I try to understand the PCB Marks settings. I have 2 marks as needed. As I understand it, I set the PCB origin via the camera. Then I set the values for the marks too, that all works. But since the software does not know where the marks should be it just detects them, but that does not make much sense to me. What does it do with the values after detection?
On my other pnp machine I had to enter the coordinated of the marks, the machine then searched on these coordinates and detected the marks. It then calculated the daviation of the real position and calculated the offset. That way it placed the parts perfectly, also when the pcb was moved a bit. To make it perfect, it detected the coordinated from the importfile by itself as it used parts with names FID* for the fidicuals.
Your way does not make sense to me, I can detect nice marks, but the software cannot use the data as it does not know where the marks should be in offset to the pcb origin.
I currently run tests on my new VP-2500DP, and have offsets in the placed parts. I entered the PCB origin exactly, but there is an offset on all parts. So now I need to shove the origin until the parts are pleace correctly, not a very good thing. Better would be fields to enter the X and Y coordinate mark 1 and mark 2, and the software then detects them and calculates the offset.
ZitatI try to understand the PCB Marks settings. I have 2 marks as needed. As I understand it, I set the PCB origin via the camera. Then I set the values for the marks too, that all works. But since the software does not know where the marks should be it just detects them, but that does not make much sense to me. What does it do with the values after detection?
So far so good you know how mark points work! The PCB have deviations in X or Y direction and positions may not exactly as defined by CAD system. We recommend you teach the mark points exactly to reduce these and detection deviations. After Mark point detection the software calculate angle and offset and update for each part position in placement data! (what else should the software do?) It is not recommend to search mark points in working area what crazy idea the PCB is on a defined position and hold by pcb holder. It's only necessary to compensate deviation from this position because of manufacturing deviationss of PCB outlines. (Refer to VP manual [V2.036] chapter 3.1, 7.9, 9.1, 13)
ZitatOn my other pnp machine I had to enter the coordinated of the marks, the machine then searched on these coordinates and detected the marks. It then calculated the daviation of the real position and calculated the offset. That way it placed the parts perfectly, also when the pcb was moved a bit. To make it perfect, it detected the coordinated from the importfile by itself as it used parts with names FID* for the fidicuals.
This is exactly the same way we work too except the way you are talking about coordinates. We calculate the coordinates exaxcly as PCB cad system does referred to PCB origin. And naturally they are defined referred to PCB origin in your CAD software too. One clever improvement is to set a mark point on PCB origin for easy setup!
ZitatYour way does not make sense to me, I can detect nice marks, but the software cannot use the data as it does not know where the marks should be in offset to the pcb origin.
Please read the message above!
ZitatI currently run tests on my new VP-2500DP, and have offsets in the placed parts. I entered the PCB origin exactly, but there is an offset on all parts. So now I need to shove the origin until the parts are pleace correctly, not a very good thing. Better would be fields to enter the X and Y coordinate mark 1 and mark 2, and the software then detects them and calculates the offset.
How about to calibrate the machine well and use the manual? If offset is increasing over PCB area in one or both directions: Check the travel distances (calibration) as described in "Visual Placer Maintenance manual" because you use a belt machine and calibration is depending on temperature. Only X and Y axis need to get checked. (chapter 6)
If offset is constant and parts aligned by camera Calibrate the camera center positions to nozzle center. (VP manual chapter 8.2)
If there is a deviation between head1 and top camera Calibrate the top camera distance.
Here is chapter 13 check list 13.4 Check list for machine adjustments to receive a proper placement: 1. Set the PCB origin and check the center positions of some parts using the top camera. Adjust the PCB origin until parts matching. Note you need to set the mark center position again after changing the PCB origin!
2. If parts placed out of the middle after alignment check / adjust bottom camera center settings in camera setup.
3. If parts placed randomly wrong check the Z height settings and slow down Z speed. (increase the put delay)
4. If parts placed wrong on far positions check the machine calibration or slow down the placement speed. First step slows down Z speed!
5. If parts placed wrong after proper alignment choose right nozzle and slow down speed.
6. Increase the “Put Delay” in feeder settings to keep part in position after vacuum closed.
7. It’s important to adjust the pick-up positions too because feeder problems will cause placement problems too. For plastic tapes use always a local Nozzle height setting because parts are not Z aligned to the top of the tape!
