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Rad 5 performance: bent lead

Views: 2349

#82945

Rad 5 performance: bent lead | 2 July, 2019

Hi, any idea what can cause 5% intermittent right component lead being bent during CTA transfer to the forks? Yet, everything is line up on these 2.5 mm lead span components.

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#82966

Rad 5 performance: bent lead | 8 July, 2019

I forget which type of CTA that machine has so I probably won't be much help. It's been ages since I worked on them but it doesn't look like you'll find many people that have.

That said, usually if you get things aligned properly and it still bends leads or misses the head it's because something is worn out and won't hold alignment during transfer.

It could also be a carrier clip problem.

When you turn off the air and manually cycle the CTA forward and backward, does it push the parts out of the clip and then return them properly?

If you could post a slow-mo video of a failed transfer that would be a big help, but I realize that's not that easy to do. Even just a picture of the CTA might jog my memory a little.

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#82969

Rad 5 performance: bent lead | 8 July, 2019

Steve, all the worn carrier clips (chipped, spring less or damages, etc.)have been changed for working ones. Alignment has been performed to loser and afterward thighter tolerances than the manual recommend to see if it changes anything (no). I checked the stroke and played with it to be sure the transfer works: it does every time manually without air or in single cycle mode but still fails 5% of the time at full speed.

Attachments:

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#82970

Rad 5 performance: bent lead | 8 July, 2019

My recollection is that there is a carrier clip locator that positions (centers) the clip in front of the CTA. Has the adjustment on that been confirmed as well?

(Edited because some of it's coming back to me!): I think there is a diamond shaped pin that centers the head at the home position. If that's worn it can have problems transferring.

Also, the carrier clips get worn where the clip locator slides past. Not sure if you checked that as well but it's worth mentioning. When that wears they won't get centered properly.

The only other thing I can think of is wear on the head clamping jaws or the part that the jaws clamp the leads on to. I can't remember exactly what any of that is actually called.

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#82971

Rad 5 performance: bent lead | 8 July, 2019

Would you happen to have the Jig used to check that the component itself is in spec with UIC's general specifications? 1.) Component in spec. 2.) Correct 2.5mm pusher on the feeder / dispense head. Also set the conditioner guide where the comp enters the feeder. 3.) Correct alignment of the feeder to the carrier clip. 4.) Correct chain tension and timing (should have been step 2 or 1). 5.) Cutter station alignment and blades. 6.) Bottom component guide height as it starts to enter the inserter just after the cutting station. 7.) CTA alignments (apx 15 different adjustments). 8.) Jaws and springs for the Jaws on the insertion head. One thing that stumped me in the past over a very intermittent CTA issue was needing to change cylinder for the CTA return stroke assist (I can't recall the exact name) but there are two air cylinders in the back - one is obviously used to extend and retract but the 2nd is kind of like a fail safe to ensure the CTA fully retract, it wasn't until changing both of these assemblies AND the Bumper that the machine ran perfect - I believe this was on a RAD 8 not a 5 but the CTA is pretty much the same. If it's coming out of an amo pack and not tape and reel, are the components located by the folded carrier tape coming bent out of the box?

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#82973

Rad 5 performance: bent lead | 9 July, 2019

I would check the clearance between the bottom guide and the carrier clip. Usually I set it .004 below the clop then set the head height .004 above the guide. It's a little tighter than UIC specs but it'll prevent the lead better.

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#82974

Rad 5 performance: bent lead | 9 July, 2019

Watch the air pressure gauge and make sure you have a good steady air pressure. I don't know about the Rad 5 but the Rad 3 was sensitive to fluctuations in air pressure. By any chance do you have a VCD running nearby when you are having the problems?

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#82975

Rad 5 performance: bent lead | 9 July, 2019

Yeah, I struggled at stabilizing it so for now it's ok. It's the only machine on it's air line.

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#82976

Rad 5 performance: bent lead | 9 July, 2019

Good, I came to the same conclusion after recent tests.

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#82977

Rad 5 performance: bent lead | 9 July, 2019

Unfortunately, I don't get the Jig but the component is always the same LED. I measured a sample of those and they are consistent from the tape and after the leads being cut. About 1-2% of the component from the tape are already bent so I'm still focusing on the machine. I'll check for the 2 cylinders. This is unexpected but you never know.

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#82978

Rad 5 performance: bent lead | 9 July, 2019

That's a great point about air consumption, don't reduce the 1/2 inch air line requirement, meet the CFM air requirement and of course dry shop air. Check the Auto oiler for the CTA is running correctly, 5W 30 NON Detergent oil only. Attached is a picture of the jig for reference. It's not a requirement by any means but a great sanity tool when we are dealing with multiple variables and have customers buying components from a variety of sources.

Attachments:

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#82979

Rad 5 performance: bent lead | 9 July, 2019

Have you checked the bearing on the linear slide bearing on the CTA?

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#83005

Rad 5 performance: bent lead | 16 July, 2019

Ok, just got what we needed, thanks again all for your help.

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#83008

Rad 5 performance: bent lead | 16 July, 2019

C'mon, man, spill...what was it? ;)

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