Hello all, I'd like to incorporate the design of stained glass pieces with the ability to cleanly cut out shapes using CNC. I would like to use an Openbuild CNC machine that utilises the cutting knife head shown below instead of a cutting drill head. When cutting glass, what you are actually doing is scoring a line with pressure applied to a carbide cutting wheel, then pushing this wheel in the shape of the glass that you want to cut. This score provides a weakness in the glass that causes it to break cleanly. In the picture the tubing is for oil lubrication of the cutting wheel, which is stored in the silver cube with the golden hat. All the glass cutting machines that I can find are all huge industrial units that have multiple heads for cutting standard float glass/mirrors. Nothing for a small scale hobby use. Thus, I want to accomplish the following; 1 - use a CNC machine to move a cutting blade in complex shapes over a glass surface 2 - apply a consistent force of 15-lbs to ensure glass is scored effectively, but not to shatter it. I'm throwing this out there in the hope that some thoughts can be put together for the community as a whole!
Really doesn't seem that difficult physically, simply a case of putting together a small system that won't flex as the load is applied. The issue is achieving the 15# pressure and then the additional pressure to cause the fracture. And again physically achieving that is not a big deal, a simple low pitch screw on the Z-axis and a pressure gauge (load cell) to tell it when to maintain the pressure. The real issue is the software needed to run this. That's going to require someone with programming skills....
You're right, it's not that hard to put together the hardware - and like you say, the real issue is when you need to maintain the force applied via a load cell and it's controlling software.
Would 2 identicle runs of 7.5lbs be the same as 15lbs, and so on? I think the operator could do the "final break" at the end maybe. A known spring pressure could do the job, with a switch to stop the downward movement and hold the position until the next upward movement.
Just set the "cut Depth" for the desired spring force. Calibrate using a scale and see how many mm of down movement you need to achieve 15lbs of force. Then when you program use full single pass full DOC, the DOC is set by whatever you need to get the compression and force. The attachment in the pic already looks like it has the dual rod slides so the spring might already be there? 15lbs down force is nothing for a tr8*8
Why Not Just Use a Adjustable Spring Loaded Diamond Drag Tool , There are quite a Few that just fit into a Standard Collet , I would think that any Industrial Grade Diamond is Harder than the Glass, So Should Score it Enough to put the weakness in the Structure for a manual Break ? I did a quick Search on Poogle - and found this : Diamond Drag Engraving Tool Much Less Complicated than the Above Mech - Just an Idea !