Thread: My Green Island 15

PLYWOOD< FRAMES < BOAT.

You have the sequence right,
and you have a fair hull, so I think all is good, I would sit the hull upside down on the saw horses to clean up the side scarf joints, and glass the Hull(you are going to glass to the gunnel right??).

I looked at this boat and the goat island skiff many years ago, but decided to stay with stink boats , as i and the family are more into fishing than sailing.

You have the basis of an excellent boat,and the workmanship is fine (better than mine) , keep up the good work, and don't forget to keep posting Pic's .

Jeff

GI15 is on my short-list of favourite designs.
Hope you will keep posting.
regards
AJ

Hey Jeff and AJ

Thanks for the comments. In response to your question Jeff....I am not glassing the bottom...shock horror! I spoke to Mike Roberts(designer) about that very thing a few years ago and he deemed it unnecessary for a boat like this. His manual goes into the option of taping the chines but he didn't bother on his original GI15 because he believed is made repair easier.
I had the fortune of catching up with Mike just recently while holidaying in Noosa. I was driving along the esplanade when I spotted a familiar hull shape on a trailer a few cars in front of me. I stalked the boat u tip they parked and low and behold the owner was Mike with the original GI15 built some 20yrs ago. It was a real treat to see it.

I will endeavor to keep the pics coming however I am at that horrible sand/epoxy/sand/epoxy/sand/fair/sand stage which makes for rather boring photos. It may pay to wait until I have the time to do 3 wet on wet coats of epoxy. Then I only have to sand once and fair and sand again.

Cheers

I know that Mike, said that it was not necessary to glass the hull, however after building 3 boats myself and speaking with the designer of my current boat (MANGROVEJACK3.65) also my brother in law , who builds for a living.

Glassing the bottom , or at the very least the chines is highly recommended.

the glass adds strength , abrasion resistance , and seals the plywood,also a good base for paint, and it really does not affect repairing any dings or scrapes.

Jeff

I can't argue with any of you logic

Is the mangrove jack the stick and glue run about? I looked at the plans with interest some time back but thought I'd better finish one boat before I started another.

HI andrew ,

Yes she is stitch & glue, and performs very well.

she is glass outside completely , and resin saturated in side, filled , faired , and painted,
attached some Pic's for you.

Jeff

She looks great! I like your work. What finish did you use? I am looking at paint products ATM and I am leaning towards Altek.

Jeff,

That Mangrove Jack is a sweet little boat. I bet it rides better than an equivalent size aluminium vee-nose punt.


Andrew,

Think I would go for glass on hard chines like that too. Might not be required structurally, but would offer better protection from knocks that might let water into the plywood end grain, unless you were particular about quickly fixing the inevitable dings on the chines. Owners of GIS's would have a view on this subject I reckon and there are plenty of them in this forum.


Cheers, Cameron.

Cameron,

Yes she does ride sweetly , no pounding at speed ,and no tinny slap at rest,and about 20 kg lighter than an alloy equivalent.

Andrew,

Finish is NOR Marine Enamel , but if l build again I will use 2PAk, as the enamel is not fuel proof, and not as durable as the 2 Pak .

Jeff

Ok now here is an interesting question for the more experienced.

I am making my spars out of hoop pine. Mainly because of availability and price. To get a stronger result for the main section of the mast I am laminating 3 strips together. I had in mind to put a layer of glass tape between the strips for extra strength. So my first question is....is that the best thing to do or am I better off leaving the glass cloth out?

Now while I was overseas I had the timber stored at my brother in laws house and he kindly decide to cut a meter or 2 off one of the lovely pieces of 4.2m hoop pine for the mast. Easy enough to buy some more but then while I was looking at pine I came across some lovely western red cedar. So I started thinking aesthetics and the possibility of using WRC as the middle strip of timber out of the 3 pieces to be laminated together for the mast. I know the reduced weight would be an advantage but I am concerned about the structural integrity....

So I would love to hear from those with knowledgable opinions about my two ideas.

Andrew,

I wouldn't worry about glass in the lamination of the mast, not necessary, If weight is an issue , you could make the mast hollow, .

Basically you would be building a box girder with timber, very strong but light, if you check a few of the building sites (GOOGLE) there should be instructions for hollow mast construction, just modify the dimensions to suit the GI mast .

A solid mast is starting to be a handful , and will be in any sort of wind.

Just my thoughts ,

Jeff

Hey Jeff

Thanks for the suggestion. I did look at the option but I want to use the timber I already have. The weight wasn't really a concern because i am happy to follow the plans, the only reason I mentioned weight was because WRC is so much lighter.

The plan calls for 1 solid piece to shape the mast but I had trouble getting a decent bit of lumber, so I decided to laminate which should by rights be stronger than a solid piece anyway.

Try Lindsay Meyers Timber , clontarf.

He has clear HOOP PINE especially for boat builders, laminating the mast rather than making it from 1 single piece of timber, will create a much stronger and structurally stable mast.

You will need bulk clamps and a long flat bench, but laminating will be stronger,
.

Jeff

WRC isn't up to it, it's light enough, for sure, but it is brittle and has a tendency to crack under repeated bending loads, so I'd not put it in a mast. It's unlikely to survive long-term.

Hoop should be fine un-glassed, especially between layers, but if you want extra strength then glass the outside. In between layers it really won't add much.