Those who run Naish foils, have you tried shimming the rear stailiser and was it effective?
I'm particularily interested in results with the HA foils 
I have some 3D printed shims that I use and mostly use the numer 2 shim with the thicker end at the rear..
I doesn't make a huge difference but it is noticeable.. You can also use those square plastic bread bag ties..
Applying rear wing shim can exaggerate or lessen the force produced by the stabiliser wing. I find the best way to explain a foil setup is that we're essentially riding a unicycle. And the Stab is our training wheels. The more input we can get from our training wheels the easier it can be to balance up flight. But the big thing to remember is that the lifting force will still remain from the same location on the front wing. Adding extra down force by shimming your rear wing will make your rear wing want to ride more inclined in it AoA and thus increase lift, but also drag. It will often likely also increase the feeling of needing front foot pressure. Shimming the other way will do the opposite, suggesting the front wing will want to naturally ride in a more nose down pitch.
Key things to remember is that nothing is for free. If you shim up to get a more aggressive AoA, it will be at the cost of drag. If you shim down, it iwll be at the cost of lift and flight angle but potentially increase efficiency (lessor AoA).
Also the best way to describe whether it is positive or negative shimming is by comparing it to the stick angle differnce between the FW and RW. If the shim adds more of a differential to the angle difference then it is a positive shim, if it lessens the angle differential, then it is a negative shim. Your front wing is generally either neutral (0) or LE up AoA like (0.5 - 1). Your rear wing is generally the other way (LE down) at 1.5 - 2.5 degrees. SO anywhere between 2 and 3.5 degrees from stock.
Ride safe,
JB
I've not used, or felt any need to use any shims with any of the Naish foils I have - although I'm not really a techie or need to analyse performance, other than knowing when I've had a good session or not.
Having said that, I have been using the 280 stab and just got my 220 yesterday. Looking forward to getting on the water to see how it goes with all foils from my 914 and 1040, all the way up to the 2140.
The numbers and photos of the 2 stabs on paper are one thing, but when I compared the 280 and the 220 in the garage, there is quite a size difference.
Select to expand quotekersh said..
I've not used, or felt any need to use any shims with any of the Naish foils I have - although I'm not really a techie or need to analyse performance, other than knowing when I've had a good session or not.
Having said that, I have been using the 280 stab and just got my 220 yesterday. Looking forward to getting on the water to see how it goes with all foils from my 914 and 1040, all the way up to the 2140.
The numbers and photos of the 2 stabs on paper are one thing, but when I compared the 280 and the 220 in the garage, there is quite a size difference.
Like wise I don't feel any need to shim either.
re stab - the 220 is the go.
I use 220 for all my wings 1400,1240,1040,900 and 700.
recently I got another 220 and have chopped the wing tips off and that has made the smaller wings (1040 and down)a lot quicker through the water.
Select to expand quotesnides8 said..kersh said..
I've not used, or felt any need to use any shims with any of the Naish foils I have - although I'm not really a techie or need to analyse performance, other than knowing when I've had a good session or not.
Having said that, I have been using the 280 stab and just got my 220 yesterday. Looking forward to getting on the water to see how it goes with all foils from my 914 and 1040, all the way up to the 2140.
The numbers and photos of the 2 stabs on paper are one thing, but when I compared the 280 and the 220 in the garage, there is quite a size difference.
Like wise I don't feel any need to shim either.
re stab - the 220 is the go.
I use 220 for all my wings 1400,1240,1040,900 and 700.
recently I got another 220 and have chopped the wing tips off and that has made the smaller wings (1040 and down)a lot quicker through the water.
How do you find the 700, I'm 100% on the 900 in all conditions and just wondering if the 700 has much benefit.
Select to expand quoteairsail said..snides8 said..kersh said..
I've not used, or felt any need to use any shims with any of the Naish foils I have - although I'm not really a techie or need to analyse performance, other than knowing when I've had a good session or not.
Having said that, I have been using the 280 stab and just got my 220 yesterday. Looking forward to getting on the water to see how it goes with all foils from my 914 and 1040, all the way up to the 2140.
The numbers and photos of the 2 stabs on paper are one thing, but when I compared the 280 and the 220 in the garage, there is quite a size difference.
Like wise I don't feel any need to shim either.
re stab - the 220 is the go.
