be me.

One other method I have been using with thickened epoxy, is to do all the finish sanding and cleanup ready to epoxy. Then tape around the cracks (idea is to leave just the area to be filled) the day before you plan to do the FG/epoxy ... wet out and fill the cracks as mentioned above, do a careful wipe with a cloth soaked on mineral spirits to remove any epoxy that gets on the strips.

Then lay out the glass and do the layup. The filled areas will just bound to the new epoxy glass the layup itself will make the filled area level and you don't need to do any sanding or treatment of the filled area.

Brian

 

[Cruiser]

One thing about solo glassing, avoid it at all costs if you can.

You don't need experienced people to help, the extra hands are what helps, if you have some one watching the time and mixing you epoxy, it means you can take care of getting the glassing done. There is enough pressure getting a feel for the process, worrying about the glass kicking ... without doing that and worry about timers and dispensing/mixing ... the extra hands are invaluable.

Second thing, setup up an epoxy station that is clean and clear, just to dispense and mix the epoxy. Clean the shop so all obstacles are removed and you have clear walkways to move around the canoe.

Basically, make your life easier by planning the epoxy operation, organizing the mixing station and making sure you can move around easily. Once you get under the application "gun" you don't have time for dancing IMO.

Brian

 

[dcloots]

One thing about solo glassing, avoid it at all costs if you can.

You don't need experienced people to help, the extra hands are what helps, if you have some one watching the time and mixing you epoxy, it means you can take care of getting the glassing done. There is enough pressure getting a feel for the process, worrying about the glass kicking ... without doing that and worry about timers and dispensing/mixing ... the extra hands are invaluable.

Second thing, setup up an epoxy station that is clean and clear, just to dispense and mix the epoxy. Clean the shop so all obstacles are removed and you have clear walkways to move around the canoe.

Basically, make your life easier by planning the epoxy operation, organizing the mixing station and making sure you can move around easily. Once you get under the application "gun" you don't have time for dancing IMO.

Brian

I will be hiring the help of my son Camden. He has shown much interest in building the next canoe with me so this will be an important step that he can assist with. I am thrilled to learn that he has so much interest in building the next canoe together. I have to admit, I am surprised due to the fact that most kids these days do not want to do such things. He will be the epoxy mixer and the timer. Today I will be ordering the fumed silica and because my son will be mixing the epoxy I will be also purchasing the metered pumps for the 3:1 ratio to eliminate any miscalculations . How much silica do I order though? If the silica is anything like the cedar flour then it will take a decent amount to thicken to the proper consistency.

 

[dcloots]

Answered my own question with the fumed silica to epoxy ration. US Composites website explains that well.

 

[alsg]

I think West sells fumed silica in like 1.7 oz, 5.5 oz and 10 lb(!) quantities. You definitely don't need 10 lbs. It is more efficient in thickening epoxy than cedar flour, but if you are building two canoes, you might as well get the 5.5 oz size.

Also, make darn sure you and your son wear a good quality mask/respirator when working with fumed silica. Fumed silica is notorious for easily getting airborne and you don't want to inhale it. Uncured epoxy (fumes and sanding dust) ain't great for you, either. For that matter, neither is cedar sanding dust.

 

[Jim Dodd]

I think West sells fumed silica in like 1.7 oz, 5.5 oz and 10 lb(!) quantities. You definitely don't need 10 lbs. It is more efficient in thickening epoxy than cedar flour, but if you are building two canoes, you might as well get the 5.5 oz size.

Also, make darn sure you and your son wear a good quality mask/respirator when working with fumed silica. Fumed silica is notorious for easily getting airborne and you don't want to inhale it. Uncured epoxy (fumes and sanding dust) ain't great for you, either. For that matter, neither is cedar sanding dust.

Spot on great advise !

 

[Cruiser]

Just one thing DC about thickening the epoxy, don't try and get it done in a single measure ... sneak up on it a bit. Add a bit, mix it, add a bit , mix it .... you will quickly get a feel for it, but it is always easier to add a bit more than repump and redo the batch. This also fits nicely with the idea of controlling the colour, as you sneak up, you lighten or darken the mix by what you add.

