very short mast extension for US base and RDM mast?

[teleclimber]

I need a really short extension to rig my 2007 Ezzy Infinity on the 490 mast I got with it. I use US bases.

It seems hard to find very short extensions. My Chinook extension only goes down to 10cm. The Infinity is 492, so I'd need 2cm. The head can be extended a bit so I could work with 5 or 6cm.

However I'm having a really hard time finding such an extension. It seems the Streamlined Feather-Line carbon Extension does go down to 6 cm (I presume by removing the collar and letting the mast rest on the larger aluminum part) but it costs more than what I paid for the sail + mast!

https://streamlined.us/feather-line-extension-01.html

Streamlined says their Aluminum extensions also go down to 6cm but looking at the pictures I have a hard time believing that: the last hole is 10cm, and even removing the collar it seems it only goes to 8cm. (I sent streamlined an email.)

Does anybody know of any other RDM-US-base extensions that are very short? It's OK if they are not adjustable. I've seen some for SDM, and some for RDM + Euro pin, but not RDM + US-base. ARgh!

Thanks, Oliver.

[manuel]

Recommended mast is 460 isn't it? 490 might be a bit stiff.

Yes streamlined goes to 6, you can also just fit the mast directly in the extension no collar. When you rig, what do you get? You have a vario top?

[cgoudie1]

does this not work for you?

http://shop.watersportswest.com/1064-chinook-stubby-3-base-ext

-Craig

[teleclimber]

[swchandler]

Have you thought about changing to a Euro-pin universal and extension?

[joethewindsufa]

the reason that Streamlined mast extension is over $200 is the carbon
aluminium extensions are about $100 less
my NP RDM aluminium XT34 has a minimum of about 5 cm - NOT Euro
(measured top of collar to just above the extension pulleys)

now that i measured, i see the numbers are off by 1+ cm
that is why one says to always measure
NO wonder I never fully downhauled that extension

tried SDM once without the collar and did NOT like it
NOT a snug connection

[manuel]

The vario top is there so that you can use the longer mast.

Other option is to use top of 490 and bottom of 460. That way you can use your 26-28cm extension without the need for a 45.

[isobars]

1. Is that 492 just a number printed somewhere, or have you verified by rigging that you really need just 2 cm between the base of the mast and the base of the extension?

2.Same question at the top. Most vario tops provide for a foot or two of adjustability.

3. I've rigged scores of brands and models of extensions, and do not remember any with only an inch (or 2 cm) between the bottom of the mast and the bottom of the extension. If nothing else, most extensions devote their first few inches to rivets or bolts holding parts together.

Mike \m/

[bred2shred]

Another option would be to carefully cut an inch or two off the bottom of the mast.

sm

[LeeD]

Chopsaw is the cleanest, quickest, easiest way to cleanly cut down a mast. Takes forever setting it up, takes 1.5 seconds to complete a perfect cut.