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Thread: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

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    Default What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Will be a first timer when I fiberglass my 12 foot jon boat with West 105 epoxy. During my research, I heard that whatever epoxy applying materials to fiberglass one thinks is needed, double it. I have no clue what to double.

    What capacity mixing container is good for mixing resin when applying 6 oz fiberglass cloth? 32 ounce a good size? How many?
    I also need some smaller containers for measuring the resin and hardener as I think using the pumps will be too slow. What size for that?

    What diameter and length foam roller would you recommend for glassing a flat bottom 12 foot jon boat?
    How many rollers? I already bought an epoxy squeege and have some rubber squeeges from my Bondo auto repair days.

    And how many roller pan covers would you recommend?

    Anything else?

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Hmm. 12 feet is not all that big, I don't think you need to overthink it. I've used left over plastic takeout containers that are ~16oz for most things and they seem to be fine (measure by weight, so the container you use doesn't matter). You can also usually re-use the containers -- once the epoxy has cured, flex the container and it should come out in a single layer (some plastic containers are more resilient to this than others). Ideally you have the right hardener so you aren't in a terrible rush and don't have to have premixed everything (in which case, you only need _one_ container per session!), but if you'd rather do that, then estimate how much glass, use the ratio for epoxy to glass. If you mix by weight, you can forget the pumps and move a bit faster, but you should aim to have hardener that means you aren't in a rush!

    For rollers, think one per session -- if you are going to do the entire first coat in one session, and then a single fill coat (epoxy slightly thickened with bubbles or something), then you need two. Having a few extras wouldn't hurt. West makes a roller cover that is 7"; you can cut it in half (hand saw or band saw) to fit smaller frames that are a bit easier to use.

    Like containers, squeegees can also be re-used: just wait until the epoxy cures and snap it off.
    Daniel

    Building a Campion Apple 16.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Hi Daytripper,
    Are you working alone on this, or will you have help? I tend to mix small batches (8-10 oz) to avoid having large quantities that might kick off before I can get it thinned out. However, I usually have help in the form of my ever patient lady or a friend. If you're stuck doing it yourself keep a tray of ice on hand that you can drop your mixing bucket into between batches. I like the thin nap 4" foam rollers that West sells (the yellow ones). I like to try to do my glassing as the day starts to cool down so the wood is warm and as air inside cools it draws epoxy in, rather than outgassing as it warms up and making bubbles. I assume you've read the West books on glassing...they have some great tips on handling the glass cloth and working the epoxy. I like the 206 hardener (I work slow) but use what you're comfortable with Have fun!

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    In no particular order:

    Use slow hardener unless you face temps under 60F. You don’t want to be hurried.

    I buy pint and quart deli tubs in case quantity. Maybe your deli would sell you a dozen or two. They can sometimes be re-used.

    When glassing something, I estimate how much epoxy it’ll take to fill it. Maybe 120% of the weight of the glass. I mix a first batch of 2/3 of the amount of epoxy estimated. When that’s gone, you can estimate how much to complete.
    Don’t delegate measuring epoxy. An error is a very bad thing.

    When applying glass to a hull, I cut it oversize, apply it dry and apply epoxy by pouring mixed epoxy onto it and pushing it around with a squeegee, the yellow plastic kind used for Bondo. Wipe them clean with paper towels when done. Buy a dozen. Squeegee technique is an acquired skill. You’re pushing a bunch of epoxy around to wet the glass, but no more and you want to keep it moving so it doesn’t end up on your shoes. Watch a commercial window cleaner. A 2” chip brush is needed for the last 5-10% of the job. Put used epoxy brush in a tall covered jar of acetone and shake it out for re-use.

    I seldom use rollers for epoxy. When I use rollers, I cut up 1/4” nap 9” rollers to 3”. And use the small rectangular plastic dishes Chinese food comes in.

    As an alternative to applying several fill coats of epoxy, consider using peel ply to get a smooth coating of epoxy over your glass. I think that it produces a better job with less epoxy and less labor. THis is thoroughly discussed elsewhere.

