CHMT530P4 Setup tips - Page 1
Forum section: electronics / general

author: Pooldawg
author_rank: Contributor
timestamp: May 23, 2019, 07:09:44 pm
content: Hello EEVBloggers!I recently received one of these machines and have a write up started. I will put it up as a get through this.I am having some problems with the components being placed. The are getting placed off position slightly and rotated.I saw some people said the machine auto finds the fudicials, how do I enable this? When loading the board it comes up with 3 components to calibrate to.This becomes a bit of a judgment call even more so once the paste has been put down.I basically have to tweak all the ICs a bit and this either ends up making no solder point or shorts because the paste either sticks or all pushes.I tried the two point setup on the components, but this didnt seem to help.Thanks for any tips and tricks on getting the machine up and running!

author: pysco68
author_rank: Contributor
timestamp: May 24, 2019, 06:39:34 am
content: Hi Pooldawg,Here's what I would look after:1/ fiducials / ref components should be far apart to lower rounding errors. Ideally 3, at the furthest possible corners. If you use pads, double/tripple check the pad coordinates. I had dumb issues with ECAD footprints generating off center "centroid" coordinates....2/ there's no "auto find" fiducials. You basically tell the machine where they should be, teach the vision system the "Eigenvalue" of the fiducial (on machine) and then I compares the machine coordinates to the expected ones and rotates / translates everything else accordingly.3/ be aware of the placement height. If you told the machine to do "0" always, it might happen that the component rotates/slides every so slightly when the paste is squasched out when you "ram" the component down.4/ play with the "wait before lift/release" parameters so that the nozzle vaccum has time to fully release before retraction5/ reduce machine speed to test6/ have a look at what the vision system sees (in step by step mode you can watch what it does nicely). I had my learning curve there. Make sure there's no stray light andclose the lid(that matters!)7/ check board origin in the diagnostics menuHope this helpsBtw. I own a CHMT560P4

author: Pooldawg
author_rank: Contributor
timestamp: May 24, 2019, 08:49:40 am
content: Thanks Pysco!1/ fiducials / ref components should be far apart to lower rounding errors. Ideally 3, at the furthest possible corners. If you use pads, double/tripple check the pad coordinates. I had dumb issues with ECAD footprints generating off center "centroid" coordinates....I will check centroid values coming from altium - When you say pads, do you not mean center of the component? The tool picks 3 components, and I have been picking the center of those components.2/ there's no "auto find" fiducials. You basically tell the machine where they should be, teach the vision system the "Eigenvalue" of the fiducial (on machine) and then I compares the machine coordinates to the expected ones and rotates / translates everything else accordingly.What is Eigenvalue? I think it doesnt find the fiducials because I remove them so it doesnt try to put them into a stack? Maybe I should leave them there? Or can I add them manually from the machine? Is it better to use fiducials instead of the 3 different corner components it picks?3/ be aware of the placement height. If you told the machine to do "0" always, it might happen that the component rotates/slides every so slightly when the paste is squasched out when you "ram" the component down.I adjust the height of anything that is not passives. Although the caps are .8, I left it as .5 by default. I am not really have to much of problem with caps. Some are a little sloppy. I can change them to .8 to see if it improves.4/ play with the "wait before lift/release" parameters so that the nozzle vaccum has time to fully release before retractionI will do a double sided tape run tomorrow and see if this makes a difference.5/ reduce machine speed to testI slowed it down to 80%. I think the user guide said something about not going any slower?6/ have a look at what the vision system sees (in step by step mode you can watch what it does nicely). I had my learning curve there. Make sure there's no stray light and close the lid (that matters!)I can see the head placement. I didnt notice a way to see the down camera placement. I will close the lid. I turned the lights off in the room at 1 point, but that was WAY early when I was trying to troubleshoot a passive issue. I will try this again.7/ check board origin in the diagnostics menuWill do!This is my first pick and place machine ever. Its been quite a learning curve! But its been fun making all the individual progress! I really appreciate you taking the time to respond.I almost paid the extra 1k to get the 60, but the 30 is big enough already! I would have to give the 60 its own room!

author: Pooldawg
author_rank: Contributor
timestamp: May 28, 2019, 06:27:27 am
content: In addition to below. What are Eigenvalues? How do I calculate them? When I google it starts talking about sine/cosine.I switched to Mark points and I picked 3 test points.Question when calibrating, do you pick center of the hole - or center of where the part should be? (if PCB placed missed the drill by a little bit).

