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Mast Partners and Wedges

terry_thatcher

Terence Thatcher
I recently re-stepped my mast, after struggling to unstep it several months ago. The problem then was mast base corrosion and perhaps SparTite adhesion. As I look at the mast partners again, I see the SparTite problem. The partners have an aluminum cap. That creates a channel, sort of an indentation, that the SparTite fills, which then means it cannot easily slip up out of the partners. Before I restepped the mast, I should have filled that with polisulfide caulking, but I did not think of it in time. I don't think I can get in there now, with the mast in, to fill that void. Anyway, here is my question: I think I need to go back to wood wedges for the mast. Before I proceed, I wanted to know what others do to support and center the mast at the partners. If you use wood or rubber or plastic wedges, what kind of material (or species of wood) do you use. Thanks.
 
I recently re-stepped my mast, after struggling to unstep it several months ago. The problem then was mast base corrosion and perhaps SparTite adhesion. As I look at the mast partners again, I see the SparTite problem. The partners have an aluminum cap. That creates a channel, sort of an indentation, that the SparTite fills, which then means it cannot easily slip up out of the partners. Before I restepped the mast, I should have filled that with polisulfide caulking, but I did not think of it in time. I don't think I can get in there now, with the mast in, to fill that void. Anyway, here is my question: I think I need to go back to wood wedges for the mast. Before I proceed, I wanted to know what others do to support and center the mast at the partners. If you use wood or rubber or plastic wedges, what kind of material (or species of wood) do you use. Thanks.

I just installed spartite on my 382. I used the clay that came with the kit to fill any voids around the collar and partners that would prevent the spartite and mast from being unstepped in the future. Then put Vaseline on everything except the mast so hopefully the spartite will only adhere permanently to the mast. I got a good tip on the Morgan's cloud website in the rig tuning series to join 3 large hose clamps and tighten them around the mast just on top of the spartite to prevent it ever sliding up the mast while sailing. Then I put the mast boot and cover on and it hides it all. We'll see if it works next time unstep the mast... I definitely like the spartite kit so far.
 
I loosened the shrouds a bit and ran a line to the mast to a turning block then the main winch. It didn't take so that much tension. I had to pull it starboard, port and forward one side at a time to make room all around. then filled with the provided clay, got it smooth then put on Vaseline one side at a time. Helps to have a partner with small hands or a rag and screwdriver but I think I eliminated any snag points.
 
I make wedges out of softwood like cedar or pine, tapered cedar shingles can also work. Then I use 6 inch white shrink-wrap tape to cover the wedges and seal to the mast. Easy, cheap and effective and lasts all season.
 
Terry: known you a long time on this site. I think your mast was in the boat for a long time. I still have the original gromets supplied by Morgan on my mast, it is removed annually. The spar tite product I used in the boat I kept in the Caribbean for 14 years Is another story. The mast removal almost lifted the boat, had to be pulled On a number of times To get it to release. The rubber grommet with the upper collar that Morgan supplied is excellent in my opinion. However I don’t think it can be duplicated. I would go with the softer wood partners, tapered accurately with a flange on the upper edge if possible. And I would pay regular attention to them, as the mast deck arrangement in the Morgan does move.
 
Do any of you have pictures of your work? I have not addressed this area at all, and other than some sealant to keep it from leaking, I'm not sure what if anything is even there. When my mast was briefly unstepped (and re-stepped later that same day) in preparation for the pacific cup, the mast lifted out easily and dropped back in easily. All I did was remove and reinstall the mast boot and cover. And later when it leaked I added some 3M4000. There is an aluminum plate bolted to the deck around the mast, but I have no idea what is under it.

I wonder if it needs more support. (though it has survived extensive offshore abuse) When I am at anchor, if I get a light breeze (about 5 kts) on the beam my mast pumps. No amount of rig tuning will fix it. I have attributed it to my tides marine track disturbing the airflow when the wind is on the beam, but maybe the mast partner is a factor as well.
 