    In addition to the Gougeon book, I strongly recommend Russell Brown’s book on epoxy techniques.
    Last edited by JimConlin; 04-25-2022 at 08:58 PM.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by dbp1 View Post
    Hmm. 12 feet is not all that big, I don't think you need to overthink it. I've used left over plastic takeout containers that are ~16oz for most things and they seem to be fine (measure by weight, so the container you use doesn't matter). You can also usually re-use the containers -- once the epoxy has cured, flex the container and it should come out in a single layer (some plastic containers are more resilient to this than others). Ideally you have the right hardener so you aren't in a terrible rush and don't have to have premixed everything (in which case, you only need _one_ container per session!),but if you'd rather do that, then estimate how much glass, use the ratio for epoxy to glass. If you mix by weight, you can forget the pumps and move a bit faster, but you should aim to have hardener that means you aren't in a rush!
    I bought West Systems 206 slow hardener so there should be a bit more time. Reusing the same container per session is enlightening. I was concerned about the previous batch clinging to the sides and bottom of the container, even though scraped well, going off and affecting the next mix.

    For rollers, think one per session -- if you are going to do the entire first coat in one session, and then a single fill coat (epoxy slightly thickened with bubbles or something), then you need two. Having a few extras wouldn't hurt. West makes a roller cover that is 7"; you can cut it in half (hand saw or band saw) to fit smaller frames that are a bit easier to use.
    I bought PeelPly so it will be one coat on the entire outside of the hull in one session (glass + PeelPly). I will have at least 3 rollers on hand just in case. Plus need rollers to coat the inside with epoxy later anyway.

    Like containers, squeegees can also be re-used: just wait until the epoxy cures and snap it off.
    Thanks for the tips.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by Hugh MacD View Post
    Hi Daytripper,
    Are you working alone on this, or will you have help?
    I can ask my son for help and do it on his day off.

    I tend to mix small batches (8-10 oz) to avoid having large quantities that might kick off before I can get it thinned out.
    That is very helpful to know the batch size.

    However, I usually have help in the form of my ever patient lady or a friend. If you're stuck doing it yourself keep a tray of ice on hand that you can drop your mixing bucket into between batches. I like the thin nap 4" foam rollers that West sells (the yellow ones). I like to try to do my glassing as the day starts to cool down so the wood is warm and as air inside cools it draws epoxy in, rather than outgassing as it warms up and making bubbles.
    I saw the thin nap yellow rollers at West Systems but they only had the 7" length. Did not know that they also sell 4" lengths. I think I would prefer the 4" length also. I would like to start glassing as the day starts to cool down. Any guesstimate of how many hours it might take to apply one layer of 6 oz cloth followed by a layer of PeelPly on a 12 foot jon boat? I assume that the approximate time will be somewhat fixed due to the cure time of the epoxy so no dilly dallying during the process.

    I assume you've read the West books on glassing...they have some great tips on handling the glass cloth and working the epoxy. I like the 206 hardener (I work slow) but use what you're comfortable with Have fun!
    I'm reading the West online book now plus whatever else I can find online. I did buy the 206 slow hardener. Glassing with epoxy and PeelPly will be stressful for a first timer like me. Hope it's fun .
    Thanks for the help.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    The only epoxy squeegees I have used over the past couple of decades were cut from leftover blocks of ethafoam packing foam. When we buy something that comes packed in it, we save it, then I cut small slabs of it about 3/4" thick on the band saw or with a bread knife. Give one edge a bevel and you are ready to go - for free! I think they work much better for glassing than any of the others I've tried. They're soft, but not too soft, and firm, but not too firm, allowing you to get the cloth down tight to the wood and leave a really uniform surface texture with no excess resin, pooling, drips, etc. especially on the inside surfaces of the boat. They're disposable and in a few minutes, you can cut a batch of them so that there is no chance of running out.

    DSCF3881.jpg

    drift3.jpg

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by JimConlin View Post
    In no particular order:

    Use slow hardener unless you face temps under 60F. You don’t want to be hurried.
    Will be working in about 72 degree weather in our carport. Did buy West 206 slow hardener.

