smd pick 'n place jig

[johnthedoctor]

Any interest in a jig that's better than using tweezers or a bit of coat hanger but not as complex (expensive) as the commercial pick and place machines?

I'm hoping that between us we can come up with a good design and get them built, maybe by a hobbiest model engineer. (I have no lathe or mill.)

Target price $50 or less.

Any ideas/interest?

[rpapps]

Have you seen the Australian movie "The Castle"?
It has an often quoted tag line which seems appropriate.
"Tell him he's dreaming".
Cheers
Rob

[dnsey]

A suction handler is perfectly good for DIY work. I got mine on eBay, with three different nozzles, for under GBP10.00.

[johnthedoctor]

Thanks dnsey, didn't know suitable suction handlers were available as one-offs.

Had a look on UK ebay for 'suction handle' but nothing current or completed except stuff for pulling dents or lifting glass sheets etc. Any chance of a pic of yours to let me know what I'm looking for?

rpapps, I'm not trying to build a robot for a quid, just hoping to get a bit more convenience in smd soldering for some collective thought and a little cash.

I messed about with an old drill stand attachment, the basic design might have possibilities: pick up component, raise, slide pcb under it, lower component and solder.

I assume the assembly factories have nozzles specifically for 0805 packages etc. No idea if those nozzles can be bought at a realistic price but I'm sure the guys building model steam engines are good enough to make ones to our design.

[dnsey]

This is the sort of thing.
(Not the supplier I bought mine from, so I can't vouch for him!)

[AndrewT]

Hi,
seeing that pic reminds me of a medical syringe.

Get an outsize needle and bend it around a former, then blunt it on some carbide paper.
Fit a spring inside the syringe to force the plunger out.
Fit a suction cup over the end of the bent needle.

Any better ideas?

[johnthedoctor]

That sounds workable.

Does the needle have to be bent? I'm still thinking on the lines of something vertical. Thin brass tubing could be the needle. Doesn't have to be a medical syringe, got a 150ml one here that's just for measuring. A small Calpol syringe, as used for teething babies, might also work, will have to test.

dnsey, is the vacuum good enough to stop the component moving while soldering? Half of those on my first smd attempt aren't straight.
Also, how does the rubber (?) seal stand up to the heat?

[rjkdivin]

I'm not sure the syringe with a spring concept will work very well. It seems to me you need a constant airflow 'vacuum' like from a pump in order to overcome leakage around the part being held. A syringe could only hold the part for a limited time unless the seal at the tip was very good.
Robert

[dnsey]

The cylinder is large in relation to the suction nozzles, so there's plenty of reserve to hold parts for several minutes (in fact I've never found the limit).
The nozzles are presumably silicone rubber - very flexible - and stand normal soldering temperatures without damage. There's inevitably a bit of movement due to the flexibility, but it's so easy to place components precisely that you don't need to 'nudge' them as with other methods, so they get soldered wherever you put them.

[rfbrw]

Originally posted by johnthedoctor
Any interest in a jig that's better than using tweezers or a bit of coat hanger but not as complex (expensive) as the commercial pick and place machines?

I'm hoping that between us we can come up with a good design and get them built, maybe by a hobbiest model engineer. (I have no lathe or mill.)

Target price $50 or less.

Any ideas/interest?

Not for $50 earth dollars. The fundamentals remain the same irrespective of the target market. The bed holding the pcb or the placement arm still has to be move with the same degree of accuracy. The control logic, the actuators and sensors will be no different from a commercial variant. You couldn't get the metalwork for $50.