pinoyboats.org forum

Dr. B · Mate Joined: 08 Jul 2010 Posts: 5 Location: Butuan

Hi Folks. I just discovered your site and I'm hoping to tap into your collective expertise.

I am currently building a wooden 13' sailboat called a "Dart" from plans I got from http://www.svensons.com/boat/. This site has several plans collected from old magazines. My guess is that the "Dart" plans were published in the 1960's

I've got a couple of problems relating to the mast, sailtrack and slides.

The mast is supposed to be constructed of sitka spruce. It is 1 3/4" x 3 3/4" and is constructed of two 3/4" x 3 3/4" x 18' and two 1/2" x 3/4" x 18' glued together to form a hollow rectangle in cross section. The plans call for 5/8" sailtrack.

Question 1--Can anyone recommend a type of wood (of similar weight and strength to spruce) that is available here in the Philippines?

Question 2--Does anyone have any suggestions about the design and fabrication of the sailtrack and slides?

Thanks in advance for any help you can provide.

pinoypiper · Posted: Thu Jul 08, 2010 10:01 pm Post subject:

Welcome aboard Dr. B.

Wow! you're building a dart. with a rabbeted bow stem... nice....

You can go with what you can find at your local lumber yard, red lauan or tanguile should be fine, just select really nice pieces, no knots, bukbuk bore holes etc... avoid woods that are too heavy like yakal. trust me you won't want a heavy mast.

will you be sewing your own sails? or buying them?

If you're buying, Hyde in cebu sells external slides. you can use aluminum or ss flat bars for a mast track. check the projects section and look for teddy's sprinter for details.

maligno101 · Posted: Fri Jul 09, 2010 12:19 am Post subject:

Remember to put a filler block inside the mast where the stays are attached.

Good luck on your build and take time to post pictures!

Dr. B · Mate Joined: 08 Jul 2010 Posts: 5 Location: Butuan

Thanks for the suggestions. The internal block at the stay connection points is a great idea--and one I would not have thought of. I'm having difficulty finding 18' lumber so I'll probably try staggered scarf joints and use 12' lengths. I'm also having difficulty getting 5/8" x 12" x 14' lumber for the sides but I think I'll eventually be successful.

I'm buying sails from Hyde and it turns out that they do sell external slides--although it took a month to get this information out of them. For reasons that are unclear to me my emails go to a guy named Wooderz in the UK and he doesn't seem to be up to speed on what is available in Cebu. Anyway that will get worked out.

Now the current problem--the canvas covered deck and bottom. Because I am a neophyte I did not recognize at the outset that this process is out of date. I did find that there is a company called Fosters that sells CHIL-SEAL CP-50A MV1 which is a lagging compound that looks like it would be perfect (and it's cheap) but....they only ship to US addresses.

I think that there are several locally available coatings and adhesives that should work but I'll have to experiment on scrap material to figure out what's best.

On the other hand I don't want to reinvent the wheel. Is this a problem that someone out there has already solved?

I appreciate your help.

punzalane · Posted: Thu Jul 29, 2010 9:34 pm Post subject:

Happy building Dr. B Smile

pinoypiper · Posted: Thu Jul 29, 2010 10:59 pm Post subject:

punzalane · Posted: Fri Jul 30, 2010 6:58 am Post subject:

The Dart reminds of Kameda's boat...one difference is the centerboard in Kameda's...

and yes, Kameda used 200gsm cloth and epoxy resin for the entire hull.

I'd second piper's suggestion Smile

maligno101 · Posted: Fri Jul 30, 2010 8:27 am Post subject:

If I were building the Dart and didn't have access to epoxy resin and fiberglass cloth, I would do what the old pro builders did:

- Use hardware epoxy glue (like Pioneer brown, NOT marine) throughout.
- Skip the canvas or fiberglass sheathing and use hardware epoxy glue thinned-out with lacquer thinner to watery consistency to coat all the surfaces.
- Paint all the surfaces with outdoor enamel paint.

I have a 20+ year-old boat to show this system works.

Dr. B · Mate Joined: 08 Jul 2010 Posts: 5 Location: Butuan

Hi Guys--

This is turning out to be a fun build for me. I had no idea how challenging the project would be. First off I find that my T-square is pretty much useless. Right angles are almost nonexistent. It's a really good practice in joinery.

I'm still considering my options for the deck and bottom. It would be nice to stay close to original plans. One idea I had was to mix epoxy and a lacquer based paint to make the adhesive undercoat. I've used this concoction in the past as a waterproofing coating (but not as an adhesive) and it worked well. But I never used marine epoxy. What's the difference? Why is marine epoxy not a good choice?

