Monday, October 06, 2025
Tried new probe holder - 10μm Pixels!
I've been building up to a resin print test campaign, starting end of next week. So have been working hard on getting V0.05 into a usable state. Hardware is running quite happily down to 10μm per pixel, even in engrave mode. Here's the hackaday.io "Jolly Wrencher" logo etched into Sharpie marker. That's a 50x50 PNG done at 10μm per pixel, making the whole thing 0.5mm wide. Zoom in and you can see a bit of a gap between pixels, so I might even make 8μm.
This is a big little deal. Achieving 10μm is what I said I'd be happy with as a positional accuracy goal for this prototype. Of course, I need to get the resin going still. But the reason I picked that number is that it was the feature size of the original Intel 4004 CPU, and it seems to me to be some kind of tipping point.
Below is the new probe holder, allowing three degrees of freedom. The new probe holder requires you undo one of those vertical screws at the top to remove it, and requires a bit of fiddly setup to get the length right. But it is much more easily positioned over the UV source than the V0.03 design, and as V0.05 has such a massively improved range of motion on the Z axis you don't need to manually adjust it so often - just wind the Z axis up out of the way.
Below is the view I get on my "microscope' console with the print about half way through. The other console is taken up running cnc-js. Using mpv with custom pan/zoom macro keystrokes on the keypad instead of vlc has made the view much more useful.
Oh, note that the 10μm image was doe using a 0.5mm hypodermic needle, not even a fine tip probe. That's the big, fuzzy grey thing centre to top right.
List of To Do's is growing a bit. I want to run resin tests using a hypodermic, after seeing how it did in the above test. I want to test Z Touch on a doubled sheet of aluminium foil to give me actual numbers on the thickness of the foil (which I shoulda done and never did). Finally, the bugbear of having to do version control and docs is getting kinda important.
Just as well I'm kept up at 3am my a helluva storm raging outside, ay?
