What Timber to Use for Boatbuilding???

[gregory]

Hi All,
I'm starting to build a ply trailer sailer and would like some info on timber selection. The boat will be put together with Bote-Cote. (I used it on a canoe and a sea kayak a few years back and they're still like new,top stuff).

The trailer sailer keel is and stem is about 300 by 50 by 5metres long. Any ideas about timber type,preferably without spending too much? Also timber for framing/stringers?
Thanks.

[bitingmidge]

Gidday Gregory,

What do the plans say about timber type? That would be a good starting point for discussion.

Can you give us a little more detail on the boat?

Cheers,

P

[gregory]

The plans are for a Pocket Cruiser from Stevenson Projects, the plans use pine to keep costs down. I'd rather something a little longer lasting.

[Wood Butcher]

What's wrong with something like Hoop Pine? If it is sealed properly it'll last as long as the rest of the boat.

[bitingmidge]

Anything will last the life of the boat if it's sealed properly with epoxy, so a reasonably clear pine of any variety should be fine. Hoop would be excellent. Maybe you could get a pine of the treated variety, but test it's gluing capability first.

I wouldn't change the designers specifications too much, I particularly wouldn't use a "more durable" Aussie hardwood, as it will be structurally an overkill by a long, long way, and it will also weigh far too much if you are going to build the boat to it's designed displacement.

If you aren't planning to epoxy coat the boat before painting, then don't waste your time changing from pine either, as it'll decompose at about the same time that the rest of the boat starts falling to bits! :wink:

Cheers,

P
:D:D

[b.o.a.t.]

If you aren't planning to epoxy coat the boat before painting, then don't waste your time changing from pine either, as it'll decompose at about the same time that the rest of the boat starts falling to bits! :wink:

Cheers,

P
:D:D

Given that the keel is generally the first bit of a boat to have the epoxy / glass coating ground off it, I would have thought a rot-resistant timber preferable. Given that treated pine is used to build long-lasting jetties & etc, I felt safe to use it for the keel/skeg of my Teal. The 'poxy membrane has been breached many times in the 7 or 8 years since, always been used in fresh water, yet is still sound and, even more pleasing, attached (glue only, no screws). :U

As for the rest of it, I found that BS1088 "Pacific Maple" A/B marine ply at premium retail from a boat builder worked out about the same $$ as gumby A/C exterior from Bunnings. The BS1088 was at all times stronger, lighter & better made than the "cheap" stuff. The only way to get any plywood 'cheap' is from a wholesaler or fallen off the back of a truck... :dev:

Other timber might be got cheaper from house demolition sites, species depending on where you are. Adelaide is a gold-mine for Oregon in roof frames, & baltic pine in floor-boards (& the demo folks know it). No convenient millable hardwood forests here like in east & west states.

cheers
AJ

[gregory]

Thanks very much for your help. Yes, all the timber will be coated with epoxy.

[spoinky]

Well to get a good keel of the size you are talking about, I would go for Oregan. It can be had in large clear sizes, is quite durable, and not much heavier than pine. It is also structually very strong, but not at overkill level.
Good luck

[PAR]

I pretty familiar with the Stevenson Pocket Cruiser (PC). It's a fixed keel, gaff cat boat, sharing a similar bulbous forefoot that all the little Stevenson cruisers have. It's also the most stable of all the pocket cruisers from them, though it is capsizable, you'll have to work pretty hard at doing so.

Many have been built, with many more currently under construction.

I've listed two discussion forum sites, the first is BYYB (Back Yard Yacht Builders), which is specifically geared around the Stevenson designs. The folks there are builders, most for the first time and happy to share the joys and pain with you. They've been there and can bring you up to speed on what to watch for, etc. This site has no professionals other then myself and one other that stops by every now and then. The Stevenson's aren't active on line.

