Quad QSA-30A will arrive tomorrow

[SMTech]

IPC speeds were intended to cut down on the cheating of these numbers as it does apparently specify a mix of parts on a test board. However there seem to be subsets of the test for specific cases quoted by some manufacturers (they put a package size in brackets and things like that) that allow them to game the numbers. It is still a more useful number than the "optimum speed" BS you will also find, and the contrast between those two numbers also tells a tale.
Due to the way they work its much harder to game the numbers on a turret head, it picks one at time until it has a full turret and then it places them, there can never be a gang pick. Equally high speed turret heads are never flex heads and are basically exclusive to a chipshooter role placing things often 5mm high or even less. If you have an application that can exploit gang picking on a machine with 8+ heads tho' it could be virtually unbeatable but that's what... LED placement ?
Flex turrets like you find on a Europlacer or an ASM E-place (look at the difference between a CP14 and a CP12 head https://www.assemcorp.com/en/products/production/surface-mount/asm-siplace/urun/3701-e-by-siplace.html) are way slower, probably very little difference to many users between them and the inline heads.

[jmelson]

OK, I definitely needed the most flexible machine I could get, I only have one.  And, my old Philips was limited to 6.5 mm height.  I forget, but I think the Quad QSA can go up to 12 mm height.  That should cover anything I'd ever need.
But, I had to watch what I specified for the Philips, I could have easily designed in a tall electrolytic cap and been in trouble.  Also, the Yamaha feeders on the Philips just couldn't handle tapes with anything taller than about 5 mm, it lifted the tape out of the sprocket.  So far, I have not seen any of these issues with the Quad feeders.

Jon

[sarason]

Jon,

Send me a copy of a your original CAD file and what you think the output should look like,
I will endeavour to add it to PCBSynergy

My email is on the PCBSynergy web page.

sarason

[jmelson]

Jon,

Send me a copy of a your original CAD file and what you think the output should look like,
I will endeavour to add it to PCBSynergy

My original CAD data is from Protel99 SE (with SP6).  The Quad QSA30 (and apparently Samsung CP30 and CP40)
put the board origin at the lower right corner.  So, I set that corner as the origin in Protel, and then all X coords are negative.

For the top side of the board, I just convert minus to plus.  For the bottom, I have to offset the coords by the X dimension of the board, and mirror the rotations.  But, I have a program that does all that, and it seems to work perfectly.  The binary .pcb files on the QSA are an undocumented 64 - 96 K of inscrutable stuff.

Jon

[jmelson]

I spent the weekend doing a bunch of calibrations and tests on the #3 head, which had been giving trouble, and got it to where it ran pretty reliably doing a test 3-piece assembly onto Scotch double-sided tape.  Today, I ran 12 boards with 117 parts on the back side.  I did a couple more tweaks to get optimum placement.  It ran through 1404 parts with minimal issues after those last tweaks.  And, the ANC is working perfectly, now!

Jon

[jmelson]

Well, the saga continues.  I have done a couple not very demanding boards with quite good results.  Now, I'm doing the top side of the board that started this whole upgrade.  It is a 4" square board with a mix of (for me) fine lead pitch devices.  There a 144-lead FPGA and 8 MSOP10 chips with 0.5 mm pitch, and 5 SSOP24 chips with 0.65mm pitch, and an SSOP16 that I guess is also 0.65mm.  My old Philips machine could not place any of these within half a lead pitch, so I had to put every board under a microscope and poke each chip into alignment.  Thus, the need to upgrade.

So, I knew this was going to be a bit of a stretch for the Quad QSA30.  Well, after just a little tuning, the FPGA is better than 90% accurate enough to require no touchhup.  But, all the other fine pitch parts were getting thrown all over the board.  I played around with the Z adjustments for the heads and for the individual component heights, but really wasn't fixing anything.  But, while watching the assembly, I could see some inductors being forcefully tossed around.
So, I began twiddling the setting for that part, but it didn't help.  Finally, I just told the machine to skip that part, and all the rest of the parts came out pretty good.  not perfect, still had to poke some of them, but WAY better.

Examining the board, I could see depressions in the solder paste that seemed to indicate the parts were initially placed properly, but then got moved.

