Thrusters - Why way more common in performance surfing

Chat about stuff that doesn't fall into the other categories here.
Ruaraidh_K257
Posts: 293
Joined: Mon Jan 07, 2019 11:49 am
Has liked: 22 times
Been liked: 109 times

Re: Thrusters - Why way more common in performance surfing

Post by Ruaraidh_K257 »

I wondered how long it would be before you started talking about toe in Bouke :lol:
17, Scottish wavesailor
User avatar
Bouke/Witchcraft
Posts: 198
Joined: Thu Nov 08, 2018 9:32 pm
Location: Fuerte
Has liked: 3 times
Been liked: 102 times
Contact:

Re: Thrusters - Why way more common in performance surfing

Post by Bouke/Witchcraft »

Ruaraidh_K257 wrote: Sat Apr 10, 2021 8:37 am I wondered how long it would be before you started talking about toe in Bouke :lol:
Yes, sorry but that is what the question of the OP is about. Still, after all those years. Anyone can still be happy with their gear, you will not notice much in mushy conditions at lower speeds. But one of these guys with this Quatro is a local and a decent wave rider and was about to sell it as he was unhappy up to a point it was visible from the beach he was held back compared to his mates with Witchcraft boards. Also after the change, it was visible he was riding much better, more speed, tighter turns and he was getting aerials again. It is a bit of a weird shape with 96L pumped into the sizes of an 87L but other wise the shape is fine and should ride better than it did.
Image
Image
Image
WhatsApp Image 2020-08-08 at 15.00.49.jpeg
https://witchcraft.nu/. Boards, sails, masts, fins.
DavidA
Posts: 175
Joined: Sun Nov 25, 2018 9:59 pm
Location: Bigbury
Been liked: 29 times

Re: Thrusters - Why way more common in performance surfing

Post by DavidA »

There is also a lot on the K4 fins website about thrusters and toe-in. I must admit on my non witchcraft boards have used the K4 asymmetric Ezzy thruster fins to good effect. With these fins you get to choose the toe in angle according to how much the fin box has already and the guidance from the K4 website.
Dkarl
Posts: 17
Joined: Mon May 06, 2019 1:29 pm

Re: Thrusters - Why way more common in performance surfing

Post by Dkarl »

If I would sail the Fuerte spots as home spots I would buy a Witchcraft for sure.
User avatar
Bouke/Witchcraft
Posts: 198
Joined: Thu Nov 08, 2018 9:32 pm
Location: Fuerte
Has liked: 3 times
Been liked: 102 times
Contact:

Re: Thrusters - Why way more common in performance surfing

Post by Bouke/Witchcraft »

Dkarl wrote: Mon Apr 12, 2021 10:16 pm If I would sail the Fuerte spots as home spots I would buy a Witchcraft for sure.
Funny, 98% of our boards sail elsewhere.

Here is a bit more info on fins and turning: https://witchcraft.nu/windsurfing-scien ... -is-drive/
https://witchcraft.nu/. Boards, sails, masts, fins.
Ola H.
Posts: 91
Joined: Fri Nov 09, 2018 2:39 pm
Has liked: 21 times
Been liked: 47 times

Re: Thrusters - Why way more common in performance surfing

Post by Ola H. »

Like Bouke says, the question is kind of the wrong one. The real question is why most windsurfer (or the designers) insist on such small front fins. In any case you can not really make sense of any comparison to surfing without considering the different styles of front fins.

Assuming the small fronts windsurfers tend to use, the difference between quad and thruster becomes really accentuated since the thruster setup will need a rather large center fin while the quad can stay with a rather small center fin. This makes the quad ride softer because fo a bit more slip and some center of effort effects and overall it makes in particular the tp turn a bit more forgiving because you can have some slip without total grip loss. In addition, the relatively large center fin needed adds some leverage and makes turn entry slower, so you get quicker reactions out of your quad set. This is not the preferred feel by all, but by relatively many. For punters, these differences tends to be even bigger since they usually will need more rear fin(s) because the fronts are rarely upsized (and more or less cant be without making the whole setup draggy, because of the reasons Bouke presented)

With larger surf style fronts the quad/thruster difference becomes much smaller since you are not really changing the rear fin size all that much, as least not. It's more like in surfing and in most cases the differences are not deal breaking. That said, for me that exclusively use surf style fronts with appropriate toe in there is a lot to gain by going between quad and thruster on the same board (staying with the same fronts). Thruster mode provides a little bit more projection in the bottom turn and a quicker engagement meaning I can get drive faster and easier without needing too much board angulation. Conversely, quads makes the board stay calmer on its rail if it is fast and rough and you don't want that drive. Also for some smaller waves in particular in windy conditions I like the quad feel. So by being able to go between, I get a bit more out of the same board.

