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SMcK
05-23-2017, 07:29 AM
Any suggestions on the best way to handle this ~5" split would be much appreciated.
The transom is white oak, solid everywhere else and the split is well above the waterline, so I'm pretty sure there's no need to replace the whole transom (?).
The wood surrounding the split is solid.
The damage was apparently caused by vibration from the motor mount(?); the six mounting holes can be seen just above the damage. I'm not planning on putting a motor back on.
There is one plank (cedar) that ends on the split area that I know I have to resecure after repairing the split.

Thanks very much for any suggestions/advice.

(Hopefully these links work):
http://i36.photobucket.com/albums/e23/SMck/WP_20170521_09_26_12_Pro292_zpslkojwhr8.jpg?149554 1840212&1495541840886
http://i36.photobucket.com/albums/e23/SMck/WP_20170521_09_25_12_Pro291_zps8pn7r3m3.jpg?149554 1840213&1495541840887

nedL
05-23-2017, 08:05 AM
One difficulty with wide spans of white oak (like a transom) is that oak is dimensionally very unstable across the grain and expands and contracts significantly. The difficulty that this presents is that if a tight solid repair is made when the wood is dry, then as it gets wet and swells up there is no place for the wood to go, which may force other things to happen, and then as the transom dries out again next winter the repair may tear itself apart and cause the split to open up and grow longer in length.
I think if it were me I would clean up both sides of that open “V” shape of the spit to good clean wood, then do what I can to put moisture back in the wood now to get it to swell up and close up as much as possible (wet towels inside and out of the transom for a week or so). Then I would cut a matching “V” shaped dutchman filler piece and glue it in on one edge only. Doing this will minimize stressing things too much when she goes back in the water, and next winter when things dry out again it will be able to move (possibly open up) as it wants to without tearing things apart again.

Peerie Maa
05-23-2017, 08:16 AM
In addition to nedl's advice I would fit a fashion piece, covering at least two planks above and below the split.
Like these, but faying the plank, so that the plank can be fastened to them.
http://industrialbritain.co.uk/forumstuff/forecabin/tr8.jpg

Tom Robb
05-24-2017, 03:40 PM
That looks more like a chunk missing than a split.
Probably irrelevant at this point, but I can't help wondering about (1) what sort of motor needed 6 mounting bolts and (2) why would you'd want a motor on that little cat?
But the fashion piece thing Nick mentioned looks like a good idea and then replacing the entire white oak transom with something more suitable.

adampet
05-24-2017, 06:17 PM
http://i36.photobucket.com/albums/e23/SMck/WP_20170521_09_26_12_Pro292_zpslkojwhr8.jpg

http://i36.photobucket.com/albums/e23/SMck/WP_20170521_09_25_12_Pro291_zps8pn7r3m3.jpg

Perhaps a dutchman?

wizbang 13
05-25-2017, 02:42 AM
I'd run 5 or 6 saw kerfs through the whole transom and fill them with epoxy. Essentially turning one wide plank into 6 narrow ones.

catboatsteve
05-25-2017, 10:03 AM
Hi, First attempt to ascertain if the split is on the seam. Beetle transoms are made up of 2 or 3 boards with tong and groove joints. At the pictured place in the transom there's a lot of movement due to water and inevitably they split(to much expansion& contraction for the grain strength) , plus the oak wasn't always as dry as could be. If it's on a seam trowel epoxy as a quick fix or cut a Dutchman set in epoxy. When you're all done with the restoration just keep the area painted well.

SMcK
05-26-2017, 06:21 AM
Thanks very much for everyone's input. It sounds like dutchman/epoxy is the way I'll proceed. I was initially thinking epoxy filler only but the dutchman makes me more comfortable with end result. Based on how it comes out, I'll decide whether to add the internal faying piece to secure the plank at the split. I'll re-post pictures when done. Thanks again.