I use 220 for all my wings 1400,1240,1040,900 and 700.
recently I got another 220 and have chopped the wing tips off and that has made the smaller wings (1040 and down)a lot quicker through the water.
How do you find the 700, I'm 100% on the 900 in all conditions and just wondering if the 700 has much benefit.
I've only used the 700 once as I picked it up in January in Perth.
I'm now in Dampier,a place where the wind doesn't quite get the same punch as Perth.
From the initial try out, it was as expected another notch quicker and livelier.
Surprisingly not a lot harder to get going than the 900 which I love.
Both the 700 and the 900 are Mach 1's.
The biggest improvement in speed I have found came from trimming the wing tips off the 220 stab.
The 900 is my go to for 15knots.
As for the 700 I plan on using in winds above 18
Im around 76kg.
Thanks all :) I am looking to shim the trailing edge of the rear stailiser to create more front foot pressure (mast is already at the front of the box and I am still back foot heavy), it will be interesting to see how much I notice the drag.
On a side note, I tried the 280 stab from my 1400HA with my 1800HA. It felt good and seemed to loosen it up a bit, as well as giving more speed.
Select to expand quoteDavidJohn said..
I doesn't make a huge difference but it is noticeable.. You can also use those square plastic bread bag ties..
David, I'd be interested to know what difference you noticed in particular?
Select to expand quoteMilesH said..
Thanks all :) I am looking to shim the trailing edge of the rear stailiser to create more front foot pressure (mast is already at the front of the box and I am still back foot heavy), it will be interesting to see how much I notice the drag.
On a side note, I tried the 280 stab from my 1400HA with my 1800HA. It felt good and seemed to loosen it up a bit, as well as giving more speed.
What board are you riding having to slam to the front? I've got a 90l axis and also found naish foil (1240ha) works best almost slammed ip front. Taken me 9 months to figure that out....
Select to expand quoteQtwind said..MilesH said..
Thanks all :) I am looking to shim the trailing edge of the rear stailiser to create more front foot pressure (mast is already at the front of the box and I am still back foot heavy), it will be interesting to see how much I notice the drag.
On a side note, I tried the 280 stab from my 1400HA with my 1800HA. It felt good and seemed to loosen it up a bit, as well as giving more speed.
What board are you riding having to slam to the front? I've got a 90l axis and also found naish foil (1240ha) works best almost slammed ip front. Taken me 9 months to figure that out....
Naish board and Naish Foils
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Select to expand quotesnides8 said..kersh said..
I've not used, or felt any need to use any shims with any of the Naish foils I have - although I'm not really a techie or need to analyse performance, other than knowing when I've had a good session or not.
Having said that, I have been using the 280 stab and just got my 220 yesterday. Looking forward to getting on the water to see how it goes with all foils from my 914 and 1040, all the way up to the 2140.
The numbers and photos of the 2 stabs on paper are one thing, but when I compared the 280 and the 220 in the garage, there is quite a size difference.
Like wise I don't feel any need to shim either.
re stab - the 220 is the go.
I use 220 for all my wings 1400,1240,1040,900 and 700.
recently I got another 220 and have chopped the wing tips off and that has made the smaller wings (1040 and down)a lot quicker through the water.
I use the 220 on the 2140HA as well. Works perfectly.
Select to expand quotewinddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Select to expand quoteMilesH said..Qtwind said..MilesH said..
Thanks all :) I am looking to shim the trailing edge of the rear stailiser to create more front foot pressure (mast is already at the front of the box and I am still back foot heavy), it will be interesting to see how much I notice the drag.
On a side note, I tried the 280 stab from my 1400HA with my 1800HA. It felt good and seemed to loosen it up a bit, as well as giving more speed.
What board are you riding having to slam to the front? I've got a 90l axis and also found naish foil (1240ha) works best almost slammed ip front. Taken me 9 months to figure that out....
Naish board and Naish Foils
I'm an old bloke, natural footer with a few screws in my left hip and riding the 85L Carbon Ultra Hover. I had a hard time keeping weight on my front foot when gybing onto a swell ( nose would want to stay high ). Originally I had the mast close to the front of the box but moved it back around 30mm ( so now the 'HOV' in HOVER is showing ) and the board stays level throughout and I don't struggle to keep my weight forward.
