Is my mast really bent - and other stupid questions

Paul the Denverite · Post by **Paul the Denverite** » Wed Oct 21, 2009 3:54 am

So the C-22 made it to my house but the previous owner tied the mast to the deck at the pulpit and the stern (turns out it was to hold the main hatch on, but that's another story). A neighbor & I removed the mast, rolled it 180 and he says, "It's bent from tying it down improperly." And, indeed, it is not straight. "Not so fast," a friend from church says - he taught sailing at the Naval Academy. It may be that what appears as a bend when unrigged becomes the aft curve when the spreaders are properly tentioned.
So, fellow C-22ers I crave your thoughts, input, knowledge, cajoling, etc. Thanks in advance

Banshi · Post by **Banshi** » Wed Oct 21, 2009 5:30 am

While you can adjust the rake of the c-22 mast you can't bend it because of the way it is rigged. I am not sure you could bend it even if you added a forestay down low, it is just to beefy for its length. Which makes me wonder how yours got bent but I suppose if it was tied down hard enough and long enough it would eventually give in to the forces of nature. In this case you might try reversing the effect the same way it was created but I tried that once on an old mast I had and did not have any success.

A small amount of bend won't make much difference for day sailing especially if it is toward the stern of the boat when stepped. Small being a inch or two over its full length

EmergencyExit · Post by **EmergencyExit** » Wed Oct 21, 2009 6:49 am

Like Banshi said a "little bend..." - I'd run a taut line from head to step (like a bowstring) and see how much it stood away from the mast and where, etc.

Gus · Post by **Gus** » Wed Oct 21, 2009 11:19 am

Mast bent from forward to back its ok, but from side to side its not good! The original mast in this boats are pretty tick, big boat stuff, so I doubt it bent because of the way its tied up to the boat. I tie mine up the same way and never had a problem.

Gus

Paul the Denverite · Post by **Paul the Denverite** » Wed Oct 21, 2009 11:22 am

When I demasted a 16' cat I took the mast to a metal specialist who straightened it for me. It was over 3 years later I ran into someone who said they were in the shop when he straightened it. I asked how. The answer: They chucked it up in a vice and 6 guys got on the other end and bent it back!!!! I used this knowledge years later when my son bent our mast on a 16' capri (threw the sheet out the car window, ran over it and ripped the mast of the top of my Explorer). So maybe I'm starting ahead by getting the mast already bent on this one! I'm thinking two saw horses a long ways apart and a real heavy friend in the middle!

Alanhod · Post by **Alanhod** » Wed Oct 21, 2009 11:25 am

Paul the Denverite · Post by **Paul the Denverite** » Wed Oct 21, 2009 12:18 pm

I downloaded the owner's manual before I got the boat home. In the rigging set up section it says to eyeball the mast after first rigging and again under sail to make sure it is straight. It then goes on to describe the aft curve and notes that the shroud attachment points on the hull are slightly aft of the step. It is this offset that causes the curve. As to why... under sail the slight curviture allows the pocket of the sail to set in a little more deeply.

Banshi · Post by **Banshi** » Thu Oct 22, 2009 10:52 am

There is no significant curve in mine when stepped. It would be very minor because the lowers are only slightly behind the step and they should only be tight enough to keep the mast straight (side to side) in moderate winds when sailing upwind. In fact the leeward side will almost be loose when sailing up wind while the windward side will be tight. These mast are way to beefy to put any significant bend in them with just the standard rig.

Gus · Post by **Gus** » Thu Oct 22, 2009 3:23 pm

Banshi wrote:There is no significant curve in mine when stepped. It would be very minor because the lowers are only slightly behind the step and they should only be tight enough to keep the mast straight (side to side) in moderate winds when sailing upwind. In fact the leeward side will almost be loose when sailing up wind while the windward side will be tight. These mast are way to beefy to put any significant bend in them with just the standard rig.

The shrouds in my C-22 does the same thing, but I think it is because the deck pulls up a little bit from under the pressure.

Banshi · Post by **Banshi** » Fri Oct 23, 2009 3:56 am

Since you adjust them while they are loaded any give in the hardware is should already be taken up, there is just a huge load difference between the two when sailing. If they actually flap then they are probably to loose and need some adjustment. A difficult job without some experienced help to pilot and adjust while sailing. Add to the mix that you need a fairly steady moderate breeze (with minimal chop) and it can be a chore. I have been just letting a passenger look up the mast while sailing then adjusting them the next time I go out. Hap hazard at best but since I am not doing any racing it will suffice for now.

Paul the Denverite · Post by **Paul the Denverite** » Sun Oct 25, 2009 5:18 pm

I tried the taunt string out yesterday and have 1 5/8" showing between the string and side of the mast with the widest point being right at the spreader location. Then I took it out, tied it on the pulpit and stern rail, threw a tarp over it and am using it to fend off the currently falling snow.

Gus · Post by **Gus** » Sun Oct 25, 2009 5:47 pm

Banshi wrote:Since you adjust them while they are loaded any give in the hardware is should already be taken up, there is just a huge load difference between the two when sailing. If they actually flap then they are probably to loose and need some adjustment. A difficult job without some experienced help to pilot and adjust while sailing. Add to the mix that you need a fairly steady moderate breeze (with minimal chop) and it can be a chore. I have been just letting a passenger look up the mast while sailing then adjusting them the next time I go out. Hap hazard at best but since I am not doing any racing it will suffice for now.

I eyeballed the shrouds with the mast down, but I know there's some pulling in the deck; I found cracks right where the deck meets the hull. I need to cut and lift the skin where the chainplates are, so I glass some plywood to reinforce that area.

Gus

Banshi · Post by **Banshi** » Mon Oct 26, 2009 4:48 am

I would not sweat any side to side bend unless it was extreme, yours sounds like it is usable. The lower shrouds can adjust the side to side bend out it is the forward and back bend that really can't be adjusted as the boat was originally rigged.

Gus,
My deck has a little give to it on one side but the "chainplate" should be transferring that load to the bulk head not the deck. I have already decided to use some beefier angle on mine. The old ones no doubt have been stressed over the years and give more than they should.

Gus · Post by **Gus** » Mon Oct 26, 2009 9:42 am

You know where the bulkhead attaches to the liner? That's deformed too (I gotta take a photo to give you an idea) I think my boat's been sailed rough in the past.

Windward · Post by **Windward** » Thu Oct 29, 2009 3:48 am

On the C26, I find the mast is inherently flexible,and the adjustable backstay can indeed bend the mast. Once the head stay and uppers are adjusted, I add enough tension to the forward lowers to initiate about 1/2" - 3/4" of prebend at the spreaders... a slight arc with the convex side forward. I then use the backstay adjuster to max tension, and tighten the aft lowers enough to ensure the bend doesn't exceed about 2". I determine bend using the main halyard pulled tight along the slot. That also reveals any lateral bend, which can be induced by uneven shroud tension.

The C26 mast is also vulnerable to mast pumping in strong, gusty conditions; I add tension to the lowers to deal with that.

I use a Loos gauge to do final tensioning on shrouds, which permits me to get them relatively even and makes my results repeatable.