I wanted to post this for all since it's a good educational opportunity. Seaming chucks slip due to not "driving" the lid during the seaming process and is evident in the finished seam (2nd operation). As a can rotates around the seamer, any hesitation in the spinning of the can while the seaming roll is engaged can cause chuck slippage. With non marker seaming chucks, you likely will never know it's occurring unless it's really bad, then you'll have a defect know as a "dead head" or "skidder." If the can slips too much, the seam is not finished off; the seaming rolls are only engaged for a nanosecond so it's critical the can doesn't hesitate in the seaming cycle.
The problem has been more pronounced with the introduction of lightweighted lids: CDL, SuperEnd, and OLOF. This is because the lids drive more around the countersink area and not the lip of the seaming chuck. The more popular coated (usually gold in color) seaming chucks then get shiny, slippery, and if the machine isn't perfectly set up the slipping will occur.
I've attached a few photos to illustrate. The seaming chuck in the picture has a clear "band" around the lip where there is some aluminum pickup. This is evidence of where the chuck is driving the lid and is much preferred and by design.
Hope this helps.
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David Garab
SME Cans, Lids, & Seamers
Treasurer, Master Brewers Association of the Americas
District GA
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Original Message:
Sent: 03-16-2023 21:32
From: Paul Jacques
Subject: Can Seamer "Ghost Dimpling"
Hey David,
I appreciate the response. We're running a 202 CDL+ lid. I'm not positive if the chucks are TiNi coated. The only info I have is that they're "Angelloy". We run 12oz, 16oz, and 19.2oz cans. I don't have exact measurements on our pin height off the top of my head but they're set to the specs provided to us by Ball by stainless steel gauges. The problem is also consistent across all size cans. We checked spring pressure on all 4 heads earlier today and they vary between 115-120psi. I'd be happy to set up a call with you early next week to discuss if you're available. Thanks!
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Paul Jacques
Packaging Manager
Boston Beer Co - Dogfish Head Brewery
Milton DE
(631) 245-0561
Original Message:
Sent: 03-16-2023 02:41
From: David Garab
Subject: Can Seamer "Ghost Dimpling"
Correction to my earlier response: Are your seaming chucks TiNi coated?
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David Garab
SME Cans, Lids, & Seamers
Treasurer, Master Brewers Association of the Americas
District GA
Original Message:
Sent: 03-15-2023 13:02
From: David Garab
Subject: Can Seamer "Ghost Dimpling"
Hi Paul,
The short answer is your seaming chucks are slipping in the lid during the 2nd operation.
We can go deeper into it on a call whenever you have some time, but there is a way to correct it.
What lid are you running?
Are they TiNi coated?
What's can seamer pin height?
Lower lifter spring psi?
We can take this offline.
David Garab
404-234-4188
Original Message:
Sent: 3/14/2023 9:53:00 PM
From: Paul Jacques
Subject: Can Seamer "Ghost Dimpling"
Hello all,
We have an Angelus 4V seamer at our brewery. All 4 of our seaming chucks are dimpled to stamp a signature on the finished lid and indicate which head it was seamed by for troubleshooting and traceability purposes. Recently we noticed that the chucks on all 4 stations have been double or triple dimpling the lids. It's still clear what head they are seamed by but something is obviously wrong and causing this. I've heard it referred to as "ghost dimpling" but there may be a different term for it. All of our seaming rolls were replaced earlier this year, they spin freely, and are greased regularly. The chucks are relatively new as well.
Has anybody seen this before and identified a root cause that they were able to correct and eliminate the issue?
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Paul Jacques
Packaging Manager
Boston Beer Company
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