I bought a Spartite kit a few months ago and was waiting for it to get sustained warm (and dry) enough to install.
I think I'll start that this weekend. I'll take photos and post what it looks like taken apart. I dug thru my Ted Brewer drawings and didn't see any details on that area. Having never stepped her mast or removed the boot, that's the one of the last areas of her that is still a mystery to me. ;)
 
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Do any of you have pictures of your work? I have not addressed this area at all, and other than some sealant to keep it from leaking, I'm not sure what if anything is even there. When my mast was briefly unstepped (and re-stepped later that same day) in preparation for the pacific cup, the mast lifted out easily and dropped back in easily. All I did was remove and reinstall the mast boot and cover. And later when it leaked I added some 3M4000. There is an aluminum plate bolted to the deck around the mast, but I have no idea what is under it.

I wonder if it needs more support. (though it has survived extensive offshore abuse) When I am at anchor, if I get a light breeze (about 5 kts) on the beam my mast pumps. No amount of rig tuning will fix it. I have attributed it to my tides marine track disturbing the airflow when the wind is on the beam, but maybe the mast partner is a factor as well.

Warren, try wraping/spiraling a halyard around the mast. That sometimes will stop the pumping. It disrupts the air flow or something like that.
 
Warren, try wraping/spiraling a halyard around the mast. That sometimes will stop the pumping. It disrupts the air flow or something like that.

I did try that, and aside from needing to go up the mast to at least the spreaders, it didn't work :(
As a work around, I rigged a dyneema baby stay from the spreaders to a pad eye just forward the anchor locker. It seams to resolve or greatly reduce the issue while moored (and makes it easier to sleep), and is simple to stow when I sail.
 
Warren - for the first 6 years we had Zia, she did the mast pumping you describe. Usually when sailing in light air, but even sitting at the dock. Then a couple of years ago I had a very good rig tuner tune her rigging. I'm not sure exactly what all he tuned, but it hasn't happened since. One thing he fixed is her spreaders were drooping and he got them pointed slightly up again. Don't know if that was a factor - he also adjusted lots of turnbuckles, etc. I wish I would have had the time to get a description of what he did. I installed a Tides Strong Track a couple of years ago so I doubt if that is the culprit.
 
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We battled the pumping rig for a long time. Dana also has the Tides Strong Track and that is not an issue. A rigger made a simple suggestion and it seems to be working. He said to put more tension on the forward lower shrouds to pull the middle of the rig forward. I have been tuning the rig with that in mind for a lot of years now and the pumping is much less evident. Not completely gone, but I'd guess about 90% gone.

Jim
 
RigRite owns Kenyon spars now and sells the mast wedge strips that originally came with the boat. These are a single piece of "rubber" that wraps all of the way around the mast. It's a pretty nice system. But, like everything else from RigRite, they are RIDICULOUSLY expensive and their customer service blows. The price is the reason I used SparTite when it was time to replace. I had great luck with SparTite and have pulled the mast since installing. The mast popped right out. Far easier than getting the original wedge out. I had to destructively dig the original wedge system out of the boat because the mast wouldn't come out otherwise.

Here is the RigRite product: Mast Wedge with Flange: K-77509 The original wedge was white, but I'm 99% certain that this is the same product - different color.

Here is the page specific to the 382 mast section: Kenyon Spars 6092 Mast Section (This page also gives a pretty good indication about how oversized this mast section is for our boats. Check out the size of the other boats this same section was used on.)
 
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Here are some photos of the original wedge system from my boat. It's partially destroyed in the photos. The crane operator was waiting for me to dig it all out because the mast would not come out without removing this wedge.
 