So, I'm thinking that my solder paste is kaput.  It is way past the expiration date, but hasn't failed me until just now.
Those MSP10 pads don't have very much solder paste on them at all!

I'm going to try some water-soluble paste I have here that is much newer.  I'll have to wash the boards after, but that will tell whether the paste has lost its stickiness.

Jon

[Styno]

Examining the board, I could see depressions in the solder paste that seemed to indicate the parts were initially placed properly, but then got moved.

So, I'm thinking that my solder paste is kaput.  It is way past the expiration date, but hasn't failed me until just now.
Those MSP10 pads don't have very much solder paste on them at all!

So the part is basically sticking to the nozzle while the nozzle lifts again after placement? Possible causes:
- Blow-off isn't doing it's job. This might be an indication of a clogged nozzle, filter or sticky blow-off valve, or the regulator needs to give just a little more flow.
- The nozzle can be just dirty and sticky with solder paste.

Something else that could cause this:
- The placement height is too low and the board bounces back after placement, launching the part. This is an indication of bad machine calibration, nozzle length setting or wrong component height setting (most likely). I hear a loud *thunk* on each placement when something like this happens with our machine.

Were it not for the indentations then I would also check the camera recognition of the part location/rotation on the nozzle.

I use the slo-mo camera function of my phone to diagnose these sorts of problems.

I'm amazed that such a complex machine has difficulty with 0.5mm pitch components, let alone 0.65. Those are even placed accurately with our simple & old Dima Optimat.

[jmelson]

So the part is basically sticking to the nozzle while the nozzle lifts again after placement?

No, I don't think that is the problem, as NOT placing the inductors allows the fine pitch ICs to be placed accurately.

Something else that could cause this:
- The placement height is too low and the board bounces back after placement, launching the part. This is an indication of bad machine calibration, nozzle length setting or wrong component height setting (most likely). I hear a loud *thunk* on each placement when something like this happens with our machine.

Yes, this seems to be the problem, but I don't think the calibrations and settings are very wrong.  I did have some wrong settings a week ago, and I could easily see the board flex when that component is placed.  Also, if the inductor ended up end-on to the nozzle, it would then plunge too deep and go flying several feet!  (The alignment camera SHOULD have rejected the part in that case.)  Now, I cannot see any flex when the parts are placed, and it doesn't click either.

Were it not for the indentations then I would also check the camera recognition of the part location/rotation on the nozzle.

Again, when the inductors are skipped, the parts are placed quite accurately.  I think the paste is kaput, the fine pitch parts are not adhering to the board.  Also, when the board leaves the machine, the conveyor slams it into the exit stop pretty hard.  That's never been a problem before, but might contribute to parts moving.

I'm going to try different (newer) paste tomorrow.  It is water soluble, so I'll have to wash the boards after reflow.
But, it will verify if the paste is the cause of the issue.

I use the slo-mo camera function of my phone to diagnose these sorts of problems.

I'm amazed that such a complex machine has difficulty with 0.5mm pitch components, let alone 0.65. Those are even placed accurately with our simple & old Dima Optimat.

The head is so big, it covers the whole board.  The only way to see anything is to kneel down and look down the conveyor.  Not the best place to see what is happening.

I don't think the pitch is the problem, just that the paste apertures for the fine pitch parts are REALLY small, to avoid solder bridges.  So, that means the small, fine pitch parts have VERY LITTLE paste to hold the part in place.  The MSOP10 have just 10 TINY dots of paste to adhere them.  Any bounce or banging of the board will displace components.  And, if the paste has separated and most of the flux has already been used up, it won't be sticky enough to hole the parts.  I will find out soon.

Thanks for the comments,

Jon

[jmelson]

And more saga!  I was placing some boards, all was going well, then the machine started making HUGE banging noises, like a crash.
I was thinking maybe an encoder cable was going bad, so I tried to examine the issue by manually jogging around the area where it seemed to make the banging.  It would NOT jerk or bang when jogging, only when under control of the placement program.  Also, it would home smoothly.  So, I thought "maybe it is software".  So, I powered down and rebooted it, and the problem totally disappeared!  I made about 8 more of those boards just fine.  Kind of crazy stuff you run into on an old machine.

