Author Topic: Diy foil nz  (Read 5775 times)

surfcowboy

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Re: Diy foil nz
« Reply #60 on: September 25, 2018, 07:04:26 PM »
Kiwi thanks and youíre totally right about the plywood for prototypes, keep em fast and weight probably isnít that big of a deal. Others have said so on here.

Thanks for the offer of help. Yes, Iím in Fusion360. Iíll PM you when I get something I like together. Iím trying to make myself learn a bit and so Iíll do a bit of homework. Cleaning up my garage, wonder if Iíll find space for a CNC lol.

kiwi

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Re: Diy foil nz
« Reply #61 on: September 26, 2018, 05:19:26 PM »
As far as mast twist and flex.  6 layers of 3K carbon twill layed 45 dgrees and 90 degrees would fix it.  Vacuum bagging helps but is not necessary.

Yeah I'm probably going to have to do something like this for the new wing with all the torque acting for the size of the wing. Or just build a new one lol

I would done something like this but we only have carbon unis at home and don't have any cloth. Two of the carbon uni layers are laid at an angle that runs from the top back corner to the bottom front corner and opposite for the other layer so hopefully that does something similar.

kiwi

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Re: Diy foil nz
« Reply #62 on: September 28, 2018, 02:50:58 AM »
Glued in the glass plate for the bolts to be countersunk into on the wing and glued a plate to the fuz to allow bolt mounting further outboard on the wings.
Didn't have enough time but will reinforce that new fuz wing mount with a whole lot of carbon and glass.
Trailing edge is now glassed and I sanded that up today and put a coat of resin over the whole thing as a temporary waterproofing for this weekends use.
Should be fine for testing but needs a whole filler coat and sand to make it fair.
« Last Edit: September 28, 2018, 02:52:49 AM by kiwi »

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Re: Diy foil nz
« Reply #63 on: October 10, 2018, 09:14:56 PM »
did you end up trying the new wing? looks mint! whats the span? and did you vacuum the glass plate for tapping into, im going to do a similar sort of thing on my one but i thought maybe resin rich would be better for tapping.

got my new super downwind flyer ready for glassing, 1100mm span

kiwi

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Re: Diy foil nz
« Reply #64 on: October 10, 2018, 11:28:04 PM »
did you end up trying the new wing? looks mint! whats the span? and did you vacuum the glass plate for tapping into, im going to do a similar sort of thing on my one but i thought maybe resin rich would be better for tapping.

got my new super downwind flyer ready for glassing, 1100mm span

Yeah I had a go on the new one, didn't do so good in the surf but I'm gonna give it another go because it was shin height lol. Towing behind the boat it went sweet. Started lifting at 5 knots and flew best around 10. I think im gonna play around with stabilisers because Im not sure about this one.

Its 900mm span with 250mm chord. That wing looks mean, keen to see how slow it flies. Whats the chord on it?

The glass is plate dad had laying around from a job a few years ago, Im pretty sure its vacuumed but it works sweet for threading, I use helicoils instead of just straight threads.

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Re: Diy foil nz
« Reply #65 on: October 11, 2018, 05:30:57 PM »
looks good in the video! stabilizers is a tricky one, i gave up and took a mold off a gofoil maliko tail cause they have a nice twist to them and it made a huge difference in every aspect. pitch stability, turning, pumping everything became much easier and smoother.

the chord on this wing is about 260mm. i like them slightly higher aspect ratio with a fuller, rounder leading edge to improve the low speed/ high AoA flying which high aspect ratio wings dont usually like, seems to be working extremely well on my current foil although the heavily swept wing may also have something to do with this

kiwi

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Re: Diy foil nz
« Reply #66 on: October 27, 2018, 11:54:47 AM »
A few mods over the past couple weeks.
I routed down the wing where the fuz attaches so it doesn't protrude and the fuz is now recessed into and sits nice and flush, way less drag.
Also layed some reinforcement around the mast attachment on the fuz as I can still feel the new wing trying to tear itself free when turning, this should make it super solid and stable.

Next plans are to bog everything up and get a coat of durapox on it because epoxy isn't the best when it comes to drag.
« Last Edit: October 27, 2018, 11:57:17 AM by kiwi »

surfcowboy

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Re: Diy foil nz
« Reply #67 on: October 27, 2018, 08:47:05 PM »
This is looking great.

I finally got mine back in the bag and fixed the front of my fuse.

I like your wider wing mount. Mine is top mounted too now but only a couple of inches wide. Iím concerned about the stress on my foam and glass wing. Going to beef it up but Iíve got about the same mount size as the Armstrong wings so hoping itís solid enough. Probably need to build a plywood wing next actually.