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Thanks everyone for comments. Pulling the mast after it was in for 18 years was a problem. But the real issue was aluminum corrosion at the base, even though I had anodized the mast step. That is partly my own fault for not keeping the drains clear in the mast step and partly Morgan's fault for not having a proper mast step and mast base. See Attainable Adventure Cruising on best mast step designs. My rigger suggests hard wood for wedges, teak or white oak. I never had the original rubber wedge contraption. Mark, be very careful with Spartite. It will work, I believe, only if you fill the space/gap below the aluminum collar as Tyree did--although I might use polysulfide caulking rather than the clay. Otherwise, the Spartite will fill that gap and will not slide out of thbe partners. Alternatively, you don't fill that gap, you will have to remove the aluminum collar to pull the mast. That is not impossible. Mine is screwed in with 8 or so screws. Also, use lots of vaseline, both on the mast and the partners. Again, see suggestions at Attainable Adventure Cruising. I haven't decided which route--Spartite or wedges--to pursue myself. I have a month's worth of work just putting every fitting back on the boat after the paint job.
 
We battled the pumping rig for a long time. Dana also has the Tides Strong Track and that is not an issue. A rigger made a simple suggestion and it seems to be working. He said to put more tension on the forward lower shrouds to pull the middle of the rig forward. I have been tuning the rig with that in mind for a lot of years now and the pumping is much less evident. Not completely gone, but I'd guess about 90% gone.

Jim
More tension on the forwards didn't help. I tensioned them, which caused the uppers to go a bit loose, then I tensioned the uppers then lowers again, and continued that until I wasn't comfortable to how much the hull was flexing. I also had as much mast bend as a high performance racer. It didn't help. So after returning to "normal" tuning with just a bit of bend, I added a removable babystay that I stow while I sail. Maybe the real fix is to add a staysail!

I have lived on my boat full time for more than 2 years now. You might not have it 90% fixed, you just might not be on the boat in the middle of the night once each week when it happens.

I still think the tides track is an issue. It will disturb wind at the after of the mast, while wind is still rushing past the front. That will pull the mast forward. I now also think the mast partner might be an issue as well.
 
Warren

Dana lives on a mooring and/or an anchor and is almost always vaned into the wind. The pumping has been associated with the wind abeam. Since doing the tension on the fwd/lowers it truly has reduced the effect when we do get to be abeam to the wind. On our first 8 month trip down to the Bahamas we had the pumping. On the second 8 month journey we didn't. The only difference was the rig tension. I would like to hear from anyone who has tried this or any other solution and what success they have had.

Jim
 
Does anyone have any pictures of the aluminum collar, partners, or wedges of which Terry speaks? In Ken's photos above, I think I see the aluminum collar, with the pan-head screws going vertically down. I've not seen ours yet and I don't really understand how it's all rigged. I'm going to cut off our disintegrating "boot" this weekend which looks like some kind of rubber tape. Hopefully I can then see the aluminum collar & partners and I'll comprehend.

Also, our mast has not been stepped for 16+ years. Is anyone aware of recommendations for pulling the mast periodically to clean up the aluminum corrosion at the base? I did have standing water there for a while because of plugged drains, which I routinely check now.
 
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More tension on the forwards didn't help. I tensioned them, which caused the uppers to go a bit loose, then I tensioned the uppers then lowers again, and continued that until I wasn't comfortable to how much the hull was flexing. I also had as much mast bend as a high performance racer. It didn't help. So after returning to "normal" tuning with just a bit of bend, I added a removable babystay that I stow while I sail. Maybe the real fix is to add a staysail!

I have lived on my boat full time for more than 2 years now. You might not have it 90% fixed, you just might not be on the boat in the middle of the night once each week when it happens.

I still think the tides track is an issue. It will disturb wind at the after of the mast, while wind is still rushing past the front. That will pull the mast forward. I now also think the mast partner might be an issue as well.

Interesting problem. We've got the Tides Track as well and have been living aboard since 2015. We don't have the pumping problem. Is yours an original mast?
 
