Lakota Blades

[wdyasq]

Some time back a friend took pictures of an traced as best he could a Lakota blade.  This week, with the internet down where I am, I took time to model them.  THe airfoil starts about 6" out from the center and the diameter is 7'.  

I will offer this model in several 3D file formats for those who may care to cut them.  Please request the format you desire.  If RHINO can output in that format I shall post it.

Answers to questions.

1. No, I am not offering a G-Code format
   
2. No, I am not going to convert it to a format I do not have a converter for.
   
3. No, I will not resize it.
   
4. No, I do not know the tip-speed ratio.  IMO "Tip-speed ratios" are BS.
   
5. No, I do not plan on making an enlargement or smaller model.
   
6. No, I have no idea of the power of the Lakota mill.
   
   

Ron

[rotornuts]

Ron, I might be willing to take a kick at the can to write a program for that. I don't think it would be much help to anyone though as they would likely have to edit the crap out of it to get it to run on thier machine. I'm doing my CNC training at the moment so I'd write the program for a modern three axis Mazak milling machine that likely doesn't have the X axis travel to do that in one piece. Auto tooling and programmed feeds and speeds etc. so a basic machine would need alot of stuff edited out and other stuff added to make it run.

I'll check on monday but I think the school has the software to generate the program based on the 3-D rendering. I'll have to check the format.

That blade may well be over my head but I don't know yet as we're still working with lathes.

Nice job,

Mike

[Jerry]

One thing I've noticed about this blade that I would probobly change is a slight negative pitch at the tip.

I'm sure there must be some science for this and a reason for it?

I think it is a fairly high TSR blade but I don't know what the TSR # is?

2 days ago I was seeing around 180 amps from the lakota in some 50 mph gusts.

I also saw 60 amps in a 20 mph wind test. I'm using a set on a motor conversion that makes 2025 watts at 28 mph.

They are awsome blades. They startup a littel late compaired to my 4ft plastic blades but they can make a bunch of power.

Good luck with your copys.

                              JK TAS Jerry

[richhagen]

Nice looking rendering Ron. I don't think I can use it yet, but I could probably change a .DFX file into G-code, although it would take a boatload of editing for me to get the offsets right.  As you know I've been working on my own designs, and software to generate the machine - G-codes I need, but with work and all getting in the way, My progress has been painfully slow.  Rich

[RP]

Jerry, is it possible the negative pitch turns positive when the blade gets bent back in the wind?  Looking at the profile this seems possible.  It may only be negative when sitting static.

[Nando]

Ron:

If you have a DXF file format, I would like to have the data.

My address is in the profile.

Thanks

Nando

[rotornuts]

.DXF works for me as well. I'll use MasterCAM to generate the g-code for mill.

Mike

[Jerry]

I've watched these blades in 50 mph winds and they don't bend or flex back, very rigid.

                            JK TAS Jerry