glassing bottom on pirogue
- Thread starter jdupre'
- Start date
jdupre' said:
I don't blame you. I haven't been all that eager to try it either, and I've been speculating about it for a while.
If it will work on a bow, I bet it will work on a boat. I gotta do an experiment. Been thinking about a combination seat / storage box - that might be a good test.
George
George,
I'm not familiar with this paper, I don't think. Is it just paper? Or, does it have fibers running through it for reinforcement?
I'm not familiar with this paper, I don't think. Is it just paper? Or, does it have fibers running through it for reinforcement?
George, I have to say your call on using paper just might be an answer. . .
Medium density overlay ply (paper backed ply) came into being in part to control checking of the plys and provide smoother surfaces for painting. . . Using a heavy weight paper should work just as well and ,perhaps, even better, with epoxy saturation. . .
I'm not sure how well rosin paper would work, though, if I remember correctly (and I'm not sure I do), doesn't rosin paper's coating contain a parafin of some kind or some kind of oil ? . . . But a paper with a weight similar to brown paper bags or slighly heavier should work? Correct me if I'm wrong, because like I said, I'm not sure if I remember correctly about rosin paper's make up. . . .
Medium density overlay ply (paper backed ply) came into being in part to control checking of the plys and provide smoother surfaces for painting. . . Using a heavy weight paper should work just as well and ,perhaps, even better, with epoxy saturation. . .
I'm not sure how well rosin paper would work, though, if I remember correctly (and I'm not sure I do), doesn't rosin paper's coating contain a parafin of some kind or some kind of oil ? . . . But a paper with a weight similar to brown paper bags or slighly heavier should work? Correct me if I'm wrong, because like I said, I'm not sure if I remember correctly about rosin paper's make up. . . .
Steve said:
Steve,
MDO is exactly what made me think about this to start with.
Rosin paper may not be suitable - we'd need to figure out what exactly is in it. Locally, they sell a product called "builders paper" which is essentially the same stuff a brown paper grocery sack is made of, but perhaps a little thicker.
Jack,
The papers I am referring to are just paper, no special reinforcing fibers or anything of that sort. Of course there are a world of different paper products out there that a person could choose from and experiment with. Remember when you are thinking this over, that I'm not suggesting that this would add the kind of strength that 'glass does. I'm suggesting that it might be a way to control checking on fir or pine plywood, while saving some money and weight vs. fiberglass cloth.
Just something to think about.
GBinGA
I once repaired some plastic fan blades with pieces of cotton handkerchief and cheap, 2-part epoxy. They lasted another 25 years. The type of fabric may not be all that important? But, it seems important that there is some fabric of some kind there.
Obviously, some fabrics would contribute more strength to the mother material than others. But, it seems that having anything there is much better than nothing. That first step seems to be the important one.
Obviously, some fabrics would contribute more strength to the mother material than others. But, it seems that having anything there is much better than nothing. That first step seems to be the important one.
Kayak Jack said:
I think of the fabric as being like the rebar and/or rewire in the concrete. Concrete is far from useless without reinforcement, but put some wire or bar in it and you have a big improvement. So what I wonder is whether paper might be a low cost low weight alternative for some of us.
Lot's of different scenarios out there---
-A retired fellow who fishes a lot and hardly ever uses anything other than his kayak and fishes rivers needs one kind of cost / weight / durability compromise.
-A guy still working who is lucky to fish once a week and sometimes uses the jonboat and hardly ever fishes moving water needs a different cost / weight / durability compromise.
Whether paper has any value at all in this - I don't know. But it seems like an interesting question.
George
I saw someone make paper from scratch one time at an arts and crafts show. They threw a bunch of different colored and styles of paper in a blender, filled the blender with water, and pureed the whole mess up. They then poured it onto a screen which trapped the pulp and let the water drain out. A little drying and Presto, paper. All of the tiny pieces of fibers locked into each other and made a tough sheet of paper. If you take all of those interlocking fibers and saturate them with epoxy, I would think you would come up with a pretty tough material.
In studying knifemaking, I came across a similar concept. There is a material called linen Micarta. It is made with layers of linen cloth saturated and built up into material about a half inch thick. I'm not sure about the type of resin they use, but my guess is that it is some kind of epoxy. After hardening, the material grinds and polishes out just like a really hard , fibrous wood. Tough stuff.
Joey
In studying knifemaking, I came across a similar concept. There is a material called linen Micarta. It is made with layers of linen cloth saturated and built up into material about a half inch thick. I'm not sure about the type of resin they use, but my guess is that it is some kind of epoxy. After hardening, the material grinds and polishes out just like a really hard , fibrous wood. Tough stuff.
Joey
It sounds here, like we're talking about craft paper. Heavy, brown butcher paper. Interesting reinforcement material.