The second site caters to any design, with specific attention paid to Graham Byrnes work over at B&B Yacht Designs (I believe Graham is a transplant from your country). They also have many of the Stevenson builders there and a much more diverse collection of builders, with a few professionals and a designers tossed in for good measure.

http://byyb.org/phpBB2/index.php

http://www.messing-about.com/forums/

You'll find a kind mixture of folks at both sites, most familiar with your design selection, it's quirks, weak points, strong points and recommended up grades.

I don't mean to chase you away from this site. You'll need these folks too, particular on local availability for lumber, plywood, goo, etc. Finding reasonable substitute wood species can be intimidating, so the guys here can help you out, not to mention tell you where to get good prices on fasteners, etc.

[Wheat]

Having built a 28 footer in timber. I experimented a little. I would look at using Hoop and laminating a capping strip using a denser timber this would improve the strength but keep the weight down and also should she run aground and she will it will give some protection if you penetrate the glass. Also remember epoxy breaks down in sunlight. Also laminating timber to get the desired dimensions can help solve problems like timber movment if you use large sectioned timber.
Goodluck
Wheat:B

[Fair Dink]

Hi Gregory,

I'm not sure if you want a project or want a boat ( I suspect you enjoy building) , but there was a Weekender for sale at the Bribie Regatta a few weeks back.

I don't have details, but someone might.

[Boatmik]

Oregon is fine but can be hard to get now in OZ. We have been finding that the most common replacement species is the plantation grown Hoop Pine.

If you can find some Oregon (Douglas Fir in the USA) in OZ at the right price and quality it is preferable, but if you can't get it hoop pine or meranti will be OK. They are often not so durable, but as you are using epoxy sealing (3 coats can be applied wet on wet with a reputable epoxy brand) then there will be no problem with less durable timber if you are careful with the coating.

Best wishes
Michael Storer

[MikeyRoberts]

Is Hoop Pine the common name for the knots and splits sold as "Dressed Pine" in Bunnings? (I think someone on the forum identified the latin name as "Pinus Crapiata")

[jmk89]

Nope - that's Radiata Pine - hoop is one (significant) step up in quality from radiata

[Tony Hunt]

Hoop pine and radiata pine are very different beasts - different botanically as well as in timber characteristics. Radiata pine is a fast growing non-native (to Australia) conifer (genus Pinus) species, widely grown in plantations, mainly for structural lumber purposes like house framing, although clear grade material is also available and is widely used for cheap furniture etc.

Hoop pine is a native Auraucaria species (related to things like Norfolk Island pine, Huon pine etc). It's slower growing than radiata but is also grown in plantations, mainly in northern NSW and in Qld. Sadly, a lot of the NSW plantations are being replanted with faster-growing but very inferior quality pine species because the shorter rotation (23-30 years for pine vs 50+ years for hoop) gives better economic returns, yet another example of horrible short-term thinking. Hoop, especially the more select grades, is lovely stuff. It's sometimes marketed under the trade name "Arakaria".

[Aberdeen]

.............Adelaide is a gold-mine for Oregon in roof frames, & baltic pine in floor-boards (& the demo folks know it). No convenient millable hardwood forests here like in east & west states.

cheers
AJ

Correct about Adelaide and Oregon.... just rescued some big lumps of Orgeon 150 x 180 that was destined for the rubbish dump :oo: probably been around for nearly 100 years so should be seasoned by now. No idea what it is worth ?? No knots, straight as a die.....

I just have to work out what to do with them :D

[jmk89]

I see in AAPB (latest issue with the article by Mik on the trio of PDRs from Africa) that there is a suggestion that cypress (http://www.timberseek.com.au/html/species-description.asp?TimberSpecies=Cypress%20Macrocarpa) (macrocarpa or monterey, not cypress pine) is a good wood to use for boatbuilding.

Any experiences?

[Boatmik]

Howdy - good contributions guys!!!!

The Cypress lead really is for timbers that are local in Africa. So we have to look for what is locally available here.

