Re: Keel Stabilization OLSON 911

From: Greg Hyland <gregh414_at_hotmail.com>
Date: Fri 04 Apr 2008 - 08:55:30 PDT
To: <TBRIELMANN@aol.com>, "Derek Reijnen" <Derek@reijnenco.com>, <olson911@SailPix.com> 





Tom and Derek-



I'll address my comments to both of you since it seems that you both have the problem I addressed and corrected with "Alyse", my 1986 Olson 911SE.  



In my opinion, the design of the Olson is weak in the area of the attachment of the keel.  There is a great amount of stress on a very narrow attachment point when the boat is on the tilt.  The keel bolt attachment through the hull does not adequately distribute the side to side forces.  This results in the crack at the top of the keel that both of you and I have encountered.  



My problem showed up early in my ownership and was probably brought on by my hitting rocks better than a half mile off shore on Lake Michigan north of Milwaukee in 5+ foot seas.  For many years, part of the Spring commissioning involved the ritual of chipping off the cracked and flaking epoxy at the keel top joint and repairing with more epoxy and/or BoatLife caulk.  After about a week in the water, the bilge would fill with an inch or so of water as the lake seeped in around the bolts.  About five years ago, I bit the bullet and went for the permanent repair.



My crew and I performed the work over a weekend and a couple evenings.  It was not a task for the faint of heart but certainly can be done with minimal expertise (as evidenced by our doing it.



Alyse winters on a trailer with three adjustable pads on each side.  This permitted the controlled raising of the boat off of the keel without letting the keel bolts get free of their holes in the hull.  We did not have the capability of repositioning the keel if it had gotten away.  This left a small (about 3" as I recall) but adequate area to access across the top of the keel.



The steps that we followed were:



    
  
  1.   The epoxy at the top of the keel - hull joint was chipped away to minimize the potential damage to the hull when the keel was dropped.

  
  2.   The keel bolts were all loosened, leaving the nuts still attached on the tallest bolts to make sure we didn't raise too high and lose the keel.

  
  3.   The keel was lowered (actually the boat was raised) by increasing the supporting pad heights.

  
  4.   The top of the keel and the bottom of the hull were scraped clean of all the old bedding compound and cracked epoxy.  The bad epoxy areas were repaired.

  
  5.   New compound was added to the top of the keel.  I believe we used 3M's 5200, but 4200 would probably have been the better choice as it maintains more flexibility.  This was allowed to cure for a while then the boat was lowered back down onto the keel.  We waited an additional day before snugging up the bolts so as to not squeeze out all the compound.  Excess caulk was added around each of the bolts inside in the bilge.

  
  6.   The boat was all put back together - the bolts were tightened and the joint faired with new epoxy.






The following year, we addressed the localized stress on the hull by adding stainless steel plates to the inside of the boat.  These plates were 1/4 inch stock, and were about 6 x18 inches.  I feel this is a necessary addition and has had a positive effect on the sailing stiffness of the boat.



Each compartment of the sump was done separately.  While this was done for convenience, I would be concerned for the large amount of heat generated by the quantity of epoxy used if any more were done at once.



    
  
  1.   The nuts were removed from the bolts, the bilge area was cleaned and roughened, and a heavy coating of vaseline placed around each bolt to keep the epoxy away.   

  
  2.   Epoxy with filler (West System) was poured into the bilge to cover the area covered by the plate to form a flat bed for the plate.  When the epoxy had mostly cured, the plate was set into it over the keel bolts.  The plates were pushed down into the epoxy bed.






    3 The bolts were cleaned and the washers and nuts reapplied.



The end results have been successful.  The crack at the keeltop has appeared again, but it is hairline in size compared to the pencil sized that used to be there.  We no longer get any water infiltration from below.



I wish you luck with your attempts.  Feel free to contact me for further information if you need.



Derek-  I would not find it likely that you would need to replace the stainless steel keelbolts.  These were in fine condition on Alyse.  As these are molded into the keel, it is something you'd want to avoid if possible.  I think you'll find the problem to be with the hull.



Greg Hyland






  Hi Greg - I got you emal address from the Olson 911 forum on Sailpix - I own a 1987 California built O911s 'Arabella" that I keep in Rhode Island.  I am contemplating dropping the keel because I see occasional small rust stains on the top of the keel adjacent to points where a couple of keel bolts are.  It may not be cause for concern but I wanted to get your thoughts before I began the project - or avoided it altogether.  I do have a yard considering the work but I can save a great deal of money if I do it myself.  



  The Olson 911s has such a long, heavy keel and it is narrow where it joins the hull.  Even though it has the appearance of being flimsy it seems rather well thought out and strong.  I have not heard of any boats losing the keel or suffering severe damage.  My concern is that the bilge collects some water during the winter months and it freezes.  My boat is a 1987.  Prudence dictates that I eventually take a close inspection but it is costly and time consuming.  I do not suspect water is entering the bilge from the ocean side as it remains perfectly dry unless it rains.  



  Since you have already done the job your suggestions, tips and tricks are invaluable to me.



  Thanks - Tom Brielmann



  tbrielmann@aol.com


  401-348-6664






  Planning your summer road trip? Check out AOL Travel Guides.
  (http://travel.aol.com/travel-guide/united-states?ncid=aoltrv00030000000016) 





    I've just hauled out and discovered trouble with the keel.  As you can see from the pictures, I have a sizeable crack that's developed.  This was a surprise as we haven't hit anything since our last haul out, and there was no sign of trouble at that time. In prior years we have hit submerged rocks twice that required some bondo at the impact location, but with no signs of serious damage.  This last year we grounded on sand once in a race but at very slow speed, but that's about it.



    The yard is suggesting pulling the keel off, replacing the keel bolts and rebedding.  Any advice out there?  







    From: Tom Ringold [mailto:tom@seaviewboatyard.com] 
    Sent: Tuesday, April 01, 2008 12:44 PM
    To: Derek Reijnen


    Subject: Keel pictures




    Derek,



    Sorry for the bad news. Attached you will find a couple of shots of the keel hull joint and the dent in the bottom of the keel. Please let me know how you wish to proceed.



    Regards

     



    Tom Ringold



    Operations Manager



    Seaview West Boatyard



    206-783-6550



    tom@seaviewboatyard.com



    http://www.seaviewboatyard.com

     
Received on Fri Apr  4 08:55:34 2008

























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