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amhacker22@hotmail.com
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06/10/2009 09:28AM  
Hello.

I've got a Prospector that was the class boat from NW Canoe this winter (I won the draw!!). I'm real happy with its construction and have taken it out on a couple of trips this year so far. Its a great boat.

My only complaint is that the fiberglass/epoxy finish looks kind of uneven and a little cloudy in spots. I notice that when it is wet the cloudiness disappears. I'm wondering if it is too late for me to sand it a bit and add another layer of epoxy. If I do this will it give it a smoother and more transparent look, or will it just add to the cloudiness?

I'll try and add some photos that illustrate what I'm talking about, but its been pretty hard to do so far. They never really show up.

Thanks a lot!

-Nick

P.S. I've got my forms finished for building a 17 ft "Susie B". Its basically a stretched out Bob's Special. The Bear Mountain plans came with the conversion instructions. I'm psyched and will ad updates as the project continues.
 
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Woodbender
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06/10/2009 01:21PM  
Nick - if you could post some photos before it's wet then while it's wet, it may help to see what is going on.

The short answer is yes - you can add epoxy after the fact. You can scuff it up a little and roller it on for being even and then tip it with a brush depending on the viscosity.

Has the canoe been varnished at all? Almost sounds like you're dealing with an epoxied hull with no varnish. If the weave of the fiberglass is completely buried you probably don't need to do another epoxy coat. Meaning the epoxy is doing it's job if the cloth is covered and properly filled.

This is interesting - please keep us posted.
 
amhacker22@hotmail.com
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06/10/2009 07:24PM  
There is no varnish on the hull. I hadn't planned on varnishing. I think the problem may be that the weave is not completely filled in. You can see some parts where there is more coverage and the wood comes through more clearly. You can actually see that these spots are in the shape of the spreaders we used to spread the epoxy. The weave is much more visible in the cloudy sections. My thought was that filling in the epoxy more completely would fill in the gaps and bring out the wood more clearly.

Thanks a lot for responding. I'll try to get some pictures to give you a better idea of what I'm talking about.
 
Woodbender
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06/10/2009 08:17PM  
You will need to do a couple things then.

Before adding another layer of epoxy you will need to smooth out (probably with a scraper) the shapes left behind from the squeegees (spreaders) that were used. Adding another layer of epoxy with not get rid of those ridges. Then you will need to completely fill the weave of the cloth.

Also with these strippers which are epoxied they really must be varnished with a good exterior grade UV protection varnish. At least three coats inside and out. If you do not varnish these fiberglass and epoxy strippers they ALWAYS cloud. Epoxy breaks down in Ultra Violet light and turns cloudy. Always.
 
amhacker22@hotmail.com
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06/11/2009 07:04AM  
Tim,

Thanks a lot for the advice. I'm heading into the BWCA this weekend, but will probably get started when I return.

One more question. If I decide I can live with the bumps and the uneven portions left by the final epoxy layer and don't sand it down, will the addition of the varnish mitigate the cloudines that is already present? Like I said earlier, when the boat is wet it looks great and I am not really bothered by the uneven texture. If the varnish will recreate the wet appearance then I might skip the extra work and weight of another epoxy layer. Frankly I'm kind of anxious to get started on the new boat.

-Nick

P.S. Any particular varnish brand/product you prefer over another? I've got no experience with any of them.
 
Woodbender
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06/11/2009 07:23AM  
If you have a decent scraper (like a Pro-Prep or similar) the epoxy ridges will scrape down quite nice. Don't scrape your fiberglass though unless you have a nasty fold popping up.

My thinking is if it clears up when it gets wet you may be in luck.

Note from personal experience; varnish is very unforgiving about what's underneath. If you want a smooth finish the epoxy must be smoothed out then finish sanded. No bumps and no ridges. Varnish is NOT a filler like epoxy is. It perfectly conforms to anything which is underneath.

