LitePlacer.com forums

:D _So there’s a 50KHz pulse rate limit on the TinyG output, which equates to 30000mm/min with stock Liteplacer hardware. The G251X can handle up to 300Khz, if you’re running 1.8deg, the TinyG will be able to handle 60000mm/min. Other options for 0.9 deg is to 5 uStep and use one of the other Geckos...

So turns out we’re both wrong, it’s not Stepper Resonance or Bearing Skip. I decided to do some more experimenting to prove to you why it can’t be Stepper Resonance, because: 1. Stepper Resonance is at a lower frequency then we’re seeing here (just do the calcs) 2. Stepper Resonance is under low loa...

What software gives more accurate result without vision? I heard that the openpnp is very inaccurate, unlike the liteplacer software I would say the opposite. I've used Liteplacer software for a while, without being able to place 0402's accurately. WIthout Bottom Vision, OpenPnp and Liteplacer have...

Incremental torque decreases as you increase microstepping: https://hackaday.com/2016/08/29/how-accurate-is-microstepping-really/ Essentially this means the ability to hold or move to a microstepped position is less accurate. However microstepping also reduces noise and resonance, it's a tradeoff. B...

Have you tried loosening the v-wheels slightly so that they still grip the rail but can be scrolled manually? Yes, tried everything from tight (moving wheel manually moves the head) and loose (wheels move without moving head). Does your maximum speed decrease while increasing current? Mine does: ht...

Why so long?? It's 250 ms by default I've been testing with 0402's and with no adhesive or paste on the board. 0402's are light and need a long release time if there's nothing to stick it to the board. The reason is some of my parts I don't want contaminated with adhesive. I find the adhesive from ...

Also, worth adding that I pushed the Z axis too, that one I can identify the bottom right bearing as whining near the limit
(Easier to localize audibly).

Very interested to see how your new servo steppers work out, I’ll switch too if you’re getting significantly better speeds.

If you try speeds more than 14 m/min, you will see that this sound will decrease with speed until the motor stalls. So I revisited this today. Any speed >=12000mm/min started whining. At 18000, the steppers gave up. Tried at various acceleration speeds (250, 500, 1000) and tried reducing step count...

> And for comparison purposes, this is the same machine and settings in OpenPNP but with the Up Camera not used for placement. What is your pickup vacuum time? I got such imperfect placement when i had 50 ms, and it turned (relatively) perfect when i set 100 ms (and further increments had no effect...