In flat water I'll move the mast forward 15mm or so.
Select to expand quotewinddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
I'm now on all S27 gear and I was def able to push the pedal down on the old 80cm fuse. They really do need a 72 and perhaps another 80 back in the mix for the racers and folks feeling the need for speed. Otherwise, I love the 64 for everything else.
Select to expand quotesnides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Does chopping the stab make it more twitchy or just faster?
Select to expand quoteMilesH said..snides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Does chopping the stab make it more twitchy or just faster?
Yes a little more twitchy at the start ,but doesn't take long to get dialled in.
I went back to the standard 220 for a try out a few days ago and the drag increase is quite large.
Select to expand quotesnides8 said..MilesH said..snides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Does chopping the stab make it more twitchy or just faster?
Yes a little more twitchy at the start ,but doesn't take long to get dialled in.
I went back to the standard 220 for a try out a few days ago and the drag increase is quite large.
Thanks, I have a spare 280 stab and tempted to try it
Select to expand quotesnides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Those who have chopped their stab; do you need to seal the ends with epoxy or similar or is it not necessary?
Select to expand quoteMilesH said..snides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Those who have chopped their stab; do you need to seal the ends with epoxy or similar or is it not necessary?
I've not cut any of mine but I'm sure they are solid carbon and no foam core.. Just cut.. shape.. and sand.
Select to expand quoteDavidJohn said..MilesH said..snides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Those who have chopped their stab; do you need to seal the ends with epoxy or similar or is it not necessary?
I've not cut any of mine but I'm sure they are solid carbon and no foam core.. Just cut.. shape.. and sand.
Great thanks David. We are having big issues at the moment getting Naish stuff in the UK (I'm told due to the Naish buy out and stock delays to europe). I'm struggling to even get hold of a 220HA stabiliser hence chopping the 280 I already have.
I'm hoping to try the mach1 foils as well but there's non available in the uk at the moment.
Select to expand quoteMilesH said..DavidJohn said..MilesH said..snides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Those who have chopped their stab; do you need to seal the ends with epoxy or similar or is it not necessary?
I've not cut any of mine but I'm sure they are solid carbon and no foam core.. Just cut.. shape.. and sand.
Great thanks David. We are having big issues at the moment getting Naish stuff in the UK (I'm told due to the Naish buy out and stock delays to europe). I'm struggling to even get hold of a 220HA stabiliser hence chopping the 280 I already have.
I'm hoping to try the mach1 foils as well but there's non available in the uk at the moment.
Hi Miles. Hi Miles, how did the chop shop go? Could you send a photo? I'm thinking of doing a chop shop on my 220HA too.
Select to expand quoteKjeld said..MilesH said..DavidJohn said..MilesH said..snides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Those who have chopped their stab; do you need to seal the ends with epoxy or similar or is it not necessary?
I've not cut any of mine but I'm sure they are solid carbon and no foam core.. Just cut.. shape.. and sand.
Great thanks David. We are having big issues at the moment getting Naish stuff in the UK (I'm told due to the Naish buy out and stock delays to europe). I'm struggling to even get hold of a 220HA stabiliser hence chopping the 280 I already have.
I'm hoping to try the mach1 foils as well but there's non available in the uk at the moment.
Hi Miles. Hi Miles, how did the chop shop go? Could you send a photo? I'm thinking of doing a chop shop on my 220HA too.
Hi Kjeld. I chopped my 280HA to the same size width as the 220HA (which also removed the upswept tips). It made it faster and a bit more twitchy - which you get used to it quickly. No need to fill the ends either. I did have to shim it 1 degree to increase front foot pressure slightly (personal taste).
No pics sorrry but it looks just like the picture above.
Why do you want to chop your 220HA?
Select to expand quoteMilesH said..Kjeld said..MilesH said..DavidJohn said..MilesH said..snides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Those who have chopped their stab; do you need to seal the ends with epoxy or similar or is it not necessary?
I've not cut any of mine but I'm sure they are solid carbon and no foam core.. Just cut.. shape.. and sand.
Great thanks David. We are having big issues at the moment getting Naish stuff in the UK (I'm told due to the Naish buy out and stock delays to europe). I'm struggling to even get hold of a 220HA stabiliser hence chopping the 280 I already have.
I'm hoping to try the mach1 foils as well but there's non available in the uk at the moment.
