Mast bend

[G Kiba]

Tom, The white mast looks to be a fractional rig (forestay some distance from the top and swept back spreaders). It's made to be bendy. Funny, I am dealing with exactly the same issue as I am relatively new to my boat too. I just had a topping lift and foreguy added by Easom Rigging and he noticed that my mast was too vertical in his opinion. That's because I tightened the forestay just like you did. I did this because I would run out of backstay adjustment and the headstay would still be too loose. The standing rigging is 5 years old. Current solution (on his recommendation is... Re-adjust forestay (lengthen) and shorten the backstay. Then sail and adjust so there is a small amount of weather helm. When the boat is at rest, release the backstay so that there is no bend. When sailing, add backstay pressure and amount of bend for conditions (wind, waves,) to remove-reduce mast pumping. One thing he said that sticks with me is "A straight mast can lead to more mast pumping". Which is what my boat is doing. Now this advice is specific to my boat. Things are different for masts the don't bend and more critical for fractional rigs.

 

[goldenstate]

Tom, The white mast looks to be a fractional rig (forestay some distance from the top and swept back spreaders). It's made to be bendy. Funny, I am dealing with exactly the same issue as I am relatively new to my boat too. I just had a topping lift and foreguy added by Easom Rigging and he noticed that my mast was too vertical in his opinion. That's because I tightened the forestay just like you did. I did this because I would run out of backstay adjustment and the headstay would still be too loose. The standing rigging is 5 years old. Current solution (on his recommendation is... Re-adjust forestay (lengthen) and shorten the backstay. Then sail and adjust so there is a small amount of weather helm. When the boat is at rest, release the backstay so that there is no bend. When sailing, add backstay pressure and amount of bend for conditions (wind, waves,) to remove-reduce mast pumping. One thing he said that sticks with me is "A straight mast can lead to more mast pumping". Which is what my boat is doing. Now this advice is specific to my boat. Things are different for masts the don't bend and more critical for fractional rigs.

Sounds good - I concur re: fractional rigs and understand the front/back tension issue with the forestay and backstay.

What are the symptoms of "mast pumping"? Does the mast flex fore and aft when you are sailing?

 

[G Kiba]

Sounds good - I concur re: fractional rigs and understand the front/back tension issue with the forestay and backstay.

What are the symptoms of "mast pumping"? Does the mast flex fore and aft when you are sailing?

Yes. Fore and aft 1-2 inches in 12-15 knots. Movement is in the section between upper and lower spreaders with most of the movement closer to the uppers. Scott told me that you usually lose a mast when it is allowed to invert back on its self. Picture a bow that is released and the recoil sends the bend aft. So keeping the mast bent forward becomes some what important. Reason for running backstay, checkstays, or Staysail stay.

I don't really want the added work of runners and checks, so I intend to keep the mast bent forward with backstay pressure. He advised that I could use my new pole topping lift as a make shift staysail stay (forward attached to the bow), When sailing in difficult conditions, it could buffer the pumping and aid in preventing the curve from inverting on a long tack. I like the idea.

 

[Godzilla]

They do give me minor concern. But I have seen it before too--in old airplanes:

View attachment 36243

Thing is the plane has frames in the fuselage that create the wrinkled appearance.
The mast to my knowledge does not have frames, ribs or stringers.