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  • Author Author: rachaelp
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Lab Equipment Projects - Vacuum Pick and Place Assistant Part 1 - Overview

rachaelp

There's been a lot of talk on 's blog for his pick and place buddy recently and this gave me the motivation to get on with the very similar project I have been planning. There are some great ideas in that project and the subsequent discussions which will definitely enhance what I was planning and as a result of the inspiration from there have come up with a bunch of additional ideas for things I would like to add to my own. This will be the first blog of several as I go through the design and get it working. I have to fit this in around my main work so it may take a little while before it is complete.

 

The basic requirements for this project are as follows:

 

  1. Provide effective and controllable vacuum pickup for SMD components ranging from small surface mount passives to larger IC's.
  2. Give guidance to the user about which parts to place in which locations.
  3. Be reliable and easy to maintain.
  4. Be self contained (i.e. no need for external vacuum or compressed air source).
  5. Be relatively quiet in operation.
  6. Be integrated with my existing systems to ease use.

 

So today the chassis I ordered to complete the bulk of the kit needed for this project arrived. Whilst there are still things I need to add to the kit as I work through how it's all actually going to work, most of what I will need to get the initial prototype up and running are there. So here is a picture of the bulk of the items:

 

image

 

You can see I have gone for a substantial aluminium chassis. This is personal preference, I like equipment that has a really sturdy and well built feel to it so I went with a premium case. The down side is it makes sorting the mechanical parts of the project more challenging as cutting out holes in that thick brushed aluminium front panel is a lot more difficult than if it were a thin aluminium or plastic panel.

 

For the initial prototype I have got a cheap PSU from Amazon and I am using an Arduino for the simplicity of getting the thing working. Once it's all working I will probably spin a lot of the electronics into a custom PCB just so I can make it all neater and add in any customisations to the circuit that I want. I'll do a blog covering that process which will lead into some blogs I am considering covering EAGLE and how I set things up etc.

 

In the above you can see several pieces of the kit, some you'll know what they are for with regards a project of this type, others may be more of a mystery. I'm going to leave you guessing in the comments for a little while on that one just for a little fun image

 

This was just a brief overview, thanks for reading and let me know your thoughts in the comments!

Parents

  • I'm puzzled - I've been putting surface mount bits onto boards using the the same pair of stainless steel tweezers for the last 12 years. I can do 0.5mm pitch and 0603 easily (and 0402 at a pinch). I've never felt the need for a vacuum pick up (there is one on the soldering workstation but I never got on with it at all.)

    Where the vacuum pickup would help, perhaps, is when you need to solder 10 resistors of the same value to 4 boards, I used to ping all 40 onto the bench from the tape and of course some, (if you are really unlucky all) will be the wrong way up. If I picked slowly from the tape with a VP they would all come out the right way up.

    I solved this problem by tipping the parts onto a plastic lid (yogurt or cream, makes no difference), I can invert parts by tapping the lid with the tweezers - it's random of course but never takes long. The same technique works with SOT23 and even MSOPs.

     

    So, what am I missing, what does the vacuum pickup do extra ?

     

    MK

  • in reply to michaelkellett

    Vacuum pickup tools are faster and enable more consistently accurate placement in my experience. I've manually placed components with tweezers and as you start to get more parts on a board it soon becomes tiresome, it does for me at least. I find it's generally slower with tweezers as it takes time to sort the parts and pick them up and also I find that I can't place them as consistently as I would like and sometimes I drop the part or it's not sitting flat in my tweezers and I end up placing it on one end or on it's side and then have to try and nudge it back into place. It's not such a huge problem that every part is a struggle, but it happens enough to be an irritation.

     

    Your example of 4 boards with 10 of the same value is at the simple end of where the vacuum tool would help. I have boards here in my lab with hundreds of parts on and the thought of building them with just tweezers has been enough to put me off and cause those projects to grind to a halt....

  • in reply to rachaelp

    I think you must have had bad tweezersimage

    The 10 parts same value aren't the ONLY parts on the board:

     

    I did one earlier this year with about 500 components on the board - that does get tedious but I find that its the locating (on the board and in their little bags) and sorting of the parts that takes a long time.

