if a sail says it takes a 460 mast,would it b alright to use a 430 mast and have the mast extention fully extended

If the mast extension is 30cm long or longer yes. 430 mast plus extension set to 30cm = 460 but the luff length most likely is more than 460 this is the measurement you need to consider because it may be something like 482 which means you would need the extension set to 52cm (482-430) and extensions aren't usually that long. So read what the luff length on the sail is and tell us how long your extension is and put it on here and someone will tell you if a 430 will work or not.

yea the luff is 476 and my extension is 48,but im just a bit worried it might weakin the mast having not having much extension in the mast

If it is a 48cm extension it is designed to work on 48cm and have enough in the mast. It will not weaken the mast.

However, 46cm of extension is very unlikely to work well as it effectively makes the mast softer. Main thing is it will twist off too easily.
If you are a lightweight it may work OK

The extension is made to go to 48cm and has a certain amount left above the longest adjustment for a reason. That's the minimum needed to go in the mast so if your using and compatible mast and base therefore shouldn't really be an issue. In theory the mast should actually work better as far as flexing goes with less extension inside it because if you you had that extension set at say 2cm it would have 46cm in the mast stopping that area from flexing. But like Mark says it may flex to much.

i weigh about 75kg would this be alright

I meant lighter than average and considering sail size vs conditions.

I don't reckon you are much lighter than average, plus it is not ideal sail setting so it may be bloody awful.

It may well be OK if it is the same manufacturer's mast, hard to say til you try it

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qldnacra said...
In theory the mast should actually work better as far as flexing goes with less extension inside it because if you you had that extension set at say 2cm it would have 46cm in the mast stopping that area from flexing. But like Mark says it may flex to much.

In practice, however, 48cm of mast extension remains 48cm of stiff mast, whether inside or out. A 4.0m mast with a 48cm extension set to 45cm will have a slightly different bend characteristic to a 4.3m mast with a shorter (30cm or less - I don't know how short they come) extension set to 15cm. Likewise, the same mast with a 48cm extension set to 15cm will bend differently to the same mast with a 30cm (or less - I don't know how short they come) extension set to 15cm. I must admit though, I can't see it making a whole lot difference for all we plebs.

so that means it should b aright then

how many times and ways you need this question answered?

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jezdog said...

so that means it should b aright then

if its a free ride or wave sail then it will probably be fine.
Race sails are more mast critical.
Just try it,nothing to lose.

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slalomfreak said...

jezdog said...

so that means it should b aright then

.
Just try it,nothing to lose.

but before you buy it..........

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dinsdale said...

qldnacra said...
In theory the mast should actually work better as far as flexing goes with less extension inside it because if you you had that extension set at say 2cm it would have 46cm in the mast stopping that area from flexing. But like Mark says it may flex to much.

In practice, however, 48cm of mast extension remains 48cm of stiff mast, whether inside or out. A 4.0m mast with a 48cm extension set to 45cm will have a slightly different bend characteristic to a 4.3m mast with a shorter (30cm or less - I don't know how short they come) extension set to 15cm. Likewise, the same mast with a 48cm extension set to 15cm will bend differently to the same mast with a 30cm (or less - I don't know how short they come) extension set to 15cm. I must admit though, I can't see it making a whole lot difference for all we plebs.

The moral of the story is basically that long extensions suck and are a poor substitute for the correct mast and base. They may work but will never be ideal. Can we agree on that and hope the guy gets the idea

no worries champ got the idea,just wanted to make sure, not all rich enough to buy lots of gear