- Start cut beyond the edge of the glass if possible. The piercing cut will shatter a region of the glass equal to a couple times the glass thickness, even in low pressure mode.
- Cover the glass in mylar tape to help prevent scratching, and sandwich between thin pieces of aluminum.
- DO NOT USE ABRASIVE.
- Other than that, it's easy!
Fixing Marring from Lead-Outs
The following is an email from Adam West:
Using the waterjet yesterday I noticed something a little off – after performing a cut there was no lead out. Instead, the nozzle would stay at the end point of the cut, whilst firing for a second or so. The result of course is that you get a little notch at this position due to the dwell time. On further inspection what was happening is that when importing the drawing to Make, the lead out lines were being removed, whilst the lead in lines remained.
The fix to this is fairly simple, when importing to Make, a screen appears – the one where you choose material and thickness. In that window is a button for ‘machine options’. The resulting window has a tab of lead settings. The option ‘minimise lead out length’ was checked. Thus the lead out length was very small resulting in the nozzle effectively just staying in place for the associated dwell time. By unchecking this option you get your lead outs back, and slightly improve the finish quality.
After this I also changed another option which was ‘offset leads’ – this means your lead in and lead out are at slightly different positions (offset by something like the width of the cut). This is noted to be a recommended setting. Enabling this results in a much better finish – on some pieces the leads are not noticeable, and if they are, the imperfection is a small bump on the material, which is much easier to fix than a notch.
The settings are remembered so you don’t have to change them each time, and are currently in the configuration described here.
Hopefully this is of use to people – feel free to forward to other waterjet users. If you have any questions come see me.