Re: Cam program and post needed for a cnc propeller carving lathe

2a. Cam program and post needed for a cnc propellor carving lathe
Posted by: "Larry" reiss_machinist@... reiss_machinist
Date: Thu Jan 29, 2009 10:27 am ((PST))

I am interested in building a cnc propellor carving lathe to create
wooden wind turbine blades, one blade at a time. The proposed lathe
would be run with Mach 3 and 2 axis control having a servo motor
drive on the headstock spindel and one on the cross slide axis. There
would be gearing and a lead screw to slave the Z axis from the spindel
at the rate of .125" per revolution.The cutting tool would be a 10"
dia. carbide table saw blade that would move in and out on the cross
slide X axis as the spindel rotated continuously.
I have use of a program that will create an STL. file of the
blade.But I need to learn of a cam program that will let me define the
axis of rotation and has a post processor for a machine of this
configuration.
Thank You, Larry Reiss Omaha, Nebraska

Hi Larry;

[Is there a reason these have to be made in wood? Is this a replication project, or are they supposed to be functional? If you're creating these for a museum or something I suppose authenticity counts, but for functionality I'd think you'd want these to be made in a high-tech composite material that isn't going to self-destruct in a high wind. No problem with mastering them in wood, I suppose, but I wouldn't want to be anywhere near your home-made wooden turbine when the prairie winds really pick up...

That said, this is a pretty unusual machine you describe above. Saw blades aren't generally used this way - I'd think you'd want something more like a router bit to do the cutting. A lathe spins a lot faster than you'd want it to for this; a rotary table would be more to the point. And there's no need for gearing and lead-screw slaving in the modern CNC era; the computer-controlled stepper or servo motors do all that for you in a more controllable and flexible manner. I'm pretty sure you won't find any posts for a machine like this, but compared to building this beast, writing a post-processor for it should be a piece of cake...]

Andrew Werby
www.computersculpture.com