Mast, mast, mast!

Windsurf equipment based chatter should be in here.
TOTD
Posts: 182
Joined: Fri Nov 23, 2018 4:33 pm
Has liked: 1 time
Been liked: 29 times

Re: Mast, mast, mast!

Post by TOTD » Fri Sep 20, 2019 2:17 pm

Gorgesailor wrote:
Thu Sep 19, 2019 7:16 pm
TOTD wrote:
Thu Sep 19, 2019 2:03 pm
Mast stiffness vs. sailor’s weight:
Some people think a heavier person should use a stiffer mast and a lighter person a softer mast. This is kind of true and kind of not true. The mast stiffness must be matched to the sail size, not the person’s weight. So generally, a heavier person is using a bigger sail, so they will be on a longer and stiffer mast.
This is not quite true either. For example, if the heavier person is sailing a 5.0 in 25knot wind while the lighter person is sailing it in 15knots(extreme example) the heavier person is putting a greater load on the mast than the light person. So PadIoW is right in that way. Thing is the mast curve, & load distribution of sails of different size is & should be different so stick the same mast in a 5.0 & 4.0 is possible but not necessarily a good thing.

I like the rabbit hole , analysis, mentioned above.
Gorgesailor, I don’t understand what part of my post you missed, the part about true and kind of untrue obviously.
That passage is a reflection of some designer in Hawaii.
K4 4Boards Tri Sails,and Chocolate Chip cookies
Ibuprofen, Irish Whiskey

Richarli
Posts: 111
Joined: Tue Nov 13, 2018 8:01 pm
Has liked: 5 times
Been liked: 18 times

Re: Mast, mast, mast!

Post by Richarli » Fri Sep 20, 2019 4:30 pm

I sort of get what everybody is trying to say and I think we're all heading in the right direction if not starting from the same point.
However in my personal experience I would suggest I'm using a sail in much more wind than the size and weight it was designed for. Therefore if I use the manufacturer designated mast it's going to be too soft?

TOTD
Posts: 182
Joined: Fri Nov 23, 2018 4:33 pm
Has liked: 1 time
Been liked: 29 times

Re: Mast, mast, mast!

Post by TOTD » Sat Sep 21, 2019 2:20 pm

Richarli wrote:
Fri Sep 20, 2019 4:30 pm
I sort of get what everybody is trying to say and I think we're all heading in the right direction if not starting from the same point.
However in my personal experience I would suggest I'm using a sail in much more wind than the size and weight it was designed for. Therefore if I use the manufacturer designated mast it's going to be too soft?
Possibly, it will be too soft. Such a determination would be difficult, I don’t know how.

If you knowingly use a large sail for winds it’s not designed for, you don’t have smaller? Such a scenario would dictate a lot of downhaul, thus a negative effect on handling, not so good.
K4 4Boards Tri Sails,and Chocolate Chip cookies
Ibuprofen, Irish Whiskey

Richarli
Posts: 111
Joined: Tue Nov 13, 2018 8:01 pm
Has liked: 5 times
Been liked: 18 times

Re: Mast, mast, mast!

Post by Richarli » Sat Sep 21, 2019 4:28 pm

Sorry I didn't explain myself better. I meant me at 100kg using the sail in a higher wind strength than the 75kg sailor it was designed for.

TOTD
Posts: 182
Joined: Fri Nov 23, 2018 4:33 pm
Has liked: 1 time
Been liked: 29 times

Re: Mast, mast, mast!

Post by TOTD » Sun Sep 22, 2019 1:00 am

Richarli wrote:
Sat Sep 21, 2019 4:28 pm
Sorry I didn't explain myself better. I meant me at 100kg using the sail in a higher wind strength than the 75kg sailor it was designed for.
This is the best answer I came up with.


Mast stiffness vs. sailor’s weight:
Some people think a heavier person should use a stiffer mast and a lighter person a softer mast. This is kind of true and kind of not true. The mast stiffness must be matched to the sail size, not the person’s weight. So generally, a heavier person is using a bigger sail, so they will be on a longer and stiffer mast.

THe remark about lighter sailer designer for vs heavier one using it, does not compute in my mind.
I think I might have several masts that fit this sail, just in case.
K4 4Boards Tri Sails,and Chocolate Chip cookies
Ibuprofen, Irish Whiskey

Jeroensurf
Posts: 22
Joined: Fri Oct 11, 2019 2:49 pm
Has liked: 11 times
Been liked: 17 times

Re: Mast, mast, mast!

Post by Jeroensurf » Sat Oct 12, 2019 8:05 am

A bit late to join the party but...
Besides the mast stiffness you have also seamshaping to deal with. The problem is that that more or less has to be in sync with the expected load tension set by the mast. That is why you only have a few cm/kg of downhaul range and often more Outhaul range. So you can,t think about the sail as indepenend thing, its always about the rig.
Because of this profile I believe that most sails/rigs have a sailor weightrange they work best with. This comes often with a diff feel of the sails/rigs and if you really like the feel most of us accept the slightly smaller windrange as compromise to keep that feel.

Within this range you can play a bit. With some Hotsails in the past was a 400 mast adviced but with my very moddest 93kg a preffered it with a 430 base and 4m top to put a bit more tension in the bottom of the sail, but a whole 430 would make the sail too stiff.

There has also been examples of weight specific sails, for example the Hot Dwag/DD was a sail that was especially made light (sub 70kg) sailors.
The 5.8 was rigged on a 400 mast and the seamshaping fitting that. My wife was back then still windsurfing and loved it. For me it was unbalanced and the Cof E allover the place. I tried it with a 430 mast and there was more wrinkle as sail left.

