Pumping mast on the Omega: again

c14_Jim

Sailing on Shelter Bay
We discussed this a few years ago. I have some new views on the subject and are interested in hearing from others. My mast was pumping so bad the other day i thought it was going to break the shrouds. I was out in a fresh breeze and he waves were building. I was under main only. I do think the jib helps keep the mast from pumping, but not much. When the main is near centered and pulled in tight that will stop the pumping, but that isn't possible on a reach. If you want to know if your mast can (will) pump; put up the mast on the trailer and walk forward and physically push the mast forward and backward. The only adjustment I found that helped was getting the shrouds very tight. tightening the forestay did not seem to help. I now believe that the tight shrouds somehow keep the mast from pumping. But I don't understand why tightening the forestay doesn't do the same thing. Maybe because they don't attach at the same point on the mast. I don't know.
Any thoughts.
 
I assume you mean the deck is moving up and down under load. Note my earlier post when I described the mast step collapsing. The pumping could be due to a failure of the support under the mast step. To make sure of the integrity of the support you could cut a hole through the bulkhead just forward of the mast step in the storage locker. After my experience I have installed a 4" deck plate so that I can inspect the support easily.
 
Mine is an Omega, so not the same; The mast step is on the floor and I'm not sure what is under it. It does make some sense that flexing of the step (I sensed just 1/16 inch at most when I put my body wt on it) could cause my pumping. However the pumping I was talking about is the mast moving fore and aft, mostly at the top. If the step does depress then that loosens the shrouds and headstay and would allow it to pivot back and forth when bouncing through waves. And...when I tightened the shrouds that may have compressed it to it's limit and that may be why it pumps less.
Certainly something to think about. Thanks
 

Back
Top