Forums > Windsurfing General

Mast base

Reply
Created by choco > 9 months ago, 11 Dec 2021
choco
SA, 4175 posts
11 Dec 2021 1:11PM
Thumbs Up

I never thought about why there was a pin in the mast base plate, never too old to learn something new

fb.watch/9POiInJH6A/

AUS 808
WA, 501 posts
11 Dec 2021 11:39AM
Thumbs Up

Select to expand quote
choco said..
I never thought about why there was a pin in the mast base plate, never too old to learn something new

fb.watch/9POiInJH6A/


I believe it's there so the washer doesn't rotate when tightening the base.
It just happens to work as a safety device but you then lose some adjustment.
I used to have a plastic block that dropped in the larger part of the slot which did the same but gave max adjustment & the base could not come out.

Basher
590 posts
12 Dec 2021 4:46AM
Thumbs Up

Select to expand quote
choco said..
I never thought about why there was a pin in the mast base plate, never too old to learn something new

fb.watch/9POiInJH6A/



Hi, yes that's a safety feature for when things have already gone wrong. The lug on the deckplate disc stops the mast foot from sliding out of the track. Not a bad idea.

But it's important to realise that when your deckplate comes undone it's often NOT because you haven't tightened it up enough. It's because your mastbase bearings aren't working properly.

Both bearings, above and below the U/J need to rotate freely, or else the action of tacking and gybing can undo the deckplate.
Some people get a double bolt deckplate to prevent this issue - but that's still a really bad solution because when the bearings don't work, the rotation causes the U/J itself to fail instead, because the tendon or Boje joint is continually twisted.

I'm always shocked how few people understand this basic issue. Even that video, linked to above, does not seem to understand the true problem.

Faff
VIC, 1370 posts
12 Dec 2021 8:54AM
Thumbs Up

Select to expand quote
Basher said..

choco said..
I never thought about why there was a pin in the mast base plate, never too old to learn something new

fb.watch/9POiInJH6A/




Hi, yes that's a safety feature for when things have already gone wrong. The lug on the deckplate disc stops the mast foot from sliding out of the track. Not a bad idea.

But it's important to realise that when your deckplate comes undone it's often NOT because you haven't tightened it up enough. It's because your mastbase bearings aren't working properly.

Both bearings, above and below the U/J need to rotate freely, or else the action of tacking and gybing can undo the deckplate.
Some people get a double bolt deckplate to prevent this issue - but that's still a really bad solution because when the bearings don't work, the rotation causes the U/J itself to fail instead, because the tendon or Boje joint is continually twisted.

I'm always shocked how few people understand this basic issue. Even that video, linked to above, does not seem to understand the true problem.

But where the deck plate and tendon are separate pieces (eg. Chinook), the bottom metal bit of the tendon is free to rotate inside the 2-bolt base.

Basher
590 posts
12 Dec 2021 11:56AM
Thumbs Up

Select to expand quote
Faff said..

But where the deck plate and tendon are separate pieces (eg. Chinook), the bottom metal bit of the tendon is free to rotate inside the 2-bolt base.


I never said it wasn't.
People buy a two bolt system because they think it's solving a problem. In fact it's usually just covering up a problem.
All systems are OK as long as the bearings work both sides of the U/J - and a lot of people don't realise how important that is.

I personally don't like the two bolt system because you lose mast track range and you can't shift the mast foot quickly. The lower disconnect point can also cause unnecessary problems and is usually an unneeded wear point.

PhilUK
1098 posts
12 Dec 2021 7:00PM
Thumbs Up

I've had a mastbase slide because I didnt tighten it up enough, like Mr Cucci said in the video. Luckily it slid forward. If you adjust the mastbase in the water you cant always do it up as tight as on land an sometimes its a pain to go back in again. They should make all plates with a tab.

Grantmac
2317 posts
13 Dec 2021 3:40AM
Thumbs Up

I've gone from 2 bolt to 1 bolt and back because of rig separation. I really miss having the adjustment range of the 1 bolt to the point of thinking I might fabricate a stopper for the track in order to use them safely again. I hadn't thought of attaching it to the plate though which is a pretty good idea.

WillyWind
579 posts
13 Dec 2021 11:13AM
Thumbs Up

Some boards tracks have a notch on the opening that prevents a loose mast base from coming out of the track. In order to remove the mast base you need to unscrew the base many turns. I find that safety feature pretty simple and clever. I have two boards with that type of track but never had my one bolt base to come loose.

WillyWind
579 posts
13 Dec 2021 11:16AM
Thumbs Up




John340
QLD, 3363 posts
13 Dec 2021 2:56PM
Thumbs Up

Select to expand quote
WillyWind said..
Some boards tracks have a notch on the opening that prevents a loose mast base from coming out of the track. In order to remove the mast base you need to unscrew the base many turns. I find that safety feature pretty simple and clever. I have two boards with that type of track but never had my one bolt base to come loose.


I've always used single bolt mast bases and in 40 years of windsurfing I've had one come loose once. My error in rushing rigging, which I've never made again.

Imax1
QLD, 4925 posts
13 Dec 2021 5:30PM
Thumbs Up

Select to expand quote
WillyWind said..



Chinook do this , its a good idea .

firiebob
WA, 3172 posts
13 Dec 2021 3:37PM
Thumbs Up

Select to expand quote
WillyWind said..
Some boards tracks have a notch on the opening that prevents a loose mast base from coming out of the track. In order to remove the mast base you need to unscrew the base many turns. I find that safety feature pretty simple and clever. I have two boards with that type of track but never had my one bolt base to come loose.


Same, all my Carbon Arts are like that.

lwalker
69 posts
21 Dec 2021 1:43AM
Thumbs Up

I had a single bolt come loose, slide forward and pop out the front of the track. This was 20 years ago on an F2 Xantos. I think the tracks they used had a flimsy plastic piece at the front. I was unbelievably lucky that a buddy was just behind me and grabbed the board before it went too far. I switched to 2-bolt bases the next day and have used them ever since, even though I don't think I've ever had a board with such a crappy mast track again.



Subscribe
Reply

Forums > Windsurfing General


"Mast base" started by choco