Bad knees...transom knees

John Birmingham

John Birmingham

Active member
The garvey needs knee replacement. I pulled the old ones off and have a good pattern, now I need need to get some more made up.
badknee.jpg

Any recommendations where I could have a pair of these made up.

I will be having lunch with my father in law on Thursday then traveling to Cape Cod to see my mother. Could say I am going from PA to MA.

Also working on a splash well...

I came across a posting that indicated there are plans for this boat in an old magazine #34 Small Boat from1984. I would like to get a copy of the article showing the plans for a planked garvey by Russ Adams, Somers Point, NJ

Thanks,

John
 
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Yep, those are toasted. Ran into a similar problem with a dory that I had. Good that you could get most of the old knee out. I would make a replacement out of mahogany or white oak. If you can't get the thickness, you could laminate some pieces of oak to get what you need. Pre-drill the holes and use stainless steel or silicone bronze fasteners. I would seal the holes and edges with Boat Life or something similar. How does the planking look where the knee was touching? Is it soft or spongy at all?

Do you have the tools and material to make up some new knees? What is the thickness of the old one?


Nate
 
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Nate,

The other wood is fine. The wood is nearly 2" thick,
kneewidth.jpg
I do not have the abilty to make it myself.

John
 
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Anybody with a jig saw or bandsaw and the right stock could make these. Additional directions for whomever cuts them: Have them orient the grain from the original fore and aft direction (parallel to the rubrail) to the forty five direction. The least amount of grain run out as possible to reduce the checking that is visible to the right side in the "good wood" portion. A good wood for this would be white oak bedded in 5200 or sikaflex 292. You could do this project it is not that hard and the worst would be that some of your fire wood would look funny. Good luck
Frank Middleton
Middletonboatworks.net
 
Is it advisable or feasible to laminate the knees from marine plywood?
 
How many are there. Are they all the same angle? Are they just for the transom where it meets the bottom planking?

I have some white oak and a band saw.
 
Carl,

Because of the way the knee is stressed or "loaded", I'd go with solid lumber where all the grain is running the same direction. Most of the load on the knee is in one plane so the grain should also be in one plane. IMHO
 
Go with clear, white oak you can get a piece 1in thick cut two blocks and glue and screw them together. Very easy to do then just trace your pattern and cut them out. iI don't know how close you are to jersey, I'm on the west side if you need a hand with it. Chris
 
John - Forget the solid hardwood, white oak or other. There is too much of the knee cut away. I don't care which direction you run the grain - the knee will fall! Any one of the red lines could be a split rendering the knee useless. How many years did the original plywood knee last? Plywood is much better suited for a knee of this design. In the old days, knees of this design (big cutaways) were sawn from natural grown crooks, many times hakmatack or oak where the grain actually follows the shape of the knee. Unless you can get some of the latter or cut less away from the knee, stick with plywood. Coat the knee liberally with West epoxy before you install it, and that knee will be around when you and I are long gone.
 
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How many years did the original plywood knee last?
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HUH?

Rich,
How did you reach the conclusion that the original is made from plywood. The knee shown in the photos is clearly not plywood.
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John,
my shop is right off 95 in Mystic. Its five min from the highway. I am at dinner till after 5:00 but if you bring the pattern and the timing works we could cut two in about 20 min.

My White Oak is only 1 1\2 but I bet it is enough.
 
Bob,

Sounds good, I made this Thanksgiving trip a while back and the traffic was not bad because everyone was already at dinner. I will send you my contact info.

My guess is that I will get to your area around 6:00 or 7:00.

It would be great if it works out.

John
 
John, By the way, what is the old knee made of?

Dave, Whether it is or is not plywood is not the issue. If the present knee is duplicated it will be stronger in plywood than solid hardwood, oak, or other.
 
I am not sure what the old knee is made of. Looking at it, I think of cedar.

I am taking it to the lumber yard tomorrow to see if they have something to replace it.
 
John, By the way, what is the old knee made of?

Dave, Whether it is or is not plywood is not the issue. If the present knee is duplicated it will be stronger in plywood than solid hardwood, oak, or other.
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The origional one didn't break eventhough it was rotten. You could replace it with something "stronger", but why?
 
If you have access to it Black Locust would be about the perfect wood for that application, strong and durable. Like Tod said it ws rot that got you, not stress. That particular are of the boat probable sees a lot of water and over time it got through the paint and into the knees. White oak is a good choice but nothing compares to black locust for durability. They say if you drop a white oak on the forrest floor it will last 6 year before rot gets it. Black locust will go 60 years. Of course a good coat of epoxy will prevent rot too.

Eric
 
One additional consideration with using White Oak vs Black Locust. White Oak has been known to have compatibility issues with epoxy. Locust does not. WoodenBoat magazine is full of references to that phenomenon.

John Bourbon
 
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