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Greg Johnson
04-04-2009, 11:56 AM
I was just reading the "Strip Built Kyak" thread and it inspired me to post this question. I have the mast off the first boat my dad built in my front yard as a flag pole. I usually refinish it every couple of years with a marine spar varnish. This past year I was thinking that perhaps I should think about fiberglassing it, for strength and durability. I worry about being gone and a sudden wind storm coming up. I don't want it to snap in half. I usually take the flag down when it blows hard.

So, now I expose my lack of knowledge....:o. I have never used fiberglass for anything other than structural integrity. This flagpole is a beautiful clear spruce that is about 75 years old. I don't want to botch this and ruin the look of this piece. So, what type of resin and glass would you recommend and what is the best application process? I am also concerned about how to stage it for finishing. If I lay it down horizontal I am afraid that I would glass in a permanent bend in it. It's about 25' tall, so I was thinking I could stage it vertically up against the house and work off ladders.

I am open to all ideas and suggestions. We do live in an area that gets some significant wind. My other hobby is weather and I have a weather station and web site: http://www.SkunkBayWeather.com . I center the flagpole on my webcam for a good perspective of the current conditions. I also have a spotlight on it at night so we can always see it. This is a VERY sentimental piece for me and I want to do it right.

Thank you in advance,
Greg

John Messinger
04-04-2009, 4:34 PM
I would set it up on a "strongback". A strongback is a rectangular framework cobled up from 2x4's. Pull a string very taught, down the center of the strongback and from this you can get side-to-side straightness from this. Use a cheap laser pointer to set some nails at intervals to check for sag. The Gougeon Brothers book on using West System Epoxy for boat building describes strongbacks better than I can. I would use epoxy resin and 4 oz cloth which you can get as tapes.

Travis Schafer
04-04-2009, 9:36 PM
After setting if on the strongback I would use whatever cloth you wanted (4oz sounds good) and lay it over one half of the mast. Then I would mix straight West System epoxy (no fillers) to wet the glass out. After that cures, I would flip the pole over, and glass the other half. There are numerous ways to make the two glass halves to meet and that is another story altogether.

Once you have your glass cured and cleaned up, I would use some fairing filler with the West System(410 or other) and give it one coat over to fill the glass texture. Sand and repeat if necessary to a smooth finish.

Some thing to consider- this will stiffen up the mast and possibly cause some faults under heavy winds (cracks) as you will loosed some of the woods flexability. Make sure your glass cures against the wood, any bubbling of the glass could allow moisture to build up under the glass(not good) Also, the 410 is a brown fairing compond, so if you want to keep it the same color, you may need a different kind of filler.

Robert Meyer
04-04-2009, 10:21 PM
However you fiberglass your flag pole, remember that epoxy absolutely must not be exposed to UV rays or it will degrade quite rapidly. You must block the UV with a varnish or a coating made for this purpose. These coatings vary in their protection so some research as to their UV blocking abilities would be in order. Some imported UV blockers claim three years between re-applications on boat bright work.

Greg Johnson
04-05-2009, 11:44 AM
Thank you all for your responses. Just as I suspected.... I have a LOT to learn :o. I had been thinking about the problem with stress fractures due to flex. That would probably be enough to keep me from doing this with glass. This brings me to the question, is fiberglassing a wood sailboat mast an acceptable practice? This was basically my idea that I came up with.... and that can be a little dangerous :rolleyes:. I have never seen this, although I haven't been looking either. I am not a sailor, so I won't even try to think I know much in this area. I would think if it works on a sailboat, it would definitely work as a flag pole. I do have stays from the original rigging about 2/3 of the way up the pole, so it is only the top third that flexs.

The other thing I was totally unaware of was the UV issue. That sounds like I could be getting myself into a maintenance headache. Perhaps good ole Marine Spar Varnish is my best solution.....

Thanks again,
Greg

Mac McQuinn
04-05-2009, 7:12 PM
Greg,
I would give Gougeon Brothers a call on their tech line. These guys have tons of epoxy experience with their West/System product and on top of that, they know sailing from canoes to large stuff and the way to keep things from breaking.
Good Luck,

Mac

Greg Johnson
04-06-2009, 12:55 AM
Thanks Mac. I'll give them a call.

Greg

Frank Hagan
04-06-2009, 1:17 AM
Epoxy is the only resin I'd recommend, and it does need to be protected from UV. so you will be varnishing it every year anyway.

4 ounce glass will nearly disappear, allowing the wood grain to show through. It will be hard to apply the glass to the round spar, but they do make "socks" or "tubes" that you can buy for masts (although I have seen them more often in carbon fiber, which is much stronger but gray or black in color).

To be honest, I don't know how much strength you'll be adding with light enough glass to let the wood show through. I would be hesitant to glass it at all; spruce masts lasts for many years on boats.

Greg Johnson
04-06-2009, 9:39 AM
Frank,
That is definitely where I am leaning. The "cost/time/benefit" analysis of this project is starting to become clear. A quick coat of varnish every now and then may just be the best solution.

Thanks,
Greg

Travis Schafer
04-13-2009, 9:47 PM
Oh and to repsond to your question, no, it is not common to glass wooden masts on sailboats.

John Messinger
04-14-2009, 8:48 AM
That is a beautiful weather website you have put together, Greg. Alas, I am in the Northeast.

Greg Johnson
04-14-2009, 9:02 AM
Travis,
Thank you for your response. It seemed like a good idea when I thought of it.... but whenever I think of something and have never seen it done before, I know it is worth looking in to more deeply.... before I get myself in trouble :rolleyes:.

John,
Thank you for your kind words. It has evolved into a very fun hobby. We are located in an area that has lots of weather and I enjoy watching it wherever I am. That's really why I put up the website. However, just before I got my Davis station, I watched a 60ft. fishing boat capsize in front of our place during an unpredicted northerly that hit like a bomb. I have a link to the story on my website. I then realized that if I could provide current conditions to boaters in my area, it would be a good service to provide. The point that is behind the flag in the webcam photo is called "Foulweather Bluff". There are more than a few vessels at the bottom out there. Actually, about 10 years ago there were some treasure hunters diving out there looking for a ship wreck from around 1900 that was supposed to have some valuable cargo. They were unable to locate it because the currents are too strong out there.

Oh... and we refer to our area as the Pacific North Wet....:)

Greg