    I buy pint and quart deli tubs in case quantity. Maybe your deli would sell you a dozen or two. They can sometimes be re-used.
    Very helpful to know the size of mixing container to use. Do you reuse the same container or use a new container for every batch?

    When glassing something, I estimate how much epoxy it’ll take to fill it. Maybe 120% of the weight of the glass. I mix a first batch of 2/3 of the amount of epoxy estimated. When that’s gone, you can estimate how much to complete.
    I needed that tip.

    Don’t delegate measuring epoxy. An error is a very bad thing.
    After reading posts about epoxy not curing completely, I can thoroughly understand where you're coming from. It would be a disaster if that happens.

    When applying glass to a hull, I cut it oversize, apply it dry and apply epoxy by pouring mixed epoxy onto it and pushing it around with a squeegee, the yellow plastic kind used for Bondo. Wipe them clean with paper towels when done. Buy a dozen. Squeegee technique is an acquired skill. You’re pushing a bunch of epoxy around to wet the glass, but no more and you want to keep it moving so it doesn’t end up on your shoes. Watch a commercial window cleaner. A 2” chip brush is needed for the last 5-10% of the job. Put used epoxy brush in a tall covered jar of acetone and shake it out for re-use.
    Seems that using a squeegee is a recommended way to apply epoxy to minimize bubbles. But it's hard to imagine how to use a squeegee to glass the sides of the hull. Apply epoxy with a brush or roller and then squeegee the sides?

    I seldom use rollers for epoxy. When I use rollers, I cut up 1/4” nap 9” rollers to 3”. And use the small rectangular plastic dishes Chinese food comes in.
    Same question. Without using rollers for the sides, how is the epoxy applied to the side using a squeegee?

    As an alternative to applying several fill coats of epoxy, consider using peel ply to get a smooth coating of epoxy over your glass. I think that it produces a better job with less epoxy and less labor. THis is thoroughly discussed elsewhere.
    I just bought enough PeelPly yesterday, to do the entire outside of my hull. Expensive stuff but I guess it will be worth it doing the glassing in one coat with PeelPly. Less epoxy is good as I need my boat to be lighter.

    In addition to the Gougeon book, I strongly recommend Russell Brown’s book on epoxy techniques.
    I'm reading the Gougeon book now. I saw Russell Brown's youtube video on fiberglassing two hulls. He makes it look easy but I'm sure it's not easy as it looks. Especially tightening the cloth using the roller, even from a distance.

    Thanks for the help.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by DayTripper View Post

    I saw the thin nap yellow rollers at West Systems but they only had the 7" length. Did not know that they also sell 4" lengths. I think I would prefer the 4" length also.
    You can easily cut them -- a hand saw works fine. So a 7" one can become two 3.5" ones, which should fit the 4" frames fine, since at least the ones I've gotten expand somewhat.

    Quote Originally Posted by DayTripper View Post
    Any guesstimate of how many hours it might take to apply one layer of 6 oz cloth followed by a layer of PeelPly on a 12 foot jon boat?
    As long as you've precut and layed out the dry cloth on the boat (which will probably take a while!), I wouldn't imagine it would take more than a couple of hours: certainly if you can work a bit into the night, if you start in the afternoon, you should be able to get it all done at once.

    Quote Originally Posted by DayTripper View Post
    Reusing the same container per session is enlightening. I was concerned about the previous batch clinging to the sides and bottom of the container, even though scraped well, going off and affecting the next mix.
    There are people a lot more knowledgeable than me on here, but my understanding is that: epoxy cures by chemical reaction, accelerated by heat, and produces heat as it reacts. So if there is a tiny bit of starting to cure epoxy in the mix, it isn't going to "pollute" the rest (i.e., make it cure faster) -- and once it is dilluted, I would assume the reaction would slow down anyway. Obviously, if a pot is actually going off (heating up) then I wouldn't mix more into it, but when glassing, the process involves getting the epoxy out of the pot and onto the glass as soon as possible, so there is usually very little left in the pot after only a few minutes (and once there is barely any left, it should be reacting pretty slowly anyway). You don't want to waste epoxy anyway, so should have scraped it pretty clean with a squeegee anyway! Maybe my climate helps, but I've only ever had epoxy start to kick when filleting anyway (which seems easiest to do using a pastry bag, but that necessarily means there is a big batch of mixed epoxy in the bag as you work).
    Daniel

    Building a Campion Apple 16.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by DayTripper View Post
    Seems that using a squeegee is a recommended way to apply epoxy to minimize bubbles. But it's hard to imagine how to use a squeegee to glass the sides of the hull. Apply epoxy with a brush or roller and then squeegee the sides?


