Hi,
Snapped my mast (520 RSX) at a competition while rigging, would it possible for me to cut the frayed carbon off and make it into a small rig mast? (as i only snapped a metre of the mast)
This could also be topic for broken mast cut down in general.

There's 4 places you could loose 1m off a mast and each place would deserve a different answer.
More info, possibly a pic would be helpfull

If you cut off the top 1m then the mast will be too stiff for the smaller sail. If you cut off the bottom, you may not fit the mast extension in the reduced diameter of the new bottom.

But give it a try and see how it works

I lost about half a metre off the tip of a mast, tried rigging a small sail to it and was surprised to see it fitted better than before. Although a little stiff it worked well and I still apart of my quiver.

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John340 said..
If you cut off the top 1m then the mast will be too stiff for the smaller sail. If you cut off the bottom, you may not fit the mast extension in the reduced diameter of the new bottom.

But give it a try and see how it works

I have snapped the bottom , it would be possible for me to put carbon inside the tube so it fits an rdm?

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Siclone said..
I lost about half a metre off the tip of a mast, tried rigging a small sail to it and was surprised to see it fitted better than before. Although a little stiff it worked well and I still apart of my quiver.

ok cool thanks, its a full carbon rig so ig it shouldn't go to waste

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Roy1000 said..

John340 said..
If you cut off the top 1m then the mast will be too stiff for the smaller sail. If you cut off the bottom, you may not fit the mast extension in the reduced diameter of the new bottom.

But give it a try and see how it works

I have snapped the bottom , it would be possible for me to put carbon inside the tube so it fits an rdm?

Yes but expensive. You need a fitted carbon sleeve which in Sydney you would usually buy from CST or C-tech (NZ). We did it with Flying 11 masts to stiffen them while staying within the class rules. It might not be worth it unless it magically fits a standard size tube.

Or you could just buy a slightly oversized tube and sand your life away, depends how much you value your time.

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SaltySkiffies said..

Roy1000 said..

John340 said..
If you cut off the top 1m then the mast will be too stiff for the smaller sail. If you cut off the bottom, you may not fit the mast extension in the reduced diameter of the new bottom.

But give it a try and see how it works

I have snapped the bottom , it would be possible for me to put carbon inside the tube so it fits an rdm?

Yes but expensive. You need a fitted carbon sleeve which in Sydney you would usually buy from CST or C-tech (NZ). We did it with Flying 11 masts to stiffen them while staying within the class rules. It might not be worth it unless it magically fits a standard size tube.

Or you could just buy a slightly oversized tube and sand your life away, depends how much you value your time.

I dont value it much haha, i've got loads of old rigs i could shove in, or i could sand down the inside of the tube to fit an sdm?

I've done the opposite, fitted a slightly reduced mast that had a broken base into an SDM broken base. It works surprisingly well. I even got PBs speeds using it.

I broke my RRD Firewig 430 100 percent two feet below the boom last month.

I overlapped the bottom piece with what is left of the top piece of the bottom half and is now a 375 mast.

The fit is so secure. Impossible now to remove.

Not tried it yet. 1.5kg.

Free to good home

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Roy1000 said..

John340 said..
If you cut off the top 1m then the mast will be too stiff for the smaller sail. If you cut off the bottom, you may not fit the mast extension in the reduced diameter of the new bottom.

But give it a try and see how it works

I have snapped the bottom , it would be possible for me to put carbon inside the tube so it fits an rdm?

No

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Pcdefender said..
I broke my RRD Firewig 430 100 percent two feet below the boom last month.

I overlapped the bottom piece with what is left of the top piece of the bottom half and is now a 375 mast.

The fit is so secure. Impossible now to remove.

Not tried it yet. 1.5kg.

Free to good home

You have got to ask yourself if it's worth the potential swim when it breaks.

I guess it depends on the overlap, I mean you guys all trust your two piece masts don't you?

Isn't the bottom and the boom area strengthened. Would this now be out of whack?

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decrepit said..
I've done the opposite, fitted a slightly reduced mast that had a broken base into an SDM broken base. It works surprisingly well. I even got PBs speeds using it.

So you snapped the base of the mast but then found another mast bottom and sleeved it?

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John340 said..

Roy1000 said..

John340 said..
If you cut off the top 1m then the mast will be too stiff for the smaller sail. If you cut off the bottom, you may not fit the mast extension in the reduced diameter of the new bottom.

But give it a try and see how it works

I have snapped the bottom , it would be possible for me to put carbon inside the tube so it fits an rdm?

No

Thanks

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Pcdefender said..
I broke my RRD Firewig 430 100 percent two feet below the boom last month.

I overlapped the bottom piece with what is left of the top piece of the bottom half and is now a 375 mast.

The fit is so secure. Impossible now to remove.

Not tried it yet. 1.5kg.

Free to good home

pop it up on the free forum im sure someone will take it pos a beginner

Hijacking this thread, I have a damaged bottom half that dragged along the road on the insert for the top half. Question is what's the minimum acceptable length for this now it's a bit shorter. It's a great mast that I'd really like to be able to use. Maybe for a light weight not me. It's a NP SDM 430.

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BSN101 said..
Hijacking this thread, I have a damaged bottom half that dragged along the road on the insert for the top half. Question is what's the minimum acceptable length for this now it's a bit shorter. It's a great mast that I'd really like to be able to use. Maybe for a light weight not me. It's a NP SDM 430.

Surely you could have the pointy bit facing forward so the load is on the longest bit , then it wouldn't make much of a difference?
also how did this happen?!?

I would cut it off even so it does not apply uneven pressure to the top piece, but you should contact the manufacturer to see what they say, want to make sure the reduced contact area with top section does not cause increased loading on the top section, which could cause it to fail.

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Roy1000 said..

BSN101 said..
Hijacking this thread, I have a damaged bottom half that dragged along the road on the insert for the top half. Question is what's the minimum acceptable length for this now it's a bit shorter. It's a great mast that I'd really like to be able to use. Maybe for a light weight not me. It's a NP SDM 430.

Surely you could have the pointy bit facing forward so the load is on the longest bit , then it wouldn't make much of a difference?
also how did this happen?!?

I agree with the above idea . As long as the long part is close to original length . I would resin a plug , halfway down the end with something solid so the tip doesn't deform . Keeping in mind , there is also a lot of sideways flex .

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Imax1 said..

Roy1000 said..

BSN101 said..
Hijacking this thread, I have a damaged bottom half that dragged along the road on the insert for the top half. Question is what's the minimum acceptable length for this now it's a bit shorter. It's a great mast that I'd really like to be able to use. Maybe for a light weight not me. It's a NP SDM 430.

Surely you could have the pointy bit facing forward so the load is on the longest bit , then it wouldn't make much of a difference?
also how did this happen?!?

I agree with the above idea . As long as the long part is close to original length . I would resin a plug , halfway down the end with something solid so the tip doesn't deform . Keeping in mind , there is also a lot of sideways flex .

How about shim the insert then either skim epoxy to make it the correct snug fit or a full epoxy plug to make a snug fit. Both options will leave the insert as it is.

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Roy1000 said.. >>>So you snapped the base of the mast but then found another mast bottom and sleeved it?

A mate snapped the base of a 2 piece SDM I had inherited a one piece MDM, that had also been snapped at the bottom, (don't know how, I've found these masts very close to indestructible, I've had mine since the mid 90s).
The base of the SDM was a good snug fit over the MDM, to get the mast length I needed, it's now about 380.
So the boom reinforcement lines up where it should be. There's plenty of overlap, so the whole thing is a bit heavier than standard.