    Putting down 50 or so 1uF decoupling caps is quick once you know where they go on the board.

     

    A pick and place machine would be fun but the programming time and need for zillions of reel feeders makes it a very marginal gain for the three to five prototype boards that is typical of what I do.

     

    MK

  • in reply to michaelkellett

    Michael Kellett wrote:

     

    I think you must have had bad tweezers

    That has definitely been an issue in the past, other careless engineers abusing the tips so they were misaligned or getting flux all over them and not cleaning them properly so they were sticky! I have my own decent set in my own lab now, but I think I have been mentally scarred by previous experiences so really don't like using them for large manual place jobs!

     

    Michael Kellett wrote:

     

    The 10 parts same value aren't the ONLY parts on the board:

     

    I did one earlier this year with about 500 components on the board - that does get tedious but I find that its the locating (on the board and in their little bags) and sorting of the parts that takes a long time.

    Putting down 50 or so 1uF decoupling caps is quick once you know where they go on the board.

     

    So if I am building a big board I will typically have all the small parts, R's, C's, Diodes, etc in strips of cut tape. I'll fix these down and peel back some of the covering tape. It's then really quick to pick these up out of the strips with the vacuum tool and as a result placing speed is significantly improved. If you are building batches of boards with 500 components on them then you'd probably save yourself a very significant amount of time if you used your vacuum tool.

     

    Michael Kellett wrote:

     

    A pick and place machine would be fun but the programming time and need for zillions of reel feeders makes it a very marginal gain for the three to five prototype boards that is typical of what I do.

     

    Possibly, but I think the programming time could be significantly reduced if you can get the info out of your CAD system in a useful format and find a way to automate some of the programming. In any case, a pick and place machine is just an awesome gadget to have in any lab!!! image

Comment
  • in reply to michaelkellett

    Michael Kellett wrote:

     

    I think you must have had bad tweezers

    That has definitely been an issue in the past, other careless engineers abusing the tips so they were misaligned or getting flux all over them and not cleaning them properly so they were sticky! I have my own decent set in my own lab now, but I think I have been mentally scarred by previous experiences so really don't like using them for large manual place jobs!

     

    Michael Kellett wrote:

     

    The 10 parts same value aren't the ONLY parts on the board:

     

    I did one earlier this year with about 500 components on the board - that does get tedious but I find that its the locating (on the board and in their little bags) and sorting of the parts that takes a long time.

    Putting down 50 or so 1uF decoupling caps is quick once you know where they go on the board.

     

    So if I am building a big board I will typically have all the small parts, R's, C's, Diodes, etc in strips of cut tape. I'll fix these down and peel back some of the covering tape. It's then really quick to pick these up out of the strips with the vacuum tool and as a result placing speed is significantly improved. If you are building batches of boards with 500 components on them then you'd probably save yourself a very significant amount of time if you used your vacuum tool.

     

    Michael Kellett wrote:

     

    A pick and place machine would be fun but the programming time and need for zillions of reel feeders makes it a very marginal gain for the three to five prototype boards that is typical of what I do.

     

    Possibly, but I think the programming time could be significantly reduced if you can get the info out of your CAD system in a useful format and find a way to automate some of the programming. In any case, a pick and place machine is just an awesome gadget to have in any lab!!! image

Children
  • in reply to rachaelp

    I too find it easier with vacuum than with tweezers.

     

    - as Rachael says, you can pick the components straight out of the strips.

    - it's possible to give the component an extra nudge down into the paste before releasing it, somewhat easier than with tweezers.

    - you can focus your hand movement on positioning alone. There's no additional agility needed to pinch the tweezers with just the right pressure (In particular the flat resistors manage to fly away with me, when I pinch a little too hard).

    - components can be a little closer too each other.

     

    on the other hand:

    - you're hindered by the air tube

    - more expensive, a reliable one costs money, a dodgy one gives frustration.

    - noisy

     

    On the other hand, you are certainly not the only one who prefers tweezers.