CHMT36VA pick and place machine digest

28, Dec, 2020

1. Component height makes no difference and nozzle hitting too hard on PCB?
Notice that changing the component height value does not change anything in my CHMT36VA?
When setting 0805 resistor with 0.5 height and the nozzle hit the PCB very hard. I tried to change to 1 or even 1.5 and I do not see any difference. Maybe my machine is not calibrated. Sometimes hit so hard the component bounces and lands in another position.

The manual is useless about this.
There are 2 places to set the height (stack and component) however I noticed only the 'component height' is considered at both pick up and drop off. To me, it would make sense to have 2 different heights for pick up and drop off but nope. So wherever the component is sitting before pick up it must be at PCB surface level (noted).
The software does not help too much either. I have not found a way to test how low the nozzle goes.
I wonder if the number set in height is anything accurate. I do think it does affect the nozzle's lowest point, however. However between 0.5mm and 1mm it might just mean 0.5mm is a bit lower than 1mm.
That's my take above for now. If anyone knows his stuff about adjusting height please step in and tell us.
The conclusion that the height setting controls the velocity at which the nozzle hits the part or PCB, not the actual level the nozzle will drop to.
A buddy make some 18mm tall Delrin posts to support the PCB(s) at various strategic places. They're held in place to the platen with double stick tape and prevent the PCB from flexing and vibrating during the placement of parts.

2. The camera image is black
My 36A has been sitting idle for about a month. When I went to set up a job today, I ran diagnostics to check that the cameras were working and the camera images didn't come up and the screens were black. I have had the issue of a white blank image which I could fix by unplugging the USB connections and then plugging them back in. Or sometimes I need to shut down the software or the machine itself to fix the issue. But this is the black screen is new and I can't seem to get any image at all.
Problem solved, sort of. I removed the drivers and then re-installed them. Then it took about a dozen restarts before any images showed up on the cameras.
I had a similar issue, when the software did not pick up my machine, but rather my USB microscope, which did show a blank screen. Replugging helped, and I need to use specific ports, I guess the software always picks camera no.
Workbench Pick n Place Machine
CHMT48VA or CHMT48VB pick and place machine

3. Differences in vision-to-nozzle offset inboard/component areas?
I'm noticing the following issue with my CHMT36VA. I switch between Head/Vision, in the Position-Component dialog. In the board area the alignment is excellent. But in the "loose components" area, there is a consistent 1mm(!) y-direction offset. And in the feeders area there is a consistent 1mm xy-direction offset.
Any ideas why vision-to-nozzle offset could be different by 1mm in different areas? I first guessed, it could be due to different hight of the areas, but no, doesn't make much difference (in the loose components area, I've tried adding padding, to test it), This looks like a software bug. And strange one at that. Any ideas? Is there a secret password, by chance?
I think this is caused by the general calibration, there's some 'R factor'. there was a discussion in this group on how to set it for both X/Y axis using a 20cm ruler.
The offset between vision and nozzle is supposed to be constant and invariant to location, right?
If the R-factor was wrong, we'd see offset_camera_to_nozzle multiplied by it and we'd see the same error, regardless of the location. But I'm using the same exact dialog, just aligning vision to different locations. And in the board area, it looks like <0.1mm error, while in pickup areas 1mm error!
PnP Machine from China