Golf ball mod

Arthur suggested slope flyers that rough up thier wings to get more lift,well i was thinking if i set my blades over a pipe and progressivly drill say 2mm dimples on my drill press in a organised fashion over the length of the blades would this act like a golf ball does and create more lift,i think the dimples make the air go over the ball in such a fashion that it sucks its self upwards and along? if this was the case would i do it on the top and on the bottom or would this nulify the effect?.if this were to create more lift with the same blade speed youd think we could fly at a lower throttle setting and get longer flights?.

I'd bet you would get longer flight times but only if you put the dimples on the top of the airfoil. If you put in just enough, you might be able to save a couple grams?, anyway don't put in so many that the blade weakens and bends. (that would suck) (-:

Thanks baszer yeah i would only want to drill deep enough to create the shape ,maybe 1mm would be sufficient,if i do ill look at a golf ball to see how far apart the dimples are spaced(some dude must have spent millions trying to figure that one out),i was thinking of making a template to save time rather than marking out all the holes individually maybee from thin aluminium sheet that woul roll over the blade .

If it's stock, you might be able to melt the pattern into the blade and then sand the blade with rough sand paper to even improve on that!
Hey cool, I'm a member!

[This message has been edited by baszerkawits (edited 12-06-2000).]

an excellent place to find out if the dimples will work is from a company called DJ Aerotech. they make hand launch gliders and their designers know SO MUCH. i'm not sure of the adress but it will definitely be worth your while to check out.

[pitts_s1a]

The dimples act as a sort of turbulator, similar to the one already incorporated into the stock blade.

The original purpose of the dimples are to reduce drag, which could help in this case, if you can reduce the drag on the upper portion of the blade, the flow will accelerate, and the lift differential will increase. Sounds good to me.

I think that the dimples should have a rounded profile, a common drill bit has a conical profile. Maybe you could get a grinding stone with a rounded tip and try that instead, just chuck it in the press.

1mm sounds like a fair depth to start with, you can increase it if the results are marginal.

Will, are you planning to keep the original turbulator also, or will you remove it?

Phil.

I was thinking about that and cant really come to any conclusion.i do have a spare set of blades to try this out on but the trouble with the turbulator is that it is not removable and replacable cause then i could try with and without ,i can try first and then remove but im stuck with the latter and it would be a shame to go that far with the dimples and then stop there. Do any of the aftermarket blades still have the turbulator strip?.I have a perfect dremel conical bit that should do the trick.

I'm sure there are people using Roberts blade that would be happy to send the stock blades to you. Just to see how this turns out. I will send you mine, but they are cut, not sure if thats ok (I tried them one time, did not like them!)

what a man! thanks J dont forget its all in the name of piccolo science,i will start working out a way to dimpilise it in an orderly fashion ,although using the conical grinding stone might make it harder to center it on the mark everytime ,i think it hsa to be orderly as not to create to much confusion on the blades and in my head .

Hello Will, as far as I recall the glider and rubber boys had a cotton turbulator fairly close to the leading edge and lightly roughened the upper surface. There was a lot of talk about Reynolds numbers etc. Did you get the food mixer back together? Whenever I am watching Formula One motor racing I often wonder if the've ever tried a matt finish on the top of the wings and even perhaps the upper surfaces of the car. Mind you they've got wind tunnels and spend millions.