Custom pick and place nozzle, 3d print? Mill?

[loki42]

I have an issue with picking up a connector from hirose.  It's very long and very thin and doesn't have a cap or tape like some other connectors.  It has to mate with another part I don't control so can't easily change it. 

I'm thinking to try printing a nozzle. What material do people recommend? The stock nozzles are mostly polyurethane or stainless steel. 

I have drawings for them so customisation shouldn't be hard. If custom nozzle doesn't work I'll buy the grippers but they are pretty pricey. 

[Jackster]

Check to see if your machine has support for special heads that are made for this sort of thing.
The nozzle stepper has to be indexed for it to work but they make grip heads that are like two fingers that pick up odd parts.

[MR]

The nozzles from Mechatronika use a body from cheap soft iron and all they do is to insert a flat syringe needle, they can be bought cheaply.
For the 0201 Nozzles they used 2 syringe needles.0.7mm (od) 0.5mm (id), and inserted another needle there 0.5 (od) 0.3 (id).

For turning something like that I'd recommend to go and talk with a local company, especially a prototype could be done with a conventional mill (we have a few older guys around in town who still do that and their accuracy is pretty much okay)

Doing just a few parts is probably an overkill to outsource to china, the material is cheap and some hobbyists with decent machinery should be able to do that.
Lately I tried to make some cones with a DIY CNC lathe and it also worked out very well, it's not rocket science.

many years ago I outsourced making Mechatronika Nozzles (because they are just not worth their money, they charge like 100$ per Nozzle while the material is a cent article, turning 10 of them cost 90$ back then). Nowadays I'd probably also make them myself if I'd need them.

[loki42]

Check to see if your machine has support for special heads that are made for this sort of thing.
The nozzle stepper has to be indexed for it to work but they make grip heads that are like two fingers that pick up odd parts.

There's a bunch of custom nozzles from UIC and other vendors (Count on tools) for my Universal machines. They also have a range of gripper tools. https://www.uic.com/wp-content/uploads/2022/04/Master-Nozzle-Database_RevG.xlsx

I have 4 spindle, 7 spindle and 30 spindle machines. The 4 spindle looks the easiest to make custom nozzles for, UIC also provides examples.

The nozzle will need to be rectangular, a maybe 10-15mm by 1mm interior dimensions. UIC has nozzles similar to that in their custom nozzle database.

I've got a mill turn lathe but thought 3 d printing might have advantages for making flexible parts. I'm not sure if something with flex / rubbery would be better for making sure it gets a good seal. I can also get someone to print stainless.

[MR]

There are some youtubers from Australia with a small CNC lathe, you might try to reach out to them it should be fun for them and they'd have something to show off at youtube.

[loki42]

I've got a cnc mill turn lathe.  A nakamura tome.

[MR]

does it support G71/72 (or similar)? If so should be easy to do it yourself? If I really need I can have accuracies below 10µm with my cnc lathe it just needs a proper setup and some g-code which matches the performance of the machine.

[loki42]

My specific question is more about which specific 3d printable plastic I should try.  Nylon, abs, pla etc.  Happy to outsource printing to any fancy printer if required.

[law]

I've had good results with PCBway's 3d printing service. I've primarily used the UTR8220 plastic via the SLA service.
They claim +/-0.2mm tolerance for lengths under 100mm and from the parts I have they appear to be hitting this.
They have a DLP service that has +/-0.1mm tolerance for lengths under 100mm, but there seem to be less materials available for this. I haven't used this one.

I have found:
- Large flat surfaces can come out a bit wobbly. If I have a large surface that needs to sit flat against something else I now use three (or more) protrusions to act as the interfacing surfaces. There is less likelihood for them to be as wobbly as the large surface, and it is easier to machine/file/cut it down to size if I need too.
- UTR8220 is happy with threaded inserts. I've been gluing them in rather than heat pressing them in.
- UTR8220 is surprisingly tough. I'm using it in a demo hopping robot (see pictures) that has some reasonably large forces where the legs attach to the belt pulleys (via threaded inserts) and I haven't broken any yet.
- The parts are cheap and appear to be priced by part volume. So you can get many and select the best if you need good tolerances. Shipping does cost a bit though.
- The +/-0.2mm tolerance does hurt a bit in some occasions. I have an order in progress at the moment for a tray to hold C2220 size ceramic caps vertically for my pick and place. The features are small, so time will tell if I have success with this. That being said, I've had pulleys printed (pictures included) with GT2 belt teeth that worked straight from PCBway with no post processing.

Hope this helps

[law]

Hey,

Just an update on the vertical C2220 tray I mentioned in my previous post.
I just received the parts from pcbway and straight out of the box the work well.
I've included some pictures.
There are two parts; the first is a base that will be fixed to an aluminium plate on my pick and place.
The base has flexures printed directly into it that push the upper capacitor holding tray into some reference features (also directly printed).
This lets the tray be repeatedly positioned when I remove it to install more caps.
Anyway, this is not necessarily to promote a particular company, rather to show that SLA printing is pretty good.
Peace

[loki42]

Thanks for the info.  The price from them or jlcpcb to get it from stainless or tool steel is also very good.  I think I'll go for one of those as I can then surface grind the part if it's not flat enough so it'll be easy to get a good flat horizontal surface. 

[law]

Nice. I've had aluminium parts machined by pcbway and so far have no complaints.
Oh wait, I do have a complaint:
Make sure to call out / dimension / specify all features you care about on your drawing.
I had some heat plates made. I had a counter drilled hole (eg a deep counterbore) that was depicted in the drawing, but not called out in any way to say this is a counterdrill.
I assumed they would just drill the feature, as that is what it looks like and leave it, but instead of doing that, they milled the counterbore feature flat. (As in just dropped the milling cutter into the hole)
I then either had to change from a countersink screw to a button head screw or drill the features myself. I ended up drilling them myself.
I guess this is pretty standard MechE stuff, but I made a wrong assumption and had to do some extra work as a result.

[Doctorandus_P]

You can try if polycaprolactone works. (A.K.A Polymorph). It's a plastic very much like nylon. It's quite strong but melts at around 45 degrees celcius. (Just put some in hot water to melt it, take it out with a fork, and then you can kneed and mold it with your fingers because heat transfer is low)

1. Put a small blob on top of your connector.
2. Put a toothpick or other object though it (a straw mabye).
3. Put the nozzle of your PnP on top.
4. Let it cool down.
5. Clean it up a bit, make sure you have a proper hole for some vacuum.
6. Use it for a while.
7. Report back whether it works, a picture is also nice 

Polycaprolactone has it's limits. It has quite a lot of creep for example (which is expected for plastics used just under their melting point!).

[loki42]

Oh that's a great idea thanks!  I've modelled it up now so I'll see how 3d printing it in stainless steel works. I'll tidy it up on a surface grinder so I should be able to get it very flat and correctly sized. We'll see how it goes.  Luckily the shape of the il4 head nozzle is pretty easy.  The 7 spindle nozzles are a lot more complicated. 

[law]

If you don't mind, can you post a picture once you have it in stainless?
I'd be keen to see how it comes out!

[loki42]

I'll post the pictures and the files to make them.  I'm now also thinking I might make some custom nozzles for my selective soldering machine if these work well.