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Strip: Petrel: External Stems
By:Jim Flowers
Date: 10/31/2009, 11:34 pm

I followed the CLC pattern for the internal stems and wound up with fairly fine ends. I think I read somewhere that external stems are now favored for the Petrel design. Unfortunately, there is no information, pattern or material in the CLC kit and nothing Petrel-specific in Nick's book or posted in the forum regarding size or shape of external stems.

From reading various posts it looks like I should trim the strip ends back to the 1/2" width and then laminate the stems from 3 strips of 3mm ash tapered to a 5mm radius at the outer edge.

Some questions remain, however.

1. I noticed some references to mortising the external stem through to the internal stem. Does this serve some hidden (to me) purpose when the strength comes from the fiberglass, anyway or should I just skip it? Without a mortising bit, I would have to do this with drill and chisel so why not just use a dowel?

2. Is it particularly advantageous to glass the hull before adding the external stems and then glassing them over separately or is it just as acceptable to affix the stems before any glassing?

3. How far back should the stems follow the relatively flat keel? One post suggested about 10", in general, and that looks about right for the Petrel lines. A somewhat heartier external stem for the stern is suggested to provide better tracking but as this is to be used as a play boat, I don't see the need for that.

Still trying to catch up.

Messages In This Thread

Strip: Petrel: External Stems
Jim Flowers -- 10/31/2009, 11:34 pm
Re: Strip: Petrel: External Stems - Laminate?
Jim Flowers -- 11/3/2009, 2:05 am
Re: Strip: Petrel: External Stems - Laminate?
Bill Hamm -- 11/4/2009, 1:53 am
Re: Strip: Petrel: External Stems
Bill Hamm -- 11/1/2009, 12:21 am
Re: Strip: Petrel: External Stems
george jung -- 11/1/2009, 8:49 pm
Re: Strip: Petrel: External Stems
Allan -- 11/1/2009, 12:18 am