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Lead free component VS vision on Mydata M12

Views: 1725

#37715

Lead free component VS vision on Mydata M12 | 8 November, 2005

I just received a reel of RoHS parts but I have a rejection rate of 15% since I started using it.Does anyone has experience this so far? My machine Mydata My12 with TPsys 2.2.5e

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#37717

Lead free component VS vision on Mydata M12 | 8 November, 2005

Are your rejections due to mechanical, electrical or hydra vision errors?

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Rob

#37733

Lead free component VS vision on Mydata M12 | 9 November, 2005

What is the manufacturers part No.?

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#37736

Lead free component VS vision on Mydata M12 | 9 November, 2005

Hi,

It sounds like your vision is not setup right for this component, and it's rejecting some of them because they would be failing the test.

This brings up a point we discovered. Don't use auto teach for the component if your using HYDRA or vision, as I think it's a totally flawed concept on any machine.

I think you cannot load a component that naturally varies in dimensions without manually entering the manufacturers data directly. However this auto teach thing is shown off a trade shows as a great thing, and on MYDATA machines its so easy to use, it used to setup component types.

But auto teaching one component won't help all the others you try and place which vary from component to component. Only the manufacturers data is correct, and even that needs to be widened a bit sometimes.

I think auto teach can never work. We had one component we had to re auto-teach every time we changed the reel, and another that varied in size down the reel, so it failed at a high percentage.

Anyway, that's my rant on this typic. What do others think of this theory. It solved all our problems when we stopped auto teaching. But that was also on a Fuji we did this, because we retired the MYDATA because of lack of accuracy in placement. We needed much higher.

So I would check the manufactures data for this component, and see if it's changed, and then check it's been entered.

Are you failing on the value check? Sometimes the electrical testing can be a problem, and you could even have worn test contacts with the component, and it's failing on the auto test.

You need to post the component type, and what kind of failure your getting as that will help.

Regards,

Grant

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smtspecialist

#37740

Lead free component VS vision on Mydata MY12 | 9 November, 2005

The part I'm having problem with is a simple 0805 resistor 0R the inspection is done optical not mechanical and 75% of the rejects rate has the message: one or too many bad leads found. and the other 25% the messages will give a Background or Contrast error number for the B and the C are playing anywhere between 100 and 5000.

I have the machine for three years and for 0805 I never had problem before. I was always using the 0805 package from the factory setting but in this case I am creating a special package 0805 for lead free. I tried so far to fixe this problem by increasing or decreasing the noise level and the contrast level in the F6 screen (optical) but with no luck!

It's impossible to say who is the manufacturer since my part supplier is a distributor and he remove all original label on the reel to stick his, all I can say is: made in Taiwan. According to my supplier, the part did not change in specs other then the platting for RoHS. My incoming inspection says dimensions are the same and I also measured it to see that the part are exactly as per specs, I also measured one of my part non-RoHS and they are identical. The only difference is really the platting when teaching the pick up position from the feeder I look at two 0805 sitting side by side, one RoHS and the other one non-RoHS, the difference is obvious. The RoHS part is doll VS the non-RoHS is shinny.

Thanks !

Red

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#37742

Lead free component VS vision on Mydata MY12 | 9 November, 2005

In TPSys 2.2, you do not have the Auto Teach function that Grant was talking about. The thing to do at this point is to include a MYDATA person. They have services which offer you to send your problematic part in and they will analyze it and tell you the solutions. This service is free. Or, you could always have a MYDATA technician come in and look at it as well.

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#37746

Lead free component VS vision on Mydata MY12 | 9 November, 2005

Sounds like the vision is having trouble deciphering what is the component and what is the background. The problem is what if the plating is inconsistent (sounds like it is)? In this case with front (reflective) lighting the problem may never be solved. If you get the 15% failures to pass then the other 85% will fail. This is why a backlit image is better. I wonder if this is a "sleeping giant" of a problem with lead free components and reflective type vision systems. Has anyone else experienced higher dropout rates with lead free components being processed on front lit vision systems? (Sorry, Red..I just responded to your question with more questions)

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smtspecialist

#37747

Lead free component VS vision on Mydata MY12 | 9 November, 2005

Thanks Avalancher. I had no clue about the fact that Mydata could analyze part for me. Since I'm in montreal it's hard and expensive to get a Mydata guy up here but sending the parts down there would be an great inexpensive solution. I've been over the phone with the Mydata techs regarding this but other then playing with the noise and contrast level they couldn't helped me that much!

Regards,

Red

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DannyJ

#37755

Lead free component VS vision on Mydata MY12 | 9 November, 2005

Hi Red and Greg,

First, to Avalancher, the service that is mentioned is fantastic. I have used it various times with various connectors and headers with fantastic results. Just contact MyData and they'll tell you what they need. It's usually 5-10 parts in the package they come in. Give them a week or two, you WILL get a response.

The vision on the 0805s, I can attest that it is due to the plating. I had a header yesterday that was giving me fits, since it only had leads on one side, and the plastic body was a glossy white. After reading all the literature on lighting, etc... they definitely work off of 'contrast', ie, reflective metal on a dark background. Since no lead parts are not as glossy as leaded, well, I can see where this may be an issue (we usually just mechanically center chips, but have a chip shooter, etc...).

Also, as Grant mentioned, the vision system does leave something to be desired. What you can change is in the autoteach feature, let it scan for the part and select your camera (geometric and vision). Then, in the second set of options, go to 'manual' and adjust your lighting as needed. This will control the LED array on the camera. Front light is directly underneath, ambient is 45 degrees and back is usually on the side. I have had great luck in adjusting these numbers, but takes a while to get used to.

Hope this helps.

Dan

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Rob

#37762

Lead free component VS vision on Mydata MY12 | 9 November, 2005

I don't want to throw a spanner in the works here, but a large proportion of chip resistors & capacitors have been ROHS compliant for a couple of years now, the manufacturers have just not declaired it.

Could it be that the part you have just has bad plating (this can happen quite often with "own brand" distributor resistors).

Our sister company is one of the biggest suppliers by volume of SMD resistors in Europe & we have not seen one issue like this (we do see it quite often when people use LEDs for the first time, so it does filter through).

Cheers,

Rob.

P.S. Moonman - This is what an absence of plugging looks like!

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A Total Green Planet Solution

#38031

Lead free component VS vision on Mydata M12 | 22 November, 2005

Try using a contrast filter. This seems to help. Also on the camera it self there is a white level control. Adjusting this may help. The bad thing is it may affect all your other profiles. Some times an easy fix is to have a screen print mark close to the part. Try marking your board next to the part until the part passes. Then screen-print a mark there. The vision recognition system needs a higher contracted area to compare against this may help and it is an easy fix without a huge amount of cost redoing profiles.

Mike Dolbow Component Engineering A Total Green Planet Solution www.atotalgps.com

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adlsmt

#38036

Lead free component VS vision on Mydata M12 | 22 November, 2005

Hmmm... that might work on some AOI machines but I believe the vision inspection is usually performed before the part is placed on the board, at least thats the way my machines work!!

Website was much more attractive than moonman's though!!

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