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Messages - SteveW

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1
RV Hardware / Re: RV1s Modernisation
« on: January 02, 2017, 01:13:41 PM »
Good stuff! Something I've pondered in the past, before just leaving well alone and making boards...
As Mike says, Win98 is probably worthwhile, for better networking and USB, and just generally being a bit less crappy. 

Apart from longer permissible part names, the only improvement I really hanker for is better vision. Maybe teaching from a known-good part, rather than dicking about with shapes in CDFs. The software, while it feels like a weird swamp when you first fire it up, is quite a good match for the hardware - good enough, needs care not to fall into traps.

That said, if there was an OpenPnP flow for the machine, I suspect I'd be on it like a shot.

2
RV Software / Re: Making CDFs
« on: August 16, 2016, 09:34:26 PM »
CDF -> Edit CDF Files -> Edit Body -> Edit Shape -> Edit Body -> choice of light & dark.


3
RV Software / Re: Making CDFs
« on: August 16, 2016, 07:24:05 PM »
Body is already set to light coloured (as in that first screenshot).
Naturally, it all just worked fine today!

Slightly odd, though, were these 0402s on interposer boards, which were tall enough and pale enough on the bottom to cause some mis-picks.
Those have to be the smallest PCBs out there!
No mention of anything weird on the reel...

Edit: Ah, it's a noise thing...
http://www.murata.com/en-global/about/newsroom/news/product/capacitor/2014/0626


Steve

4
RV Software / Re: Making CDFs
« on: August 15, 2016, 03:19:55 PM »
Ah, that's quite possible - I wonder if I told it it was gullwing, since it half is, and it's miffed about the belly pad.
Off to build another test panel, so thanks!

(My current nemesis is the USB-C sockets. A combination of buried uninspectable SMT pads on 0.5mm pitch,  0.16mm pins in 0.4mm diameter holes, and an annoying tendency to float on a layer of flux. Can't add much more paste without risking unfixable shorts, might resort to balancing pennies on top of them to press them down a bit during reflow...)
Hand fitted, naturally - Sorry, RV1S, you'd just mash the pins into the PCB.

5
RV Software / Re: Fiducial camera weirdness
« on: August 09, 2016, 08:06:07 PM »
PCB is one option, but may be tricky to get uniform lighting across the whole area. Also PCB doesn't have optimal contrast.

But PCB might be consistent with actual PCBs. Something with massive contrast and backlit may deliver crisper pics, but not line up with where the fiducials appear to be in real use / real lighting ?


6
RV Software / Re: Making CDFs
« on: August 09, 2016, 05:43:24 PM »
That's only seeing the leads. Powermite has a metal bottom. Quite a nice package thermally.
(On reckon you can dump 3W into one , but that seems like it'd need a lot of board! Anyway, I'm using a Schottky, with no real power concerns)
http://www.onsemi.com/pub_link/Collateral/1PMT5920B-D.PDF

I'd already diddled the body size and lead lengths to match the vision reported numbers - which is why I was particularly surprised to still be told the device was too big. Gave up and turned off 'use shape' - but I'd still like to know what I'm missing...



7
RV Software / Making CDFs
« on: August 09, 2016, 02:59:05 PM »
I'm slowly starting to get more adventurous with CDFs - normally I just hand place the tricky stuff, but I've got to make a few hundred of a board with a few tricky parts...
Some are going OK, but I'm stuck on this powermite diode. CDF looks sane, camera shot looks sane, x & y numbers match OK. However, Comp too big. What am I missing?

Cheers for any hints!

8
RV Software / Re: Fiducial camera weirdness
« on: August 09, 2016, 02:46:47 PM »
It does need someone to make the effort to build the calibration jig etc.  but at the moment, I can live with the way it works.

Is that just a PCB with a load of fiducials on it, from our favourite Chinese PCB house?
I'm happy to do that, if there are a few others to help soak up the postage...

9
RV Software / Re: RV4S windows 95 upgrade to windows 98
« on: May 30, 2016, 11:54:10 AM »
Try this:
https://dl.dropboxusercontent.com/u/19878973/Versatronics_Python.zip
Unpack it, and, if you want an easy life, SUBST (or NET USE, or whatever) yourself a P: Drive if on Windows) so the paths work.
READ_ME_ASSEMBLY.txt contains the instructions I follow (it's rigged to allow you to copy & paste from it into the cmd/powershell box. I tried to script it, but there's not really a lot of benefit, I often want to check things, or fix errors, as I go.