author: Pooldawg
author_rank: Contributor
timestamp: May 28, 2019, 06:33:14 am
content: Here is an update of switching to a Marked component, and running the machine in the complete dark. It comes out the same.In diagnostic mode- The pcb corner is off just slightly on the Y plane. I couldnt find how to adjust it.In the calibration section - I calibrate the look up camera so that the center of each nozzle is over the camera. When I do the down camera, it is way off base somewhere. When I pick the down camera is it where I am suppose to use the black PCB and line up under the down camera first?The documentation doesnt match the latest firmware in the machine.Gets a little frustrating at times :/

author: Ribster
author_rank: Frequent Contributor
timestamp: May 28, 2019, 06:59:43 am
content: Quote from: Pooldawg on May 28, 2019, 06:27:27 amEigenvalues are the own coordinates of the machine.

author: pysco68
author_rank: Contributor
timestamp: May 28, 2019, 10:08:42 am
content: Actually the Eigenvalues are a sort of optical fingerprint of a region that the vision system matched. In the end it will allow the vision system to match the fiducial even if it is off-center because it should be the only matched "thing" with that particular Eigenvalue in the field of view.I'll have a look at your pictures again later, I'm on mobile right now

author: Pooldawg
author_rank: Contributor
timestamp: May 28, 2019, 08:51:12 pm
content: I've gotten it better!The bga is off slightly. Is there a way to see the down camera when it is placing the parts?I aligned the heads and it works pretty good.I am going to continue to tune it in!Its so close, I could probably make this work.I think I need to remove some of the solder paste, the parts datsheets call for .1 to .125mm stencils, and I ordred a .2mm stencil. I think maybe I should wipe some of it away, the one chip isnt sinking down to make contact.Progress!

author: Smallsmt
author_rank: Frequent Contributor
timestamp: May 28, 2019, 08:59:33 pm
content: QuoteDo yourself a favor and order a thinner stencil (0.125mm) the whole work is probably for nothing otherwise.30% of the work is good paste printing.And among the BGA that's really not good to have too much paste.

author: Pooldawg
author_rank: Contributor
timestamp: May 28, 2019, 09:18:34 pm
content: I went back and looked at my order, it is actually a .12mm stencil. My last one was .2.Thanks for the feedback! This is all new to me. Fun ... frustrating... waiting for fruitful

author: Pooldawg
author_rank: Contributor
timestamp: May 28, 2019, 09:23:18 pm
content: How do I calculate the Eigenvalues of the fiducials? Google gives me no help

author: pysco68
author_rank: Contributor
timestamp: May 29, 2019, 07:51:36 am
content: Hey Pooldawg, looks better,I was pretty sure it had to do with the machine coordinate alignments as the offset seemed to be fairly consistent across the board - litterally.Regarding the Eigenvalues, you don't calculate them, you use the fiducial teach-in procedure in the machine (you can't even set the value in CHMT's editor I think). Go to the machine program editor, to the tab with the fiducials and edit each one, then follow the "calibration" procedure. This sets the Eigenvalues.You can check it by exporting the DPV file again and looking in the right section. The Eigenvalue is the number in the "Type" column.Basically we have 3 fiducials at (8:97.5) (91:2.5) and (8:2.5) (coordinates in MM from board origin - which is the notch in the PCB holding rail usually)In my case if looks like that:Code:Table,No.,ID,offsetX,offsetY,Note,Model,Type,DevX,DevYCalibPoint,0,1,8,97.5,Mark 1 (tl),8629,1,0.0,0.0CalibPoint,1,2,91,2.5,Mark 2 (br),8617,1,0.0,0.0CalibPoint,2,3,8,2.5,Mark 3 (bl),8665,1,0.0,0.0Btw. we wrote our own generator so it may be your file looks a little different.

author: pysco68
author_rank: Contributor
timestamp: May 29, 2019, 07:56:20 am
content: Btw. we had an issue with a SOD123 diode which was consistently rotated by 4° when using the vision system. We ended up disabling vision completely for that one. I read somewhere that some people had issues with skewed parts on QFP(not sure?) and they applies a correction angle in the placement file to fix the issue. I think you can read that somewhere on the EEVBlog forum (I think it was about a 530P machine)

author: Pooldawg
author_rank: Contributor
timestamp: May 29, 2019, 05:25:10 pm
content: Pysco68 -As it turns out - The new calibration stuff didnt help to much when I did the run alst night. Items had still been shifted.Do you add those calibration points directly to the file? I didnt even see those as an option. Also, my 3 fiducials arent in those 3 locations. 2 of them are close, and 1 is far away.It is more like bottom left - mid left - top right.It really is getting frustrating. I've got to adjust any of the qfn/fine pitch/parts.I tried to use the two points method on the FPGA with the top left ball and bottom right ball - It didnt make a difference.Charm high is 100% silent for over the past week.

author: Ribster
author_rank: Frequent Contributor
timestamp: May 31, 2019, 05:28:11 pm
content: Pooldawg, i can confirm Kimi is active.I've been emailing her this week to order a 560P4.Think you should get the right person on the mail i think.