Machining Glass


(Nicholas J Mathis) #1

Hello all,

I need to accurately cut 1.12mm thick glass sheets for a scale model. Mostly precisely placed holes and outside dimensions that include a curve.

I found this: http://benkrasnow.blogspot.com/2011/08/cnc-milling-glass-plates-and-mirrors.html

Questions (that I can think of):

  1. What is the best coolant to use? Can I use water as a coolant?
  2. If I submerge the glass in a tank of coolant (to contain the mess and particles), is that okay?
  3. Are there any nuances to diamond burrs I need to consider when buying the cutting tools?

Image of the glass I need to cut on Nomad 883 (for illustrative purposes):


(William Adams) #2

It’s been done — usually using a diamond burr bit with the material submerged in water — the problem then becomes one of safely disposing of the glass debris in the water (apparently it’s potentially damaging to municipality water treatment filters). Another possibility is the glass shattering from internal stresses.

I considered it problematic enough that I didn’t bother to make note of the instances when this was shown on-line at: https://www.shapeoko.com/wiki/index.php/Materials

Anyway, here: http://hackaday.com/2014/12/04/cutting-glass-with-cnc/


(William Adams) #3

Went ahead and added that: https://www.shapeoko.com/wiki/index.php/Materials#Glass (and a link back here, so now it’s circular).


#4

Re: disposal of the residue.

I have dealt wit this a few times for several materials that are not suitable for the liquid waste stream.

Contain the material and water in a tray that can be removed and left out for the water to evaporate. The tray may need to be made to hold the part. Place a disposable towel (I use lintless blue shop wipes for this) on the surface. It will sink as the water evaporates. When it gets down to moist muck in the bottom, wipe the muck out and dispose of appropriately. If the container needs further cleaning, rewet and a fresh wipe to repeat the process.

If it is possible to put a towel in the bottom before the work, it is easier, since the waste will be trapped between the two layers. I have done this with success when using a water tray below to catch runoff while drilling glass.


(Jonathan K) #5

This is what a utility sink with a plaster trap would be helpful for… if that’d be sufficient. Don’t know how much the glass particulates would settle out or not. Solids that don’t belong in the water system are a common problem that dental practices and art studios both deal with in their own way with trap systems. Something like: