The MUF Delta XT-50 has arrived :) looking forward to getting them on the water unfortunately as always wind is not looking so good this week :(

MUF Say: The New Delta XT50 is aimed at riders who are looking for great speeds and need slightly less rake than our current Delta fins have. That will mean a reduction by about 5 % in rake to 50 degrees (instead of around 55). That means earlier planning and less sensitivity for back-foot pressure, generally easier handling / more comfort. The profile is also new and narrower resulting in higher end speeds. MUF will produce the delta XT50 in the sizes 10 cm to 30cm (in 2 cm steps, Powerbox, Tuttle and Deep-Tuttle).



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LOOKS the part ....might give this one a go in a smaller size than my 22 ''XT .which was brilliant at shark bay this year .

NICE rug . Persian ?

+1 on the rug and the fins look pretty good too. With slightly more rake than the original xt, size for size how did they compare in testing, would you still recommend a smaller fin than a standard delta as with the original xt.
That 10 cm looks dangerous, you could sail into ankle deep water with that. Scary.
Well done MUF.

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Tardy said..

NICE rug . Persian ?

Thanks but it is a fake one! Side of the road UAE special.

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Swindy said..
+1 on the rug and the fins look pretty good too. With slightly more rake than the original xt, size for size how did they compare in testing, would you still recommend a smaller fin than a standard delta as with the original xt.
That 10 cm looks dangerous, you could sail into ankle deep water with that. Scary.
Well done MUF.

Only got them yesterday so no chance to test them. As usual you get new gear to test and the wind vanishes .

I feel they will perform the same as a Delta XT. They are basically the same fin all they have done with the Delta XT-50 is move the fin a little more FWD thus increasing the rake it also slightly increases the surface area of the Delta XT-50. As you can see from the pictures below when you put a Delta XT-50 on top of a Delta XT it completely covers it.

There is a perception out there that you need a 50 degree fin to get through the think weed at spots like budgie but it was shown that when powered up the Delta XT had no problem getting through the weed proven by the fact the fin has done over 40knts at Budgie and done hundreds of km's through the thickest weed with the riders feeling there was not that much of an extra tug from the weed than a standard delta. However as perception is everything MUF decided to go along with my original suggestion and move the front forward increasing the rake thus put anyone's concerns about getting through thick weed to rest. So now we have a delta fin that performs much better in chop can be sailed around 2cm smaller than a standard delta and has enough rake to get through thick weed powered up or not. All this will give riders the confidence to push the limits and go fast.

I am interested to see the 10cm Delta XT-50 being used!

more Glass in the base than the foil. Know just the spot for that one. Probably need a twin fin though to get back up wind.

I thought MUF would have provided some test data but I suppose they don't have the conditions that Budgie and Mandurah have. The extra couple of deg rake and the increase in rake towards the tip could make quite a difference for the better. Look forward to hearing how they go when you get some wind.

Just picked up a 14 cm XT50 this morning from Legless, It is to use in my speed board in high wind conditions, I compared it to a tradition Delta "speed" 16cm the foil thickness was almost identical at 10.0mm. The rake as advertised is 50 degrees (compared to the 57 of the original Deltas). Good price too at less than $150

Just need 35 kts to test it

tbwonder I have my fingers crossed you get some wind to take it for a spin soon.

Ok. So the new ones have more rake than the previous..

Original Delta 55deg, XT 48deg, XT50 50deg ??

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Stretchy said..
Original Delta 55deg, XT 48deg, XT50 50deg ??

Yes that is correct.

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Stretchy said..
Original Delta 55deg, XT 48deg, XT50 50deg ??

Does 2 degrees of rake either way really make a noticable difference in
A. weed shedding
and B. safer riding with less spinout

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sailquik said..

Stretchy said..
Original Delta 55deg, XT 48deg, XT50 50deg ??

Does 2 degrees of rake either way really make a noticable difference in
A. weed shedding
and B. safer riding with less spinout

A. It is about perception people believe you need a 50 degree fin to shed think weed in some spots in Australia. It was shown not to be the case with the Delta XT which blasted around budgie without a problem. However the perception still persists so people have more confidence with a 50 degree fin and in sub planning conditions it works better the more rake you have.

B. In the case of the Delta XT and Delta XT-50 I believe the performance in regard to safer riding and less spinout will be the same as all that has really changed is the FWD tip was moved slightly forward to increase the rake all the rest that gave the Delta XT better performance has stayed the same.

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legless said..

sailquik said..

Stretchy said..
Original Delta 55deg, XT 48deg, XT50 50deg ??

Does 2 degrees of rake either way really make a noticable difference in
A. weed shedding
and B. safer riding with less spinout

A. It is about perception people believe you need a 50 degree fin to shed think weed in some spots in Australia. It was shown not to be the case with the Delta XT which blasted around budgie without a problem. However the perception still persists so people have more confidence with a 50 degree fin and in sub planning conditions it works better the more rake you have.

