View Full Version : Tracing eye and MACH 3

08-13-2006, 05:10 PM
I've been given a Burny3 controller with a tracing eye(and gantry,motors, gear boxes, and drives). I want to run M3 with a MP-1000-THC and gecko's. I'm wondering how I could hook this up so the eye could teach mach a part.

Will I need to keep the burny?

If I need to keep the burny how do I hook up 2 different drives?

What cheap THC options are there that will allow me to just run the burny?

Idealy I would like to run just M3 with an eye and skid the burny control.

Help!!!!! :drowning:

08-15-2006, 08:51 PM
Why in the wide world of sports would you want to run a modern plasma cutter with an electric eye? I spent a month retrofitting one of the old eye controllers on an oxy/acel table and converting it so they could control it with MACH3. They wanted me to leave the design it so they could plug the eye back in and do back to that method. IT cost them an extra 1000.00 to make it dual purpose. To my knowledge after the first cut from the computer they have never used the eye again.

It was a pretty neat design since it's basically a servo system (even has a +-10V servo amp inside. Only problem is that it was designed to move (and trace a line) at 10 to 20 IPM for cuttin 3" > steel! I doubt it would accurately follow a line at 300 IPM for thin plasma cutting.

The "eye" needs a high contrast drawing (heavy black lines on white papaer). It also needs a line (not just an edge) since it senses it's way by measuring the error from both sides of a line. It won't "scan" a part and give you a drawing either. I doubt it could be used for that.

Your 100 times better off (unless you have lots of existing drawings of parts too big to scan that you need to continue to make) to use the CAD->CAM->Controller approach to generating parts.

There is no way that MACH is going to work with the old Burny.

The cheapest THC option is called a drag tip. Put on a drag tip and build a spring loaded floating head. Slam it down, pierce and drag it around. Works okay in simple parts where no cut is within about 3/4" of another. Good news is that when you get ready to do a real THC you can use the floating head for material sensing. :D

08-16-2006, 09:40 AM
I just want the ablility to use the eye to teach a part. It looks like I may have to **** can that idea!

08-17-2006, 03:37 AM
Could you use the eye simalar to a digitzing probe?
Instead of probing down until touching and moving over could you say, "probe" in the X direction until the eye sees the line and then step over in Y and do it again? Basicly using the eye as a switch?
Of course you could do the same thing with a scanner and CAD software and bitmap-vector software, but what if the part you wanted to duplicate was to big for your scanner? Once you have the points maped in as G-code you could use a G-code to DXF converter to put it into CAD and modify/clean it up if you wanted. If it is on a plasma any way then any roughness might not even be noticable. It will take a while to "scan" but then you could cut it using Mach at whatever speed you like, as many times as you want.
Just a thought.

08-17-2006, 09:37 AM
The "eye" is made to sense a high contrast line on white paper...period. The head spins and uses mirrors and it's focal distance is pretty narrow. Trying to make this into an optical probe is like putting lipstick on a pig. Ragged artwork cuts poorly on plasma. The machine has to slow down to do all the sawtoothed moves and that causes cut problems. Since plasma has a "floppy" tool rapid changes in direction at slower speeds causes an actual amplification of the ragged cut. We spend hours cleaning up artwork so we can get smooth edge cuts.

Tom Caudle