Kayak Jack said:
Yeah - that's it, exactly. Although some other kind of paper might be just as good or better. The brown paper is just what I keep seeing laying around in the paint department at the home center.
Like Steve was saying, MDO, which is just plywood with a paper facing, is what gave me the idea. Cheap as paper is, I was thinking that the thing to do would be to face the plywood with paper before building the boat.
Of course one obvious drawback to this is that it would be a painted application only. No pretty wood grain.
Might be a silly idea. Just keeps popping into my noggin, along with all the other (possibly silly) ideas that bounce around in there.
George
Speaking of fabric. . . .being half asleep right now maybe someone has mentioned this and I don't realize it. . . PT boats used cotton muslin as reinforcement back in WWII. . . Of course it was placed between the plywood sheets. . . Added a heap of strength that way. . . Didn't do much in the way of stopping bullets, torpedos, or other boats but sure made it capable of maintaining high speed. . .and with three big desel engines put in the right configuration to move sideways at times, those hulls took some serious pounding. . .
I suppose if a man wanted to paint his boat 
, MDO is a tad more spendy that what is usually used by folks on this site but it might be an option due to it being all paint :cry: ready and such. . .
:shock:
Naw. . . . . . . . . . .what am I thinkin'? :lol:
, MDO is a tad more spendy that what is usually used by folks on this site but it might be an option due to it being all paint :cry: ready and such. . . :shock:
Naw. . . . . . . . . . .what am I thinkin'? :lol:
Steve said:
Having worked on a few Huckins which built a lot of multi layered PT hulls, building during those years using the method you subscribe has many reasons for the methods and components you bring up. Way back when carvel planked boats had its issues in the area of leaks, maintainance and weights too. Along the Chesepeake Bay, tar has always been used too which did double duty for allowing two layers of woods to move about and minimize or even stop leaks. Complete decks on solid planked hulls used a thin layer of felt between canvas overlays too and deal with the issues of dampness that can get trapped between multiple layers of components too.
The old MDO was decent plywood unlike what you get now. The number of layers and the types of wood in the layers of the junk now for sale causes me to forgo such when picking up MDO off the shelves of the lumberyard. Some of the plywood layered with the paper now has birch dust inside. So buyer beware.Steve said:I suppose if a man wanted to paint his boat
:shock:
Naw. . . . . . . . . . .what am I thinkin'? :lol:
While I was only jesting in part about building with MDO, I thank you for the info, Oyster. . . In the past I have made some painted cabinetry with the stuff but if the quality has dropped then I'll avoid it. . .
When did the almighty dollar become more important than a person's (or a corporation's) integrity and quality? Dang shame that be the case these days. . . (Granted, there be aspects of mine which are in sore need of repair , but still, I am trying to work on that . . .)
When did the almighty dollar become more important than a person's (or a corporation's) integrity and quality? Dang shame that be the case these days. . . (Granted, there be aspects of mine which are in sore need of repair
, but still, I am trying to work on that . . .)Indeed there are many boats that are still plowing the waters in good old fashioned MDO plywood. There are also yachts built using MDO in their superstructure where strength was required which fir plywood actually gives you. A really big issue with MDO even when its good is actually satuating the overlay for full bonding of any topcoat or even glasswork. You really need to seal the paper with a thin layer of wood sealer or epoxy until you can no longer see dull areas and then sand and begin your process of painting.Steve said:While I was only jesting in part about building with MDO, I thank you for the info, Oyster. . . In the past I have made some painted cabinetry with the stuff but if the quality has dropped then I'll avoid it. . .
When did the almighty dollar become more important than a person's (or a corporation's) integrity and quality? Dang shame that be the case these days. . . (Granted, there be aspects of mine which are in sore need of repair
Signs are all over the country that are also made of the stuff and have lasted for years without any maintainance too.
I spent a couple of hours sanding the paint off of the bottom of the pirogue yesterday in the 100 degree heat. Fun. :roll:
I used my 3x18 belt sander with 120 grit belts which was all I had. It did the job but was slow. Today after work I went to Lowe's an got a few 40 grit belts. MUCH better. I sanded one side this evening in about 25 minutes. That's one good thing about 1/4" plywood- there is a lot of leeway in sanding it. My problem is going to be getting to the paint that has soaked into the porous, earlywood layers.
I used my 3x18 belt sander with 120 grit belts which was all I had. It did the job but was slow. Today after work I went to Lowe's an got a few 40 grit belts. MUCH better. I sanded one side this evening in about 25 minutes. That's one good thing about 1/4" plywood- there is a lot of leeway in sanding it. My problem is going to be getting to the paint that has soaked into the porous, earlywood layers.
Kayak Jack said:
Maybe, but she's part of the family now. Kind of like a house. If something goes wrong with your house (and you really like your house) do you repair it or buy another house?
Joey