SJ23 Tech Tip A05, (Updated 2003-04-06) Bob Schimmel

Index

SJ23 Trailer Keel Guides for Lateral Weight Distribution.
This is a photo of Panache's keel guides.  They ensure the hull is centered on the trailer so the tires of the single axle (3500 lbs) carry equal load and the hull doesn't rub against a trailer fender.  Equal weight on each tire is crucial for a single axle that is loaded to rated capacity.  The steel guides are bolted on the adjustable keel support bar and are lined with cedar 2x4s to protect the gel coat.  The starboard guide leans over a bit further than the port guide so the keel support bar can be lowered for launching and retrieval.  The (1.5x3)" keel support bar pivots on a 3/4" bolt on the starboard side of the trailer and is adjusted up & down with a 3/4" screw jack on the port side.  You can see the jack screw protruding through the bar on the left side of the picture.  Just barely visible below the keel is a wood support pad.

The keel is 7.25" thick at its widest point.  This spot is located just aft of  the forward end of the large cabin windows.  The gap between the keel guides is 8.5" and the sides are protected with soft cedar with the  corners rounded off, hence no requirement for protective rug as on the bunk boards. 

Dirty wet cedar can be slippery but clean wet cedar is usually sticky.  This is similar to the good traction you can get with clean deck shoes on wet gel coat.  The problem is that the gel coat on the keel tends to "stick" to the clean wet cedar.  This prevents the keel from sliding down along the guide to rest on the bottom of the support bar.  When this happens the hull doesn't center on the trailer.  (i.e.: doesn't rest equally on all support pads) and there is a lot of side loading on the keel for the rest of the winter.  I solved this problem after I took this photo by lining the cedar keel guides with 1/4" thick puck board.  This made the gap slightly narrower now the keel can slide down freely when the boat is retrieved.  Alternatively you could use slipperier hard wood, UHMW, Teflon or nylon.  Remember to round the corners of the sheeting.  No point in solving one trouble and then creating another!  Puck board stands up very well to impact in cold weather.  After all, hockey rink boards are lined with this stuff. 

Also see guide posts in Tech Tip A01. 
 

Return to Tech Tip Index. . . . . . . . . . . . . . . Have a Question?