Thread: Goat Island Skiff questions...

Warf, I'm here in the 'States and am just starting on a GIS. Get a metric tape and rule, build it in metric. It actually is simpler than fiddling around with imperial fractions. Why we are still using the old system here, I can't figure

Originally Posted by warf

New guy here, found this excellent forum last week and am impressed with the content.

A little about me first. I have build many boats over the years from V drive ski boats to a 26' sailing cat, both frame on construction to stitch and glue, have a lot of sailing in my background from racing to cruising all in salt water.

Now for the questions about the Goat. About ready to order the plans and was wondering if they are available in feet/inches for us yankee's or just in metric?

I like the idea of the hollow mast but as 95% of my sailing is done solo am looking to get the boat less tender with less weight aloft and am thinking about a aluminum round mast (Gasp, choke!) Would there be any weight savings going this way, if so what diameter and wall thickness would work well?

Also in the pictures of the goat I notice a chine log is used on the side panels to fasten the bottom to. Can the bottom/side attachement be done the stitch& glue method with the usual epoxy fillets and glass tape instead? Just trying to save a little work on my part, I think the weight/strength would be about the same either way. Whatcha think?...warf

Warf, Welcome aboard, mate. (I said mate and I'm a yank...starting to pick it up)

I strongly recommend going with the chine log construction. Having built a couple dozen boats this way and a handful stitch and glue, I am totally convinced that, done right, the chine log is as strong for the weight, looks more traditional, and is more enjoyable to build. The feel of planing that chine down with a sharp plane cannot be beat. The look make us remember it is a wood boat. The strength to weight ratio difference is insiginificant, though I have not done any empirical tests. Follow MIK's plans...they are excellent and his rationale and cleverness is hard to improve upon.

I have to impose my opinion about the mast. Please, please, please build a wood mast. And make the birdsmouth mast. If you have done some boats and plan to do more, it is one of the best techniques you can learn. It is a little intimidating at first, but after the first project it makes tons of sense. The result is a very light mast. Is it as light as the ugly, aluminum stick? I do not know. Is it nicer to look at. YES! Will you be more proud with the wood mast? YES! Will you go slower with the wood? NO!

All the best! I'v done several birdsmouth masts and would be happy to post while I make mine for the Goat. I'll post to the thread on the birdsmouth.

Cheers,
Clint

Could you make a second set of staves for someone else Clint?

Welcome Warf!

Actually MAM was able to find a tapered flagpole that was about the right size for his goat (think it was about 18lbs - we had a discussion somewhere on this forum). The wood is much nicer of course. I don't know if the birdsmouth would match that, but I would be guessing you could get close. Also an untapered alloy mast would look terrible.

The problem with aluminium sections is you are really stuck with what is actually available and often cannot find something that is ideal. The diameter would have to be around the 87mm mark (same as the wood mast) probably with a 2mm wall - or something thinner with a sleeve in the bottom metre and a half (cut off at an acute angle at the top to prevent a stress concentration). A bit smaller might work OK too - I can run the calc if you find some likely sections.

As far as a composite chine - I chose wood because many home builders don't have the skills to get a really nice fair and crisp join along the chine using stitch. But it always works with wood. The sides attach to the bulkheads/stem/transom and then the bottom panel is drawn up a bit oversize screwed down and trimmed down to match the bottom after it is glued on. It does look nice and woody and fits in with the bulkhead structure and framing too.

I think you would be well capable of working out those details for changing over to a fillet by the sound of your experience Warf.

MIK

Thanks, I think your right that a untapered metal mast would look to much like a power pole along the highway..lol..Guess I will worry about the bottom attachment when I get to that point. I found it's pretty easy to get nice epoxy fillets if you make up some flexable plastic spatchula's that are the shape you want and use walnut wood flower to thicken up the glue, color matches pretty fair for most mahogany plywoods and is like smoothing out peanut butter if mixed right. Thanks for the fast come back on my post, you have a great site here, keep up the good work....warf

MIK, I could do staves for folks glued up or not (I am cutting staves any day now. I plan to glue them up so that they don't get too warped sitting around). I'm in the middle of being swamped by people who want Shellback Dinghies....wanting Goat orders!

I'd love to get the exact # from MAM and try to get the B'mouth mast that light. I bet we can do it!!! Nice to have a target.

Off to work....

Clint

My mast ended up right at 20 pounds, with the ends sealed, hardware installed and two coats of paint. The pole is only 3 inches in diameter tapering to 1 7/8 with a .125 wall thickness--overkill in my estimation*. I did not reinforce the butt end.

I toyed with the idea of faux graining it, even going so far as to buy the paint and graining tool. I might do it someday but right now I'm happy with the aluthane paint I used.

*Estimation based on the poles I had on my Gazelle--44 feet long, 8 inch tapering to 3 1/2, .187 wall thickness. The junk sails were 400 sq. ft. each and I had a bury of about 12 percent on each. After years of sailing and several accidental stress tests I was a true believer.

I've built two plywood boats, the first s&g (a pirogue) and the second was the Goat, with chines. I like chines better for several reasons, the main one being the finished product will be more true to the plan. With s&g the final shape and size of the bottom is happenstance; it will be very difficult to get fair curves along the joint.

Originally Posted by warf

I like the idea of the hollow mast but as 95% of my sailing is done solo am looking to get the boat less tender with less weight aloft and am thinking about a aluminum round mast (Gasp, choke!) Would there be any weight savings going this way, if so what diameter and wall thickness would work well?....warf

This will make up your mind about aluminium masts (Note spelling Yanks!) Doesn't this look SO WRONG?
[ame="http://www.youtube.com/watch?v=1yRznzfYl9g&feature=related"]YouTube - Kokako Core Sound 17[/ame]

Originally Posted by woodeneye

This will make up your mind about aluminium masts (Note spelling Yanks!) Doesn't this look SO WRONG?

If anything, aluminium looks even worse on a wood boat than aluminum
To each his own, I suppose, but certainly not my cup of tea.

I think aluminium can be positively beautiful--on any boat. I had a sitka spruce mast on my Dovekie and, in spite of annual varnish work it died a slow death. When I moved aboard my Gazelle I "gave" the Dovekie to my sister for safe keeping. The mast cover was lost and the mast was exposed for 3 or 4 years without any maintenance. When I retrieved the boat the mast was DOA.

Here's the pole I used for my Goat: http://www.united-states-flag.com/cpecss15s.html

It's a "15 foot" model but they don't include the 2 foot bury in their designations. Note shipping weight is 45 pounds but that includes all of the hardware you don't need. Once cut to length my bare pole was around 17-18 pounds. Once sealed up, painted and finished it floated very high when I tossed it in the river.

I must admit I do like nicely engineered masts in any material. I do like the cheapness of getting a good performance because of the shapeability of wood.

If I do some bigger boats I will probably go for aluminium masts depending on the stability and weight of the boat. The freestanding masts do have to become quite big and heavy in bigger sizes on any boat.

At some point the weight up in the air becomes such a problem that it makes sense to make the switch in some sort of definite way.

I was very glad that MAM was able to find a nice looking piece of alloy that was roughly the right size.

MIK