Everybody are talking about and we does not know the equipment and more details about. O. Tarango, please be specific in your problem description. They can be a pretty simple solution. (I hope so... )

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gregp

#32711

SMT component mis-aligned | 17 February, 2005

I would first check the alignment of the flux capacitor to the roto pluker mechanism.

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OverTheHill

#32717

SMT component mis-aligned | 17 February, 2005

Ah,ha,ha,ha,ha,ha.....Ah,ha,ha,ha

You guys are killing me !!!!!!!!!!!

Let's get serious folks.

O. Tarango, Tarango, Tarango. Every once in a while the earth has been known to wobble on it's axis. You were probably trying to build a board during that rare event.

That'll learn ya.........

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Dilbert

#32720

SMT component mis-aligned | 17 February, 2005

There were problems with the flux capacitors at my prevous job....the electrical guy kept pointing it out and the Hungarian mechanical guy would say "Umph, this is bad, very, very bad!".

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bobpan

#32727

SMT component mis-aligned | 18 February, 2005

rotate the machine 5 degrees and the placements will be dead nuts!!!!!!!

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Mark

#32728

SMT component mis-aligned | 18 February, 2005

This is brutal. O.Tarango, I think the techs on this forum need a bit more detail from you. There are only a million or so possibilities why your components are being mis-aligned.

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Paul pmd

#32748

SMT component mis-aligned | 18 February, 2005

I�m surprised how un professional the so-called experts can be. After all we all had our start sometime and if you can never remember asking a un qualified question in your entire career then you probably have a bad memory. This is an open forum for solutions to problems people have, by people who are suppose to know what they are doing. Making sarcastic comments at the expense of somebody�s feelings is wrong and just un-professional.

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Sr. Tech

#32763

SMT component mis-aligned | 21 February, 2005

Paul,

Since you are clearly a professional why don't you offer O.Tarango a solution ?

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Ordie

#32765

SMT component mis-aligned | 21 February, 2005

Gee Paul, the first two responses to this post where people fishing for info. I would love to help out on this one, but we all have nothing to work with. Can't troubleshoot without knowing the problem. Please feel free to write a 30 page solution about all the possible causes based on the very detailed original question. This is like fishing with no bait.

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Ordie

#32766

SMT component mis-aligned | 21 February, 2005

There are so many variables to this. It could be paste, pad size, contaminated components-pads, placement speed, component thickness being wrong in the program, dropping parts into the paste instead of placing them, component recognition ploblems. Is it before or after re-flow? Throw us a bone on this one?

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RDR

#32773

SMT component mis-aligned | 21 February, 2005

whatever happened to O'tarango anyway?

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Dougs

#32774

SMT component mis-aligned | 21 February, 2005

i think O.Tarango is still looking for the flux capacitors

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OverTheHill

#32777

SMT component mis-aligned | 21 February, 2005

O. Tarango = Troll

Paul pmd = O. Tarango

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O.Tarango

#32784

SMT component mis-aligned | 21 February, 2005

Firstable, thanks for all your comments,sorry if my question was too un detailed, I really need your help on this, actually we are using a 4796 HSP in our SMT process most of the incidences of mis aligned component are on two 0420's capacitors

Regards to all!

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pd not cruel

#32785

SMT component mis-aligned | 21 February, 2005

The solution to his problem, is clearly to get further infomation. Those of you hwo really wanted to help would have asked orignal author to clarify. Not to poke fun at sombody for not knowing how to correctly use this forum. I will not respont to the other dribble I see in this thread.

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pmdeuel

#32786

SMT component mis-aligned | 21 February, 2005

we have a HSP 4796, and have had placement issues with 0402's. If you can rule out global correction, rev'ed boards and a loose nest or a lack of support under the board. Look at placement before reflow. If alignment problems are present before oven then try slowing handleing rate to 0.16s or 0.18s. This has solved our placement issues. Also look at package deffinition and tolorance. Check part alignment useing verification utility to see if part is aligning with cross hair. Hope this helps.

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#32787

SMT component mis-aligned | 21 February, 2005

Start by verifying the component definition, the thickness is critical. HSP 4796 uses nozzle 81 for 0402's. Make sure is using the right nozzle. If you need to, use the autoteach function to physically teach the dimensions of it, thickness included.