Hi Miles. Hi Miles, how did the chop shop go? Could you send a photo? I'm thinking of doing a chop shop on my 220HA too.
Hi Kjeld. I chopped my 280HA to the same size width as the 220HA (which also removed the upswept tips). It made it faster and a bit more twitchy - which you get used to it quickly. No need to fill the ends either. I did have to shim it 1 degree to increase front foot pressure slightly (personal taste).
No pics sorrry but it looks just like the picture above.
Why do you want to chop your 220HA?
Hi Miles, thanks for the information. I want to chop my 220HA, because im getting into racing and I want to reduce the drag for extra speed.
Did you round of the edges or did you also leave it straight cut?
Select to expand quoteKjeld said..MilesH said..Kjeld said..MilesH said..DavidJohn said..MilesH said..snides8 said..winddoc said..
Hi snides8
Interesting to note your comment on chopping the wings off the 220 stab. Can you post a picture and explain how to chop it off and how to get a smooth finish at the ends.
I use the 914 with the long 80cm. fuselage and find the extra pitch stability amazing for riding.
unfortunately, Naish is not offering the 80cm. fuselage with the S 27 mast. I think the slightly longer fuse
will be an amazing match for the 900 and 700 foils.
Yeah I just cut them off parallel to the fuse just on the upturn of the tips.
just had finished with wet and dry.
I saw a chap had cut his on another thread and had an increase in speed as well.
I have the s27 fuse and mast so using a 64 fuse.
Those who have chopped their stab; do you need to seal the ends with epoxy or similar or is it not necessary?
I've not cut any of mine but I'm sure they are solid carbon and no foam core.. Just cut.. shape.. and sand.
Great thanks David. We are having big issues at the moment getting Naish stuff in the UK (I'm told due to the Naish buy out and stock delays to europe). I'm struggling to even get hold of a 220HA stabiliser hence chopping the 280 I already have.
I'm hoping to try the mach1 foils as well but there's non available in the uk at the moment.
Hi Miles. Hi Miles, how did the chop shop go? Could you send a photo? I'm thinking of doing a chop shop on my 220HA too.
Hi Kjeld. I chopped my 280HA to the same size width as the 220HA (which also removed the upswept tips). It made it faster and a bit more twitchy - which you get used to it quickly. No need to fill the ends either. I did have to shim it 1 degree to increase front foot pressure slightly (personal taste).
No pics sorrry but it looks just like the picture above.
Why do you want to chop your 220HA?
Hi Miles, thanks for the information. I want to chop my 220HA, because im getting into racing and I want to reduce the drag for extra speed.
Did you round of the edges or did you also leave it straight cut?
I just cut them straight like the pic above.
Let me know how you get on and what it feels like compared to the standard 220HA
Select to expand quoteKjeld said..
Hi Miles, thanks for the information. I want to chop my 220HA, because im getting into racing and I want to reduce the drag for extra speed.
Did you round of the edges or did you also leave it straight cut?
Initial cut parallel to the fuselage. The put a nice looking radius curve on the front corners, and round the rear corners for some safety. Then you should taper the cut material when looking from the front-on view. Round the tapers to fair into the foil top and bottom and ensure the leading edge of the tips are thin and fair. If you don't know what the shape should look like then it might help to aim fast running hose water at the tips and observe the ease of water flow.
On my HA280 I cut the winglets off completely and gained some speed, but you also lose a lot of yaw stability. Being yaw loose is good for flat turning at low speeds, but lots of yaw stability is best for high speed. eg. Look at all the fast kitefoil stabilisers. So you are probably better off starting with the HA220 and cutting only half of the winglets off, to retain some up-turn in the tips, to retain some yaw stability.
When you lose yaw stability you also increase the risk of a mast ventilation. Which is mostly a problem going upwind at speed in chop with the C100 mast. But without winglets, I could also ventilate the mast going downwind with foil flat and near the surface. The mast just lets go the leeward side and you get an odd feeling until it re-grabs.
To go faster, try using the stab position one fwd of full aft. I found the most rear mounted position was slower. Although more pitch stable and more pitch control, I presume it generated more drag.