Mark, once you get your boot off,it should all be clear--except the gap between the aluminum and glass is down in the hole an inch and a half or so. Also, I think I may have dealt with the corrosion: first, I coated everything with a lot of TefGel, which is amazing stuff. And I will try to remember to clear the drains at he base of the mast.
 
Does anyone have any pictures of the aluminum collar, partners, or wedges of which Terry speaks? In Ken's photos above, I think I see the aluminum collar, with the pan-head screws going vertically down. I've not seen ours yet and I don't really understand how it's all rigged. I'm going to cut off our disintegrating "boot" this weekend which looks like some kind of rubber tape. Hopefully I can then see the aluminum collar & partners and I'll comprehend.

Also, our mast has not been stepped for 16+ years. Is anyone aware of recommendations for pulling the mast periodically to clean up the aluminum corrosion at the base? I did have standing water there for a while because of plugged drains, which I routinely check now.

Mark, while you have your mast down, make sure you give a GOOD inspection to the compression sleeves at both the cap shrouds and the lowers. I found small cracks on 3 out of 4 locations. In addition, make sure to inspect closely the welds at the masthead sheeve box. I found that crack a few weeks before shoving off across the Atlantic. I hired Brion Toss (RIP) to take a look, and his assessment was that this was a serious matter that should be addressed before heading offshore.

*You have to zoom all of the way in to see the crack at the masthead sheeve box. It's in the lower left corner of the sheeve box opening.
 

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I went through my emails to find the quote I received from RigRite back in 2015 for their rubber mast wedge. The wanted $180. No thanks!
 
Do any of you have pictures of your work? I have not addressed this area at all, and other than some sealant to keep it from leaking, I'm not sure what if anything is even there. When my mast was briefly unstepped (and re-stepped later that same day) in preparation for the pacific cup, the mast lifted out easily and dropped back in easily. All I did was remove and reinstall the mast boot and cover. And later when it leaked I added some 3M4000. There is an aluminum plate bolted to the deck around the mast, but I have no idea what is under it.

I wonder if it needs more support. (though it has survived extensive offshore abuse) When I am at anchor, if I get a light breeze (about 5 kts) on the beam my mast pumps. No amount of rig tuning will fix it. I have attributed it to my tides marine track disturbing the airflow when the wind is on the beam, but maybe the mast partner is a factor as well.

Warren - Are you saying that you don't have anything between the mast and the partners? It's just a gap? If it's just a gap, that entirely explains why you have such noticeable mast pumping. You should really have some mast wedges or SparTite filling the gap to provide support to the lower third of the mast. The lower stays not only provide support to the upper "third" of the mast, they also provide a significant amount of rigidity. The mast wedges provide that same rigidity for the lower "third". Masts don't have a lot of strength in compression - they need to be supported. All of that "working" in your mast could really cause problems. Take a look at this article. Or, this one.
 
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Mark, while you have your mast down, make sure you give a GOOD inspection to the compression sleeves at both the cap shrouds and the lowers. I found small cracks on 3 out of 4 locations. In addition, make sure to inspect closely the welds at the masthead sheeve box. I found that crack a few weeks before shoving off across the Atlantic. I hired Brion Toss (RIP) to take a look, and his assessment was that this was a serious matter that should be addressed before heading offshore.

*You have to zoom all of the way in to see the crack at the masthead sheeve box. It's in the lower left corner of the sheeve box opening.
I can probably take pictures if I am inclined to go up the mast, But my sleeves failed on my lowers, and it "tore" an oval shaped slot in the mast. My rigger replaced them with "shroud terminals" which seem to be preferred to the older sleeves. It was fairly easy, but I was planning new shrouds anyway, so it was a small incremental cost to that. I changed my uppers as well.
 