Do you have enough board support? Is the PCB thickness correct? This is critical as well.

A quick fix, like someone else mentioned, is to have a tac time of .12 sec-.15 sec on the component database. The default is .10 sec.

Clear your feeder b-offset before you start running and look at the monitor, if you put it on step mode, you will see if the component is centered in relation to the nozzle.

Components that small don't need that much vacuum so I doubt that the component is rotating on the nozzle. Check your vacuum levels just in case.

How about your paste? do you have 100% pad coverage or is it reduced?

Hope this helps.

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#32788

SMT component mis-aligned | 21 February, 2005

Is it before or after reflow?

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#32790

SMT component mis-aligned | 21 February, 2005

I agree w/ JB; the package height definition is crucial. I have had problems w/ this in the past, and found that a resistor height was being used as a universal passive height for the capacitor in question. Properly defining the height fixed the problem immediately.

Also, make sure the equipment is properly calibrated. I don't know about HSPs, but on Fuji's (CP4 and CP6, anyway) the table must be trammed every so often and z-zero properly set.

I must admit it was fun reading through the thrashing...

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siverts

#32809

SMT component mis-aligned | 22 February, 2005

The first thing to do, as always with any trouble shooting, is to try to isolate your problem area, then it is much easier to pinpoint and find a solution for the problem.

Some simple checks you can do, besides the good suggestions you got from some of the others: 1. Make sure that the length of your board support pins on Your HSP is correct. On that machine the board support pins depends on the board thickness (+/- some tenth's of a mm). It's in the machine manual. Thick pcb - shorter pin's. 2. Check Z-axis adjustment. 3. Check air kiss on the placement station, to much and the components will blow away, to little and the components will follow the nozzle up and then drop down. It's in the manual. 4. Check your nozzle tips for no protruding and that the nozzles are moving freely. 5a. Is it only 0402's? 5b. If so, then you can bypass all other components in the program and concentrate on the ones causing problem. Make sure to turn on those/some again afterwards, for comparement. 6. Is it on the whole pcb area? 7a. Is it the very same positions or random? 7b.If it is the same positions; Is your placement coordinates ok? 8. Is the pcb clamped properly on the x-y table? 9. Is the data for the component, in the component library ok? 10. You can do an overall turret speed slow down, to very slow (0.99sec/placement), so that you actually can see what happens. Are the components placed good with turret in slow motion? 11. You can also put sticky tape on the pcb and place the components on that. 12. If you answer the above questions, then it will be easier for us to help you, or maybe the solution will come clear to you by itself...

13. If You can not find the solution here at this forum, I would suggest that You to contact a service engineer from your local vendor, sometimes even a simple telephone call can makes a difference. But remember, the basic questions will always need an answer, no matter what. Good Luck.

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Steve Combs

#32833

SMT component mis-aligned | 23 February, 2005

We also have 4796's and 4791's and have had the same issues with 0402 parts.. All the suggestions listed in the last post will help quite a bit. We found our biggest problem was the board supports due to the operators using the wrong type of pins , not located correctly, etc. We are using Production Solutions Red-E-Sets and the support problems went away. The are great for double sided boards so you don't have to try to find a open spots for the tooling pins. Hope this helps. http://www.production-solutions.com/Inline.htm

Not affiliated with Production-Solutions, just passing along what worked for us.

Steve

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Brent Robinson

#32844

SMT component mis-aligned | 23 February, 2005

Another this to check is the feeder itself and packaging. The feeders have a little shutter covering the part when the feeder advances. We have noticed a static charge build up in that, or the parts, causing the part to pull out of the pocket when the shutter pulls back. Causes upside down and sideways components. We are still investigation this issue here.

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SMTUser

#32873

SMT component mis-aligned | 24 February, 2005

One other thing to check is your PEC camera. Universal uses a jig to calibrate this camera but you could check it using this method. 1.Run about ten 0402 parts on tape with the PEC camera off and check placement. If the placement is off change the x\y offset in the device data until your placements are acceptable. 2. Turn the PEC camera back on and run the parts on tape once again and check your placement. If the placements are off change the PEC camera offsets until placements are acceptable.

Hope this helps...

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