DIY Pick and Place Machine project.

Low cost DIY SMD assembly machine.

A Pick and Place machine is essential for medium to large scale assembly of printed circuit boards. Unfortunately such
machines are often too expensive for small design and manufacturing firms to obtain. The following information is a
description of our efforts to build a bare bones and budget priced DIY Pick and Place machine.

This is an ongoing project featuring our initial efforts, and new currently evolving machine. It is our hope that some
visitors will find this information and down loadable content useful to their own efforts. Suggestions and ideas from the
public are welcome.

Version 1 DIY Pick and place machine.

This project was begun in mid 2016 and built using basic off the shelf automation components, hand made
fixtures, and cobbled together custom electronics. Its ugly, works haphazardly , and needs a lot of future work.
This web page will evolve as further re-designs are made.

It was decided to start with a bare bones system. Simple 0805 component loading without vision system
assisted correction. Generally SMD components do not need exact placement as components will often
auto-align themselves during the solder paste reflow process.

The key element to this system are.

1. A simple X, Y, and Z motion system required to move a vacuum pick-up head from the taped components
to the PCB being assembled.
2. A feeder system for advancing the component tapes and removing the covering plastic strip
holding components secure.
3. A vacuum pump and associated tubing.
4. Motor drive system and associated electronics.
5. PC application software to allow over all control of the entire assembly process.

The X,Y,Z motion system.
There isn't much to say about an X,Y,Z motion system. You've seen one, you've seen them all.
We started off with this basic arrangement.

Initial XYZ system for DIY pick and place machine

The Y axis (top to bottom) consists of 2x 8mm hardened shafts unsupported of length 762mm.
The X axis (left to right) initially consisted of 2x 8mm hardened shafts unsupported of length 495mm but it was
soon found that 2 unsupported rods left to much "wobble" in the moving head. Eventually we changed the X axis
to V-slot extrusion.

extrusion on X axis of Pick and Place machine

The Feeder system.
The component feeder system was and remains the most difficult aspect of a DIY pick and place machine. The key
attributes of a low cost DIY feeder system is that they are required to be as narrow as possible, and as cheap as
possible.
As more feeder units are added to the system the distance the pick head needs to move increases. The longer the
travel the more time is wasted picking a part, thus reducing overall production speed. In addition multiple feeders
will be required for a complete machine which makes individual cost critical as the cost will be multiplied by the
number of feeders added.
To reduce cost we decided to have the pick head draw the tape along, while a single geared motor rotated a bank of
constant friction pulleys for cover tape removal.

Element 1. The tape channel.
In order to guide the tape in its travel we simply milled out 8mm channels into plastic and left a groove for the
components inlaid to travel freely. We created these channels as sets of 5 grooves each. Once the initial set was
made we set it in silicon molding material and used the mold to create more with resin plastic. At this time
a 3D printer was not available which in hindsight would have made the entire process easier.
Element 2. The tape puller pin.
The pick head motor is the main force advancing the tape. In order to do that a pin is required to extend down
and insert into the tape registration holes. Originally it was thought that a solenoid would suffice but it became
too dificult to locate a solenoid with long enough reach. As usual we at Priority 1 Design improvised. We used
a simple 6V dc motor powered from a 2 volt source and simply swung a long thin rod into position when required.
A simple metal stop (screw) was used to prevent the motor from rotating freely and the rod kept in position using
stall torque.
When the motor is de-energised the rod swings back out of the way due to a weighted counter-balance.
Element 3. Cover tape removal.
Once the tape is advanced the plastic covering holding the component in place needs to be removed.

We also stock: