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I wonder if there may be some mileage in ramping the solenoid current using PWM to reduce the speed?

with proper acceleration and deceleration, you may be able to reduce motor current without missing steps, so the driver runs cooler.

This video shows the backing off idea for the pin.

https://www.youtube.com/watch?v=1AR7i8RnFxg

Hard to see from the vid, but I think you may be backing off a bit too much, risking hitting the back of the hole on a paper tape.

Only done it a couple of times, and I doubt I'd rely on it for production as it can be rather hit & miss.

It's a while since I've done it - I think some manual nudging after placement was needed, but not enough to be a disaster when I did a dozen or so of the pictured 32x32 LED boards

The issues I recall were calibration related rather than the actual part handling. Starting with a really clean & accurate paste print is  very important - with that a 50% mis-placement will still flow onto the pads.

Index idea.

Using SW8 is an interesting idea. If set, then an index command would increment that lane index count and the pin would flip up and down <indexcount> number of times to feedback instantly current set value. The pins can be pulsed quickly enough for it not to be annoying I think and that would provide instant feedback. It is a neat idea that does keep everything contained. Maybe SW8 when triggered would toggle all the pins to indicate you are in that mode. Then a timeout would be set for several minutes. Timeout reset upon receiving an indexing command. At the end the pins would do the toggle sequence again to indicate you have exited the mode. 

I think the easy answer is simply to have a pin "tick" every couple of seconds while SW8 is set, disabled for a 5 sec timout after the last index is set before it starts ticking again. I think that would be enough to remind you to unser SW8, but not so annoying if you need to walk away in the middle of setting up

I had another idea. For those with a laptop at hand, it is so quick to upload firmware with Arduino IDE. We could have a section at the top of the code file or a header file with defines in it and just re-flash the feeder to change settings.

Except when you've not used the machine for a month or two, you then have to dig out the laptop, remember how to do it all etc. For people not familiar with Arduino it's a big faff.

Wish I could find a silent vacuum pump. That noise really does start to wear on you after a few hours.

I've considered offboarding the pump and putting it in a soundproof box. Not sure if turn-on delay or flow rate might be an issue, obviously you'd want to keep the vacuum valve in the arm near the nozzle.

I am thinking of removing the dip switch panel and adding one of these usb panel mount cables. This will enable you to plug a usb cable into the board without having to dismantle the feeder. 

TBH I'd much rather have physical switches, as having to mess with USB connections, USB drivers  and other software can be a faff, especially as running USB-serial under Win98 might be a challenge.

How about this :
Location switches stay as normal
Set SW8, and send an index command from within RV place - this increments the index count for the selected lane 1,2,3,4 then back to 1
Instead of actually indexing, maybe just click the pin solenoid <n> times to indicate the number of indexes

This avoids the need for any other software or connection, uses the UI you'll already be using when setting feeders up, and only needs two DIP switch clicks to set up a whole feeder.

The only minor issue is if you forget to set SW8 back off afterwards, you don't want it to reprogram the indexes if you then run a job. Maybe have it click a pin periodically as a reminder, or have a timeout after setting SW8.

Anyone tried 0402 on an rv?

I've done 0402 LED matrices - pretty sure they were on 2mm tape - I think the "half index" option (by alternating pick position) works OK, and unlike the normal index counts, it's in the right place, i.e. the CDF and not the feeder def, so not as inconvenient to use.
Not sure how you'd even do half indexing sensibly within the feeder

Can't say I've had many issues with plastic tapes, apart from one occasion with some 0603 LEDs that came on really thin stuff that would bounce 50% of parts out as the tape advanced. Of course that was on a crazy-urgent job where I had to place about 10K of them... After a day of messing about with masking etc, I got it down to 10%, and fortunately Digikey had enough extra stock!
Those Trinamic drivers are pretty close to magic.
Something I'd definitely do if I were doing a new feeder board would be to manually select single/double feed, as it's a PITA having to do new feeder definitions if you have a mix of 4 & 8mm part pitches.

RV1 ( not 1S), no feeders, unrealistic price!  :
https://www.ebay.co.uk/itm/194207452253
RV4s working with feeders :
https://www.ebay.co.uk/itm/203500382837

There are a few odd lists of pinouts but no schematics.
There isn't anything particularly complicated, apart from the geometry of the arm of course!

Wider feeders are pretty rare. If you have access to a milling machine ( or pillar drill at a pinch), you can cut some of the dividers out to create wider lanes

No.

What I do with trays is stick an empty one onto the base with double sided tape, then place a second tray on top - as they lock together, the alignment is good when replacing a tray. 
No need to make a jig - the tray is the jig!

I think an OpenPnp port would be a massive job - apart from the peculiarities of the Scara geometry itself, you also have to deal with the situations where a move needs to be split into multiple moves as there are reachable positions that can't be moved between in a straight line.
Can Openpnp even deal with a non-rectangular working area?
Then you have to deal with the fact that the relationship between the fid cam and nozzle is different at different locations.
And figure out how to manage all the grid calibration stuff.
And figure out the maximum reliable speeds and timings for the various permutations of moves
And the tool loading sequences.
What would be the actual benefit ? The machine isn't going to end up any more accurate or faster.

Although the current software has its quirks and annoyances, none are show-stopping- I don't recall ever having any software issues which have resulted in ruined boards or significant lost parts, for example.

 

You did set "lock feeders" didn't you...?

And you've hooked the video capture commands in the RVS software in order to capture video using a modern camera over USB. You've rigged up a mount for that in place of the stock one?

No - using a composite video to USB capture device with the original cameras.

Are you still using COM ports on your PC to drive the feeders etc or do you have one of the set-ups where the COM ports are on the ISA card?

I'd be surprised if the COM ports didn't work via standard USB-serial converters, the only issue I can see is you may need to be able to force them to be low COM port numbers - this is usually just a case of fiddling with driver configuration.