Thread: Sea going rowboat design considerations

Picyures of Paul Gartside's Flashboat lifted from Rowing for Pleasure blog





ROWING FOR PLEASURE: Gartside Flashboat in New Zealand

Here the Flashboat is pictured with a St Lawrence River skiff.



This St Lawrence skiff is 21' by only 42" beam. These outriggers help spread the oars

http://www.grapeviewpointboatworks.com/slrs.html







Brian

Originally Posted by keyhavenpotter

While we wait for Daddles......

Clint, the Gartside Flashboat has been a favourite of mine for some time. There was a superb article by Paul in Water Craft of rowing it 2000 miles in the Yukon. Did you see that? Could fax you a copy if you liked. I feel sure people would pay for a professional built Flashboat.

Thanks for the description of rowing the two different types of boat. Helps when you have never seen a Guideboat in the flesh.

Brian

Hi Brian,

Any chance you could email the article to me? I have been wanting to build one of these for a while now and ordered the plans this morning. Paul had said that he had built out of both 3mm "doorskin" and 4mm okoume but the doorskin had to be sheathed.

He also sent me a picture of one clinker built in WRC which looked nice but obviously much heavier.

Any help appreciated in getting a copy of the story.

regards,

AD

Water Craft still have back copies available for the issue the article was in, and it can be ordered over the internet.

No 33, May/June 2002

WATERCRAFT

Brian

Thanks Brian,

I've ordered it from them.

AD

Andrew, If you build this let me know or post on it. I will be looking at building it myself to show not next year but the one after. I am a one man show here!

The Flashboat looks awesome. My interest is in making the lightest one possible. We have 3mm Okoume here...I'd even consider using something exotic like carbon/kevlar to keep it VERY, VERY light. Easy to say, to expensive to do. 3mm Okoume...maybe get away without sheathing? Glass and resin is so heavy....

In the Water Craft article Paul says he built two boats. One 3mm sheathed with 133grm, (0.44oz / sq ft) which came out at 58kg. The second boat in 4mm unsheathed Bruynzeel, cedar stringers came out at 41kg.

Just received a reply from Paul Gartside about 4mm ply usage to build the Flashboat. His recollection is that she uses 4 sheets of 4mm to plank and 1 sheet of 9mm for the frames.

Brian

[QUOTE=Compass Project;1044203]Andrew, If you build this let me know or post on it. I will be looking at building it myself to show not next year but the one after. I am a one man show here!

QUOTE]

Will do Clint. Paul has digitised these plans so they are available electronically now too!

I won't be able to get started for a little while either as things are very busy here but I will keep you informed.

regards,

AD

Re-reading the Water Craft article on the Flashboat has made me realise that the 4mm Bryunzeel ply was unsheathed.

Now, in the UK Timbmet are the importers for Bryunzeel ply and I have a local depot. Last year my son noticed that they had 20 year guaranteed Bryunzeel 4mm gaboon marine ply listed at £19.94 a sheet, everything else was much dearer. We assumed it was a mistake and never checked.

I have been looking closely at what coastal rowing boat to go for. I really like the Brightside design for a number of reasons, but when the plans arrived they basically insist on full sheathing. the materials list calls for 12 litres of epoxy - that's £160 alone. Plus cloth another £160. So £320 to make the boat at least 25kg heavier, and I am wanting to car top this design! Total weight would be too heavy.

I have loved the Flashboat since reading about it 7 years ago. Paul confirms it uses 4 sheets of 4mm. So to make this lovely design will cost me only £80 in hull ply and hugely less in epoxy. Also uses one sheet of 9mm for the frames.

So, I rang the depot. Yes they had stock, but only 9 sheets left and no more since product was discontinued. The price was actually for 50 off pallet but they also honoured that internet listed price.

Went down yesterday to look, lovely. No voids, nice even three veneers, not super thin face and one thick veneer. So bought the 9 sheets of ply and trying to work out explaining it to the wife.

I have to complete a very slow Snipefish build, son has just started his Shearwater, so build is a far bit off yet, but it's a nice feeling to know that sometime in the future, we have the plans and ply to build two boats together.

For now, I will try very hard to catch up on the house and garden over this winter and not feel quite so guilty when we start.

Thanks to this thread I will enjoy a warm glow of expectation while decorating!

Brian

Originally Posted by keyhavenpotter

So, I rang the depot. ... snip ...

Thanks to this thread I will enjoy a warm glow of expectation while decorating!

Brian

Sod

Richard

what's that old saying about right places and time?

Guy's, and I guess mainly PAR,

it's very difficult to get the weight of a ply rowboat low enough to successfully car top. 14.9 at 42" beam is only 2" wider than my Curlew sailing canoe from Solway Dory, so is good size to fit roof racks. It would be good is she were also light enough to lift comfortably,

so gang, what about building 14.9 as a skin on frame, as per the Umiak used on the Shipyard Raid.



History



Tom Yost's kayak building manual could be used as a building methodology?

Wood Frame Kayak Builders Manual - Homebuilt SOF kayaks by Thomas Yost

Brian

Skin boats can be quite light, but they also, like everything else in yacht design offer up their share of compromises. One sharp rock and you've got a problem in a skin boat. Repeated beaching, dragging over sand bars, filling with rain water or dropping bottles of beer (which break) into the boat are all things that commonly occur, but must be avoided with these boats.

I think the shape would work well as a skin job, but some of the advantages of 14.9's design wouldn't be used to full potential. The flat bottom panel would be a problem with this construction method, exposing it to potential penetration. A modest V bottom with runners would probably be a better route to protect the skin.

I haven't done any direct comparisons, as I don't have much use for skin craft, but I suspect you'll not make it much lighter then a well built glued, Okoume, lap strake version.

If she was built with 6 mm bottom and 4 mm topsides, then a delicate boat (better then a skin boat though), but she'd be exceptionally light for her size. I still don't think she's particularly heavy with the 9 mm bottom and 6 mm topsides.

Cartopping is more an issue of loading ease then boat weight. A heavy boat that can be easily loaded on the roof is acceptable. A light boat that is a pain to load isn't.

Brian, have a look at the skin on frame boats on these pages jwboat campcruisingcortez adirondackguideboat At 42 pounds for the 15ft guideboat I think it would be lighter than ply. According to the folks at Greenland Kayaking Forum - Message Index the 12oz ballistic nylon with a 2 part polyurethane coating is much tougher than most people think.

Kelvin

Thanks PAR and Kelvin. The picture of the 13' Guideboat is really encouraging and the weight 31 lbs!. Can just imagine the 14.9 built that way.



In fact I notice the RYD 12.6 is 13'4" LOD so just about perfect for a shoulder carry down the cliff steps and away on the sea. If I promised to be really careful, what do you think PAR?



Could have a flat bottom board the same as the Guideboat above.



The thing is you see, by the time I have caught up with the garden and home decorating, the temperature will have dropped and using epoxy will be really hard going. It would be nice to be able to put a lightweight boat like this together between Year End and the Spring when epoxy ply is just not possible.

Brian

In an earlier post Clint mentioned the Boat Design thread. Went through the whole 36 page thread and came across this fantastic video of a Finnish two man coastal racing skiff. Race up to 60km.

[ame="http://www.youtube.com/watch?v=w8rwUgGHLSY"]YouTube - Pikkulintu HD 720[/ame]

One man version -



Yksikkö suunnittelussa

Brian