    Same question. Without using rollers for the sides, how is the epoxy applied to the side using a squeegee?
    You pour some high on the hull and both catch it with the squeegee as it runs down and spread it out, and then drag the excess from above down to the lower parts. It is thick enough that this works (i.e., you have a second or so as it runs down to catch it, unlike, say, paint if you poured it out like this).
    Daniel

    Building a Campion Apple 16.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by Todd Bradshaw View Post
    The only epoxy squeegees I have used over the past couple of decades were cut from leftover blocks of ethafoam packing foam. When we buy something that comes packed in it, we save it, then I cut small slabs of it about 3/4" thick on the band saw or with a bread knife. Give one edge a bevel and you are ready to go - for free! I think they work much better for glassing than any of the others I've tried. They're soft, but not too soft, and firm, but not too firm, allowing you to get the cloth down tight to the wood and leave a really uniform surface texture with no excess resin, pooling, drips, etc. especially on the inside surfaces of the boat. They're disposable and in a few minutes, you can cut a batch of them so that there is no chance of running out.

    DSCF3881.jpg

    drift3.jpg
    I remember having that type of packing foam and throwing them away. None lately though. Very ingenious idea to use that foam. Will definitely keep a look out for that type of packing foam since I have some time before glassing. Just starting my build now.
    Beautiful boat and craftsmanship!
    Thanks.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by dbp1 View Post
    You can easily cut them -- a hand saw works fine. So a 7" one can become two 3.5" ones, which should fit the 4" frames fine, since at least the ones I've gotten expand somewhat.
    I'll look into that idea. Thanks.

    As long as you've precut and layed out the dry cloth on the boat (which will probably take a while!), I wouldn't imagine it would take more than a couple of hours: certainly if you can work a bit into the night, if you start in the afternoon, you should be able to get it all done at once.
    That helps a lot for my planning.

    There are people a lot more knowledgeable than me on here, but my understanding is that: epoxy cures by chemical reaction, accelerated by heat, and produces heat as it reacts. So if there is a tiny bit of starting to cure epoxy in the mix, it isn't going to "pollute" the rest (i.e., make it cure faster) -- and once it is dilluted, I would assume the reaction would slow down anyway. Obviously, if a pot is actually going off (heating up) then I wouldn't mix more into it, but when glassing, the process involves getting the epoxy out of the pot and onto the glass as soon as possible, so there is usually very little left in the pot after only a few minutes (and once there is barely any left, it should be reacting pretty slowly anyway). You don't want to waste epoxy anyway, so should have scraped it pretty clean with a squeegee anyway! Maybe my climate helps, but I've only ever had epoxy start to kick when filleting anyway (which seems easiest to do using a pastry bag, but that necessarily means there is a big batch of mixed epoxy in the bag as you work).
    I'll try the single container and see how it goes. Will have extra containers on hand in case plan-B is needed.

    Thanks.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by dbp1 View Post
    You pour some high on the hull and both catch it with the squeegee as it runs down and spread it out, and then drag the excess from above down to the lower parts. It is thick enough that this works (i.e., you have a second or so as it runs down to catch it, unlike, say, paint if you poured it out like this).
    Sounds like skill is needed for that procedure. I'll have some rollers on hand just in case ... 😉.

    Thanks

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    I always use the yellow Gougeon rollers for glassing the outsides of boats (convex shapes with vertical sides) and the foam squeegees for glassing insides (concave shapes with vertical sides). The idea of slopping a bunch of resin up high and then trying to squeegee it out as it runs downward toward the floor is certainly not a great formula for getting a good consistent saturation of the cloth. Rollers can do three bad things - they can work tiny air bubbles down into the weave, they can lift the cloth away from the surface, and they can cause the resin to foam a bit. All of these are caused by rolling using too much speed and/or too much pressure. Back off a bit and you won't have those problems. Too much squeegee pressure can also foam resin.

