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Re: Strip: External Stems
By:Bill Hamm
Date: 2/18/2009, 1:44 am
In Response To: Strip: External Stems (mtkayak)

: I have a couple questions about external stems.

: I think I have done a pretty good job of fingering all the strips together at
: the bow and stern. I probably spent more time there than I needed. As I
: read from Nick's book he says to saw and plane off the ends until you get
: about 3/8" to 1/2" wide flat area to which you place the stem
: lamination. What I don't quite understand is that at 1/2" the two
: sides are now separated with no glue joint. Wasn't that the purpose of
: gluing the finger joints together in the first place? At 3/8" a bit
: of the joint is left, but not much. Is the stem more a function of
: covering up sloppy finger joints or is it truly a matter of adding
: strength and durability? Since I did such a fine job with the joints can I
: just plane down to a 1/4" flat and have a thinner stem? Granted that
: would be quite a small stem. How far back onto the hull do you typically
: carry the stem? If it gets sanded flush to the hull it gets thin quick.
: And how tight of a stem radius is acceptable on the very bow and stern?
: Fiberglass doesn't like to go around sharp corners. Is it acceptable to
: sand quite pointy and run the glass off the end and not wrap it?

: Sorry for so many questions. They seem to come in flurries.
: Thanks

There are several ways of making the ends of the yak. But you don't do them all at the same time. If you want an external stem you have to cut back the strips to have room for the external stem to be attached. You can also just fit the strips from both sides together without using an external stem. And there are a couple ways of doing that (it's in the book).

You're correct that fiberglass won't make sharp corners easily, the longer it's wet though the easier it is to bend and will make tighter corners if cut on a bias (fibers at 45 degrees to the stem's direction). If you don't wrap the glass over the ends it'll leak, there's not enough bonding area for the two sides to attach themselves too doing it that way. Would also be very damage prone.

Bill H.

Messages In This Thread

Strip: External Stems
mtkayak -- 2/17/2009, 2:03 pm
Re: Strip: External Stems *LINK* *Pic*
Charles Leach -- 2/18/2009, 2:27 pm
Re: Strip: External Stems
Bill Hamm -- 2/19/2009, 7:47 pm
Re: Strip: External Stems - Glassed *NM* *LINK* *Pic*
Charles Leach -- 2/18/2009, 2:32 pm
Re: Strip: External Stems
Bill Hamm -- 2/18/2009, 1:44 am