If you decide to try filling just prior to glassing, to avoid having to sand it all ... once you have the voids filled and wiped, you have several hours to get the glassing started, as long as your epoxy recoat schedule.

Unless you have some large voids to fill, a little bit goes a fair ways, I order it a quart at a time, not sure what that translates to weight wise.


Brian

 

[dcloots]

I think West sells fumed silica in like 1.7 oz, 5.5 oz and 10 lb(!) quantities. You definitely don't need 10 lbs. It is more efficient in thickening epoxy than cedar flour, but if you are building two canoes, you might as well get the 5.5 oz size.

Also, make darn sure you and your son wear a good quality mask/respirator when working with fumed silica. Fumed silica is notorious for easily getting airborne and you don't want to inhale it. Uncured epoxy (fumes and sanding dust) ain't great for you, either. For that matter, neither is cedar sanding dust.

Oh yes, I have an old friend from Maine Maritime Academy that works with fiberglass daily. He wishes that he had taken necessary precautions in the past and has since warned me of the dangers of working with epoxy. I have ordered 3M masks that will do the trick per his recommendation. Appreciate all the advice from this board. Someday I hope to share with others what I have learned from all of you and what I have learned from my mistakes. Thank you to all.

Also just ordered the fumed silica and metered pumps for the epoxy. With my sons assist it will be helpful to have the metered pumps for maximum accuracy with the resin/hardner mix. With plenty of cedar flour on hand I will soon have all the ingredients to fill the small gaps and fair a few small areas that dimpled. You can see the dimpling on one of my last photos (left hand of photo near the bow). The glue came undone and is actually loose. I plan on installing a vertical strongback to tie these two strips back together and then epoxy the strips on each side of the strongback to secure this dimpling. I will then remove the strongback and then fair the area where the strongback was attached. Hoping this is a suitable method.

 

[dcloots]

New Video uploaded. Part 6, Fairing the hull. Sanding, block planing and filling the gaps and loose knots with a 3:1 epoxy ratio. Used graduated cups for the thickened epoxy as I have not received my metered pumps from US Composites yet. Also, I couldn't wait for the shipment of the fumed silica from US Composites so I went to West Marine and picked up the Colloidal Silica which is the same as Cabosil. Hope to receive the pumps soon for maxiumum accuracy during the fiberglass wetout. Next step or next video will be laying the fiberglass on the exterior of the hull in preparation for repeated steps on the interior of the canoe. As much as I wanted to follow the recommendations of filling and laying fiberglass in the same evolution I just could not make that happen. Initially I was sanding without the dry vac connected to the orbital. Well...I realized how much of a mess that made. What a difference utilizing the dry vac. Night and day! 3M Mask is also being delivered and I will need to wait on this and additional nitrile gloves prior to proceeding with sanding the fill coat. Anyway, decent progress. I received a comment on Youtube about wetting the entire hull with an epoxy coat. It makes sense to me and I did read this in Gil's book. What is everyone elses opinion on wetting out the hull? Again, it makes sense to me, but will in fact add weight.

https://youtu.be/4apZVXXfS54

 

[Alan Gage]

You should be good with the Cabosil. When I started I always bought microballoons thinking it was the same thing. It seemed no matter how thick I mixed I would constantly run into sagging issues when filling a large gap or attaching gunwales to the hull. Then one day I came across an article or blurb or something that mentioned Cabosil won't sag where microballoons willl. So I got some Cabosil and lo and behold they were correct! No more sagging.

For filling holes/cracks I mix it up thick and apply with a squeegee (plastic, not rubber). I can use the squeegee to press it into the gap and then wipe off the excess so there's very little to sand.

Fiberglass always seems to be the most intimidating part for first time builders but it's not a big deal. Just keep moving and don't be afraid to dump your cup and mix up fresh. Once you feel the cup start to warm up stop using it. It can go from liquid to goop in a VERY short period of time once it starts to kick. And if you put goop on the hull it's going to stay goop and at best will require a lot of sanding. At worst it won't fully saturate the cloth.

