Glass-covered plywood V-trough house gutter ?

Fiberglassing over plywood and one-off fiberglass methods. See: "Boatbuilding Methods", in the left-hand column of the Home page.

Moderator: ttownshaw

Miche
Posts: 3
Joined: Thu Oct 31, 2013 5:31 pm
Location: Salem MA

Glass-covered plywood V-trough house gutter ?

Postby Miche » Fri Nov 01, 2013 12:20 pm

Can I ask here about constructing a fiberglass-covered plywood V-trough house gutter---not a boat ? If not, anyone know where ? Thanks!

gdcarpenter
Posts: 1355
Joined: Tue May 05, 2009 12:18 pm
Location: Raleigh, North Carolina

Re: Glass-covered plywood V-trough house gutter ?

Postby gdcarpenter » Fri Nov 01, 2013 1:47 pm

If you are just looking on how to fiberglass a wooden gutter you want to make look under the "Fiberglass" section of "Boatbuilding Materials" on this forum to give you an idea of how to fiberglass wood.

I was a professional carpenter/GC for years so I'm just curious if you are doing an "Historical" renovation.
This is my first, last and only boat build.

http://www.gdzipbuild.blogspot.com

Miche
Posts: 3
Joined: Thu Oct 31, 2013 5:31 pm
Location: Salem MA

Re: Glass-covered plywood V-trough house gutter ?

Postby Miche » Fri Nov 01, 2013 2:39 pm

I'm no carpenter/GC, just a 'handy' homeowner and woodworker. The house is a post-war 'Cape Cod', with the top lip of the gutter 9.5 ft. above grade. It's not a 'historical reproduction', but I would want the new gutter to look 'olde-fashioned'. The present gutters are the common (for these parts) wooden milled ogee kind, with a joint in the middle, sloping off to each end.. My idea is to mount a one-piece 40ft. gutter level to the house, but with a sloping floor from one end to the other. It would then all run straight off one end into a downspout structure, not through a hole. The gutter drainage will be onto the driveway and then the street, for the front. And 10ft. out onto the lawn under a low deck for the back. So I'm not concerned about debris filling up underground places. The whole thing is this: how to minimize maintenance, and maximize the ability of the gutter to self-clear of leaves, twigs, etc. By finishing the glass/epoxy very smoothly, and giving it a periodic auto-waxing or Teflon spray, I think it would all work. But I'm ready to get shot down, if someone can. Thanks!

User avatar
galamb
Posts: 811
Joined: Sat Jan 17, 2009 1:37 am
Location: Inverary, Ontario - Cuddy Sport (modified)
Contact:

Re: Glass-covered plywood V-trough house gutter ?

Postby galamb » Fri Nov 01, 2013 6:54 pm

The glass/epoxy would certain work to keep the wood from rotting etc BUT epoxy quickly breaks down in sunlight so you would have to paint it or varnish it to protect it from UV rays. (marine epoxy is just a thermoplastic (BPA))

That would add a regular item of maintenance to your thought process here. Especially since it would be totally exposed to the elements.

You could go over the epoxy with a 2 part linear polyurethane paint or varnish which would last a good few years (maybe 5 or so), but it still would require periodic recoats and is expensive (compared to just about every other paint/varnish).

Alternately, there is some marine "bottom" paints (not anti-fouling) that are two part epoxy paints with teflon (for painting the bottoms of racing sailboats etc), again, run about 120 bucks a gallon, but that would protect the epoxy and give you the slippery surface you are looking for as well. Again, will break down every few years and require maint.

That's your options as I see it. Not sure if I would personally sink that much money into a "gutter" - the epoxy, cloth and paint are expensive.
Graham

Yes, Plywood is "real" wood :)

A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it :)

Miche
Posts: 3
Joined: Thu Oct 31, 2013 5:31 pm
Location: Salem MA

Re: Glass-covered plywood V-trough house gutter ?

Postby Miche » Mon Nov 04, 2013 3:15 pm

How much expansion/contraction can I expect from my one-piece 40ft. run of glass-covered plywood gutter ? This would effect how I attach it to the house.
-------------------
Do successive coats of epoxy or epoxy/glass bond strongly to each other just with sanding? Is there a time limit for a good bond?

User avatar
galamb
Posts: 811
Joined: Sat Jan 17, 2009 1:37 am
Location: Inverary, Ontario - Cuddy Sport (modified)
Contact:

Re: Glass-covered plywood V-trough house gutter ?

Postby galamb » Mon Nov 04, 2013 3:41 pm

Depending on the temperature and the brand of resin and speed of the hardener you are using you can "over coat" without sanding.

There is a term used with epoxy called "green" - that's when the epoxy has set up but it's not cured yet. So at say 70 degrees with a medium to fast hardener the epoxy may be green from 8 to 12 hours after initial application. At that point it's still chemically reacting and an over coat at that point will also "chemically bond" to the green epoxy.

(edit to add - if the epoxy feels (dry/just past tacky) but you can still dent the surface with a fingernail it's "green")

After about 24 hours the epoxy is cured (although, again depending on brand etc, it may continue to cure for up to maybe 7 days) and must be sanded so the successive coat will mechanically bond. Generally 80-120 grit sanding is sufficient to give the next coat something to "bite" into.

If you totally encapsulate the wood you are using (so minimum of 3 coats on all sides) it will stabilize the moisture content of the wood and expansion/contraction will be quite limited. Essentially, if your coating is "total" (or as near as you can get) your wood is encased in plastic - no moisture in or out means minimal swelling, twisting, warping etc (which is why "marine" epoxy is so successful on wooden hulled boats).
Graham

Yes, Plywood is "real" wood :)

A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it :)


Return to “Fiberglass”

Who is online

Users browsing this forum: No registered users and 2 guests