Also to go faster, you can consider sanding your rear foils to be thinner. It makes a big difference. But it's easy to ruin the shape so be cautious if you don't trust your eye or sanding fairing skills. I did my best speeds with a HA280 that was substantially cut down on the tips and also about 0.5mm thinner. Really good pitch control so I could bring the 914 close to the surface.
If you have the 914 front foil, you can cut (sand) just 10mm off each tip to remove some of the negative twist, and it'll go a little faster too, at the cost of a little lift at take-off speeds.
I'm interested in a thin stab for naish to decrease drag for extra glide riding chop flagged out. 100kg rider looking for greatest efficiency. I was investigating a custom rear wing or a 3d print to get an axis foil to suit since I think they do this area really well?
I have a 280 chopped stab so might first try thinning it as Emmett said want sure if you need to leave the coating on the foils for efficiency? I have a clear coat I can finish it with after thinning. Is 0.5mm enough? The modern ones from axis seem mighty thin compared to the 220ha stab
Select to expand quotewhitewind said..
I'm interested in a thin stab for naish to decrease drag for extra glide riding chop flagged out. 100kg rider looking for greatest efficiency. I was investigating a custom rear wing or a 3d print to get an axis foil to suit since I think they do this area really well?
I have a 280 chopped stab so might first try thinning it as Emmett said want sure if you need to leave the coating on the foils for efficiency? I have a clear coat I can finish it with after thinning. Is 0.5mm enough? The modern ones from axis seem mighty thin compared to the 220ha stab
To mount a different brand rear foil on a Naish fuselage, you might want to start with a brand that has a flat mounting surface, as on the fuselage tail. Then fill and re-drill the mounting holes. Bolt it on, go foiling, and see if it needs angle shimming.
Assuming you don't completely sand away a structural layer, the surface finish material only matters in hardness and consistency, so you can sand the desired pattern. eg. 800 grit at +- 45. Polyurethane or Durapox paint are real nice to have. But the Naish injected chopped up carbon epoxy stuff (in my S25 HA280) also sands to leave a very nice even surface.
btw: You can use the factory clear paint as top layer for shape fairing. The foil won't look glossy any more, but possibly huge perf gains and less noise after you fix any defects in the clear coat.
As soon as you cut your tips off you'll see how thick the stronger surface material is. And if there is a softer core material. To thin the foil out, be sure to use the correct fairing technique. If you sand a flat spot on the foil then you might be very disappointed when you use it.
Just to offer a bit of information regarding speeds with the Naish 914 front wing and changing out rear stabilisers. I competed in the recent Burrum Wind Fest in Queensland, The wind fest is a GPS monitored speed event that has been running for 15 + years. The wind during the 4 official days of competition was a consistent 20 - 25 knots. To make the most of the speed potential my smallest hand wing was a 5 metre.
For all of the rear stabilisers, I had measured the relative angles to the front wing and had setup a documented list of packing to achieve as close to the same angle on each one. My base setup was the chopped 280 with1 piece of credit card made into a washer under the front bolt.
1. Initially I used a custom 17.5mm wingspan x 6mm thickness rear wing and achieved a speed range from 14.2 knots to 13.0 knots.
2. Moved to a cut down 280 Naish Tail, speeds ranged from 16.3 to 12.6 knots.
3. Changed to a Go Foil 14.5 rear stabiliser while achieving speeds at 13.8 to 13.5 knots.
All in all, I found that the Naish setup was the most stable. I found that the other rear stabilisers needed me to actively fly the foil to maintain speed and control. As the speed increased this became increasingly difficult to maintain speed and focus on what I was trying to achieve. Now by stable I mean that I could maintain the same foot position and body attitude, and focus completely on going fast, any of you that have tried the cross wind run as fast as possible and then bear away further downwind will understand what I mean, complete focus is required.
The only reason I am offering this is that the whole competition was GPS monitored, so apples were apples.
At the competition, the fastest winger was on an AXIS 799, the 2nd fastest was on a North Sonar 750. speeds were 22 and a bit and 21 knot respectively. Compared to the wind foilers on 450 and 500 front foils we were slow by up to 10 knots. FYI, I was 3rd.
So, I feel the size does matter, smaller size.
Just to clarify, I would class myself as a beginner/intermediate winger.
I probably should say that the speeds I mentioned above where for 500 metres and Nautical mile (1.8kms). My best 2 secs speed was 18.9 knots.
Gary