    I also absolutely believe that the best thing you can do when glassing a boat is to get a helper who only does one specific job. They mix a steady supply of properly measured and properly stirred, medium-sized batches of fresh resin. The mini pumps are ideal for that job - better than pouring. That way you can concentrate on the application and watching for problems like bubbles or places where tension is pulling the cloth away from the wood, while somebody else concentrates on doing the mixing and measuring. It takes a certain amount of time for fiberglass cloth to saturate. If you are off mixing resin, you are not watching out for problems.

    Smallish batches also help to make sure that you are not trying to saturate cloth with resin which has already thickened enough in the pan to inhibit easy saturation. And get a bunch of Margerine tubs, Cool Whip tubs, etc. to mix resin in so that you are not trying to wipe out an old batch of still uncured resin in order to mix a new batch in the same tub. That's just nuts. Doing a good fiberglass job can be tricky and we see way too many mistakes being made. They can be expensive and trying to salvage what is under a problem fiberglassing job can be very difficult. Also have at least a couple of rollers ready to go. Sometimes they can get rather soft after a while, and/or clogged with hardening resin and it's better to switch to a fresh one.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    do yerself a favor and use 207 ,three to one special hardener, not 206 ,five to one slow.
    or.... wtf are you glassing a 12 foot jonboat for ?

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Some great advice above...if you haven't glassed before I suggest a little practice on a scap piece of ply, you'll get a feel for the materials as you combine them which would be useful. The peel ply (I found at least) is not as easy to handle and smooth out as you might expect especially if you plan on using big pieces. Screwing that up after a nice job laying the glass would be a real shame...

    Of course you could do sections at a time, bottom and then sides

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by Todd Bradshaw View Post
    I always use the yellow Gougeon rollers for glassing the outsides of boats (convex shapes with vertical sides) and the foam squeegees for glassing insides (concave shapes with vertical sides). The idea of slopping a bunch of resin up high and then trying to squeegee it out as it runs downward toward the floor is certainly not a great formula for getting a good consistent saturation of the cloth. Rollers can do three bad things - they can work tiny air bubbles down into the weave, they can lift the cloth away from the surface, and they can cause the resin to foam a bit. All of these are caused by rolling using too much speed and/or too much pressure. Back off a bit and you won't have those problems. Too much squeegee pressure can also foam resin.

    I also absolutely believe that the best thing you can do when glassing a boat is to get a helper who only does one specific job. They mix a steady supply of properly measured and properly stirred, medium-sized batches of fresh resin. The mini pumps are ideal for that job - better than pouring. That way you can concentrate on the application and watching for problems like bubbles or places where tension is pulling the cloth away from the wood, while somebody else concentrates on doing the mixing and measuring. It takes a certain amount of time for fiberglass cloth to saturate. If you are off mixing resin, you are not watching out for problems.

    Smallish batches also help to make sure that you are not trying to saturate cloth with resin which has already thickened enough in the pan to inhibit easy saturation. And get a bunch of Margerine tubs, Cool Whip tubs, etc. to mix resin in so that you are not trying to wipe out an old batch of still uncured resin in order to mix a new batch in the same tub. That's just nuts. Doing a good fiberglass job can be tricky and we see way too many mistakes being made. They can be expensive and trying to salvage what is under a problem fiberglassing job can be very difficult. Also have at least a couple of rollers ready to go. Sometimes they can get rather soft after a while, and/or clogged with hardening resin and it's better to switch to a fresh one.
    Thank you very much for your detailed help. Makes a lot of sense and I will do it. I gave my son a heads up this evening about needing his help on fiberglassing day. I'll buy a bunch of mixing cups and use a new cup for every mix.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by Benny View Post
    Some great advice above...if you haven't glassed before I suggest a little practice on a scap piece of ply, you'll get a feel for the materials as you combine them which would be useful. The peel ply (I found at least) is not as easy to handle and smooth out as you might expect especially if you plan on using big pieces. Screwing that up after a nice job laying the glass would be a real shame...