Warren - Are you saying that you don't have anything between the mast and the partners? It's just a gap? If it's just a gap, that entirely explains why you have such noticeable mast pumping. You should really have some mast wedges or SparTite filling the gap to provide support to the lower third of the mast. The lower stays not only provide support to the upper "third" of the mast, they also provide a significant amount of rigidity. The mast wedges provide that same rigidity for the lower "third". Masts don't have a lot of strength in compression - they need to be supported. All of that "working" in your mast could really cause problems. Take a look at this article. Or, this one.
The pictures you posted earlier do look familiar and I remember more now. There was "stuff" in there that looked like your pictures, and was very deteriorated. Whatever it was, it isn't supporting anything. With my memory now jogged, I asked my rigger about it, and it was shrugged off "we probably should have replaced that, but will have to do it next time." The mast dropped in easily, and I just put the boot and cover back on.

Time was an issue. We were using a crane the yacht club uses for launching trailer boats. The tides gave us about an hour, it had to be done at low tide, and we could not leave the mast on the ground overnight. The only intent was to install some lashing at the base of the mast to secure it to the step which was required by racing rules. A pad eye was installed at the base of the mast step, and another on the mast inside the bucket, and the two lashed together. But the mast had to come out to install the pad eyes. Installing all that was only an hours work, but there wasn't an opportunity to do anything else.

Remember, on the west coast hauling out and/or stepping a mast are both rather uncommon. Using the yacht club avoided the high cost and inconvenience of a yard. The riggers shop was at the yacht club, so it was much cheaper, faster and easier.

Anyway, good to know that it might be a simple fix. I also had a lower fail going down the very brutal Mozambique channel, and never got a clear reason why. Now I also have a reason, which makes me feel better. It's something I can fix to prevent from happening again.
 
The pictures you posted earlier do look familiar and I remember more now. There was "stuff" in there that looked like your pictures, and was very deteriorated. Whatever it was, it isn't supporting anything. With my memory now jogged, I asked my rigger about it, and it was shrugged off "we probably should have replaced that, but will have to do it next time." The mast dropped in easily, and I just put the boot and cover back on.

Anyway, good to know that it might be a simple fix. I also had a lower fail going down the very brutal Mozambique channel, and never got a clear reason why. Now I also have a reason, which makes me feel better. It's something I can fix to prevent from happening again.

Brion Toss gives a great example in "The Rigger's Apprentice". I'll paraphrase:

Imagine a dry spaghetti noodle. Put the noodle vertically on a table - one end of the noodle on the table the other beneath your index finger. Press down with your index finger. You'll notice how easily the spaghetti noodle bends. Release pressure. Now, with your other hand, pinch the noodle about 1/3 of the way down from the top. Apply pressure again. You'll notice that the noodle is much more rigid. The lowers and mast wedges provide the same support as you pinching the noodle (that sounds bad, eh? :D). They're providing a lot of rigidity. Tightening the rig places the mast into compression. If you didn't have lowers or wedges, the mast would bend out in an arc. Without wedges, the lower part of the mast is pumping - the result of mast compression with no support (though less pronounced because you have lowers supporting the top third of the mast). That's probably why you broke a lower. Thank goodness that is all that happened!!!

That rigger who told you not to worry about replacing the wedges before heading offshore needs a good talking to! That's malpractice!
 
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More tension on the forwards didn't help. I tensioned them, which caused the uppers to go a bit loose, then I tensioned the uppers then lowers again, and continued that until I wasn't comfortable to how much the hull was flexing. I also had as much mast bend as a high performance racer. It didn't help. So after returning to "normal" tuning with just a bit of bend, I added a removable babystay that I stow while I sail. Maybe the real fix is to add a staysail!

This provides even more support to the argument that your missing mast wedges are the problem. When you tightened the lowers, you compressed the lower part of the mast and the missing wedges caused the mast to bow between the lowers and the heel. What your cap shrouds "felt" was the mast getting shorter - causing them to go slack. You then tightened the cap shrouds, followed by the lowers, followed by... i.e. each time you tightened the rig, the problem was just compounded.
 
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