If you have glass which is not completely filled then it's not doing it's job. Just as steel reinforcing rods must be completely surrounded by concrete, fiberglass must be completely surrounded by the epoxy.

Now here's a bravery test - when you sand the epoxy before the varnish it WILL get scuffed and cloudy and you'll think "oh god - NOW what did I do?". But it's all normal. When the varnish hits it it's all beautiful.

Varnish;
You ask three builders and you'll get three different answers. Your varnish MUST have UV inhibitors. But I have used Coma Berenice with good results. Goes on easy and coats well. For the Freedom17 I am building right now I'm going to try Z-spar Captain's Varnish by Pettit.
http://www.jamestowndistributors.com/userportal/show_product.do?pid=100&familyName=Z+Spar+Captain%27s+Varnish

Our son is interning this summer at a Classic and Antique Boats restoration shop and it's all they use.

Good luck to your endeavor!

 
Cedarboy
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06/11/2009 09:45AM  
AmH
Do not use a scraper, just sand the hull out with 150 Grit. You chance gouging the hull with the scraper. Sanding will give you trhe smoothest surface. You can apply another coat of epoxy with NO problem.
Better yet just give Dennis or George a call about this, any more layers you put on are purely cosmetic not structural and will add weight.
If it were my boat I would just sand it up with 150 smooth then put a couple coats of Minwax Helmsans Spar Ureathane for the UV protection. Light sanding between coats. I know your boat(I am a regular coffee drinker at the shop and addictive customer)it has enough epoxy, just sand and urathane.
CB
 
Woodbender
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06/11/2009 10:15AM  
Sounds like Cedarboy is yer man. If he's seen the boat first hand go with what he says! I'm guessing at best on this side of the monitor.

Good luck and let us know how things go for you!
 
amhacker22@hotmail.com
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06/11/2009 10:27AM  
Thanks Guys. I'll be sure to post some before and afters.
 
Woodbender
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06/11/2009 10:42AM  
Cedarboy - what are your reviews on the Minwax Helmsman Spar Ureathane? Good flow out and wet edge workability? I've not used that one yet.

Do you roll that out and tip it off?
Sponge brush?
 
Cedarboy
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06/11/2009 03:55PM  
Woodbender
I have had great luck with MHSU. Very durable and hit it after a couple years and enough scratches, it looks like a new boat. I put dark green tint into it this last boat, and now I have a translucent green stripper. Outside only, inside still clear natural.
I use a sponge brush and 3 coats,lite sand between. I have known some builders that spray it on, with good luck.
Best of all any Menards or Home depot carries Minwax products
CB
 
Woodbender
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06/11/2009 04:12PM  
Cedarboy
??? You added a tint ???

Intriguing - how did you do that?
Is Minwax the manufacturer of the tint?

Did it produce a transparent forest green which let the wood grain show or did it produce a milky translucent dark green?

Can you post a pic? I'm genuinely interested to see how this turned out.
 
Cedarboy
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06/12/2009 10:40AM  
Went to Sherwin Williams, told them what I was wanting to do,bought some tint from the mixing machine they use. They said not to use more than 2oz per gallon ratio, so it would dry properly. Yes it is a dark green translucent green, strips show through.
The reason I tried it was I had gotten some milkey epoxey last fall when I glassed the outside. Temps were to be in the high 60s, but they went down into the low 50s and rain when I was half way into the process, weatherman was wrong. So it gave me an opportunity to try something new, am very pleased with the results.
Worst case I could always sand it off and start over.
CB
 
amhacker22@hotmail.com
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06/24/2009 08:36AM  
Just an update...

I sanded and added 3 coats of the Minwax spar varnish to the canoe and it is fantastic. It gave the canoe the finish I wanted and eliminated all but the most memorable scratches from the hull. I can't thank you guys enough for the great advice.

-Nick
 
Woodbender
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06/24/2009 08:44AM  
AWEsome!! Hey you got pics??
 
amhacker22@hotmail.com
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06/25/2009 08:07AM  
Here is a before and after. They don't show the significance of the changes real well, but they do show how nice it looks now. Before...
...and after.
I'm hopefully going to do the inside today and tomorrow. Maybe those will show the changes better.
 
Woodbender
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06/25/2009 08:16AM  
Real nice outcome. That'd be a pleasure to paddle anywhere.

Ya' done good Nick.
 
amhacker22@hotmail.com
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06/25/2009 08:20AM  
These might show the difference a little better.

 
cheesehead
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06/26/2009 08:54PM  
looks nice. why no outer stem?
 
amhacker22@hotmail.com
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06/27/2009 03:39AM  
There is no inner or outer stem on this boat. That's just how they build them at Northwest Canoe, where I took the building class. I can't remember for sure if we discussed it, but I thought they said that the strength of the stem came from the fiberglass/epoxy and that separate stem pieces were extra work and extra weight. (I may have actually read this in the Gil Gilpatrick book too. He uses the same technique. I'm not sure exactly where I got this from.)
You can read about this technique in a free download at their website.
Here's a link: Northwest Canoe Free Download
 
Woodbender
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06/27/2009 07:04AM  
Hi Cheesehead - I also built a Northwest Canoe plan (38 Special).

When I talked to Al Gustofson he maintained that the inner outer stem construction was a typical (and historically newer) style from the Eastern states and Canada. There obviously are other building styles with their pros and cons. My take is - if it floats and has a fair hull and moves well in the water - it's a good build.

Al's big sermon was drilling into the outer stem to nail a brass stem band to "protect" the hull was (in his thinking) ludicrous. Wood and metal expand and contract at different coefficients of expansion and nail/screw holes in the outer stem will only get bigger and permit water to get into your hull that you've spent so much work on.

My personal take on an inner outer stem design (from a structural design person's view) is it seems to be an open joint relying on glue to hold strips to the side of the inner stem. In this position the strips can be under a lot of twisting and springing stress load. The outer stem obviously caps that whole structure so maybe that is the saving grace there.

Personal mileage may vary.

For our Freedom 17 (plans via Canoecraft & Steve Killing) I am using an inner stem for this build but using an outer finger joint preferred by Northwest Canoes. I believe it is a stronger joint. The finger joint style wraps a couple layers of cloth (bias cut) at the immediate bow and stern so that protects things quite well and there is a fillet of wood flour thickened epoxy inside the hull to back up that joint. It's really quite strong.

The argument I suppose is "what if you bash a rock - wouldn't the outer stem protect the canoe?" Yeah I suppose. But letting an 8 year old niece or nephew ram a shoreline should not even be done with an aluminum canoe. And we bashed a couple rocks last summer in Crab Lake (EP04) She held up just fine.

Both styles of construction have their merits. They're just different.

Have a great build!



 
cheesehead
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06/27/2009 04:56PM  
ok i might have missed it, with no inner how do you hold the strips before the epoxy? just glue and staple to the station?
 
Cedarboy
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06/27/2009 05:30PM  
yes
 
Woodbender
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06/28/2009 01:15PM  
"ok i might have missed it, with no inner how do you hold the strips before the epoxy? just glue and staple to the station?"

Pretty close. For our 38 Special we shaved the station mold to mimic an inside stem shape and varnished it to keep the glued strip from sticking to it. (packing tape works as well)

We DID staple to the stem form. We did NOT glue the strips to it. Once the glue dried we could take off the clamps (if it needed clamps) and it held it's own just fine.
 
cheesehead
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06/30/2009 10:16AM  
i also do the packing tape trick. what a difference it makes.
 
Cedarboy
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07/16/2009 10:27AM  
I always use masking tape over the forms to keep from gluing as dicussed. But now I will try the heavey duty aluminum foil tape on the stem forms. Guys at NWC are doing this with great results, stems pop right out when pulling off the forms. You could do this on the other forms insteda of masking tape but the only forms that have been hard to get out were the stems for me anyway.
CB
 
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