I am about to take the plunge and go RDM with some of my sails, so I'll need an RDM extension. I have not bought an extension in years so I have forgotten some of the things I didn't like about some of them.
I want one with 3 pulleys
I do not like the pin and collar system
I need Europin
Severnes rig on the wrong side
KA sails, so sail block is perpendicular to the mast
Any other pitfalls to look out for other than length?
Which brands fit my criteria above?
I've got both aluminium Streamlined and Severne Euro pins. Yes Severne rigs on wrong side to almost every other sail but it never bothers me. Severne pulleys are parallel with extension, Streamlined pulleys are perpendicular to extension, so depends on how the sail block is orientated. Yet again I don't have any preference with extension to sail pulley orientation. Severne base is easy to get foot pressure onto when downhauling but streamlined one is incredibly small and it took a while for my feet to get used to the point loading (which would you prefer someone to stand on you in - high heels v flat shoes) after changing over. Streamlined are fairly rudimentary but solid with shortest extension being 6cm and external pin lock (hook) doesn't allow much room for tieing off downhaul and tensioning tack strap . Severne probably the pick of the two although have noticed greater level of corrosion with it compared to teh Streamlined.
I have SDM carbon extensions but stayed clear of carbon RDMs after hearing that they were prone to breaking easier than SDM ones. I'd like to hear from anyone using carbon RDM extensions on their experience regarding breakages?????
I've got a carbon Chinook for my skinnies and haven't had a problem.
Maybe I'm just really gentle with my gear!!!
Select to expand quoteGaz45 said..
I've got a carbon Chinook for my skinnies and haven't had a problem.
Maybe I'm just really gentle with my gear!!!
Gaz, I have two Chinook carbon SDM extensions and they're great. Might revisit getting an RDM carbon ext. in near future.
I have 2 Severne extensions which I use with my KARace Sails. The centre lines of the sail and extension pulleys are at 90 degrees to each other. Once you learn the trick to threading the down haul line so the rope doesn't cross over then they work a treat.
Some of our team members have RDM NP extensions and they also work very well
Select to expand quoteGaz45 said..
I've got a carbon Chinook for my skinnies and haven't had a problem.
Maybe I'm just really gentle with my gear!!!
+1
Had it for long long time, still good as 
If you are willing to reconsider the pin and collar type, these alloy extensions from RADS work really well for me and are relatively inexpensive.http://www.sunshinecoastsailboards.com.au/shop/components/sail-components/mast-extensions/radz/radz-rdm-euro-pin-aluminium-detail
Euro pin system
Two pulleys that run well
A really good cleat that works well with downhaul cranks
Easy to adjust and simple reliable pin system
Allows collar to be removed for very short extension if needed.
I have never seen the need for carbon extensions. The weight is right down low where you don't feel it and I think alloy is a bit more durable/reliable in this situation.
Note the threading has no crossovers or extra friction with right angle pulley orientation.
^^^ Severne rig upside down - the pulley block is a mirror image to most. Most sails rig with clew to left as you downhaul, theirs are other way around due to prevailing wind in WA summer
Hard to explain........ hard for me as I have one of each type and can't remember the complicated threading order to rig a Severne in my normal orientation (ie: the extension is upside down when rigging)
Clear as mud?
Chinook alloy europin. Done heaps of open water ks on them and never had a problem.
Select to expand quoteikw777 said..
Chinook alloy europin. Done heaps of open water ks on them and never had a problem.
Agree chinook ..had a alloy38 for 6-8 years ...very strong .good quality..
Select to expand quoteMark _australia said..
^^^ Severne rig upside down - the pulley block is a mirror image to most. Most sails rig with clew to left as you downhaul, theirs are other way around due to prevailing wind in WA summer
Hard to explain........ hard for me as I have one of each type and can't remember the complicated threading order to rig a Severne in my normal orientation (ie: the extension is upside down when rigging)
Clear as mud?
yep same as P7, confusing on slalom sails, not so much on regular no cam sails.
I find it more conveniente to use one with the cleat that is undone just by pulling up, not parallel to the base, same as the one in sailquick's picture.
It took me a while to work out the best threading sequence with my KA "perpendicular" pulley system on a severne wave grenade base. The threading is not sequential across the three pulleys. I still get confused when rigging with the sail laying the other way. Can't coment on other bases.
Select to expand quoteMark _australia said...
^^^ Severne rig upside down - the pulley block is a mirror image to most. Most sails rig with clew to left as you downhaul, theirs are other way around due to prevailing wind in WA summer
Hard to explain........ hard for me as I have one of each type and can't remember the complicated threading order to rig a Severne in my normal orientation (ie: the extension is upside down when rigging)
Clear as mud?
I'm curious because I've just bought a severe after only using prydes over recent years and the prydes rig with clew on the left. So a 2016 ncx will rig with clew to the right?
Select to expand quotepowersloshin said..
I find it more conveniente to use one with the cleat that is undone just by pulling up, not parallel to the base, same as the one in sailquick's picture.
yes, that is good. Add that to my list of requirements please.
Also needs to be useable with a winch. Can the above type be used with a winch?
Select to expand quoteWindxtasy said..powersloshin said..
I find it more conveniente to use one with the cleat that is undone just by pulling up, not parallel to the base, same as the one in sailquick's picture.
yes, that is good. Add that to my list of requirements please.
That has a seat for the tack strap too.
Select to expand quoteOrange Whip said..Mark _australia said...
^^^ Severne rig upside down - the pulley block is a mirror image to most. Most sails rig with clew to left as you downhaul, theirs are other way around due to prevailing wind in WA summer
Hard to explain........ hard for me as I have one of each type and can't remember the complicated threading order to rig a Severne in my normal orientation (ie: the extension is upside down when rigging)
Clear as mud?
I'm curious because I've just bought a severe after only using prydes over recent years and the prydes rig with clew on the left. So a 2016 ncx will rig with clew to the right?
yes
Select to expand quotesausage said..
I have SDM carbon extensions but stayed clear of carbon RDMs after hearing that they were prone to breaking easier than SDM ones. I'd like to hear from anyone using carbon RDM extensions on their experience regarding breakages?????
Snags, you might be on to something.
I crashed and disintegrated a Streamlined Featherline Carbon RDM Pin 48cm Extension into about 20 pieces about a year ago.
I use the alloy version now. The cleat is horrible, otherwise it seems tough.
I snapped a Chinook in very heavy shorebreak once, so I took it back as it has awesome warranty. Had a new one, and it's been going strong for 2+ years. I have bent so many aluminium RDM extensions I would'nt go back.
As for Severne sails rigging backwards, I don't get what the issue is. I rig the sail whichever way I have unrolled it! Maybe it's because I sail port tack as often as starboard....
Select to expand quoteMark _australia said..
^^^ Severne rig upside down - the pulley block is a mirror image to most. Most sails rig with clew to left as you downhaul, theirs are other way around due to prevailing wind in WA summer
Hard to explain........ hard for me as I have one of each type and can't remember the complicated threading order to rig a Severne in my normal orientation (ie: the extension is upside down when rigging)
Clear as mud?
Is that because you always have to rig facing the sea?
I have np skinny extensions carbon and ali.
The ali ones can bend if used close to max extention- the carbon ones are bullet proof.
I also have standard np extensions and I also have a standard severne extension.
The severne is poorly designed imo
-the sdm version has a collar that tends to grab the soft material in the tack when you release the downhaul and thus rips it (used on a reflex)
-pulley alignment for your kas are wrong
-you actually need to thread the pulleys on the severne extension unlike loop and go on the np
-not sure of the severne skinny but it may have more purchase with another block-which makes it easier to down haul but slower to rig and more line to stow
-un cleating at the end of the sail may be harder if the cleat is similar to the sdm extension ie you prob need to sit on the grd to un do instead of
standing as you can with the np.
I am currently using a north 2.0 ratchet extension on my ka's its early days but these work very well...
I would recommend the np carbon skinny extention
or the north ratchet equiv
Select to expand quoteikw777 said..
You guys, it IS possible to rig a sail either way up you know!
Not one with cams and zip pockets!
Select to expand quotesausage said..ikw777 said..
You guys, it IS possible to rig a sail either way up you know!
Not one with cams and zip pockets!
Yep. 'Possible' but definitely a major PITA!!
If you can find a sail that has the luff spec the same as the mast length you do not need an extension.
My 7m has a 454 cm luff- but I like 5-6 cm over so perfect. I use a plastic base that weighs in at 150g including rope instead of a 300-400g extension.
Select to expand quotepetermac33 said..
If you can find a sail that has the luff spec the same as the mast length you do not need an extension.
My 7m has a 454 cm luff- but I like 5-6 cm over so perfect. I use a plastic base that weighs in at 150g including rope instead of a 300-400g extension.
Thats nice.
But I have 5 sails.
Select to expand quotesausage said...ikw777 said..
You guys, it IS possible to rig a sail either way up you know!
Not one with cams and zip pockets!
What's a "cam"? And why would a sail have zips??? 