B. In the case of the Delta XT and Delta XT-50 I believe the performance in regard to safer riding and less spinout will be the same as all that has really changed is the FWD tip was moved slightly forward to increase the rake all the rest that gave the Delta XT better performance has stayed the same.

Yep. Thats about what I thought.

I have no problem blasting through weed on my 45deg 23cm Vector weed speed. As long as I keep my speed up in the gybes, all is good. However if I stop for some reason in a weedy spot, then this is when it's a real pain to get going and a 50-55deg fin is much better. This is the main driver for when I choose a more raked back fin.

When sailing in super shallow spots like Budgewoi lake, there is a very real risk of hitting things, sometimes weed bergs with a few sticks mixed in, once a pile of submerged newspapers and most memorably a 6" thick log. Every degree more of rake you have makes that moment of impact that little bit better, when I hit the log my 57 deg delta bounced me up into the air over the log, painful as it was, a much better outcome than the board stopping dead.

Have you seen the Fangy Fin thread?
A proven block splitter!

I haven't had a chance to try the 24 FF in the real shallow stuff but I did notice it had a firm feel when it you touched . I will be cautious until I've tested it on an upwind leg..

Xmas came early and I have got new toys to try out at the danish weedspot. Hopes that the 10 cm will work when the waterlevel is extremly low.

OOOOOOOH....
10cm delta! Will that start the ground effect debate again? I definitly want to try that!!!

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sailquik said..
OOOOOOOH....
10cm delta! Will that start the ground effect debate again? I definitly want to try that!!!

The ground effect debate starts at 50cm.




What you need to do is mount that 10cm fin in a deep single concave board.








Youtube hasn't got all that much to offer on shallow water physics. The background music is different !

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Ian K said..

What you need to do is mount that 10cm fin in a deep single concave board.

Excellent Ian, I think that's why heavily raked fins get better in shallower water, and a heavy weed base near the fin tip can do the same thing, even if the water is over waist deep.

And you're probably right about a concave bottom, there's no need for a "V" in flat water, but it probably doesn't need to be that deep?

You've got me thinking now, all my boards have about 3mm of V. But I'm mainly sailing flat water, perhaps a new flat water board is on the cards.

Or better still, now that you've entered ground effect world, build a ground effect foil. A small version of the foils currently sweeping deep water world. You want the foil to be small enough that it will not fully support the riders weight, at the design top speed, in deep water. But 2 or 3 cm off the bottom it'll be super efficient carrying all the weight in ground effect. It should be easier to ride than a regular deep water foil because it will have self- levelling attributes. You just need shallow water with no weed.

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Ian K said..

sailquik said..
OOOOOOOH....
10cm delta! Will that start the ground effect debate again? I definitly want to try that!!!

The ground effect debate starts at 50cm.




What you need to do is mount that 10cm fin in a deep single concave board.








Youtube hasn't got all that much to offer on shallow water physics. The background music is different !

See!
I was right!
Debate started again.

The WSSRC seems to have somewhat changed it's rules regarding water depth. 50cm does not always apply with smaller, narrow craft - like windsurfers and Kiteboards. Something about half the maximum beam of the hull or something.... whatever...... the Luderitz canal is definitly not 50cm deep all the way.

But to me, it seems there must also be a gain, as Decrepit says, to the efficiency of the fin when the tip is very close to the bottom. Close enough to interfere with the tip vortex. I believe I have experienced this - inadvertently - a 'few' times, where I seemed to have got a turbo boost just before I came to a sticky, painful stop.

But flirting with the shallows on the Sandy Point strip has always been my game.

Sometimes it does not pay off as I alluded to above, and as Mat found in this day: (Any excuse to see this again! )



And yes. I definitly think running a fin in weed must do some very nice things to make it more efficient.

Perhaps continue in a new thread Ian??

And just to come back to a more immediate relevance with respect to this thread, I wonder if the shallow water and weed effects can offset the inefficiency of the biplane fin set up Legless has?

Love the look of it Legless. Must be great fun to Gybe!

Tried the delta 18 today on the isonic 87 and 6,3. No weed so choppy. It did sail ok, I have never tried a real delta. I was underpowered so only got to 30 knots. As the wind picked up a little bit I switced to my Z-fins speed 23 and got 35 knots But that is also a completly different fin, both design and price.
Looks like I will get test the delta again in two or three days time.

I have used the "classic" Delta Slalom 19 (area: 317cm2) with a 7.0 and 102liter slalom board without any problems on flat water spots with a lot of weed, but I wonder how a 10cm Delta XT50 will do due to its small surface.. @Kasper, do you know how big surface area the 10cm XT50 has? I will come to Ringk?bing Fjord this winter, it could be interesting to test the classic Delta Slalom 19 against your 18 XT50..