Turnbar Help

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NewbieDeluxe
Posts: 4
Joined: Tue Feb 07, 2023 8:26 pm

Turnbar Help

Post by NewbieDeluxe »

Hey all!
We have a 17" MA 2200 with a turnbar that we use for eyemarks. There was a while where we were struggling to get enough air to it, but at this point we're able to get a solid 15 PSI to it, which seems to be adequate for nearly all of our needs. Right now, we're experiencing an issue where is coming out of the turn bar with vertical scratches in the facesheet. We've cleaned all we can, made sure that each of the whole under the substrate are clear and tried a different face sheet but it's all coming out scratched!? We've also let our tanks load up and ran at 20 PSI, but that didn't seem to fix it
I had a few questions for the pros out there:
How much air are you feeding into your turn bar?
Do you think we just need more air?
Is there anything we could lube this with, without affecting our facesheet?
Taking sandpaper to the edge of the holes is a bad idea, right?

Any help would be awesome
Thanks ya'll! Big fan of the forum!
Frank Burgos
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Re: Turnbar Help

Post by Frank Burgos »

Another potential factor that occurs to me is tension
Frank Burgos
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Re: Turnbar Help

Post by Frank Burgos »

Allow me to elaborate, a little.

With some machines, you can adjust tension with a knob or button, so adjusting tension becomes a normal thing.

With other machines, tension is "fixed", with the ratio of the speed between the exit nip and entrance nip being regulated by a mechanical device, called by a few names that I forget.

Whatever you call it, it is often set and forgotten. If it is set so that the exit nip rotates at too great a rate relative to the entrance nip, one can experience excess tension and may not even know it because they weren't aware the darned thing existed.

Whatever the case may be, if you have excess tension, it could overwhelm the air pressure. That's what I mean.
NewbieDeluxe
Posts: 4
Joined: Tue Feb 07, 2023 8:26 pm

Re: Turnbar Help

Post by NewbieDeluxe »

Awesome! Definitely a good call, that was one of my first thoughts, maybe we need to reduce the tension even further.
What would you set your air to on a 13" width turnbar? Is 15 PSI in the ballpark?
longtimefan
Posts: 428
Joined: Sat Jun 13, 2015 1:10 pm

Re: Turnbar Help

Post by longtimefan »

without seeing how it’s configured, could you have a web wrong?

Check all the air holes from your bars. Make sure they’re not plugged.
MShalna
Posts: 15
Joined: Wed May 31, 2023 8:09 am

Re: Turnbar Help

Post by MShalna »

NewbieDeluxe wrote: Tue Jan 23, 2024 6:48 pm Awesome! Definitely a good call, that was one of my first thoughts, maybe we need to reduce the tension even further.
What would you set your air to on a 13" width turnbar? Is 15 PSI in the ballpark?
What is the width of the web and what is the substrate?
NewbieDeluxe
Posts: 4
Joined: Tue Feb 07, 2023 8:26 pm

Re: Turnbar Help

Post by NewbieDeluxe »

We're running a 12" width of a gloss BOPP.
We have all the holes open on the substrate and all the holes closed that are outside the substrate.
Thanks for all the insight everyone
dkelley
Posts: 282
Joined: Fri Jan 08, 2010 12:26 pm

Re: Turnbar Help

Post by dkelley »

On our 17'' presses we use a bar from DMS called Web on Air. They work great.
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