Fiberglassing the stems

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Rockford
Posts: 8
Joined: Thu Mar 22, 2018 8:45 am

Fiberglassing the stems

Post by Rockford »

Hello everyone. I have been searching the posts and trying to understand how the bias cut fiberglass laid over the stems can just become transparent after the epoxy is applied. I read on the forum that sanding too much epoxy off the hull and sanding into the fiberglass will cause it to be visible. I also read that when covering the stems with extra layers of glass I will need to scrape the edges of the bias cut glass to create a smooth transition. I'm assuming that this means scraping the edges of the epoxied fiberglass and tapering the thickness to a nice smooth transition from two layers to one layer. I'm missing something here. If I break into the glass at the edges to taper the thickness, will this area show the scraped fiberglass thru the finish? Maybe another way of asking this question would be; how do I smooth out this transition area? Buildup an epoxy layer at the edges of the fiberglass and taper the epoxy? Is it ok to scrape the fiberglass? I'm confused on this, can someone point me in the right direction?

Andy
Rockford,MI
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Jim Dodd
Posts: 1359
Joined: Wed Feb 08, 2006 11:08 pm
Location: Iowa

Re: Fiberglassing the stems

Post by Jim Dodd »

In my experience, and this is the way I do it.
After I have wetted the main layer of cloth, and the epoxy has hardened enough, that I can trim it at the stems. A razor blade works great.
I lay the widest bias strip. Wet it out, and immediately lay the narrower on on and also wet it. Yes there will likely be some fray edges, but I don't worry about them now. Everything is wetted. Then I apply fill coats two to three, of epoxy.

I love a carbide scraper, but any slightly curved scraper will work ! I even use an old pocket knife sometimes !


After everything has cure say 24 hr, and the epoxy is still a little soft, I come back and scrap and feather the bias strips. so the blend by feel with the rest of the cloth. Yes you will see the transition . Later at least a week, I'll sand the entire hull. And yes again, you will still see the lines of the Bias strips. When you varnish they will disappear.

The above method makes it near impossible the see where the bias are.

The real key is to add the bias strips, before applying fill coats, and shortly after you have wetted out the main layer.

Image

Image

Image

Image

Image

The above canoe has two bias strips, plus an additional layer of cloth, over the football. I can not tell where the extra layer, or bias strips
start !
Keep your paddle wet and your seat dry!
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Cruiser
Posts: 867
Joined: Sat Apr 27, 2013 10:21 am
Location: Bowmanville, Ontario

Re: Fiberglassing the stems

Post by Cruiser »

Hi Andy,

I did a detailed description of laying down those bias strips in my last build here: https://www.canoetripping.net/forums/fo ... uild/page8

It covers the bias strip cutting, area prep, application ... basically all the stuff you are asking.


Brian
Rockford
Posts: 8
Joined: Thu Mar 22, 2018 8:45 am

Re: Fiberglassing the stems

Post by Rockford »

Many thanks for posting the picstures Jim and Brian. This is my 1st. fiberglassing experience, so the pics. are a great help. I didn't have fiberglass pieces long enough so I used 3 short pieces. This made for more scraping however using the carbide paint scraper, it was no trouble.
Would have been better to order a longer roll of fiberglass to cover the stems. I decided not to use what I left on the roll I have for fear of running short on the inside of the hull. Thank you for your advice guys.

Andy,
Rockford MI
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