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Auto stencil printer or AOI

Views: 4917

#66324

Auto stencil printer or AOI | 11 May, 2012

Hi Guys, I need some help. I was running prototyping volume previous and my SMT line uses manual printing. Business has picked up and i started to get higher volume 300 to 500 pcs each model. I am running a small firm and have only a small sum of cash to only allow me to purchase either a auto printer or an AOI. Which one should i purchase? Manual printing of fine pitch ICs are giving me a lot of problems and manual inspection of assemblies is not reliable.

Thanks

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#66325

Auto stencil printer or AOI | 11 May, 2012

I personally believe that you money is best spent on improving your process. An automated printer will help make your process more repeatable, thus easier to control. An AOI will not improve your quality, it will only make your defects easier to detect. First spend your money on eliminating defects, then concentrate on inspection. Always remember, you can't inspect quality into your product.

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#66328

Auto stencil printer or AOI | 12 May, 2012

Hi thanks for your advice. Between, i do have quite a bit of THT PCBAs. How do you guys improve the productivity of manual inserting?

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#66343

Auto stencil printer or AOI | 15 May, 2012

Dittos from A Very Frazzled Man. Money spent on a better process is almost always more advantageous than better inspection.

As for manual TH insertion, have you considered a semi-automatic machine like the Contact Systems CS-400? While the "E" series machines are much more in demand and user friendly, you might consider an older "C" or "D" machine. You might be able to find one for a few thousand. We have a "C" and it works fine for us. See link below:

http://www.contactsystems.com/pdfs/brochure_cs400e.pdf

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#66346

Auto stencil printer or AOI | 15 May, 2012

Hi Before I say anything I ll qualify who I am. I work for a AOI/SPI manuafacturer

Automatic printer is your best option for small runs. Print process is responsible for a vast number of solder defects and improving here is your best start. Have a look at AOI later. Also vitally important to select the right stencil type for your process and correct blade length dont just try to stick with one for all your boards the best compromise is to have at least 3 sizes which should cover small medium and large board sizes.

Jeremy

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#66347

Auto stencil printer or AOI | 16 May, 2012

> Hi Before I say anything I ll qualify who I am. I > work for a AOI/SPI manuafacturer > > Automatic > printer is your best option for small > runs. Print process is responsible for a vast > number of solder defects and improving here is > your best start. Have a look at AOI later. Also > vitally important to select the right stencil > type for your process and correct blade length > dont just try to stick with one for all your > boards the best compromise is to have at least 3 > sizes which should cover small medium and large > board sizes. > > Jeremy

Hi Jeremy, i do agree with you. I am looking at older machines like Dek 265GSX. Any advices?

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#66348

Auto stencil printer or AOI | 16 May, 2012

Hi DeanM, is the programming difficult?

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#66349

Auto stencil printer or AOI | 16 May, 2012

In my experience Both Dek and speeline machines are good used. personally I think speedline seem to hold up better when PMs have been ignored though. Also make sure you can get a third party board support system into it like a gridlock or Vacunest as solid supports typically dont do as good a job.

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#66352

Auto stencil printer or AOI | 16 May, 2012

CS-400C: As with anything, once you are up on the learning curve its really not that bad. The "E" machines should be easier due to the touchscreen and the floppies are PC compatible unlike the "C" and "D". There are third party software providers that make it easier and can be done on your PC instead of on the machine (make sure the CS-400 has a serial port) but it is expensive (more than the machine). Only the "E" models are supported by the company but you can still get service and parts from other service providers for C/D.

For prototype work its not worth it, but for runs of several hundred, there should be a definite payback. What's nice is that the right part gets put into the right place due to the guide lights and the rotary parts bin where only one part is accessible at a time, so placement errors will go down. Also there is no more lead trimming. Here a some links to machines in operation:

http://www.youtube.com/watch?v=ym4EWTbEf1I

http://www.youtube.com/watch?v=BG8-PGlaPoo

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#66447

Auto stencil printer or AOI | 24 May, 2012

While buying a used printer may seem like a good value up front, you may be taking risks and making unnecessary compromises that will cost more in the long haul. The perceived cost savings of a used machine may quickly dissolve when you consider some of the other factors Has the machine been regularly maintained to OEM guidelines? Are any required calibration tools available? Is the software current? (Windows 95/NT?) Do you need to hire the OEM for service work or training? Are there registration fees to obtain support from the OEM? How long will the OEM support the machine, in some cases they may be your only avenue for spare parts. You should also give thought to how many years of reliable operation you can expect from a used machine. In most cases information on service and production history is difficult to come by. It’s what you don’t know that will cost you. When you add this up you may find a new machine makes more sense. You can expect many years of reliable operation from a new machine and you’ll be using current technology. There's no need to wonder if PMs were carried out correctly or if they were ever done in the first place.

I have been working with printers for nearly 20 years and while I may have a bias, I recommend you consider the Speedprint SP700 printer. You can get a new, fully automatic printer standard with all the process controls required to achieve a reliable, repeatable printing process for not much more than you will spend to get any decent used printer. You’ll also have a multi-year warranty and peace of mind knowing you won’t be caught with unexpected costs often associated with used equipment. Please see the banner ad in this forum.

Mark Brawley Vice President, Speedprint Technology mark.brawley@speedprint-tech.com www.speedprint-tech.com

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#66452

Auto stencil printer or AOI | 27 May, 2012

Seeing as you say you only have a small amount of cash ... I'd also consider a semi-auto printer where you align a golden board, set up the two cameras by boxing or overlaying a pad etc, and then use the vernier adjustment to get each pcb to align with your golden image. Something along the lines of an SMTech 100 MV. Not as fast as fully auto but these styles of machines will print just as accurately as a fully auto machine with the correct set up and operator interaction. Also very versatile in that you are not locked into the conveyor system which can be a problem with auto machines and customer supplied stencils.

You should be able to pick up a low mileage one of these machines for less than an auto. Stay away from clamshell type machines though. I have 5 fully auto machines and I keep the semi-auto as a spare. It has saved my bacon many times and I'd never part with it.

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