Messages

Here's a straight version, for when the PCB is hanging over the edge of the base. Uses the retainer from the corner block .zip above

Not sure what you mean by "doesn't do rotation or movement" that - both cameras measure offset and rotation to provide a correction for the placement position.
After doing the camera centre adjust, this should calibrate the camera positions relative to the nozzle, and placement should then be the same regardless of camera used.
There may be some threshold differences between cameras, but not placement offsets.

As mentioned above, after doing the upgrade I noticed some offsets between fixed and OTF, but these went away when I did the centre adjust - don't recall if I only did just the OTF, or both.

Just going on first principles, once calibrated, both cams should be aligned to "true" centres and no offset should be needed in the CDF.
It could be there are some oddities in the software ( or maybe a bent nozzle shaft), but I've never had any need to do any manual offsetting, apart from the occasional pick offset on asymmetrical components

Managed the white led OTF upgrade. Seems to be doing the trick. Took a bit of calibration and a placement offset adjustment in the cdf file but placed great after that. Real speed improvement to be able to use OTF reliably.

Assuming you removed the mirror, did you do the camera centre adjust as mentioned above?
Changing illuminator shouldn't need a placement offset adjust, only the brightness threshold.

I found that roughing up didn't make a big difference, also tried putting a small o-ring round the reel, but also didn't do much, though may be worth trying different sizes as I only used what I had to hand.

First run of this was a big success - absolutely no lazy pull-off issues at all, compared to typically 3 or 4 feeders in a bank having slip problems before.
Time will tell if there are any long-term issues with wear or belt tension.
I notice that the belts have quite a lot of residual tension after a few feeds, so as I don't use the machine much I'll try to remember to release the tension after a job.
 

Yes, 12V - it does dip a bit when the vacuum pump is on, but that's not an issue as it's always on when you need vision, so consistent.

OK these first versions are a bit of a fail :
Handle on cover retainer is too high - clashes with edge of nozzle.
Magnets cause tombstoning of some parts - need to increase height, maybe add provision for washer etc. for shielding
Low height also makes them more tedious to set up.
Will re-do at some point....

 

Passive tape holders.
30 x 4mm long ( limit of passive feeder length in RV software)
Tape retained by friction-fit bar ( left of image)
Has bumps at side and edns to help stacking.
Takes 5 dia x 3 high neodymium magnet-  press fit but suggest putting a drop of cyanoacrylate glue from the top to secure- make sure magnet is completely flush.
As-is, the fixing to the base plate is a bit slippery, so I added cavities on the underside to take some soft feet
https://www.rapidonline.com/r-tech-310000-pu-round-protective-feet-6-4-x-1-9-clear-sheet-255-31-0000
You could maybe make something similar in TPU. 

The wide ones could probably do with being longer & deeper for taller parts - I'll probably do these as & when needed, as Tinkercad was getting annoyingly slow with all variants in one design
Tinkercad link https://www.tinkercad.com/things/6ix3NnzxHmA

Zip of STLs below

tapeholders.zip

3D printed PCB corner block.
Print the base and two of the screw STLs.
Screws are held in place with M3x16 screw, washer and spring ( approx 8 dia x 10mm long)
Takes two 10mm dia x 5mm high Neodumium magnets

Having just got a 3D printer, I thought I'd have a go at improving the problem I'm always having of the belts on the cover-tape spools slipping, leading to inadequate peel.

I've done a design which adds knobbly bits to the belt part of the reel, and this definitely has better grip ( tested by passing a belt over this and a normal reel and seeing which slips first).

Not tested in anger yet - printing a couple of feeders' worth of them now. Could be that it's too grippy, but sharing files here in case anyone else wants to give it a go.

Tinkercad link to model : https://www.tinkercad.com/things/lPaYhVs57R6
STL files attached

https://www.ebay.co.uk/itm/385511312415

Before rewiring I'd try changing all the connectors in the path to that motor - IMO a connector is a more likely issue than a wire.
Start with big D-sub at the bottom ( I've had a pin fail & burn on this), and any of the IDC 0.1" header connectors - I've had these fail in feeders and have also replaced all the ones that connect to the stepper driver boards.

For diagnosis, as the stepper coils will have a pretty low resistance, doing a resistance measurement at the stepper control board while wiggling everything may be a way to find a bad connector.

If you have access to a thermal camera, might be worth a look around to see if you have any hotspots on connectors and cabling, which would probably be visible when not moving, as there will still be significant current in the stepper coils.

Mike, how is the OTF camera performing with the white led upgrade?

Huge improvement - almost never need to tweak thresholds now, and pretty much unaffected by all but direct sunlight.

Just finished a large-ish job with twenty 8mm lanes and no slips at all - roughing up the pulleys has shown a definite improvement over previous performance.