You'll get more working time if you pour the mixed epoxy into something shallow and flat (like a rolling pan) instead of leaving it in the mixing cup. The hotter it is the faster it kicks and as it starts to kick it generates its own heat which makes it kick faster, which generates more heat which makes it kick faster......

In a large shallow tray it can better dissipate heat to slow itself down a little.

If you're using rollers it's not a bad idea to swap them out at least once. Sometimes the epoxy that's trapped in the roller will start to kick.

I like to pour resin directly onto the bottom of the hull and spread it with a squeegee. For the vertical sides I switch to a roller. This is the quickest way for me to do it. I put it on fairly heavy so that there is plenty to soak into the wood and cloth. When the canoe is about half way done I go back with a squeegee to remove the excess before finished the 2nd half.

Alan

 

[dcloots]

You should be good with the Cabosil. When I started I always bought microballoons thinking it was the same thing. It seemed no matter how thick I mixed I would constantly run into sagging issues when filling a large gap or attaching gunwales to the hull. Then one day I came across an article or blurb or something that mentioned Cabosil won't sag where microballoons willl. So I got some Cabosil and lo and behold they were correct! No more sagging.

For filling holes/cracks I mix it up thick and apply with a squeegee (plastic, not rubber). I can use the squeegee to press it into the gap and then wipe off the excess so there's very little to sand.

Fiberglass always seems to be the most intimidating part for first time builders but it's not a big deal. Just keep moving and don't be afraid to dump your cup and mix up fresh. Once you feel the cup start to warm up stop using it. It can go from liquid to goop in a VERY short period of time once it starts to kick. And if you put goop on the hull it's going to stay goop and at best will require a lot of sanding. At worst it won't fully saturate the cloth.

You'll get more working time if you pour the mixed epoxy into something shallow and flat (like a rolling pan) instead of leaving it in the mixing cup. The hotter it is the faster it kicks and as it starts to kick it generates its own heat which makes it kick faster, which generates more heat which makes it kick faster......

In a large shallow tray it can better dissipate heat to slow itself down a little.

If you're using rollers it's not a bad idea to swap them out at least once. Sometimes the epoxy that's trapped in the roller will start to kick.

I like to pour resin directly onto the bottom of the hull and spread it with a squeegee. For the vertical sides I switch to a roller. This is the quickest way for me to do it. I put it on fairly heavy so that there is plenty to soak into the wood and cloth. When the canoe is about half way done I go back with a squeegee to remove the excess before finished the 2nd half.

Alan

Thanks for the advice. The epoxy did kick on me a couple times with just the small batches. At least I know now what I am looking to avoid. I guess I should have been more clear about what I meant by wetting the hull.....what I should have said was “wetting the hull with a seal coat prior to laying fiberglass”. So essentially it would be the fill coat, which I have already done, then sand, then followed by the seal coat prior to laying the fiberglass. Gil does talk about seal coating. Thoughts on my clarification as I think I may have led people astray with my last post.

 

[alsg]

Gil recommends doing this so the cedar won't suck up epoxy during glassing resulting in starved fiberglass.

 

[dcloots]

Gil recommends doing this so the cedar won't suck up epoxy during glassing resulting in starved fiberglass.

Alsg, did you practice this method on your Wabnaki?

 

[Alan Gage]

Sorry, I was playing catch-up and I just skimmed your last post. I missed that you'd already filled your cracks.

As for the full seal coat: I skip it. Others wouldn't think of skipping it. My boats haven't sank and there's don't really weigh any more. Take your pick.

To me it's just one more step that I can live without.

Alan

 

[alsg]

Alsg, did you practice this method on your Wabnaki?

I did.

 

[memaquay]

I've done it both ways, but now I don't bother with a pre-coat. Just do a good job on the wet out, let it sink in and squeegie.

