I am building a Prospector Canoe, just about to the fiberglassing stage.
I would like to add an extra layer(s) of fiberglass cloth on the bottom for
protection as I am not installing a keel.
I would like some feedback.
1. Extra layer of cloth to be 4oz. or ?
2. Extra layer of cloth on all the bottom of the canoe?
3. Just a 12 in. or ? strip down the keel line
4. How far to extend the cloth up the stems ?
5. Would it be adviseable to apply a 6 in. wide piece of
cloth on top of the second layer?
6. Will three layers of cloth begin to blur the cedar strips?
7. What would be the best procedures to apply the layers
of cloth and resin e.g. two layer's at the same time?
8. Time to wait between layers of cloth and resin?
9. Do you kneed to fiberglass on top of the stem, 3/8 wide part?
Before the 3/8 brass band is installed.
10. I am using the WEST fiberglass system.
Thanks in advance for any suggestions you may have.
need help on applying more than one layer of fiberglass
A narrow strip of cloth along the keel line won't provide enough protection, since rocks could contact anywhere on the bottom... so I'd glass it all, up to about halfway on the hard curve up the sides.
An extra layer of 6 oz blurred the strips very slightly, and not noticeable at a distance... maybe test for effect if more layers are going to be applied, on a test panel of glued and sanded strips.
Wetting out two layers at once could result in problems with cloth shifting and trapped air, so I did them separately with good results, sanding down the first layer smooth. The extra layer was cut to size precisely by weighing down the glass so it would not shift, then trimming carefully with scissors. The weights stayed in place during wetout, being removed as epoxy was applied, starting at the center and working out.
After cure, the edge of the extra layer was faired in with a sanding block... this was easy, because there was a hard curve there and the edge of the extra layer was on it, making precise sanding on the edge possible.... the sanded and faired edge was not visible after varnishing.
I reinforced the stems and the area under the stems heavily with glass, because I did not add a metal stem band... you might want to add an extra layer or two with bias-cut cloth under the stem band, since this area gets the most abrasion.
Hope that helps... enjoy the build!
An extra layer of 6 oz blurred the strips very slightly, and not noticeable at a distance... maybe test for effect if more layers are going to be applied, on a test panel of glued and sanded strips.
Wetting out two layers at once could result in problems with cloth shifting and trapped air, so I did them separately with good results, sanding down the first layer smooth. The extra layer was cut to size precisely by weighing down the glass so it would not shift, then trimming carefully with scissors. The weights stayed in place during wetout, being removed as epoxy was applied, starting at the center and working out.
After cure, the edge of the extra layer was faired in with a sanding block... this was easy, because there was a hard curve there and the edge of the extra layer was on it, making precise sanding on the edge possible.... the sanded and faired edge was not visible after varnishing.
I reinforced the stems and the area under the stems heavily with glass, because I did not add a metal stem band... you might want to add an extra layer or two with bias-cut cloth under the stem band, since this area gets the most abrasion.
Hope that helps... enjoy the build!
-
Glen Smith
- Posts: 3719
- Joined: Sat May 08, 2004 9:08 am
- Location: Baie-St-Paul, Quebec, Canada
As Rick mentionned, wetting out two layers at once will produce trapped bubbles. West System recommend wetting out one layer and allowing it to dry until no longer tacky. Then you can layout the second layer of cloth and wet it out. Once it is no longer tacky, feather the seam, then you can apply the fill coats.
Lay out the second layer of cloth and you can cut it where it no longer wants to follow the curvature at the stems.
You didn't say what weight of cloth you will be using for the main layer. The second layer can be lighter, heavier or the same. That's us to you. I would say it depends on the areas where you intend to use the canoe. If intended for calm lakes, you don't need extra cloth. If intended for rocky rivers I would go with 2 layers of 6oz cloth.
On my first canoe I applied a narrow strip along the keel line but then again, as Rick said, most of the scratches occur further away from the keel line area.
An extra layer of cloth on the exterior will add abrasion resistance. An extra layer of cloth on the interior will add impact resistance. For heavy duty use, you can add a extra layer inside and outside.
