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PostPosted: August 22nd, 2014, 11:56 am 
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Joined: June 28th, 2001, 7:00 pm
Posts: 1810
Location: Freeland, Maryland USA
Thanks Charlie.

I just bought another yard of release treated peel ply from my local outfitter. It is kind of a hassle for them to get the roll down, unwrap it, measure, cut, and put everything away. They are a little pricier than Express Composites but I doubt it is worth their while delving into their own shop supplies for my needs.

Next time I need peel ply I’ll order from Express.
http://www.expresscomposites.com/vbag.html

I am aware that there is an inherent danger in placing that order – Express Composites has some useful stuff in their product line.
http://www.expresscomposites.com/


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PostPosted: August 22nd, 2014, 12:23 pm 
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Joined: June 28th, 2001, 7:00 pm
Posts: 1810
Location: Freeland, Maryland USA
On a related topic, how green should epoxy be if topcoating with the same epoxy. The specific epoxy probably matters, so West System 105/206 slow hardener.

Is green 2 or 3 hours later or is 12 hours later still green enough?

I have not liked the epoxy surface I’ve achieved with a green pull after a couple of hours, especially not in contrast to the surface revealed leaving release treated peel ply on overnight.

I’m sure I could pull the release treated stuff cleanly after 4 or 5 hours, but being able to sequence epoxy work so that I can put the canoe to bed in the evening and pull the ply when beginning afresh the next morning has advantages.


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PostPosted: August 22nd, 2014, 9:14 pm 
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Joined: July 29th, 2009, 9:29 am
Posts: 387
Location: Lower Saranac Lake, NY
The Swenson family was a great source for Bell Canoe when I was there, and to Placid boatworks a decade later and now to Colden Canoe. Solid experience, good advice, and dedicated to helping starting/intermediate builders. Great Folks.

R.e. green pulls with peel ply. It's so dependent on gel/set times that I'd be afraid to comment, especially on epoxy. Once I discovered treated peel ply I never used untreated again, and that's been a very long time.

Working in infusion shops, Placid, Colden, Swift, the good stuff arrives by the roll or pallet.


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PostPosted: August 23rd, 2014, 8:48 am 
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Joined: August 14th, 2012, 10:19 am
Posts: 184
Mike McCrea wrote:
On a related topic, how green should epoxy be if topcoating with the same epoxy. The specific epoxy probably matters, so West System 105/206 slow hardener.

Is green 2 or 3 hours later or is 12 hours later still green enough?

I have not liked the epoxy surface I’ve achieved with a green pull after a couple of hours, especially not in contrast to the surface revealed leaving release treated peel ply on overnight.

I’m sure I could pull the release treated stuff cleanly after 4 or 5 hours, but being able to sequence epoxy work so that I can put the canoe to bed in the evening and pull the ply when beginning afresh the next morning has advantages.

With regard to timing of a second coat of epoxy, are you primarily concerned about getting a good chemical bond between epoxy coats, or avoiding amine blush interfering with bonding of the second coat? My guess is that the sooner a second coat of epoxy is applied the better the chemical bond will be. I doubt amine blush would be a problem even if you allowed the epoxy to cure overnight.

I am usually working with West System's 105 resin and 206 hardener as well. I am often working outdoors in southern Indiana summer heat and humidity, in an enclosed back yard with a light-colored concrete patio surface reflecting heat, so my epoxy sets pretty quickly.

If I am doing something fairly limited like applying a small to moderate sized fiberglass or aramid patch or glassing in some nylon webbing anchors I will typically remove untreated peel ply as early as the epoxy lets me do so without lifting any fibers. That is typically within 2 hours. If I do not want the matte finish texture left by the untreated peel ply I will go ahead and apply another coat of epoxy right then, and as soon as that sets pull off the masking tape surround. I have not encountered any problems doing this.


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PostPosted: October 16th, 2014, 8:34 am 
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Joined: October 14th, 2010, 2:51 pm
Posts: 43
I've used general fabrics as peel ply, and sometimes got excellent results. The problem I have run into is that to get good prices we buy some scraps and by the time we get something we like, we probably can't get any more. I agree that the real stuff is probably worth it, but for the home guy it gets expensive. There isn't any pay-out at the end of the process. Infusion in particular is a specialized case, and requires a lot of product to get a good job. Rocking, but the pile of expensive garbage at the end of the process is somewhat staggering.

There is something to be said for just getting better at doing the work. I have had the opportunity to work with a few masters, and they can turn out work in minutes that would take others days. It isn't normally a skills think, in the sense that they have a special wrist action, or something. The most important part is having a process that works and is meticulously adhered to. Minor changes in process, while doubtless valid in their own way (or no problem in certain cases) can wreak everything. They need to be included in their own process not inserted in another. I first learned that when doing dry wall. By that time I had been doing epoxy work probably 20 years. But what I picked up is that in this kind of work the logic really drives it. The first coat buries the fiberglass tape, or embeds the paper; second coat covers 100% of the tape, and has a smooth ridge from a cambered trowel; Third coat indexes off the cambered ridge and widens the patch, etc... There are many ways to do this stuff, but whatever way it is done, you need to complete one full step a cycle, for the whole work area, and do it in some logical pattern. The first part covers speed, the second part also quality.

Blush is for the most part a non-issue. It comes off with tap water. WEST was the first product out there and still probably the best. So everyone who came after WEST has tended to index their product features off WEST. Blush is a vulnerability of WEST, but if it was something that could be easily adjusted out of the formula without affecting central properties it would have been eliminated years ago. I have been using WEST over 35 years, and it has rarely been an issue, and never one I couldn't get past with just a wipe down with some water.


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