 

[Cruiser]

The cedar will drink what the cedar will drink, IMO the fill coat is just extra work, more steps more sanding and more epoxy. I don't do it and have not heard anything compelling enough to make me try it.

If you follow the normal regimen of 3 coats to bed the epoxy, and do those all in one day to get chemical bonds between the layers for maximum strength ... plus the initial coat is adhered "into" the wood directly.
If you precoat, the initial coat forms the wood bond and when it sets and you sand it, the initial coat of epoxy with the fiberglass can only form a mechanical bond to the pre-coat.

So at the end, if you pre-coat, there are 4 epoxy layers and 2 sanding operations ... if you just use a normal 3 coat regime you should have better bonding and less work.

Brian

 

[Cruiser]

As far as the epoxy kicking, the reaction starts as soon as you catalyze, and it's an exothermic reaction which helps the resin polymerize ... if you let it get hot it kicks hard and fast.

When you are mixing the larger batches you are going to need for fiber glassing, it is important to get the catalyzed resin spread out ... either in a tray or on the boat surface as fast as you can. this allows the heat to escape and not build up, giving you more time to work and the epoxy more time to spread evenly. The larger batches will be generating more heat simply because a larger volume generates more and it retains the heat better ... so mix it well and get it spread fast, the initial spread doesn't need to be pretty, but does need to get done quickly ... you then have time to go back and move it around some.

If you have any interest, BearMountain has a whole builders series of videos that I feel have a lot of good info, you may change up stuff, but they give you a good idea of what expect and good tips on how to do it. https://www.youtube.com/watch?v=suefRmBfrwg&list=PLU4oSXwGGGSL7ROt9pFu5VQg2WylhJbSs&index=17

Brian

 

[Jim Dodd]

Wish I was there to help glass the hull. !

Mix no bigger than 9 oz batches at a time.
I like Cigar type rollers, I struggle with Squeegees and the epoxy ends up on the floor, most of the time !

Once you have the cloth wetted out the first time, don't walk away from it ( Going out to eat) as air bubbles, or problems Will pop up ! Have a hair drier handy, and warm the bubbles that pop up, then brush with a foam brush.

Getting back to Dust masks !
3M's Cartridge type is what I use ! The next step up is a Hood type, with a battery pack and filter attached to your belt

https://www.googleadservices.com/pa...iHkPDi1o7oAhWPWc0KHf4yB5IQ9aACegQIDRB1&adurl=

Good Luck !

Jim

 

[stripperguy]

Count me as one of the "others"...I always apply a seal coat before the glass and wet out. I mostly use RAKA resin, and IIRC, there was a statement that you'll still get a chemical bond as long as you're within 72 hours from the last application. FWIW, I've never had a delamination with epoxy resin, and I've damaged quite a few hulls.

After my seal coat, I lightly sand the hull to knock off any dust burrs.
Just before laying on the cloth, I also sand my hands with some 220 grit, I always have cuts and snags on my hands and this helps prevent pulls on the cloth as I'm smoothing things out.
And yes, if I'm using an extra 1/2 layer, I wet that out at the same time as the full layer. I put the 1/2 layer under the full layer, others put the 1/2 layer on the outside.

Like Alan, I pour my mixed resin directly on the flatter parts of the hull and work it around with a squeegee. And before everything is kicked, I squeegee again to remove any entrained air and force the glass down as close as possible to the wood. I get better strength and a more clear lamination that way.
If I was using a roller, I would keep the filled tray on the concrete floor to help keep the resin cool.
Also, I do not trust any metering pumps, I've seen much disparity between what I thought I measured and the actual quantity. A small error times 20 pumps quickly becomes significant. For larger quantities, I prefer graduated paint cups,. Be sure to thoroughly scrape the sides of any cups, any leftover resin or hardener will add to ratio disparities. For small quantities, I used graduated syringes, I think each one holds a maximum of 2 oz.

That's al I can think of for now...wait! I don't remember if you've already purchased your resin, but if not, buy a SLOW hardener, it will keep your blood pressure lower.