I reckon that if more windsurfers were on "proper" front fins, more people would also be on thruster setup because it would be forgiving enough and a little easier to tune and sail. Switching to quads would be a good way to tune the same board for wilder conditions.
Max
Posts: 91
Joined: Thu Nov 08, 2018 5:39 pm
Has liked: 25 times
Been liked: 35 times

Re: Thrusters - Why way more common in performance surfing

Post by Max »

i'm jumping in here i recently won a windsurfing .tv competition to win a 2021 Severne S1 5.0m sail very nice and pricey but i sail simmers and have last years so really couldn't use it it would probably have meant a mast change for that sail etc etc so anyway i part ex'd it against a Severne Dyno 95l 2018 model they had

i've since sailed this and in it's thruster mode and it feels so draggy when trying to go upwind once i cant the board onto its rail to make some headway upwind its seems to stall ? it has a 12.5cm side fin x 2 and a 22cm central fin i could probably work out the toe in on the board and see if that is wrong for the fins supplied


any ideas as it feels so slow and draggy to my other tri fin option boards
Ruaraidh_K257 wrote: Sat Apr 10, 2021 8:37 am I wondered how long it would be before you started talking about toe in Bouke :lol:
i can believe the hype as i can feel the difference on this board fins make or break a board imo
Ola H.
Posts: 91
Joined: Fri Nov 09, 2018 2:39 pm
Has liked: 21 times
Been liked: 47 times

Re: Thrusters - Why way more common in performance surfing

Post by Ola H. »

Did you try it in single mode?
Max
Posts: 91
Joined: Thu Nov 08, 2018 5:39 pm
Has liked: 25 times
Been liked: 35 times

Re: Thrusters - Why way more common in performance surfing

Post by Max »

Ola H. wrote: Tue Apr 13, 2021 7:29 pm Did you try it in single mode?
no not yet but i was hoping to use it as a wave board for onshore stuff i will give it a try and see how it feels as a single but would probably shift it on if i can't sort it

ok done some more digging and measuring so according to the K4 fin toe in calculator the board has 0 deg toe in on the box positions it being 278mm apart both top and bottom of the internal box to box measurement

which i think is why it feels draggy

K4 fins then recommend using a Ezzy + 3 deg toe in these are EZZY ASYMMETRIC FINS i would go for the 10cm length and drop from the 12.5cm length

Bouke Ola any suggestions or indeed any fin choices i should look at Bouke do you sell your fins as standalone items ?
Ruaraidh_K257
Posts: 293
Joined: Mon Jan 07, 2019 11:49 am
Has liked: 22 times
Been liked: 109 times

Re: Thrusters - Why way more common in performance surfing

Post by Ruaraidh_K257 »

Max wrote: Tue Apr 13, 2021 5:54 pm i'm jumping in here i recently won a windsurfing .tv competition to win a 2021 Severne S1 5.0m sail very nice and pricey but i sail simmers and have last years so really couldn't use it it would probably have meant a mast change for that sail etc etc so anyway i part ex'd it against a Severne Dyno 95l 2018 model they had

i've since sailed this and in it's thruster mode and it feels so draggy when trying to go upwind once i cant the board onto its rail to make some headway upwind its seems to stall ? it has a 12.5cm side fin x 2 and a 22cm central fin i could probably work out the toe in on the board and see if that is wrong for the fins supplied


any ideas as it feels so slow and draggy to my other tri fin option boards
Ruaraidh_K257 wrote: Sat Apr 10, 2021 8:37 am I wondered how long it would be before you started talking about toe in Bouke :lol:
i can believe the hype as i can feel the difference on this board fins make or break a board imo

Was just being cheeky, lately I’ve been beginning to think Bouke and Ola are onto something... funny that as they’re professionals 🤣

About to get a bunch of K4 assyms to try. Will report back to this thread! :D
17, Scottish wavesailor
Post Reply