At the moment I am leaning toward Hoop as a replacement for Oregon/fir and Paulownia as a substitute for Western Red Cedar.

The Paulownia is a very good substitute for cedar. The Hoop is OK as a substitute for Oregon/Fir - it has some of the straightness instability problems of all force grown timbers and is all fairly wide grained.

But we have to accept the future and also that the plantation grown Hoop is a good thing in principle. The plywood that comes from it is exemplary in quality - even though it comes in those stupid 2400 x 1200 sheets.

With most boats I would say avoid Radiata (Crapiata) completely. But the PDRacer is a special case where people can push towards cheapness if they desire to do so - even to the level of using fingerjointed stuff to hold the ply together in the corners.

DON"T ever use finger jointed pinus for anything that is self supporting (not glued to ply at all) or only glued to plywood on one face - the fingerjoints will break really easily. It can be used for gently curved laminations, but will not work for highly curved ones.

Best wishes
Michael Storer

[jmk89]

Howdy - good contributions guys!!!!

The Cypress lead really is for timbers that are local in Africa. So we have to look for what is locally available here.



I agree, but it is available from this mob (http://www.goldencypress.com.au/)in Victoria

[Boatmik]

Thanks for the Cypress supply!

However, let me expand that a little - the people in Africa were trying to ascertain what local wood would work rather than seeking out a particular species. They mentioned cypress as one of the woods being available in their local suppliers.

Using the same thinking when you look in Australia you look in your local timberyard or places you are not going to find cypress. So my article was not a recommendation for cypress - it was to look at what was local and find something of around the same density as pine or cedar or fir with reasonably straight grain and no significant knots.

So not a particular recommendation for cypress - if you uncle has a couple of cubes stashed away and he is happy to let a few boards go - then it might come into the picture.

Best wishes
Michael

[PAR]

One of the more difficult things about design work is selecting wood species that will be available for the client, who may not necessarily be in the same local as the designer.

I have a book that I use which list the physical properties of all the commonly used domestic and imported lumbers in north America. It's a handy reference, but often doesn't have some of the odder types.

Generally, the best thing you can do is find out what the other builders in you particular area are using. Look for light, medium and heavy planking stock, the same with framing stock also look for workability/machinability, ability to accept glue, rot resistance, propensity for checking, splitting, warpage, etc. Most lumber properties handbooks will list fastener holding ability, density, color, weathering qualities, color ranges and finishing qualities of each species, etc.

When looking for a substitute, I look for similar weight, fastener holding, gluing acceptance, finishing attributes and lastly color as a suggestion for a replacement species. Most species can be cross matched with another from half way around the world, will little to no harm or regret in a substituted application.

[cookiesa]

This is a little off topic although still in the same vein I guess...

Anyway the mention earlier of demolition yards got me thinking to a couple of years ago I was getting a piece of timber and remember seeing a stack of western red cedar that had been stripped from an interior wall (hmmmm reminds me the inlaws have a cedar "feature wall".......) There was a sizeable stack.

Has anyone gone down this path for planking? (I assume you would at least want to rip the varnish (Estapol??) off.. although if oiled guess that could make it useless for use with resin.

[PAR]

RWC (Red Western Cedar) is a fine planking material for small to mid size boats, but tends to be too light for craft over say 30'. It's light weight makes it a choice in strip planked builds, especially small boats, canoes, kayaks, etc.

The use of RWC should be matched against the planking species called for in the original plans. If they have similar qualities or you can scale the molded dimension to suit strength requirements, then go for it with the RWC.

[cookiesa]

Sorry I should have been a bit clearer LOL,

I am looking to build about 18ft but probably in ply...

My thinking was we as builders often think "new" and the oregon comments got me to thinking that perhaps demolition yards could be a good source of "core" type timbers. I guess the thing with the WRC would probably be the health issue's around sanding it, although that would be the case if you were ripping new stock anyway. For the extra work, probably more biased towards smaller builds, it could be a way to go strip planking and help reduce the costs.