I have applied up to 3 strips of bias-cut 6oz cloth on the outer stems of boats that don't have stem bands and doing them one at a time leaves them perfectly clear. Nobody even knows they are there.
Lay out the second layer of cloth and you can cut it where it no longer wants to follow the curvature at the stems.
You didn't say what weight of cloth you will be using for the main layer. The second layer can be lighter, heavier or the same. That's us to you. I would say it depends on the areas where you intend to use the canoe. If intended for calm lakes, you don't need extra cloth. If intended for rocky rivers I would go with 2 layers of 6oz cloth.
On my first canoe I applied a narrow strip along the keel line but then again, as Rick said, most of the scratches occur further away from the keel line area.
An extra layer of cloth on the exterior will add abrasion resistance. An extra layer of cloth on the interior will add impact resistance. For heavy duty use, you can add a extra layer inside and outside.
I have applied up to 3 strips of bias-cut 6oz cloth on the outer stems of boats that don't have stem bands and doing them one at a time leaves them perfectly clear. Nobody even knows they are there.
Re: need help on applying more than one layer of fiberglass
This is my 2 cents worth.
1. Extra layer of cloth to be 4oz. or ?
Use whatever you are using for the rest of the canoe.
2. Extra layer of cloth on all the bottom of the canoe?
Yes, I cut out a football shaped piece, then I put the full sized piece on, and glass them together. West soaks through for me fine, without air bubbles.
6. Will three layers of cloth begin to blur the cedar strips?
Two has held up for me.
8. Time to wait between layers of cloth and resin?
I've always put all layers of epoxy on ASAP. Four coats takes from about 3:00 in the afternoon, until about midnight.
Hope this helps,
Philz
1. Extra layer of cloth to be 4oz. or ?
Use whatever you are using for the rest of the canoe.
2. Extra layer of cloth on all the bottom of the canoe?
Yes, I cut out a football shaped piece, then I put the full sized piece on, and glass them together. West soaks through for me fine, without air bubbles.
6. Will three layers of cloth begin to blur the cedar strips?
Two has held up for me.
8. Time to wait between layers of cloth and resin?
I've always put all layers of epoxy on ASAP. Four coats takes from about 3:00 in the afternoon, until about midnight.
Hope this helps,
Philz
philz
Re: need help on applying more than one layer of fiberglass
I built a kayak, not a canoe, but FWIW, here's my $0.02.
* I put a second layer of 6oz glass over the "football" on the bottom. Judging by the pattern of scratches on the hull, this provides greater protection than a narrow keel strip would have.
* I did not extend the extra cloth to the stems ... I dealt with the stems separately.
* I wet out both layers at once, but as noted upthread, its hard to control air bubbles this way ... next time, I will wet out the glass one layer at a time.
* I didn't use a brass stemband, so can't comment on that ... I simply rounded off the outer stem, which in my case is ash.
* At the stems, I have 3 layers of 6oz glass ... I cut the glass long enough that it would wrap around the stems by about 1" from each side, and then placed another strip of glass, about 4" wide and cut on the bias, over top of the two wrapped ends. All was wet out in one session, although laid one layer at a time. There is no blurring of the wood grain, it is perfectly clear.
Good luck with the glassing ...
* I put a second layer of 6oz glass over the "football" on the bottom. Judging by the pattern of scratches on the hull, this provides greater protection than a narrow keel strip would have.
* I did not extend the extra cloth to the stems ... I dealt with the stems separately.
* I wet out both layers at once, but as noted upthread, its hard to control air bubbles this way ... next time, I will wet out the glass one layer at a time.
* I didn't use a brass stemband, so can't comment on that ... I simply rounded off the outer stem, which in my case is ash.
* At the stems, I have 3 layers of 6oz glass ... I cut the glass long enough that it would wrap around the stems by about 1" from each side, and then placed another strip of glass, about 4" wide and cut on the bias, over top of the two wrapped ends. All was wet out in one session, although laid one layer at a time. There is no blurring of the wood grain, it is perfectly clear.
Good luck with the glassing ...