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glassing interior stripper hull

Discussion in 'Strippers, Stitch-n-Glue, and Other Wood Composite' started by donwells, Jun 19, 2015.

  1. donwells

    donwells Curious about Wooden Canoes

    I have a 16 footer and when i did the outside i had no problems at all with it. I got started on the inside and had as smooth as a babies butt I laid out the cloth and brushed it out to where there were no wrinkles and fit perfectly. I started at 0800 this morning and just walked away from it a few minutes ago which was 1130 everything i read said that you wanted a matt finish. so when i started this morning i mixed 6oz batches of epoxy at a time. I intended to start out working in quarters but that got sidetracked. when i poured the epoxy in the bottom and started trying to move it around with the squeegee the cloth kept lifting off of the bottom with air bubbles under it and i was constantly fighting those as i went to the point that before i got to the other end the first was set to the point that you couldn't do anything with it. I believe i have too much epoxy but i couldn't get the cloth to stay laid down when i tried to squeegee it out. I used over a 1/2 gallon of resin by the time i was finished and as far as a needing a grunge can that was non existent because it would lift away from the bottom as i tried to work it out so to say the least i don't have a mat finish for the most part. Is there any tricks or suggestions to where i can get this to lay down and stay as i work and apply the rosin. the temp was around 75 degrees when i started and when i stopped it is now around 90. i did have it in the garage so at least it wasn't in direct sun. Please give me some pointers as to what or how i need to do this. Thanks.
  2. Todd Bradshaw

    Todd Bradshaw Sailmaker

    Your cloth is lifting because as you roll or squeegee resin into it, it moves a little bit. This is both normal and unavoidable. The trick (or the problem) is what direction it is moving. The typical action of dumping resin into the middle of the hull and squeegeeing it up the sides tends to move cloth away from the middle of the canoe, creating enough cloth tension to pull it up out of the hollows. This makes very stubborn bubbles and gaps that are very difficult to fix - unless you move some cloth back in there where it can lie down tight to the surface and relax. So what you want to do in those situations is to squeegee toward the trouble spot, moving cloth in there to reduce the tension. The interior glassing job then becomes a mixture of the typical upward squeegee strokes and various strokes downward, sideways or whatever it takes to get all the glass down tight and bubble-free.

    I usually cut the factory selvedge edges off of big pieces of cloth before a job like this. It frees-up the weave a bit and helps the cloth conform without wrinkles. Also, do not apply the glass, close the door and walk away. You may have some spots that still have enough tension for bubbles to form a few minutes later - which might need some attention. Stick around long enough for the resin to start stiffening and lock it all in place.
  3. OP

    donwells Curious about Wooden Canoes

    OK, Good advice for the next one but as far as what i have to deal with now where a lot of the cloth is completely covered and some isn't would my best option be to go back over it with another layer after it tacks up and fill in the rest of the weave or just settle with what i have. As of now the gloss and matte finishes sure don't go good together.

    Approximately how much resin should it take to do the interior of a canoe this size IF it was done correctly?
  4. Todd Bradshaw

    Todd Bradshaw Sailmaker

    Some folks fill the weave on the inside for a cleaner look, others can't see adding the extra weight but it is something you could do if you want to even out the look of it. Since both the inside and outside will need varnish as a final finish and UV barrier, the amount of gloss (or not) will also be a product of the varnish used.

    I don't know on quantity. I always had plenty on hand and just kept mixing small batches until the job was done. Maybe a gallon or so for a typical tandem canoe's interior???? It's going to depend on the cloth used and application skills of the builder, plus how much you waste. Having an assistant you can trust who does nothing other than mixing you a constant stream of accurately measured small batches of resin as you apply the cloth makes the job go much smoother, leads to fewer mixing errors, and reduces the amount of wasted resin.
  5. Jim Dodd

    Jim Dodd LOVES Wooden Canoes

    I have always struggled with squeeges !

    Lately, I've become real fond of those white dense "cigar" foam rollers ! They come in 4 and 6". Either work fine ! I didn't have any issues with the resin turning Milky, and was able to spread the resin evenly. Adding my fill coats was a breeze !

    I start in the middle, work towards one end, doing both sides at once. The long handle on the roller frame makes it possible. Then return to the middle and work towards the other end.

    I wet the ends out, but don't spend much time on them, until I'm happy with the mid section. Then I come back and finish the stems.

    As for how much resin I use ? I just did a solo, 15' 10". On 6 oz cloth, I used 45 oz for the first wet out coat. I applied a previous seal coat using 24 oz. Felt that I used too much resin !

    As for your situation, without seeing it, I'd apply another fill coat.
    I prefer a smooth finish on the inside. If you ever need to come back and do anything to the inside, like glass work, the removal of the varnish won't be a problem. Besides a smooth finish is easier to clean.

    Glassing can get real nerve racking ! It's great to have and experience helper when glassing !

    Hope it works out for you ! Funny how doing that first canoe is like learning to ride a bike ! You do soo much better the next time !!!

    I'm always reminded of a friends canoe that cracked down the middle in the BWCA, he was so proud of how light weight his canoe was ! Good thing we had Duct tape !

  6. Jim Dodd

    Jim Dodd LOVES Wooden Canoes

    I meant to ask what kind of resin and cloth you used?
    Some resin and cloth combinations are not compatible.
    Did you get cloth and resin from the same supplier ?

  7. Jim Dodd

    Jim Dodd LOVES Wooden Canoes

    Small air bubbles appear, while glassing when temperatures are rising. This is caused from air expanding, either in the wood or from staple holes. They are like tiny balloons being blown up through the uncured resin. A remedy while glassing, is to warm the hull and wet resin with a hair drier. This will increase the bubbles. Take a foam brush and pop them, as the hull cools, they SHOULD greatly diminish.
    Again this is too late to help you now.