Back to the weight/range: right now i,m on the 2020 Ezzy ails and got a wave(the new Elite) in 5.8 and 3.7 and Taka5.3-4.7-4.1.
The Wave will be more stable and probably more suited to my weight, but because I like the soft feel of the Taka i,m happy to trade a bit of range and that I need to trim more often my sail for that feel and depowering on the wave because it suits my likings/needs.

TOTD
Posts: 182
Joined: Fri Nov 23, 2018 4:33 pm
Has liked: 1 time
Been liked: 29 times

Re: Mast, mast, mast!

Post by TOTD » Tue Oct 15, 2019 5:11 pm

Late or not, good post.
Me, on HSM and Ezzy and Custom TriSails, UK, find that all different , somehow feel the same, odd statement by my feelings.
I tried the NAISH Chopper, one of those designed for the same mast, with only a few cm out the head, sail was past it’s sail by date some, semi clapped out, was light and made decent power.
I prefer the Taka to the Elite, again odd but the QU4D to the KS series from HSM .
K4 4Boards Tri Sails,and Chocolate Chip cookies
Ibuprofen, Irish Whiskey

User avatar
justwan naride
Posts: 7
Joined: Thu Oct 03, 2019 10:49 am
Has liked: 10 times
Been liked: 10 times

Re: Mast, mast, mast!

Post by justwan naride » Thu Oct 17, 2019 10:59 am

Although probably not commercially viable, I think there may be merit to the rider weight/mast stiffness concept. For example, my old favourite Aerotech Charge 4.5 is supposed to work best with a 400 mast. Luff length is such though that with a long extension it can be rigged with a 370 as well. I've tried both and it turns out that for my 69kg the sail feels better across a wider wind range on the 370 mast. Maybe it was designed/tested by heavier people on a 400?

I feel that the softer/shorter mast allows it to work with less downhall than recommended in light conditions (while still "breathing" in gusts due to the softness) and depowers more efficiently at the upper wind range again due to the softer mast. Last Saturday was one of these days that the wind changed both in speed and direction often and I had to tune rig and board a few times. I was impressed by the range the equipment offered, given that there were people on 4.2s and 5.3 on the water and most complained about the unstable conditions. Meanwhile, I managed to both plane 95% of the session and not struggle with the gusts at the same time.

That said, I own 3 masts (370,400,430) to cover my quiver of 3.7, 4.5, 5.2 and 5.9 sails, and ideally I'd like a 340 as well in order to get the smaller sail's full range. If I was building my quiver from scratch I'd be looking for ways to cover the same range with 2 masts.

TOTD
Posts: 182
Joined: Fri Nov 23, 2018 4:33 pm
Has liked: 1 time
Been liked: 29 times

Re: Mast, mast, mast!

Post by TOTD » Fri Oct 18, 2019 2:34 pm

justwan naride wrote:
Thu Oct 17, 2019 10:59 am
Although probably not commercially viable, I think there may be merit to the rider weight/mast stiffness concept. For example, my old favourite Aerotech Charge 4.5 is supposed to work best with a 400 mast. Luff length is such though that with a long extension it can be rigged with a 370 as well. I've tried both and it turns out that for my 69kg the sail feels better across a wider wind range on the 370 mast. Maybe it was designed/tested by heavier people on a 400?

I feel that the softer/shorter mast allows it to work with less downhall than recommended in light conditions (while still "breathing" in gusts due to the softness) and depowers more efficiently at the upper wind range again due to the softer mast. Last Saturday was one of these days that the wind changed both in speed and direction often and I had to tune rig and board a few times. I was impressed by the range the equipment offered, given that there were people on 4.2s and 5.3 on the water and most complained about the unstable conditions. Meanwhile, I managed to both plane 95% of the session and not struggle with the gusts at the same time.

That said, I own 3 masts (370,400,430) to cover my quiver of 3.7, 4.5, 5.2 and 5.9 sails, and ideally I'd like a 340 as well in order to get the smaller sail's full range. If I was building my quiver from scratch I'd be looking for ways to cover the same range with 2 masts.
I don’t find your results out of ordinary, remarkable , while your weight is on the lower end of the scale, I think it’s more the subjective feeling defines how it feels to you. The mast itself will have some influence. Not such a easy peasy subject matter.
With some careful selection a quiver may like yours would work on A reduction of mast inventory . I have not been pleased with too long or too short in the mast dept.
K4 4Boards Tri Sails,and Chocolate Chip cookies
Ibuprofen, Irish Whiskey

jamz
Posts: 29
Joined: Sun Nov 25, 2018 7:44 pm
Has liked: 5 times
Been liked: 5 times

Re: Mast, mast, mast!

Post by jamz » Sat Oct 19, 2019 6:25 am

One thing that hasn't been mentioned in this thread is using the correct mast but not the optimum style (RDM/SDM). I have one sail in my quiver which I rig on the correct mast but use the alternative RDM style since this mast is used for two of my wave sails. Unsure what the pros / cons are? I have settled on increasing settings by +2cm over the recommended figures for the downhaul and outhaul to compensate for the reduced diameter of mast in the luff tube. I think using the RDM mast makes the shape of the sail slightly deeper as there is more material spare in the luff tube so creates a bit more power. The only downside is if I drop the sail there is more space in the luff tube for water to fill and therefore slightly heavier to get out of the water to water start.

Post Reply