Jon

[jmelson]

Well, more saga!  I went to make another batch of boards I had made before, thought this is going to be simple, no programming needed.  I powered up the machine and it would not home.  I had had this problem before after not using the machine for a while, but the usual fixes didn't get it running.  Then, I went in the back and saw an error code on the Y axis servo amp.  I'd never checked this before when it wouldn't home, so I don't know if this was the issue in the past.
Anyway, I ordered a replacement servo amp from Korea, and put it in and it worked perfectly.  I was worried that I might need to get the servo tuning parameters out of the old amp, but the new one had smooth and quiet response and all coordinates seemed to be right on.
Jon

[jmelson]

Finally some good news.  I had not run the machine for a LONG time, due to really slow sales.  I am now running low on stuffed boards, so had to get going.  After the recent fix of a servo amp, I made 25 back sides of my resolver converter board, and it all ran fine.  I had to relearn a few things about running it.  The last hard to get part will come next tuesday, then I'll set up and run the front side.
Jon

[jmelson]

And, the saga continues!  I was setting up to run a batch of my servo amp boards.  When I fired the machine up, the X servo amp came up with the same symptoms as the Y amp did eariier this year, so I knew it would need to be replaced.  That fixed it.  The symptoms were violent banging moves rignt after startup, then some time later the amp would just not come up.  Anyway, I have now almost completed 50 of these boards (both sides).  And, I had an issue which had appeared before, where one specific part type would not be placed accurately, just tossed all over the board.
I could see perfectly-placed dents in the solder paste, so I knew the part was initially being properly placed, but it then must have stuck to the nozzle.   Now, the pattern became clear!  These parts were ones where I created a NEW part type, rather than just adding a new part to an existing part type.  I figured out there must be some menu that I was not filling out when creating a type.  "TYPE" refers to the most generic level, like "DIODE" or "SOIC".  So, All i had to do was look, and there was a button "Edit Mount Data".  This brings up a page that has all the vacuum/blow-off timings and Z motion speeds.  I had never even LOOKED at that page before!  I copied the settings from SOIC to the new type, and boom, it all worked perfectly!

Well, there was one more issue that I had seen before, a long time ago.  My workflow is to make sure all parts are entered in  the compoent library, then select all parts from the library to the parts list, then assign those parts to feeder locations.  Then, import the placement file with "CAD IMPORT" that puts it in a spreadsheet-like format, with designator (like R101, Q12) and XY coords, and part type (like 2N2222 or 74HC123).
Then, you run the "optimizer" that assigns nozzles to the parts and optimizes the order of placement to minimize motion time.  I had some small passives dropped on the board.  I found that 2 parts had been scrambled in the placement spreadsheet.  Instead of a part designator (R1 and R8) it had the same coordinate-like number 59.106 (which did not appear anywhere in the imported file) placed there.  The XY coordinates were not the same as anywhere in the imported file.  I had seen this sort of scrambling before, when I was first testing out the machine in late 2000.  It is POSSIBLE that I did this by bobbling the mouse keys, it is awfully easy to drag and drop a cell into the spreadsheet.  I will have to do more testing and carefully scan for botched designators in the future.

Oh, one other thing, I needed to place 27 different parts on this board/side, which is more that I have ever done before.  All those feeders would not fit on the front rail, so I had to use the back rail. There was no feeder power on the back rail, so I had to rig a power supply for that.  And, I assumed that you had to rotate the parts when picked from the back rail.  But, I discovered the software automatically rotates the parts 180 degrees for you, so you program the rotation AS IF they were on the front rail!  Cool!

Jon

[Mangozac]

And, I assumed that you had to rotate the parts when picked from the back rail.  But, I discovered the software automatically rotates the parts 180 degrees for you, so you program the rotation AS IF they were on the front rail!  Cool!

One of the frustrating aspects of the Chinese machines is that they don't have the ability to correct rotation for parts mounted on the rear.

[jmelson]

Well, what's worse?  Not having it automatically rotate the part, or not TELLING you it will do that for you?  I don't THINK this feature is in the manual, but then I have written before that the Quad/Samsung manuals are really quite bad!
Jon

[Mangozac]

That's true, but before we invested in SMT equipment I had just assumed the machine would automatically account for it. It seems a trivial thing for the machine to do and potentially saves a lot of headache.

