[Rhodes22-list] Swing keel help

[Graham Stewart]

Hi Lou:

I have just re-read your great description of the repairs that you made to
the centerboard housing sides. I have a suggestion for others who might be
tempted such a repair as well as a question for you.

The suggestion:

As your description implies, measurement of the slot is a devilish difficult
problem to solve so I thought I would share how I eventually addressed this
problem. As you know, the slot is not just a symmetrical rectangular hole.
It is tapered along its length and height and this makes it difficult to
measure. Also, just measuring the width of the hole doesn't necessarily tell
you which side of the hole the problem is on. Measuring from the centerline
was a challenge I could not overcome. Also, lugging the board in and out of
the boat repeatedly and lifting it into the slot to check for points of
friction was exhausting - especially for an old guy like me. 

As it turned out the solution to both problems was to make from a strip of
plywood a piece that has the shape and dimensions of the midsection and
widest part of the centerboard along its length. I put a cross pin at the
pivot point so the piece could be lowered and raised with a string like the
centerboard. By making this template in my shop I could be sure the sides
were symmetrical around the centreline and thereby tell, when placed in the
slot,  which side of the hole had insufficient clearance. That at least gave
me a good idea of where the trouble spots were which I could then check with
the actual centreboard. If anyone would like a picture of my template just
let me know. To measure the thickness of the centerboard at its thickest
point I made extended calipers very similarly those shown in Lou's
description. I thought I was brilliant at the time but now realized that the
idea came from Lou. So much for genius.

The question:

I am wondering why you went the route of using G20 panels as patches -
whatever G20 is. Why did you not gradually fill the voids in the sides with
layers of thickened epoxy ultimately covered by a few layers of cloth?
Fitting patches for such an inaccessible space seems daunting to say the
least and I worry about any unfilled gaps that might be hidden between the
patch and the concrete. 

One other point, when I was examining my keel I came to realize that there
were substantial voids within the keel itself. The voids were not at the
surface but extended right into the core. I have no idea whether they were
there from the start of reflected erosion through the cracks in the bottom
of the keel mentioned above. I drilled multiple holes through the outside of
the keel and down into the keel through the cabin sole. I then injected
almost three GALLONS of 


I don't know if I need to go the full route that you followed - I hope not -
but I seem to have some of the same symptoms. I had had no trouble removing
the board in the first place making me think that the sidewalls were still
in place. I had large cracks at the very bottom of the hole where the sides
of the cavity and the bottom of the keel join. The boat had been on shore
for about 4 years when I understood to dig out and then fill the cracks with
epoxy and cover the area in several layers of cloth. I "thought" the
clearances were sufficient by making what were crude and totally inadequate
measurements. When I reinstalled the board the gap was insufficient. As the
comment above makes clear, measuring is far more complicated that one might
think at first.

I have ground out the marrow places primarily by using a 1 1/2" rotary
sanding drum on the end of a 2' bit extender and powered by my electric
hammer drill. I now need to again repair that area without simply making the
gap too small again. I do NOT want to have to do this a third time. That
might be the straw that.....


Graham Stewart
Agile. R22, 1976
Kingston Ontario Canada





-----Original Message-----
From: Rhodes22-list [mailto:rhodes22-list-bounces at rhodes22.org] On Behalf Of
Lou Rosenberg
Sent: April 19, 2016 11:03 AM
To: rhodes22-list at rhodes22.org
Subject: Re: [Rhodes22-list] Swing keel help

I just want to chime in w my info on my 81 c/b restoration job.
I posted the entire job on the Rhodes22 OWNERS site.  Its readable as a pdf
file w illustrations.  Roger Pihlaja helped me write the text especially the
parts about the chemistry of cement and how it can impede the board travel
if the trunk swells like mine did.  

http://www.rhodes22.org/rhodes/r22boardtrunk.pdf

I would second all the remarks about getting the boat on stands.  No serious
repairs can be made to the trunk, CB when on the trailer.

feel free to ask questions no matter how mundane they may seem.  This is a
tough job. IT took me a full year to restore mine but its been worth it! 

My 81 sails upwind nicely w the board 3/4 down!
Lou
sv Miracles
on the hard in Mill Basin, Brooklyn



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