    Of course you could do sections at a time, bottom and then sides
    Hi Benny,

    Actually I did fiberglass a boat before about 40+ years ago. But at that time I used polyester resin. Using polyester, I was able to use laminating resin to apply the cloth, then to apply multiple coats of laminating resin on multiple days and it never cured hard until the final finishing resin coat was applied. The finishing resin contained wax that floated to the top and cured all coats completely by cutting off the air. The laminating resin made it low stress work.

    But epoxy appears to be a completely different thing. Learned that multiple coats need to be applied when the previous coat gets tacky to achieve a chemical bond. So to do that, everything needs to be done in one day. Plus the problem of amine blush which I didn't have to deal with using polyester laminating resin. So I decided to use PeelPly to simplify the multiple coats process and eliminate problems from amine blush.

    Your tip about PeelPly not being as easy to apply as one might expect is very helpful. I guess I'll need to apply it in two strips for the bottom instead of one large sheet as I have planned to do. Thanks for that tip.

    All new stuff for me so it will definitely be an adventure.
    Thanks

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by Todd Bradshaw View Post
    Smallish batches also help to make sure that you are not trying to saturate cloth with resin which has already thickened enough in the pan to inhibit easy saturation. And get a bunch of Margerine tubs, Cool Whip tubs, etc. to mix resin in so that you are not trying to wipe out an old batch of still uncured resin in order to mix a new batch in the same tub. That's just nuts. Doing a good fiberglass job can be tricky and we see way too many mistakes being made. They can be expensive and trying to salvage what is under a problem fiberglassing job can be very difficult. Also have at least a couple of rollers ready to go. Sometimes they can get rather soft after a while, and/or clogged with hardening resin and it's better to switch to a fresh one.
    I defer to your experience, but you say a roller can get clogged with hardening resin, which makes it seem like you don't toss them after each batch of epoxy... which means a little bit of the last batch, which is still on the roller, gets mixed in to the next batch. What's different about that and re-using the container that, similarly, has a little bit of the last batch in it? (and seems like _less_ than on the roller!). In either case, you're mixing a little bit of the last batch into the next stuff?
    Daniel

    Building a Campion Apple 16.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    The way we do it, it tends to be more of a "continuing" batch with continuing rolling, rather than a new batch/last batch thing and we're only mixing maybe 10-12 shots from a group B mini pump set at a time to keep the resin as fresh as possible. I also do my glassing using fast hardener 105/205, unless it's a clear finish where 105/207 looks better. I bought a can of slow hardener about 30 years ago and got tired of waiting for things to harden. I will use a roller until it starts to feel and perform differently from what it initially felt like. Then I'll toss it and get another one. Having originally started glassing things about 1967, and boats about 1972 when we just had polyester resin, you had to work fast because the pot life was only about fifteen minutes. After the switch to epoxy, fast hardener was actually a bit slower than the polyester stuff I originally learned on.

    When the Gougeon Brothers originally started selling WEST Epoxy and developing techniques to work with it, they originally sold the yellow foam rollers at their cost, because they were really superb tools for the job. At the time, they sort of hinted that they would keep the price as low as possible for years to come. I get the feeling that things have changed as the little buggers have gotten fairly pricey, but they're still the best I've used and waste less expensive resin just getting saturated than most others.

    As for containers or mixing bowls, one of the reasons that I don't have epoxy and glassing problems is that I do everything I possibly can do to avoid them. I will re-use a mixing container after it has hardened and the residual stuff has all been removed, but not the same day and not with any sort of "wet" epoxy in it. I just like to mix epoxy in clean, dry containers. It then gets dumped immediately into a roller pan or other shallow container to spread it out and keep the heat down. Given the price of resin, the price of boat wood, and the incredible hassle that sloppy or inattentive work can bring you as you try to fix dumb mistakes, just about any precaution can be justified.

