Pick and place machine

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Just finished second run of boards on the new P&P machine.
First batch of boards hand quite diverse range of components from sot23 to surface mounted 2 mm pitch headers.
Had some problems with pickling up some melfs but that was based on machine seeking pick and place Z position based on vacuum sensing.
Manual adjustment improved reliability.
Second batch much lower diversity but higher count.

Timing shows 124 components placed in 4 min. 28 seconds with vision component alignment.

Piccies to follow, its a bit late of the evening.

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I bet it does P&P but what about the core of the problem, that is: feeders choice?
Are you able to place a decent component count project in a reasonable time, using low feeders count machine? Including the time for swapping feeders, rework, lost components etc?
34zyu

No RSTDISBL, no fun!

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Brutte ,

The questions are all well worth considering.
What is deemed decent component count and more importantly component diversity?
I think this was addressed after a fashion in the link in Your posting.
I am presently looking to set up bins ( literally pockets in a tray ) and place them in the free space ( akin to a JEDEC tray) adjacent to a feeder bank to dispense bulk components.
Candidates for this task could be low volume components releasing a feeder slot for high volume placement parts such as decoupling caps etc.

Software and vision system allow bulk bins to be defined and utilised in this fashion.
The feeders come in blocks containing anywhere from 8 to 16 feeders depending on feeder widths ( 2700 euro to 3600 euro )and are inserted and removed from the machine as a single module. So given a "library" of feeders the change over literally consists of loosening a locking/ locating screw and unplugging a single control cable to remove a feeder bank and conversely tightening a locking/locating screw and plugging in a control cable. In addition to bulk bins machine supports two ski slope feeder banks capable of feeding SO8 to PLCC68 components.

The placement sequence is presented as a list of components so that operator can select any one component and execute placement out of sequence.

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this is the semi assembled board.
It will carry a bunch of LEDS on the flip side.
The PCB is of the milled solder masked silver plated variety.

Attachment(s): 

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The paste was applied with milled stencil made from FR4 core material 0.2mm thick pinned to a bit of 1.6mm FR4 material with the opening to hold the PCB.
Paste applied with a putty knife.

Attachment(s): 

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So what's with all those holes?

The largest known prime number: 282589933-1

In my humble opinion, I'm always right. 

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That is the stencil.
The complete stencil consists of the base plate with an opening to hold the PCB and the top stencilsheet which contains openings for the solder paste pattern.
These two elements are pinned togother to ensure proper registration between the PCB and the solder paste pattern.

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Can you make a stencil using your milling machine for a fine pitch part such as a qfp with 0.5mm pitch?

If not, what is the limit?

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Looks like a great DIY project.

A number of years ago I visited a small company that did special assemblies, they had made a pick and place machine out of fisher technik, that was really fun to watch.

How does your machine look like?

regards

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No, I mean in your Photo0027.jpg. What's with all the holes?

I've tried a couple times to make a stencil from pop can aluminum. Broke the last one while I was trying to remove the etch resist. Haven't tried it in a while.

The largest known prime number: 282589933-1

In my humble opinion, I'm always right. 

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Chuck,

The stencil is made from 0.3mm double-sided fr4 core material ( core refers to the fact that this material is used to construct the core section of a multilayer lay up.
The limit on openings is determined by thickness of material and tool size.
I take stencil data flip it over and then mill it. The net outcome is that I end up with correct size openings in contact with the PCB but smaller openings through which the paste is squeegeed. Opening walls are inclined towards the product being stencilled resulting in a cleaner release of paste.
This shape due to the conical nature of the tool.
The smallest tool I have is capable of milling a 0.1mm isolation path in copper. I will have to see just how practical ( robust) a stencil with 0,5mm pitch features is produced.

Meslop,

The machine is a small bench-top affair with dual camera system and linear positional sensors with 5 micron resolution capable of processing 0201 components.
For a video of the machine ( in German ) http://www.youtube.com/watch?v=O...

Torby the PCB is a double sided ( components on both sides ) design. SMD components are used to select and control intensity of various coloured LEDS. LEDS are mounted from the other side ( PTH components) .
Part of a test bed to be built into an humidi crib ( hospital environment) to allow researchers to investigate effect of various lighting conditions on cellular cultures.

Torby,
this stencil is made from very thin double sided FR4 material.
Registration between stencil and product is ensured through the use of a couple of tooling pins to pin the stencil face to stencil base frame( another piece of FR4 1.6mm thick laminate).