It's clearly not an external tool, and expresses its displeasure by crashing out rather than printing pretty error boxes. There are debug printfs all over the place to assist me, but possibly not you. Anyway, knock yourself out - use it, modify it, ignore it, just don't sue me! I've pushed hundreds of jobs through it, it fundamentally works.

Steve



10
General SMT / Re: Source of dispensing solderpaste?
« on: May 20, 2016, 10:22:58 PM »
Straight flux is a lot* easier than solder paste, though - there's none of the pain as the flux is squeezed out leaving a pellet of compressed solder balls.

I've started looking at 3D printer nozzles instead of dispensing needles. Still metal, and nicely controlled tapers. They also let me stop messing about with the spacer foot and shims, and just file or mill the standoff into the nozzle.
This sort of thing
http://www.aliexpress.com/item/10pcs-lot-3D-Printer-Nozzle-Mixed-Sizes-0-2mm-0-3mm-0-4mm-0-5mm-Print/32246531754.html
Next step is to try to use a (decent) twist drill as the pump - I've got the makings but not the time yet.

* orders of magnitude. Flux is what I use to purge mine when it's being a dick (more truthfully, when I don't have the  temperature high and equalised, but even then, some days, it just won't run right for long. Coming back the next day fixes it, no amount of messing about changing things does).



11
RV Software / Re: RV4S windows 95 upgrade to windows 98
« on: May 20, 2016, 10:07:21 PM »
Your fatal flaw is using the pick&place output from Altium, you should be exporting a (PCB, not schematic or project) BOM with X & Y locations - you can pick any attributes you like, in any order.

I've got some Python scripts that I use instead of Mike's VB, which also allows me to substitute my long Altium names with ones short enough not to make RVSeatup act like a mad thing when fields overflow (16 characters, if I recall).

I'll happily share them (and the instruction sheet, as you still need to mess with some control files) - it takes machine setup for a typical job down to about 5 minutes, and also generates dot maps for solder printing.

Steve



12
For Sale/Wanted, Suppliers / Re: Cheap(ish) vapour phase unit
« on: March 15, 2016, 04:16:15 PM »
Interesting - not as tall as I'd like, meaning vapour's got an easy path to escape or condense inconveniently. If it's really losing over a cc of fluid per run, the floor's going to get hellish slippery!
Still tempted, but my lashup seems to work pretty nicely.

13
General SMT / Re: Source of dispensing solderpaste?
« on: February 24, 2016, 07:02:39 PM »
Interesting - pity they're only available in tens though.
Looks like  these wouldn't be too hard to use as the basis of a DIY system. 

Singles here...
http://www.dosieren.de/en/products/cat/ersatzspindeln.html

14
RV Software / Re: Random rotations?
« on: January 24, 2016, 10:38:01 PM »
Yeah, that might do it - I wasn't watching it by the end (everything was going so well), so a bit of unlucky tape bounce could do it.
I thought that SOT23s drew a triangle around the shape during vision - but I can well believe it then turns that into a square and bangs it down regardless...
Strange that it was adjacent parts - but I'll shelve my paranoia for a while!

15
RV Software / Random rotations?
« on: January 24, 2016, 08:22:13 PM »
It's been a long and mostly successful day of placement - many boards, many thousands of parts.
Final board of the day, and the RV1S pulls this - two parts off by 180 degrees. Physically near each other, placed at very different times.

They went down straight, just off by 180 degrees. The other 4 channels of this on the same board went OK, and the other 5 of these boards went OK.

So - WTF? Did it just have a bit of a moment? Should I worry much? Fortunately, these are easy enough to spot, but if it's going to make a habit of this sort of thing...
I've had a few (maybe 5 in total) of the 'I can't be bothered to turn the vacuum pump on' component mis-picks today, which I think is more than average, but doesn't feel very related.
Anyone else seen similar weirdness? I thought I was running out of ways to be surprised by this machine.

Also, are there any cheap ways to AOI?

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