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    What capacity mixing container is good for mixing resin when applying 6 oz fiberglass cloth? 32 ounce a good size? How many?
    I also need some smaller containers for measuring the resin and hardener as I think using the pumps will be too slow. What size for that?
    I think the most common mistake for beginners is to mix WAY TOO MUCH epoxy at a time. I built a bulky 18' sailboat and used the pumps for virtually everything. My biggest containers were used 32 oz yogurt tubs. But for the most part, I used smaller containers. For smaller boats, I use much 16 oz or even 8 oz containers. 12 oz paper coffee cups are cheap and work quite well. You'll get far better results from mixing up too little than you will from mixing up too much. Reread everything Todd advised and you'll be on the road to a nicely finished boat.
    -Dave

  22. #22
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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by Woxbox View Post
    I think the most common mistake for beginners is to mix WAY TOO MUCH epoxy at a time. I built a bulky 18' sailboat and used the pumps for virtually everything. My biggest containers were used 32 oz yogurt tubs. But for the most part, I used smaller containers. For smaller boats, I use much 16 oz or even 8 oz containers. 12 oz paper coffee cups are cheap and work quite well. You'll get far better results from mixing up too little than you will from mixing up too much. Reread everything Todd advised and you'll be on the road to a nicely finished boat.
    Thanks much for sharing the size of mixing containers you use and your tips. All info will be very helpful when the time comes to glass the hull.

    EDIT:
    Woxbox, you are the man! Your 12 oz paper coffee cups idea prompted me to search for 12 oz paper cups on Amazon.

    I found these 11 oz ice cream cups for hot or cold food on Amazon for only $7.99, 50 count.

    One of the pictures in the Amazon ad shows the dimensions. Cheap enough and throw away after one use. I think 50 cups should be enough for my small boat.

    Thanks!
    Last edited by DayTripper; 04-28-2022 at 01:54 PM.

  23. #23
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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Brilliant idea about the foam squeegees.

    You can buy a quantity of graduated cups from places like this Mixing Containers, Mixing Pails & Lids in Stock - Uline.ca

  24. #24
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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by Dave Hadfield View Post
    Brilliant idea about the foam squeegees.

    You can buy a quantity of graduated cups from places like this Mixing Containers, Mixing Pails & Lids in Stock - Uline.ca
    Thanks for that link.
    Thanks to Woxbox I found 11 oz paper ice cream cups, 50 count for $7.99. I put the link to them in my edited reply to Woxbox.
    Good deal to for one time use containers and discard.

  25. #25
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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Eat more yogurt.
    Steve Martinsen

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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by SMARTINSEN View Post
    Eat more yogurt.

  27. #27
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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Re: rollers -- I've not used them, as I'm pretty sure they are new, but it looks like Duckworks now carries rollers specifically for epoxy (presumably essentially off brand West -- not sure of quality, but generally Duckworks seems to do a good job not selling crap):

    https://duckworks.com/3-rollers-and-trays/

    Though it looks like the 7" rollers are the same price as the 3" ones, so you'd be better off buying the big ones and cutting them up!
    Daniel

    Building a Campion Apple 16.

  28. #28
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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Worth trying. I bought some off-brand "epoxy" rollers once. They looked good, but the epoxy softened the glue that held the foam to the cardboard and the thing started falling apart after 5 or 10 minutes of use.
    -Dave

  29. #29
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    Default Re: What size and quantity of mixing cups and foam rollers to glass a 12 foot boat?

    Quote Originally Posted by dbp1 View Post
    Re: rollers -- I've not used them, as I'm pretty sure they are new, but it looks like Duckworks now carries rollers specifically for epoxy (presumably essentially off brand West -- not sure of quality, but generally Duckworks seems to do a good job not selling crap):

    https://duckworks.com/3-rollers-and-trays/

    Though it looks like the 7" rollers are the same price as the 3" ones, so you'd be better off buying the big ones and cutting them up!
    dbp1 and Woxbox,

    I bought two 7" rollers from West Systems today. Will cut them in half to get four 3.5" rollers.
    I'll use the rollers to fiberglass the sides of my jon boat and do the pour plus squeegee thing to fiberglass the flat bottom.

    Thanks for the help.

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