Mast movement

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ghebbns

What a great day!  Winds were in the 20-25 knot range today and we were consistently doing above 7 knots upwind.  Coming back on a broad reach and surfing down the waves we hit 8.1 knots on the GPS.  It was only for a second, but it counts in my book :)

I noticed that the mast was shifting a little at the entry point thru the deck.  Not a lot but definitely some noticeable movement.  I have a rubber collar on it but it obviously has a little give.  I have never owned a keel stepped boat before so I do not know if this is normal or acceptable.  Any thoughts or suggestions?

Thanks,

Greg
1990 C34 #1040
M 25XP

Fred Koehlmann

Perhaps a silly question from my part, but since you mention never having a keel stepped boat... is the mast "blocked" at the through deck opening? If not, it should be adequately blocked so that it is centered side to side and fore/aft to be as vertical as possible at this point of the mast. There should be no movement at the deck level. As far as I know.
Frederick Koehlmann: Dolphina - C425 #3, Midland, ON
PO: C34 #1602, M35BC engine

kwaltersmi

I don't know if mast movement at the deck is normal or not, but I haven't noticed any movement with our mast in the 4-5 sails we've had since our purchase.  However, there are some wooden shims between the mast and cabin top that are noticeable when looking up at the mast/deck joint from in the cabin.  Maybe these were installed by a previous owner to stop movement (or get better alignment or both).
'87 C34 TR/WK M25XPB
SailFarLiveFree

Dave Spencer

Greg,
The collar that you see is the Mast Boot.  It keeps the rain out (most of it anyway) but has no structural function.  There shouldn't be noticeable movement at the deck collar.  (aka "the partners")  Unless you are talking about a rubber like substance that is solid in between the collar on the boat and the mast.  If so you have Spartite - but I doubt it.  You'll need to make up some hardwood wedges to place fore and aft and side to side to hold the mast in place as it transitions through the deck.  It' not to hard but I'm still struggling to get the right wedge combination for our boat after a couple of years!
Good luck.

DDS
Dave Spencer
C34 #1279  "Good Idea"
Mk 1.5, Std Rig, Wing Keel, M35A Engine
Boat - Midland, Ontario (formerly Lion's Head)
People - London, Ontario

Clay Greene

I agree about there not being any movement at the partners, the through-deck hole. 

After several years of frustration with the mast wedges, I finally went the Spartite route and was glad I did.  No more worries about wedges falling out and it was more watertight.  It still required a bead of sealant but once that was done there was no leaking.  Installation was not all that difficult.  We were worried about it coming out the first time when the mast was unstepped but fortunately we put enough Vaseline around the partners that the mast was not permanently attached to the boat. 
1989, Hull #873, "Serendipity," M25XP, Milwaukee, Wisconsin

Ron Hill

#5
Greg : A number of years back I had to remove the mast and did some rewiring and installed a TV antenna.  The wedges were also popping out so here's what I did :

I took out one of the 4 wedges and made 6 more slightly larger out of oak. After the mast was in place I reinstalled the 6 wedges and "helped them in place" with taps of a hammer.
Slid the boot back down, caulked all around and have never had a problem!!  :D

A thought
Ron, Apache #788

ghebbns

Thanks all for the comments.  I am not sure if what I have is spartite, but it is a hard rubber substance that goes between the mast and the boat.  It was cut on one end so that it could be wrapped around the mast (rather than having to shimmy it up from the bottom.  I noticed when I put it in that it doesn't quite come together at the split.  My guess is that this gap is producing the slack that allows the movement.  I will try and wedge something in to make it tighter.

Greg
1990 C34 #1040
M 25XP

Dave Spencer

Greg,
From the sounds of things, you have a mast boot.  It is common for them to be split so you don't have to pull the mast and shimmy the boot up from the bottom as you suggested.  A mast boot looks like the first picture.

Spartite is likely to be approximately flush with the deck collar.  It is a very think liquid that is poured between the mast and the deck collar that solidifies and serves to prevent mast movement at the deck.  It is semi permanent and is more commonly used by those who rarely step their masts although, as claygr said, many have great success by coating the deck collar with vaseline to allow the mast to slip out to be stepped.  The second picture shows Spartite.

Dave Spencer
C34 #1279  "Good Idea"
Mk 1.5, Std Rig, Wing Keel, M35A Engine
Boat - Midland, Ontario (formerly Lion's Head)
People - London, Ontario

Clay Greene

As I think you can tell from the photo of the mast boot, it does not get into the space between the mast and the deck opening.  The boot attaches to the mast and then the deck collar.  It sounds as though you have some other material in that deck opening space. I have read about owners using innertube material wrapped around the mast, so maybe it is something similar?  Spartite has no elasticity when it cures so I don't think you would describe it as "rubber."

