Robin,
It's not the keel breaking on grounding, it,s the back of the keel
box where you need reinforcement.  On the GEM, it's supposed to be a
piece of neoprene to act as a shock absorber.  I would be very
cautious about reducing keel weight, you probably need it for
stability.

Incidentally, how do I open the attachment? (the xls file)
John Button GEM 40 'GAZELLE@
--- In MicroClass@yahoogroups.com, LOUVEL ROBIN <robinlouvel@y...>
wrote:
>
> thanks for the tip. but my keel is not breakable. made from 1.5mm
steel plate aerofoil section 75 mm wide at max cord. i will spead the
load at the top and look to building a lighter keel plate of foam
cored epoxy/grp next year. Unless i get a newer boat
>   regards
>
> Philippe De Troy <microclass@s...> wrote:
>           There should be something hard, like an aluminium plate
or U-profile, on the rear side of the case, to avoid the trailing
edge of the keel exploding the case in case of a hard grounding. 
Better break the keel!
>   
>   For the same reason, the leading edge shoud be WIDE on the top,
to spread the load to the sides.
>   
>   Phil De Troy
>     ----- Original Message -----
>   From: Terry
>   To: MicroClass@yahoogroups.com
>   Sent: Saturday, December 03, 2005 7:10 PM
>   Subject: RE: [MicroClass] slow boat
>  
>
>   Interesting
>   
>   I do not have this Wing Ballast Weight. I do have an extended
Ballast Weight that screws on to the bottom of my keel, but I never
bother putting it on. The guy I bought the boat from also never
bothered adding that as we both feel it is worth more keeping the
boat as light as possible when racing.
>   
>   Also, the "hard wood profile insert" you mention, I have
something similar, however I fit mine in front of the keel instead of
the back. This puts the keel back about an inch and personally I
think this balances the boat better (although I have never tried it
with the insert at the back)
>   
>   Thank you very much for the illustration.
>   
>   Kind regards
>   Terry
>     -----Original Message-----
> From: LOUVEL ROBIN [mailto:robinlouvel@y...]
> Sent: 03 December 2005 17:13
> To: MicroClass@yahoogroups.com
> Subject: RE: [MicroClass] slow boat
>
>
>     I will take photos later when it stops raining but the enclosed
sketches should explain
>
> Terry <terry.home@h...> wrote:   Not sure I understand what you
mean by 40mm nose down and assembly kick
> back. Is there a possibility of perhaps sending some photos so that
we know
> what to look for?
>
> Regards
> Terry
>
> -----Original Message-----
> From: LOUVEL ROBIN [mailto:robinlouvel@y...]
> Sent: 02 December 2005 21:11
> To: MicroClass@yahoogroups.com
> Subject: [MicroClass] slow boat
>
>
> my old micro of unknown parentage was sailing very slowly this
season. with
> a standing wave at the transom about 100mm above the deck level.
>
> Time to investigate suspect keel.
>
> Into cradle, drop keel.
> lo and behold as the keel hits the top of the box the whole
assembly kicks
> back and we have a 40mm nose down on the wing. I have been trying
to sail a
> potential submarine all year.
>
> solution fit new wear strip in back of box and sort out plate at
top of
> keel.
>
> may be we will win some silver next year.
> When did you last insprct your drop keel in the down position?
> Regards.
> Robin
>
>
>
>
>    
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