[48X24X48X]

And, I assumed that you had to rotate the parts when picked from the back rail.  But, I discovered the software automatically rotates the parts 180 degrees for you, so you program the rotation AS IF they were on the front rail!  Cool!

One of the frustrating aspects of the Chinese machines is that they don't have the ability to correct rotation for parts mounted on the rear.

HWGC machine has this feature for the back feeder. I think the Kayo software is a bit behind in terms of feature compared to HWGC's in my opinion. But both boss did originate from the same company last time.

[jmelson]

Annnd, more saga!  I was assebling a batch of boards, and the first board went fine.  Then, all of a sudden, it started rejecting one part.  I had no idea what was going on, but a closer look at the error message indicated a bad size reading on the alignment camera.  I did a "test pick" on that part, and got crazy dimensions, like 19mm on a 7mm part.  I then ran the diagnostic on the alignment camera, and saw that there was a huge shadow at the right end of the image.  This machine has QuadAlign line-scan cameras that look across the part with a laser line source and a linear CCD camera chip.  The diagnostic give a screen that looks like a digital scope where horizontal is the line of pixels and vertical is the darkness of the shadow produced by the part.  I tried cleaning the camera in place with no improvement, then pullled the camera off and cleaned it with Q-tips and alcohol.  No better.  Then, I took it off again and did a much more vigorous cleaning of the illuminator side of the camera assembly, and it knocked the dark spot down enough that the machine would run.
2 weeks later (after some parts came in) I set up to do the front side of the board and decided to check the camera again.  The dark spot is TOTALLY gone!  I NEVER expected that!  Glad I didn't runs out and buy another camera from the brokers.  I have NO IDEA what caused the spot to totally disappear, although there WAS some particulate dirt in both the sensor side and the illuminator side of the camera.  But, I thought I got it ALL out of there in the last cleaning.

Well, keeping this machine running has been quite a saga, indeed.

Jon

[Kean]

2 weeks later (after some parts came in) I set up to do the front side of the board and decided to check the camera again.  The dark spot is TOTALLY gone!  I NEVER expected that!  Glad I didn't runs out and buy another camera from the brokers.  I have NO IDEA what caused the spot to totally disappear, although there WAS some particulate dirt in both the sensor side and the illuminator side of the camera.  But, I thought I got it ALL out of there in the last cleaning.

Maybe it was some moisture?

[jmelson]

2 weeks later (after some parts came in) I set up to do the front side of the board and decided to check the camera again.  The dark spot is TOTALLY gone!  I NEVER expected that!  Glad I didn't run out and buy another camera from the brokers.  I have NO IDEA what caused the spot to totally disappear, although there WAS some particulate dirt in both the sensor side and the illuminator side of the camera.  But, I thought I got it ALL out of there in the last cleaning.

Maybe it was some moisture?

Yes, possibly I didn't wait long enough for the alcohol drops to evaporate.  That seems lime a pretty good guess.
Jon

[jmelson]

Well, I had not run the machine in a long time.  Last weel I ran the back side of my resolver boards, went just great.  Zero pick errors for 32 boards with 22 components each (5 different types), total of 704 placements.  Then, this weekend I set up to do the front side.  All setup went fine, then fired up to do the actual placement.  The machine would not home, one of the rotation motors wasn't moving properly.  Trying to jog it manually, I saw that it rotated the wrong way when I pressed the button.  Well, obviously, the direction signal was not getting to the step driver.  I tried reseating connectors there, and then it wouldn't move at ALL!  I figured this had to be a connection issue, but swapped out the step driver, no change.  Finally, after ohming out the cables and finding no connectivity on that drive's inputs, I spotted what I'd done.  There is an interface board that feeds the differential drive to the step & dir inputs of the driver, and I had pulled on the connector enough to lift the header body up from the PC board enough so the pins didn't make contact.  I pushed the header body back flush to the board, and it all started workig again!  Yikes, I was thinking I might have a bad cable or board someplace that might be hard to diagnose.
So, got the batch of front sides all done yesterday.
Jon