B.N. Morris Deck Coaming Placement Dimension

[Paul Scheuer]

Hi. I am re-activating my repair efforts on my Morris after a long period of other stuff. What I'm doing now are small sub projects that I can do with limited shop space.

The boat has been identified as a Morris, but I can't prove that with documentation or name plate.
My current project is the repair of both forward and aft deck coamings that have a small section broken off and lost from the top of each. I think I can post pics. (I'll see). The break in the 1/4 in. mahogany is not exactly horizontal since it followed the grain. (pic 1)

The repair sequence on the fwd coaming has been as follows:
The general plan was to laminate mahogany to replace the missing wood.
I cut a 3/32" rabbet in the forward face to allow for additional glue surface at what is apparently a stress point.
The rabbet was about 3/4" wide. (pics 2 & 3)
I oriented the forward lamination with the grain perpendicular to the joint, using four sections approx. 2-1/2" wide.
The center and aft lamination have the grain oriented horizontally. I used two layers so I wouldn't have to steam.

Where I stand today is that I have the new wood in place with only a rough trimming. (pics 5 & 6) (SEE POST BELOW)
I need to arrive at a final shape for the top edge of the added wood.

The question will be what the original shape of the top edge should be..

The residual bedding material/varnish showing on the removed coaming appears to show that the front surface of the top edge of the coaming was exposed above the deck by 7/32" (9.5 mm) at the "tails". The narrower dimension at the tails extends aft of the tails of the deck (pic 9), and was even with the top of the inwales. (pics 8 & 10). The "as removed" coamings show that the bottom edges were slightly exposed below the inwales and deck-frame knees. (SEE POST BELOW)

The deck battens are just under 7/32".

What I need to know is; does the top edge of the coaming follow the athwartship arc of the deck and how far above the deck batten does it extend. From what remains of the coamings, it appears that the top and bottom edges are not parallel.

I had previously replaced the deck-frame knees, so I don't have the screw holes, except for the two aft-most on both tails, to help me align the pieces. I did keep the removed knees, if I need them.

 

[Paul Scheuer]

More pictures

Pictures added to the above Post.
Pics 7, 8, 9, 10, referenced above

 

[divedog]

Hi Paul,
I hope these pictures help. They are of the coaming of my ca. '13 Morris with 24" decks. You can see the shape and dimensions from the residual stripper. Looks like the top of the coaming was proud of the deck by about 3/8". Also see where the center strip/king plank was (to the left of my thumb). Let me know if you need more pictures or dimensions.

Mike Wootton - Spokane, WA

 

[Paul Scheuer]

Thanks Mike. That'll help. Your pics are pretty much what I planned. I replaced the deck frame knees so I have some options on the elevation of the coaming. I didn't want to do anything abnormal to the original design. I've done some additional shaping from the above pics. I'm now working on the 24 inch aft coaming which has the same issue. The aft break was obviously earlier since the broken coaming was painted. I'll do the final shaping after I get the decks mounted, the coaming rounded, color matched and varnished, (after I get the . . . ).

One pic is where I stopped.
The other is dry fit with the deck pieces and batten in position (with some funky reflection from the gloss varnish)

 

[Paul Scheuer]

So here's the repairs, almost ready for stain and varnish.
My Fuji doesn't seem to get the colors true. The new wood is closer to the pink mahogany of the original.
Pic 1 shows both coamings. There might be some additional trimming once I get a good dry fit. I may need to trim the deck framing that I replaced.
Pic 2 is the inside view of the forward coaming. The bungs you see are to repair the damaged/worn screw holes. Some of it done by me as I used the holes to clamp the pieces to a form as I carved and fitted the new wood. These bungs go to half of the coaming thickness with offset inserts on the other side to maximize the glue surface. I'll probably plug the existing deck frame holes as well to get fresh wood for mounting.
Pic 3 is the inside view of the aft coaming. Similar to fwd with fewer hole repairs.
Pic 4 is the outside view of the forward coaming, most of which will not show when installed.
Pic 5 is the outside view of the aft coaming. I made this one about a 16th thicker for strength in this vulnerable area, giving up some of the "crispness" of the original. The outside lamination (of three) has the grain oriented vertically also for additional strength.

The stain and varnish will be relatively dark to match the color of the battens and be close to what I can see was the original color. The mahogany outwales will be the same (subject of a later project when shop space becomes available).