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Re: Strip: Stems, gunnels, thwarts
By:Paul G. Jacobson
Date: 7/11/2010, 12:13 am
In Response To: Strip: Stems, gunnels, thwarts (Toby)

: What do you guys use for stems, gunnels, and thwarts? I know ash is
: a common material but are there any others?

Any other wood you have handy is a viable substitute. A very soft wood, such as balsa, is going to be pretty beat up if you use it for stems. But if you cover it with a few layers of glass cloth it gets a lot tougher. Most people prefer a tougher wood like oak, maple, or ash. On big boats the stems are steam bent into shape, so a wood which bends easily is desired. Ash fills the bill here. On smaller boats where the stems are cut to shape you can make them from almost anything.

With gunwales you want to size the parts to match the strength of the design. If the design calls for parts made from 1/2 inch ash and you have spruce or cedar you might want to use stock that is 5/8 or 3/4 inches. If you can't get stock that thick to bend to suit the curves of the design then you can either try steaming or heating it, or laminate 2 or 3 layers of thinner, more flexible, strips.

Thwarts are often used for tie down or lift points. Again, get the strength you need by picking an ample size, selecting good grain direction, and get clear wood or pieces with small tight knots.

: Also, do you install your outer stems before or after
: fiberglassing?

Depends. If you plan to use these as easily-replaceable bumpers then either glass them separately and bolt them on the glassed boat with bronze or stainless steel bolts--or bolt then on without glassing them. When they are all dented and abused, replace them.

On the other hand, if these are going to be integral parts of the boat then treat them that way. Install them and then cover the whole boat--including the stems--with your glass.

If the reason you are asking about using other woods is because it is difficult to get ash near you, consider unusual sources.

Think of raiding a stack of firewood for nearly free hardwood pieces for stems. A 4' branch can be worked down to 1 or 2 thwarts.

I just got the local tree trimmer to deliver a truckload of wood from a tree he had removed from a neighbor's yard. Nice chunks of black walnut about 18 inches long. Great for firewood, of course, or I can split off pieces thin enough to trim on a tablesaw and turn into lumber.

He was happy to leave the wood. It saved him a 20 mile trip to the dump, and the dump fee. We gave his assistant $5 for unloading the truck.

If you can find firewood which was cut last year it will have airdried a bit by now.

Hope this helps.

PGJ

Messages In This Thread

Strip: Stems, gunnels, thwarts
Toby -- 7/10/2010, 9:00 pm
Re: Strip: Stems, gunnels, thwarts
Bill Hamm -- 7/11/2010, 2:56 am
Re: Strip: Stems, gunnels, thwarts
Toby -- 7/11/2010, 3:54 pm
Re: Strip: Stems, gunnels, thwarts
Paul G. Jacobson -- 7/12/2010, 3:55 am
Re: Strip: Stems, gunnels, thwarts
Bill Hamm -- 7/12/2010, 12:25 am
Re: Strip: Stems, gunnels, thwarts
Clayton Plunkett -- 7/11/2010, 6:38 pm
Re: Strip: Stems, gunnels, thwarts
Bill Hamm -- 7/11/2010, 12:24 am
Re: Strip: Stems, gunnels, thwarts
Paul G. Jacobson -- 7/11/2010, 12:13 am