8. For 0402 parts it’s sometimes necessary to modify the feeder top spring length to access the second part.
9. The last important thing is keeping the nozzles clean because dust and paste will reduce the suction force.
10. Use Visual Origin to improve machine position precision. You find in basic settings. Adjust the mark detection parameter and take over the position of visual origin for reference! The machine will go there after every reset and adjust the machine origin using this mark point.
The machine is calibrated, that is not the problem. Maybe I explained it not too good.
I now select the pcb origin, but since that is never the same in 2 pcbs we must rely on the marks. Now when my Origin is not where it should be I have a small offset in every part.
The manual writes that I then have to adjust the origin until the parts are placed correct. Trial and error, with real parts needed to be placed. We could avoid this trial and error if we could enter the real coordinates of the marks, we could even select them from the part list, eagle exports my marks as parts. Maybe context menu "Select part as Mark1 / Mark2". Then the software knows where they should be and could calculate the exakt pcb origin from that data very easy. That is how other p&p software does it. Its very easy and exact.
For example: Mark1 is in local pcb cordinates at X=10, y=15. I set my coarse pcb origin in machine coordinates at X=70 Y=-315 It can now look for mark1 at X=70+10 and Y=-315+15 It will probably find them at something like X=80.57 and Y=-299.89 The real origin of the pcb is then X=80.57-10 = 70.57 and X=-299.89 - 15 = -314,89
It will then hit every part exactly. Now it all depends on how exact I enter the origin of the first pcb I measured. If I do that badly, all subsequent pcbs are placed with an offset.
But however, i do not think you will change that.
One more question is the "Using manual mark point set" in the pcb setup dialog. There is also a "CameraGetMark1 Offset" in the context menu of the panel. What is that for?
You do the alignment only for PCB job setup, the machine do the alignment on the next PCB's using the mark points.
You adjust the pcb origin and check the part position by camera and adjust pcb origin again if there is a deviation. That's the information from manual! However You can add your mark points to pnp list. Use the ricght click function in part list to send the camera to MArk (PART) position and take over the to the mark point settings. You can also do this manually!
ZitatOne more question is the "Using manual mark point set" in the pcb setup dialog. There is also a "CameraGetMark1 Offset" in the context menu of the panel. What is that for?
The function is for manually mark point adjustments forget it!
" the machine do the alignment on the next PCB's using the mark points."
When does this happen? What triggers this? This is all very unclear to me - how one sets a new panel in the machine and then triggers the machine to read the fiducials. Can you please explain in a few more sentences.
Do the fiducials need to be in the parts list? If so do they need a feeder assigned?
I am using panelised boards and I use the fiducials on the technical rails. The fiducials are read once for each panel or each time you stop and restart the panel.
The boards are setup by defining the row and column spacing in the PCB setup screen. I have a strange issue in that my panels on the topside align perfectly when I flip them over to the bottom side there seems to be a slight rotation of the panel ie the top right everything is shifted down and bottom left everything is shifted left.
I compensate for this by shifting the plate the panel pushes against slightly when I switch to doing the underside of the boards. I don't understand why the top and bottom are not the same.
Did you checked the manual about mark points setting? (Latest manual online)
Zitat" the machine do the alignment on the next PCB's using the mark points." When does this happen? What triggers this? This is all very unclear to me - how one sets a new panel in the machine and then triggers the machine to read the fiducials. Can you please explain in a few more sentences.
If you run a placement job and enable the mark point checking in PCB settings! The machine will check the mark point positions and adjust the measured offset and angle first. After this machine start placing parts.
Do the fiducials need to be in the parts list? If so do they need a feeder assigned?
ZitatI am using panelised boards and I use the fiducials on the technical rails. The fiducials are read once for each panel or each time you stop and restart the panel.
The boards are setup by defining the row and column spacing in the PCB setup screen. I have a strange issue in that my panels on the topside align perfectly when I flip them over to the bottom side there seems to be a slight rotation of the panel ie the top right everything is shifted down and bottom left everything is shifted left.
I compensate for this by shifting the plate the panel pushes against slightly when I switch to doing the underside of the boards. I don't understand why the top and bottom are not the same.
Any ideas much appreciated.
I really don't understand what you're doing? For the bottom side you need separate placement job and mark point settings. You need to mirror your placement data before you import to our software. Flip the PCB in your CAD system and set the PCB origin. Then export data again.
By shift i was meaning by half a mm or so and yes had setup mark points and had correct placement data. I finally fixed the issue through calibration of x and y axis and alignment of the top plate the PCB panel pushes against.
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