Container, how did you get the bend in yours, did you put relief cuts in the bottom and then fill them? Also, how thick are yíallís wings?

Final question. Iím looking for stainless threaded inserts. Should I use helicoils instead? Which do you think is stronger? I just figured the screw in threaded inserts were the best I could do for mounting in wood.

kiwi

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Re: Diy foil nz
« Reply #68 on: October 28, 2018, 11:57:21 AM »
This is looking great.

I finally got mine back in the bag and fixed the front of my fuse.

I like your wider wing mount. Mine is top mounted too now but only a couple of inches wide. Iím concerned about the stress on my foam and glass wing. Going to beef it up but Iíve got about the same mount size as the Armstrong wings so hoping itís solid enough. Probably need to build a plywood wing next actually.

Container, how did you get the bend in yours, did you put relief cuts in the bottom and then fill them? Also, how thick are yíallís wings?

Final question. Iím looking for stainless threaded inserts. Should I use helicoils instead? Which do you think is stronger? I just figured the screw in threaded inserts were the best I could do for mounting in wood.

This new wing is a NACA 4416 so at 250mm chord thats 40mm thick.
If you are threading into solid glass or carbon I would go with helicoils but it sounds like threaded inserts might be better for wood.

Container might have laminated several layers of a smaller thickness across his mold but I'm not totally sure, relief cuts don't really make any sense for strength.

surfcowboy

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Re: Diy foil nz
« Reply #69 on: October 28, 2018, 11:04:03 PM »
After I posted I thought of laminating a few thinner layers. Hit send too soon.

Those donít look 40mm (1.5Ē for US) thick in the pics. Thatís thicker than I thought from looking at it.

Yes, I have a wood core in my fuse so the inserts will be seated (epoxied into) wood. After pulling it out of the bag tonight Iím thinking of adding a slightly bigger plate like you have under the fuse. I feel like I have the fuse sorted now but Iím concerned that I could break my wing if I donít reinforce it due to the lateral forces if the bolts are only 30-40mm apart. Even 10-15mm on each side would give way better leverage.

kiwi

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Re: Diy foil nz
« Reply #70 on: October 29, 2018, 01:29:14 AM »
After I posted I thought of laminating a few thinner layers. Hit send too soon.

Those donít look 40mm (1.5Ē for US) thick in the pics. Thatís thicker than I thought from looking at it.

Yes, I have a wood core in my fuse so the inserts will be seated (epoxied into) wood. After pulling it out of the bag tonight Iím thinking of adding a slightly bigger plate like you have under the fuse. I feel like I have the fuse sorted now but Iím concerned that I could break my wing if I donít reinforce it due to the lateral forces if the bolts are only 30-40mm apart. Even 10-15mm on each side would give way better leverage.

Yeah I've found that getting the connection between the front wing and your feet as stiff as possible is very handy when it comes to turning or even controlling it, the original fuz wing connection I had was fine for my little wing but the bit one yanks a bit harder on the mast and you can definitely feel it. Can you upload some picutres of your fuz to wing connection I need to get my head round it.

Yeah my wing is definitely 40mm at it's thickest point, I am starting to wonder about using fusion to model because it seems like the shape tapers off very quickly and becomes thinner much quicker than youd think, from looking at other foil brands they don't tend to do this. Maybe it's just the wing outline causing it or maybe designers using multiple stations with profiles that get thicker further down the wing but I'll do some more research into it first.


SUPeter

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Re: Diy foil nz
« Reply #71 on: October 29, 2018, 06:01:11 AM »
I have often wondered about either using the same wing profile from wing root to wing tip which is what I currently use(NACA 4416/4417) or changing the wing profiles from root to tip.  Have not yet heard of anyone using different wing profiles.  My wing tips seem plenty "thick".  Just curious?

surfcowboy

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Re: Diy foil nz
« Reply #72 on: October 29, 2018, 08:19:01 PM »
I could see Fusion introducing some weirdness but I never thought about before.

Iíll update my build thread soon. Posting pics from an iPad is a hassle and I only use this at night (I get plenty of computer time during the day lol)

My current plan is to just see if I can get a foil to fly. If so, I already have my next design worked out. You know how that goes. The second one of everything is better. Haha.

kiwi

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Re: Diy foil nz
« Reply #73 on: November 05, 2018, 09:26:51 PM »
Got quite a bit done since last post.
I made a new stab, this one has a bit more area just interested to see how that affects things.
Coated everything in durepox and started sanding today but its still a tad gummy. (the lighter colour is what it looks like sanded)
Also ive got a 4'7" prone board hacked up from another board going on in the background.
« Last Edit: November 05, 2018, 09:29:36 PM by kiwi »