Thanks for your suggestions.

B

[quote="maligno101"]If I were building the Dart and didn't have access to epoxy resin and fiberglass cloth, I would do what the old pro builders did:

- Use hardware epoxy glue (like Pioneer brown, NOT marine) throughout.
- Skip the canvas or fiberglass sheathing and use hardware epoxy glue thinned-out with lacquer thinner to watery consistency to coat all the surfaces.
- Paint all the surfaces with outdoor enamel paint.

I have a 20+ year-old boat to show this system works.[/quote]

pinoypiper · Posted: Fri Jul 30, 2010 10:43 pm Post subject:

maligno101 · Posted: Sat Jul 31, 2010 12:03 am Post subject:

Sorry, I may have presumed too much. So if we go back to the specs of the Dart, it says:

2 lbs casein glue
1 pt marine glue
1 gal canvas cement

Casein glue is made from milk and was available as powder. This was dissolved in water to form paste. (Pour a bit of milk on the table then put a piece of paper on it. If you leave it until it dries, you will see how good a glue it is.)

Marine glue is not defined in the article. This may have been resorcinol glue like Weldwood.

Canvas cement is for spackling canvas tape used to cover the joints of plasterboard walls.

Now will you want to use these materials today? Even if you can find them? Rolling Eyes

But seriously, the main reason you will want to use epoxy and fiberglass is because they far superior to any of those materials. Epoxy glue is also very forgiving; you don't need to make your joints as perfect as cabinetry--you may not even need to rabbet the stem! Casein and Weldwood must be applied as thinly as possible because they are glues don't have strength by themselves and require close-fitting joints. Epoxy when properly applied is stronger than the wood itself.

As Piper explained, "epoxy" comes in different forms. To summarize in simple terms (Doc Punzalane can give a much more detailed analysis):

If it's clear it's pure resin. In wooden boatbuilding this is generally used to "encapsulate" the wood--it is painted on raw wood to form a waterproof barrier. It is also used when sheathing wood with fiberglass cloth--it impregnates the cloth and at the same time bonds it to the wood.

If the epoxy is colored and or opaque, it's loaded with fillers and additives to modify it's characteristics. E.g. brown epoxy is a general-purpose glue; "marine" is thicker formulation that doesn't drip as fast; metal-high-temp for sealing radiators; etc. etc.

In a way, then, epoxy has simplified our lives as wooden boat builders. In it's various formulations, we can select (or make our own formulation, as Lncc and others can attest) what will serve our needs.

Sorry for the long post but hope this helps in getting you started on your build.

Dr. B · Mate Joined: 08 Jul 2010 Posts: 5 Location: Butuan

Sorry Guys I guess I was not very clear.

I agree that epoxy is the best choice for all the joinery.

The concoction I cited was an option I was considering for the "stick-um" for the canvas--since canvas cement is no longer available. You folks have, however, pretty much convinced me to abandon that route.

But I still have a question about the following:

arvin555 · Posted: Sat Jul 31, 2010 11:43 pm Post subject:

Better wait for Maligno to reply.

But I imagine the reason why we don't suggest Marine Epoxy (hardware store bought) is because they are usually filled with a lot of Fillers, so basically in our opinion they are more of a kind of "putty" than laminating epoxy, worse are those Non Sag ones. The Brown Epoxy you can get sometimes in stores, at least does not have fillers or not have too much, and they are at least epoxy resins only and not "putty". What it means is that it is more easily absorbed by the wood and thus will help bind your wood better than putty.

A good experiment, you don't have to do it, is to put a globe of Marine Epoxy on a piece of wood, and put a few drops of brown epoxy on a separate area. Then after they are cured try to pry them out with say a screw driver or a scraper, see which one you can scrape easier and you scrape more off. Chances are it's the "marine epoxy" that will be easier to scrape off. Which means it did not bind well with the wood.

TTFN
Arvin

pinoypiper · Posted: Sun Aug 01, 2010 6:46 pm Post subject:

arvin555 · Posted: Mon Aug 02, 2010 12:50 am Post subject:

My summerbreeze needs to be repaired (still) and the area that needs to be repaired was.... surprise surprise, glued together with Marine epoxy because I ran out of Laminating Epoxy during the build, the rest of the boat held very well. So for me, for filleting and stuff, I still go for Laminating epoxy plus filler, heck I used wood flour.