What experiences have people had with removing their masts with a Spartite ring and the re-installing it? Does the material swell at all?
I’m having an argument with a boat yard who cut off my Spartite ring last year when I was having the mast repainted. There was no reason to cut it off and I wasn’t a happy camper. They used a hacksaw blade to cut it, so the cut removed very little material. However, when we went to put it back on, it wouldn’t fit into the partners and we ended up having to sand it down to fit.
When I had to take off the masts of my F44 to ship it to Europe, I had to cut the PU mast wedges with a hacksaw too. They weren’t set with Spartite, but a much harder Shore A 90 PU rubber that would not budge because it was cast without vaseline on the mast or deck opening. If your Spartite was cast in the opening without vaseline, which is the way they advise if you want a watertight seal, I’m not surprised they could not get it out without a saw.
When you put your masts back in again, I advise you to look for PMC-790. It costs about a third of Spartite (it’s unbranded) and it’s much harder, so it will keep your masts in place a lot better. You use it in the exact same way as Spartite. Spartite is Shore A 55-60 and meant for stayed masts. They don’t say it on their website, but if you call them and ask if they guarantee a good positioning and a good watertight seal with an unstayed mast, they admit Spartite is a bit too elastic for that purpose.
My current PU wedges and seals are vaselined against the deck edge. But I’m not sure if the masts will come out easily.
My mast came out without problems as I had Vasolined the partners before installing the Spartite. The problem was that they decided to remove the Spartite ring from the mast when painting it. They only made a single cut, so we were able to slide it onto the mast and re-use the Spartite ring. However, it no longer fit, and I couldn’t tell if it had changed shape due to being cut or it had expanded due to not being compressed while the mast was out of the boat.
Ah okay, that’s a different story. I doubt if lack of compression has caused the problem; the spartite is cast around the mast and not forced in. I think painting the mast and possibly using a fairing compound, changedd the shape and/or diameter of the mast slightly, enough to prevent the ring to fit again.
Spartite ring should not swell at all and should fit back between the mast and collar in the Spring the exact same way it came out. It should stay on the mast for winter storage. We recommend covering it just for protection from the weather.
Now, if the Spartite ring is over 10-15 years old or has be sailed under extreme conditions, the ring may start to fall to pieces. That is age and normal wear and tear. At this point the Spartite pour should be done again (after removing the old ring).
There is no way it can swell because in essence it is a cured piece of plastic. It definitely does not absorb water. It is supposed to be a very tight fit as it poured in place to begin with. The directions tell you to Re-Vaseline the ring prior to stepping the mast.
Geoff, I really think the paint system changed the diameter of the mast. For a rubber ring cast in situ, a circumference change of 1 millimeter may result in problems getting things back together. I guess you have to cast a new ring. If you do that, I advice you to use the much cheaper and harder PMC-790 PU rubber.
I believe that the real issue was that the boatyard cut the ring off when there was no reason to have done so. That’s what allowed it to change shape and caused all of the later problems.
But if your mast still had the same shape and diameter as before the paint job, why would the cut ring not fit? The ring has been cast, so there is no tension in it. It has not been stretched around the mast.
I can’t answer that. I can only tell you what happened. Probably part of the problem was determining the correct orientation of the ring when it was re-installed. There were no marks to indicate the correct rotational angle.
The bottom line is that there was no reason to remove it and it’s caused a lot of problems since then.
Registration marks on the mast, the ring, and the collar would probably have prevented this problem…in any case, it wouldn’t hurt, and likely this thread will benefit “the next guy”.
There was never any reason for the yard to have cut off the ring. They screwed up and removed it for some unknown reason. There were no registration marks because it wasn’t supposed to have been cut off! Any marks would have been painted over anyhow. This was just a screw up from start to finish.
Hi Michel can you give me information where you purchased the pu rubber that you cast around your masts at deck level as I am about to put the mast back into my Tanton 43.
I used PMC-790 two part PU rubber. It’s manufactured in the USA, You can find it if you google PMC-790. I bought in the the Netherlands (where I live) in a supply shop for casting materials. Note there are different durometer variants with different numbers such as PMC-750. I used the hardest variety which is hard but still a bit rubberlike. I don’t want my freestanding spars to wobble around in the deck hole in a soft rubber bedding.
Thank Michel I am now on Goggle and will find someone in U.K.I have had a stainless steel collar made which is 100mm high from deck level this is bolted permanately to the deck with the original deck ring bolts onto this and clamps around the mast.This was made to make a stronger hold onto mast and to be able to withdraw the mast through the permanent collar.This is a design Nick Charman had made for his Tanton 43 and designed by Yves Tanton the designer.
Say hello to Nick Charman from me if you happen to speak to him.
Your high turtleneck collar will be an ideal base to poor the liquid PU-rubber in. Just make sure that it does not run down along the mast. You can download the Spartite instructions to see how to make a seal below deck around the mast. I made a plywood ring in two half-moon parts that I bolted under the deck. On top of the plywood was a layer of plasticine clay to make a seal. On top of the plasticine clay and on the inside of the deck I rubbed a liberal amount of vaseline to ensure the PU-resin would not stick there. I degreased the mast to make sure the rubber would stick there. If you can’t get the PMC-790 in the UK, get it from FormX here in the NL’s. http://tb.smodev.com/tb/uploads/PMC-790_Shore_90A.pdf or in the USA from Smooth-on http://www.smooth-on.com/Urethane-Rubber-an/c6_1117_1150/index.html.
I used spartite 3yrs ago and although using vaseline I can no longer remove masts. Cutting it loose with hacksaw was beyond my patience threshold. One man on deck and another below pulling while the other is pushing a hacksaw blade back and forth. (with head and sholders squeezed into the anchor locker) I think a new owner can deal with that one. Use vaseline liberaly and if you can fined someting better use that. I lifted the front end of my boat out of the water without the mast budging. Thats what I know about spartite. Numbknots
Been there, seen that, done that! This is my 3rd Spartite’ish job. The first one ended as Numbknots’s did. The second one was due to the yard cutting the ring off when they were painting the mast. Now I’m re-doing it to repair that mistake.
I may have forgotten to mention you have to protect PMC-790 from sunlight. It gets brittle over the years if you leave it in the sun. So you need a boot or tape. Good luck, and if it doesn’t hold up the way you expect, you can fully blame me. :mrgreen:
That post reminds me of my “great” find for mast boots. I used a rubber seal for a sewer pipe that they use to connect the old clay/ceramic pipe to the smaller diameter pvc pipe. It even came with stainless hose clamps and they were something like 15 dollars each. Now that was for a f 28 but maybe those companys make larger ones. Gotta get a break sometime. Numbknots
