cats put away on Fire Isle for winter but, question about mast "base" on Dart 18s(i have owned 3) that i probably should address to a British or European site since there are so many Darts there: I noticed a grinding sound coming from base of mast where it rests on support in center of cross bar, unlike my 5.5 nacra and former nacras5.7 &5.2& my friend Joes 570 there is No tefflon ball on DART 18 on top of mast base for mast to pivit on, nor is there a place to insert a silicon chip that at beginning of season i use to place on top of mast base on my prindle 16s(had 4) or hobie 16s(had2) , there is just an aluminum mast base on Dart 18 that mast sits on, Inside bottom of mast is a stainless plate that looks to be in excellent condition; a very close look at top area of mast "base" does show wear and is slightly worn on one side. mast came down this summer, not suppriseing since we have to moor our cats in great south bay, after i raised mast i took my wife sailing heard the grinding noise and mast fell! No one injured, my sailing buddies helped put mast up insisting i was paranoid, i sailed solo for 5 mins heard the grinding returned to shore and took mast down. I have a front cross bar for Dart 18 in Fla only item left from cat that sank in last years hurricane(now hav another Dart18 there) so i could ship up to ny over xmas and insert next spring-if that is the solution, and there are no other suggestions, please comment

The aluminum mast base,(ball), does not ride on the SS plate inside the mast base. There is a stainless steel “pin” inside the ball that makes contact with the plate.
There is no way your mast can come down, unless;
A) one of the shrouds lets go.
B) the forestay lets go, OR
C) your rigging was so loose it allowed the mast base to jump off the mast ball.
If the latter is the case, that would explain the grinding. Things are so loose your mast base is sliding around, & allowing the sides of the ball to rub against the sides of the cup shaped base.
Darts run looser rigging than any other Cat I’ve sailed, but you only need it loose enough to allow the mast to fully rotate during downwind runs.
Remember, part of keeping things tight, is the tramp. As you know, the Dart requires no tools to disassemble, hence there are no through Bolts in the beams. The only thing keeping the boat together is tramp tension, make sure it is tight.
There used to be a very active Dart 18 fleet in London, Ontario. I still quite a few come up for sale. Try these guys. I know Woody is the Canadian Dart Dealer, & can get parts etc. I spoke with him a year ago, I think the contact number is still valid.
http://www.dartcatamaran.ca/index.cfm?page=home

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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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I take special notice to all your input on this site,always erudite. My friends/mates expressed your view when i took down mast and refused to sail until i replaced mast base. (I sailed on my 5.5 but really mostly on frenchmade 20.2trimaran with awesome gennecker-we couldnt catch Tornado but wiped out 570 on 18 knot day). I came to this opinion only after reading anything i could get my hands on from European/brit Dart sites and literature where they described the problem as being a worn mast base and solution =ed replacement. I will be in Fla/Ft Lauderdale Xmas and make close observation of my Dart 18 cat there and of spare front xbar. My friend Joe insists he can insert some form of silicon filler to even out very slightly worn area of mast base. I believe rigging may have been a bit loose, i was using very taut amsteel rope to temporarily replace forestay but had done that before in fla until West Marine fashioned new stainless one and we had just done that for a weekend on a nacra 570, so i dont believe that was the cause. However it came down when there was no wind and violent cross currents from powerboats/ferries at all angles and wave heights

ordered/paid windsport faor stainless rectangle approx 1by 15 inchees with only one hole-item sent aluminum but misplaced it! so weeks for a replacement to arrive. one suggustion was to use a bottlecap! does this really work?

I wouldn’t. A bottle cap is so thin, & so soft, it will wear through in the first few minutes.
Go to any machine shop that deals with SS.
Have them punch a disc, (what I did with my Dart). Buy a cobalt bit, ($5), drill two holes, rivet, raise mast...go sailing, for the next 20 years.
Note,Magen they punch the disc, it will be slightly concave. Install it so the concave side is up, the mast will then self Center.



Edited by Edchris177 on Jun 17, 2021 - 07:16 PM.

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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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