The "two rabbet" stem?

[HarryH]

My stem rabbeting situation looks a little different than those depicted in the books by Rossel, Steward, Chapelle and others. Or maybe I am missing something fundamental.

The confusion for me seems to originate in that the keel is sided 3", and the stem sided 4" (back to the second station or so). The offsets give the rabbet above baseline from stem to stern, and it seems to fair in nicely on my profile lofting. But it seems like the rabbet is for the 3" keel width all the way to the bow, that is, no apparent transition or such to the 4" sided stem.

On the deck plan I've drawn the planking thickness where the waterlines meet the half siding of the stem to get the rabbet, back rabbet and bearding lines. But the rabbet found this way does not match the rabbet faired on the profile because of the aforementioned difference in width between keel and stem.

Do designers always draw rabbets in profile this way, that is, the keel and stem rabbet line faired continuously even if they are sided differently?

To take advantage of the whole 4" width of the stem, I plan to project the waterlines/stem half siding intersection in plan up to the profile to get my true rabbet cutting line. But I am a little timid to make chips fly until I check with you guys....

Thanks,

HH

[Thad]

Your offsets should give half breadths for the rabbet. It is likely that the extra half inch siding each side would be kept in the bearding for plank landing while the cutwater would fair off the rabbet line. Backbone structures seldom carry the same halfbreadths end to end but they will be faired together in lofting, as they will be in the timbers and planking.

[ken.bryant]

I face what sounds like an identical situation with plans for Maid of Endor: a 3.5-inch keel, a 2.75 inch stem as marked on the construction drawing, a matter so confusing to me at first that I nearly sent this very same posting! But the offsets for the keel make it clear that the two are indeed intended to be faired together.

[HarryH]

Thad, your point is well taken regarding the extra landing for planking. The bearding line will be on the full 4".

I do not have half breadths for the rabbet on the stem. The boat is strip planked, and the first strip is beveled and fastened flush to the side of the 3" keel. Only the stem has an actual cut-out rabbet.

If I used the extra stem width for the rabbet line, would it create an unsightly fairing in the forefoot are where keel meets stem?

Well here's an edit to my own post....I am going to fair to the keel rabbet on the stem as well, enjoy the greater plank land...

Thanks for your replies...

H

[ 12-17-2005, 11:05 AM: Message edited by: HarryH ]

[Chan]

Harry,
Since you're strip planking, have you thought about just laminating a false stem after the planking, avoiding the need for a true rabbet?

[HarryH]

Chan...I have. In fact, the designer made a note to leave off the last outer three laminations, and then work over the bevel, which is a very close approximation of the rabbit. Then glue on the last three and commence with some chisel work....only confusion arose for me when my lofting from his offsets shows leaving off the last FOUR would better suit his suggestion...

SIGH...wish he was still alive.

Thanks,

H

[dcobbett]

Harry H,

Merry Christmas. Sounds like the Pogo is moving ahead. Please post some pictures when you can.
BTW, I've had no luck locating any links to Bate's plans, etc.

[HarryH]

dcobbett...thanks, yep 'tis moving along, albeit slowly. I am however, bent on enjoying the process rather than hurrying to an outcome.

Seems like Fred W. Bates Marine Design was strictly a locally known enterprise there in Damariscotta. He must have quite a few designs in his estate; he mentioned in correspondence that he had longer versions of Pogo (his letterhead from the 70's also shows several dragger profiles) yet every bit of my research has been a dead end. One contact at the Damariscotta Historical Society was familiar with him; said his son was trying to donate or sell his plans to MIT's collection. Several enquiries there; was told no such luck. I have tried tracking the son down, called numbers that may have been his....no reply.

-H