PCB pick and place machine and component wastage

Go To Last Post
8 posts / 0 new
Author
Message
#1
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hi All

 

Does anyone operate any pick and place machine, with some experience with various types of reels and average wastage in components to expect?

 

 

This topic has a solution.

Thanks

Regards

DJ

Last Edited: Fri. May 14, 2021 - 08:08 AM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Expect up to 10% waste.  That’s what my fab house quotes.  Of course they have a cheap machine, but they are 60% cheaper than my local place that also quotes 10% waste so do the math

 

jim

I would rather attempt something great and fail, than attempt nothing and succeed - Fortune Cookie

 

"The critical shortage here is not stuff, but time." - Johan Ekdahl

 

"Step N is required before you can do step N+1!" - ka7ehk

 

"If you want a career with a known path - become an undertaker. Dead people don't sue!" - Kartman

"Why is there a "Highway to Hell" and only a "Stairway to Heaven"? A prediction of the expected traffic load?"  - Lee "theusch"

 

Speak sweetly. It makes your words easier to digest when at a later date you have to eat them ;-)  - Source Unknown

Please Read: Code-of-Conduct

Atmel Studio6.2/AS7, DipTrace, Quartus, MPLAB, RSLogix user

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Does anyone operate any pick and place machine, with some experience with various types of reels and average wastage in components to expect?

That's one reason to use the same values on your board rather than using 10 different values...such as make all your resistors 5K & all caps 0.1uF  (to the extent possible).  So make that 33.1K pull down 5K.  Many times the exact value doesn't need to be exact.  We went through a design someone brought us & cut the number of differing "jelly bean" parts by at least 30%.  It also helps purchase pricing, since the remaining parts volume goes up.

 

Have you seen these extenders?

 

https://tapesplice.com/product-c...

When in the dark remember-the future looks brighter than ever.   I look forward to being able to predict the future!

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Yes, I agree, for example, if we have a 20K resistor, we aim to use 2 sets of 10K. This also keeps the BOM costing low. Therefore my new designs use as many common components as possible.

 

Yes, we use those extenders, when we purchase simple tape, not in reels.

 

A small company near me has a machine, which we use at very low cost, due to a personal friend. 

 

Today, we set the machine(takes a long timesad)to run a batch of 30 PCBs and found a lot of waste from a 220K 0603 reel, I would say this was about 15-20%. 

 

We discovered, that the pockets that the resistors are placed into in the tape, was too big, therefore at times if a good portion of the surface area of the component is not in the center, the nozzle can not pick it up. When we compared it to the other reels and pocket sizes, we noticed with others 70% of the component is always in the center.

 

 

 

 

 

 

Thanks

Regards

DJ

This reply has been marked as the solution. 
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

The SMD lines I have seen would not be pleased with a 30 unit run. It takes a lot of effort to sort things out (including what nozzle to use), which is all downtime. To gain back some utilization, they need to run thousands of units. If the tape is the problem, then the supply chain needs to be sorted, but I suspect it is nozzle selection. If you want to use your friends, SMD, then what are its capabilities. Maybe it has a tiny nozzle that can do 0402 and a mid-sized nozzle that can do 0805, but the 0603 is a problem; if that were the case, then do the layout with those limitations in mind.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Our machine has a zero waste system, but we designed the machine and it's vision system. And can easily run low volume to high volume, the sacrifice is speed. Our machine is focused on accuracy and low waste. Most commercial machines do waste at least 1 up to 10 percent and are focused primary on assembly speed, that is the mainstream, focusing on assembly speed, since most components are cheap. The rule of thumb is to quote 10% waste on a typical commercial machine that has been reasonably calibrated. Be warned many low cost china machines have abnormally high component waste, and vision placement accuraccy issues. I have noticed different component manufacturers will have different pocket sizes so if you need 0603 size you can probably try some different manufacturers in find one with a tighter pocket. If your design is able to accommodate 0805 those typically do have loose pockets but almost never out of centre so they will pick up fine on almost any machine, but whatever machine does pick them up will need to have a good alignment system such as a good vision system.

Last Edited: Sat. May 15, 2021 - 01:22 PM
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

12oclocker wrote:
manufacturers

 

Thanks Make sense

 

So you make your own machine for internal use or for selling as well?

Thanks

Regards

DJ

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

ron_sutherland wrote:
The SMD lines I have seen would not be pleased with a 30 unit run.
Some PCBA manufacturers do have a low quantity option (prototypes)

ron_sutherland wrote:
If the tape is the problem, ...
Some distributors create kits (BOM into a plastic bag); IIRC, some operators at PCBA manufacturers simply empty the bag onto a flat tray.

 


Electronics Manufacturing in North America - MacroFab

by Jake Prevelige  |  December 26, 2019

[mid-page]

Scaling from Prototypes to Production

...

In contrast, many North American CMs offer no minimum order quantities. This makes the process more affordable and manageable to implement design iterations and engineering testing of new changes. 

...

House Parts - MacroFab

 

"Dare to be naïve." - Buckminster Fuller