  8. mccloud

    mccloud "Tiger Rag" back on the tidal Potomac In Memoriam

    To Jim & Todd: This question is from somebody who has very little experience with glassing, but what would be wrong with laying in the glass, then adding just enough epoxy to work it in 2 or 3 inches wide along the keel line, then taking a break of 3 or 4 hours until the resin partly sets and holds the glass in place? Would this not solve the problem Don has had? Does it create new problems? Tom McCloud
  9. Todd Bradshaw

    Todd Bradshaw Sailmaker

    It's nearly impossible to make a clean "stop line" with resin on fiberglass cloth. A certain amount is going to wick into the fibers and at the extreme edges of this you get some partially saturated glass, which remains white-ish. If you let that part start to harden, it will never saturate properly and go clear when you go back in to finish the job.

    People have tried all sorts of methods for holding fiberglass in place while saturating - from staples and pins, to tape, to clamps, to clothes pins, to sticky base coats of resin that haven't completely hardened yet. In general, they're more "problem creators" than "problem solvers". The best bet is usually to simply understand that the cloth is going to move some as you saturate it, and the bigger the cloth piece, the more potential movement there is. So rough-cut your cloth a bit larger than the hull, start somewhere in the middle moving resin and cloth as needed and working outward toward the ends. Once you get the hang of squeegeeing or rolling cloth toward tight spots to prevent pull-aways, it's really pretty straightforward. If you're getting foaming and lots of small bubbles down in the weave with either a squeegee or a roller, it usually means that you are pushing it too hard or too fast (or both). Ease off on the pressure a bit and slow your strokes down. It takes the cloth some time to absorb the resin as you saturate it and there is really no way to speed that up and force resin into the fabric during a hand lay-up job. You can even cut cloth to fit as you saturate it if you've covered the area and the excess fabric is in the way. Your scissors will get goopy, but vinegar will take uncured epoxy resin off of them (or you).

    I also dislike most commercial squeegees. A lot of them are too stiff, some have sharp corners that snag the cloth and I'm too lazy to clean them. I roll resin when possible, but on insides I usually squeegee it instead. Back in the days when Norm Sims and I started building boats we didn't have much money and we would cut slabs about 1/2" thick from hunks of white ethafoam packing material (the flexible foam that TVs come packed in) with a fillet knife. They are still, by far, my favorite squeegees. The foam is stiff enough to move resin and cloth, but soft enough not to snag it or overly agitate the resin. They're free, and when done you throw them away. If you plan on leaving the weave texture inside as a non-skid, a few light final strokes with one will "comb" the surface out to a very even and decent-looking woven pattern. I have my wife trained, so if they get something new in at her lab at work that came packed in ethafoam, she saves those pieces and brings them home.
  10. Jim Dodd

    Jim Dodd LOVES Wooden Canoes

    I agree with Todd
    Glass the entire hull at one time, saves a lot of head aches later on! Usually once the cloth is wetted, it sticks a little, lighten the pressure on the squeegee.

    Or better yet use the NEW cigar foam rollers ! They weren't INVENTED when Todd or I started building canoes ! They really work fine !

  11. Jim Dodd

    Jim Dodd LOVES Wooden Canoes

    IMG_0325_zpslmepixrz.jpg Here is a pic of the rollers I have graduated to.

  12. OP

    donwells Curious about Wooden Canoes

    Sorry that it has been a while since i last checked in .

    I got all of my supplies from RAKA and i have no problem with the product itself at all. The epoxy has a UV inhibitor added. I got a 3" 3/8 dis glass roller and metering pumps to go along with it I put down a layer of 4 oz on the football and a complete layer of 6 oz over that and wet it out all at once i also added multiple layers over this at the bottom of the bow and up the stem,s an. I initially sealed the hull with epoxy so as to slow down the out gassing and played the rest while it was still green, i did have a little but that was all.

    i have since sanded everything and there are several little bitty shiny spots should those be sanded completely out or will the next coat smooth those out and give me a slick finish where it fills and levels those areas,

    Would 220 grit wet&dry paper be fine enough for the final sanding before i take it to a paint shop and have it shot with a commercial clear coat, at least that is my intention now
  13. OP

    donwells Curious about Wooden Canoes

    As far as the squeegee goes i use the foam also and liked the way that it handled but i got mine from home depot where they were going to throw a sheet away that was broken. It is the pinkish 1/2 inch 4X8 sheet of insulating foam it has a film of plastic on both sides but you just take it at the edge and remove it from the sheet or piece that you cut off to use, worked good and i even used some more than once when the epoxy set up i just hit it with the sander and run it down to the clean foam and reused it again.

    The roller that i initially used i got at the hardware store it was a 3" lintless roller but they can't be reused it stuck to the frame to the point that i couldn't even get it off and reuse the frame.
  14. Jim Dodd

    Jim Dodd LOVES Wooden Canoes

    Hi Don
    If you go to my previous post, you will see the rollers I use. RAKA carries them. As well as Menards, and Home Depot.

    When you wet out the cloth with resin, the first time. Let it set, past the tacky stag.. At this point start your fill coats. After you apply the first fill coat wait one to two hours, and apply another fill coat. This makes an excellent bond, because the previous coat is still tacky, and will hold the resin, and keep it from running.

    Don't stop applying fill coats, until all hint of the weave is gone. 3 or 4 fill coats usually does this . No Sanding between coats. This will give you the clearest glassing job.

    I would use high pressure air to clean those pin holes, and maybe recoat with epoxy.

    The little shiney spots shouldn't be a problem.

    Congratulations !

    Last edited: Jun 30, 2015

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