Duplicator

[SparWeb]

A friend of mine (Bill) was cleaning out his shop, and decided to give me his duplicator, since he knows about my wind turbine hobby addiction.
It's incomplete, and what I have needs some tuning up, but the motor's good and it's really given me a lot of ideas.

Basically, one of these: http://www.terrco.com/woodcarvers/kstar.php





There are 2 cutter heads - one on each side of the motor, 10 inches apart.  another 10 inches to one side of the cutters is a "stylus".  When you touch the stylus to the template part, the cutters can cut the same shape, making copies of the template part.

Does anyone think this might be a great idea for making WT blades??!

[SparWeb]

Hmmmm.
The blades I made had a 10" chord - sloped at an angle so that the projected chord is only 8.5". 
This could easily cut copies of my spare 10' blade.

I need to make a special bed to fit these blades.  Even the "60 inch" Terrco frame can't hold a full 60 inch part.

The product data says the spindles counter-rotate - but that doesn't make sense.  Where the hell do you get left-hand cutters?

[SparWeb]

Aw jeez.  You get left-hand cutters from K-star, of course!

[SparWeb]

I gave it a test run tonight.

The results in the pictures speak for themselves.  I will need to change something to improve the stiffness.

The axle is the weak link.  Those set-screws have to go.  They do not positively lock the wheels to the axle.  I think I can make a big improvement there.  Several possibilities are circling around my head.  Looking at the large tube on the carriage, there isn't a strong need for the ball bearings in the ends, and there's a very big bore through that tube that's not being used.  I think I could replace those with brass bushings and get rotation just as smooth.  The ID of the brass bushing could then go from 0.75" up to 1.5 inches, so I would gain a lot of room to put in a very rigid hub attachment from wheel to axle.

The cables work fairly well to keep the wheels synchronized, so I won't abandon that design feature just yet.

Things like the balance weights and the belt cover are just little jobs to do - easily dealt with.

[SparWeb]

Coming up with ways to improve the axle...
Using a taper-lock hub on a tubular axle, sized to fit inside the carriage tube. 

[SparWeb]

This past week, I've made a lot of progress on this machine.
I replaced the hubs - not quite as shown above because I found a much simpler way: keyed shaft stock.
I also made a set of rails for it to roll on, which will eventually become a complete table.
I bought some proper cutters, but not left-hand turning cutters.
I still plan to use the cable system, but currently not using it, and I have decent results without it, actually.

Today I turned out a reasonable copy of an arbitrary 2D shape.  Later I will try it on some 3D shapes but I need to set up proper fixtures for doing that.

[SparWeb]

Exactly 1 year later, an update:

https://www.youtube.com/watch?v=jwORuhzXiTY

I can successfully duplicate wind turbine blades with this machine.
Below, a photo of a finished product.  As stated in the blurb under my video, this is just a dry run of the machine to show that it works now. 

[MattM]

Pretty time consuming by hand.  I wouldn't be surprised if it could be automated for a reasonable cost.  So many tooling options out there these days.