I agree with you. The three supports on Penniless are level, the oak block sits on them and is level with the floorboards, but about 3/8 inch higher (I do have the teak and holly sole, which some of the earlier boats did not have). When my mast is in its normal position, the base sits in the little aluminum box and is touching all around. I would go for level with the sole, but if you want 8 degrees of rake, you may want to figure out how to get 8 degrees of slope on the block. Maybe by shimming the front of the block a little?
I also have moved the spacers in the aluminum box. When I got the boat 23 years ago, there were two spacers in front of the mast and two behind. I have since added a bit of rake by moving the spacers and now I have all four behind the mast. The boat is more stable but I don’t see 30 knots of wind (ever?). When the rail is close to the water, I reduce sail. As someone said, 20 degrees of heel is about max. Gary #593 From: CnC-List [mailto:[email protected]] On Behalf Of RANDY via CnC-List Sent: Saturday, March 25, 2017 3:12 AM To: cnc-list <[email protected]> Cc: RANDY <[email protected]> Subject: Stus-List Mast Step Pitch & Helm Balance Listers- Seeking your input here. I'm in the middle of the mast step rebuild project a la http://cncphotoalbum.com/doityourself/maststep/maststep.htm. Lots of pictures of the project at https://drive.google.com/open?id=0B-NqAxQ6JxFTSzRLbFo0NDl6U1E. I'll be cutting new supports from laminated GPO-3 slabs Saturday night or Sunday morning. Before installing the new supports, I have to decide on the elevation of the aft support. Of course I took careful elevation measurements from the cabin sole before removing the original supports. But the question is, what was the original shape of the top of the aft support? I believe the middle of Grenadine's aft support, under the mast step block, was compressed down from its original elevation due to a combination of weakness in the support and standing rigging tension (especially backstay). Have a look at the pictures and you can clearly see what I mean, e.g. https://drive.google.com/open?id=0B-NqAxQ6JxFTLXZuXzd1T1pkR28. This compression has the effect of pitching the mast step aft, thereby moving the masthead aft, thereby increasing weather helm (which I've definitely noticed under enough wind and sail - it was strong under full main and #2 genoa in 30 kts, not surprisingly). However I also believe that the original elevation of the aft support may have been carefully tuned for helm balance, prior to compression below the mast step block due to weak wood and standing rigging tension. The reason this elevation question matters so much is because, using trigonometry, I can calculate the distance by which different elevations of the aft support will move the masthead forward or aft, which in turn will affect helm balance. Each quarter inch of aft support elevation difference could move the masthead about three inches I believe. The last picture (https://drive.google.com/open?id=0B-NqAxQ6JxFTU3hRNmZoMUU1MFk) in the Google Drive folder linked above shows the templates from which I'll cut the new supports, traced from the original supports removed from Grenadine's bilge. I hypothesize that the dashed line I drew at the top of the aft support template may have been the aft support's original elevation. I'm halfways tempted to split the difference and cut the new aft support to have that elevation. Of course, I could be full of crap, because I tune the mast rake using the stays after all, which probably influences helm balance more than mast step pitch. And of course I can control the sail selection and sail trim, which probably influence helm balance more than mast step pitch. However, for a given sail selection close-hauled, with neither the backstay nor forestay over-tensioned, the mast step pitch would certainly influence the masthead position and therefore the combined center of effort of the sail plan. What say ye? Does anyone out there know if the top of the original aft mast step support on a 30-1 was flat all the way across, or did it come from the factory with a little elevation drop to tune helm balance? I'll be committing an assumption about that to a GPO-3 slab with my jigsaw in the next day or two. Thanks in advance, Randy Stafford S/V Grenadine C&C 30-1 #7 Ken Caryl, CO
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