I use the focus gauge but my engraves still vary. Is there a way to verify focus rather than trust the spacer?
How do I know if my focus is actually right?
3 replies
Marcus ValeAdmin · LP53 weeks agoYes — do a focus ramp test. It takes two minutes and it's definitive.
- Prop a strip of scrap at a shallow angle so one end is a few mm closer to the lens than the other.
- Engrave a single line at low power along the length of the ramp.
- Look for where the line is thinnest and darkest. That's your true focal point.
- Measure the material height at that point. That's your working distance — compare it to what your gauge gives you.
Most gauges are accurate, but they assume the module is mounted at nominal height and the bed is level. If your ramp test disagrees with your gauge by more than 0.3mm, trust the ramp and shim accordingly.
Also: focus drifts if the module mount is loose or the material is bowed. Flat material and tight bolts before you blame the gauge.
Hugo MarchandLP4 Safeguard3 weeks agoRamp test showed my true focus about 0.6mm off the gauge reading. Engraves are noticeably crisper now. Great trick.
Sana QureshiLP43 weeks agoKeep the ramp test piece. When you suspect power loss later, re-run it on the same material and compare — it separates focus problems from lens problems.