In praise of SDM masts

[Floyd]

Davide
The thread is
In praise of SDM masts
I didnt say RDM dont suit sailors over 100k,they obviuosly suit some; but not many.Basically those using sails specifically designed for RDM`s !! i

Totally agree with unreg posters comments re IMCS been very flawed. There is just no way a 430 RDM is as stiff as a 430 SDM ; but perhaps I`m wrong .

[davide]

Originally Posted by Floyd

But then I might have been wrong assesing my sails over last 30+ years sailing ! I should sell my SDM`s and buy RDM`s and put up with the poorer range;less stability and worse top end they give MY SAILS !

Totally agree with unreg posters comments re IMCS been very flawed. There is just no way my 430 RDM is as stiff as my 430 SDM ; but perhaps I`m wrong with that too !! Davide Knows best ???

PS Buy a dictionary and look up RANGE.

Weeeeee! Nice flurry of unpleasantries, bordering on personal attacks ... classic e-mail syndrome and this is when I stop chatting on a forum, I am sorry I got trapped in this silly thread. RDMs or SDMs is all good ... let's just enjoy sailing: great day today at Crissy! and tomorrow is another 20 knots+

Originally Posted by Floyd

Davide
I said they dont suit my sails; Neil Prydes;

well there is your mistake
you should get some decent sails and you wouldnt have any more problems

there is no problem with IMCS, there is a problem with bullshit marketing which prints numbers that are not real.
Most RDM masts are softer in the base/boom area than most SDM masts.
If you then use a soft based RDM in place of a stiff based SDM it will flatten the sail in a way as described by Floyd and others.
Some SDM masts are flexy in the bottom and stiff in the top and bend much like most RDM masts.
Some RDM masts are stiff in the base and flexy in the top and bend much like most SDM masts.

And Davides` unpleasantries ???

"and it is really a no brainer which one to choose in the waves or B&J."

"and if a mast feel too soft with a lot of extension for a 105Kg it just means ... it is the wrong mast for the application"

"I personally wish RDMs were the industry standard: this sport can use some simplification! "

"Whatever ... you are 105Kg and you are basing your conclusion on one mast that does not fit you."

"It is the thickness that makes RDMs masts so strong"

"sails do not rig more flat on a RDM (or fatter on a SDM, sigh ..). "

"BTW to talk of RDM vs SDM is actually silly."

No wonder Floyd was a bit unpleasant !!!

They dont suit my Rocks either !!! And they are supposed to !!!

[nakaniko]

For sure I never wanted to cause an argument between us windsurfers, I only wanted to tell what nowday few people tell, that SDM in some situations have some advantages in the most common situations for us windsurfers, that is to say free sailng in bays and lakes; for sure strength and handling in waves are best in RDM.
Davide, as I can read on the instructions booklets given with "our" (fantastic) HSM sails, JH tells that we can use on them both SDM and RDM, changing the sail response that is more steady and bump&jump with sdm and more loose and forgiving with rdm. So I simply do both things, and because of the well known lack of often wave conditions of the unlucky north east of Italy, at the end are the SDM that are mostly used: 16 days of sailing, 16 sdms days.
As told, selling the SDM I would have get 100-150 euro for three masts which had total retail price of about 1.000 euro, so choice of keeping them was obvious. And so I have a spare mast in case of a breackage.
I know that the more the time pass, the less easier is that sailmaker keep on making sail really compatible with SDM, but this imho is a mistake, as masts can lasts for 20 years and more, so this way you close the door to a lot of people wanting to learn windsurf end buying stuff used at cheap price, like on much places in the world. I don't think sending out of market the SDM would help windsurfing, imho...
HSM are really compatible with SDM, other brand's sail they tell me that trying to rig them - even stated compatible - on a SDM is a nightmare (some Simmer's f.e.). Also between my 2008 HSM the difference is noticeable, little hard with Fires, good with Smacks, very good with the Superfreak (because it's 8,0?)
So, as seems to be clear that SDMs stil their advantages in many situations and for some kind of riders, why not keeping the compatiblity? We are the ones that finally cause the choiches of the brands, so imho we have to choos brands that give this opportunity, leaving the others in the stores unsold!
BTW, unreg, I don't find real unpleasantries in Davide's words, it's simply a point of wiew.

[Floyd]

There is an industry standard. Its called SDM. Standard Diameter Mast.(or there used to be!)

[Floyd]

The Grand Prix Speed is designed to be used only with RDM masts .

The GPS is designed for the Hot Rod RDM mast, but is SDM compatible, supplied with an extra set of cambers.

Both above comments taken from Hot Sails site. Same sail,same year,one in main web part other in PDF rigging guide !!!

Not very helpful !!!

[Floyd]

Standard diameter (SDM) or reduced diameter (RDM)?

RDM – Advantages:

•Thinner in the hands, many prefer this feel in transitions where the mast is held.
•Thicker wall, more durable
•Relatively softer in the middle for a springy feel
•More suited to wave & freestyle applications


SDM – Advantages:

•Lighter for a given stiffness
•Range of top section stiffness available for speed/slalom applications
•First choice for camber induced sails
•More locked in feel with better top end performance
•More suited to freeride, slalom, racing and speed applications.
•Floats better for easier water starting


Generally speaking it’s obvious that the SDM is the natural choice for larger sails, for speed, slalom, and light/medium wind freeride. Conversely, the RDM is popular with wave and freestyle sailors.


Lifted from Tushingham site !!!