I would either use the traditional mast wedges with a PVC boot or go the Spartite route.  Either way should eliminate movement at the mast through the deck opening and eliminate water getting into the boat in the space between the mast and the deck opening.  As for water getting into the boat down the inside of the mast, let me know if you ever figure out how to prevent that from happening. 
1989, Hull #873, "Serendipity," M25XP, Milwaukee, Wisconsin

stevewitt1

Ron

QuoteGreg : A number of years back I had to remove the mast and did some rewiring and installed a TV antenna.  The wedges were also popping out so here's what I did :

I took out one of the 4 wedges and made 6 more slightly larger out of oak. After the mast was in place I reinstalled the 6 wedges and "helped them in place" with taps of a hammer.
Slid the boot back down, caulked all around and have never had a problem!!  Very Happy

Time for a couple of "Stupid Steve" questions. 
You mentioned sliding the boot back down after positioning the wedges. When the marina pulled my mast last year (I couldn't get my boat up river to my club) I didn't see the wedges removed.  My attachment ring for my boom vang on the mast is riveted to the mast and just above the top of the mast boot.  I can't slide the boot up to put wedges in from the top so I had to tap them up from the bottom. Yes, it was a battle all year keeping them up in there.


My boot turned out to be brittle and cracked but I didn't want to step the mast to put on my new boot from Catalina Direct so I goobered it up with a tube of stuff.  Now I'm going to step the mast, install the new boot next spring but I'm still perplexed about the wedges because my boot can't be slid up the mast to wedge then lower it back down unless I remove the boom vang eye and either try to rivet back or thread the mast and screw it in place. I know the attachment ring on the boom is a "boom vang tang, but what about the mast attachment ring?" Just wondering.

Thanks in advance
Steve

visit us at www.ocontoyachtclub.com and www.warbirdsix.com

patrice

Hi Steve,

If you have to install them from inside, ending up, upside down.
Once you have them inserted, why you don't  just wrap a rubber band 1/4 thick x 1'' wide around the mast under the shim that would prevent them from sliding down, and put a collar on top of the rubber to hold this one on the mast.

Just an idea.

_____________
Patrice
1989 MKI #970
TR, WK, M25XP
   _/)  Free Spirit
~~~~~~

Clay Greene

Not a stupid question at all.  We had the same problem - the mast boot would not slide up because of the vang fitting.  One alternative would be to cut the mast boot in half so it can be taken off and replaced - the problem there is that it will not be as watertight.  But that would allow you to tap the wedges in from the top, which I think is the only way to keep them in place.  This annoyance is the reason we ultimately went with Spartite. 
1989, Hull #873, "Serendipity," M25XP, Milwaukee, Wisconsin

Ron Hill

Steve : If you are going to remove the mast next spring, here is what I did:

My boom vang foot plate is threaded and then bolted in place.  So I removed the vang, the foot plate and boom.  Then unscrewed the 2 bolts for the eye for the bottom main sheet block and slid it up the mast and taped it in place.  The mast boot can then be slid up after the "hose clamp" is removed.  (I have always had a Sunbrella cover [Mainsheet tech article early 1990s] to keep my mast boot out of the hot sun).  Don't forget that you have to unbolt an identical eye in the mast track, for the deck hold down inside.  And also don't forget that that hold down eye has to slide down the mast to remove the mast!! (also remember that that hold down eye must be threaded into the base on the track  on the nast as the mast is slowly lowered back into the boast !!)

Clear as mud?  Hope this helps. 
Ron, Apache #788

stevewitt1

Wow Ron, now I really feel stupid.  I think I followed all you said but the eye on the aft-bottom of my mast that my vang connects to I do believe is riveted, not screwed or bolted, in place.  Not sure about the main sheet blocks you speak of.  I'll check tonight when I get back over to the boat.  I really prefer not to cut my new boot as it's made of LDPE and quite rigid.  I'll try to find the sunbrella article to see how to make a cover as I have a walking foot sewing machine and binding feeder.

Maybe I'll take a pic.

Thanks for all
Steve

Phil Spicer

  Steve: Drill out the rivets then drill & tap the holes for a fine thread machine screw. That will let you move the eye any time you want. My mast comes down every year so I have worked those screws alot.
No problems, and mine never had rivets...Easy fix !
Phil & Marsha,Sandusky Sailing Club. Steamboat is #789,tall/wing-Unv M25XP/Hurth ZF 50 trans.