ENCLOSED CHAMBER LEAKING - VISCOSITY?

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bweimerjr
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Joined: Tue May 23, 2023 9:54 am

ENCLOSED CHAMBER LEAKING - VISCOSITY?

Post by bweimerjr »

HI,
We're running a Gallus 440 label master and we're having trouble with the varnish leaking out of the bottom and the sides of the chamber. I'd take a picture but we're not allowed to have anything like that on the floor. My question, right now we are using white foam pieces on the sides of the chamber and using petroleum jelly to seal it. The sides have the plates that screw on with two bolts. The normal chambers with regular inks (UV) seem to run pretty well with minimal leakage but the varnishes tend to be another story. If anyone has a better setup for running varnishes in these pans that would be a great help. Also, is it possible the problem is such low viscosity that the varnish just leaks through?
Frank Burgos
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Re: ENCLOSED CHAMBER LEAKING - VISCOSITY?

Post by Frank Burgos »

Hi,

The first question I posted on this forum, in 1998, was about leaking chamber seals. At the time, I was operating a 65" W&H.

Ink viscosity likely has an influence. However, I don't adjust ink viscosity to avoid leaking.

Aside from making sure that the chambers are properly aligned, pressures are appropriate, etc., the thing I'd probably do is experiment with materials. There are many options, including foam, neoprene rubber and felt. I've found it helpful to do a little R&D to arrive at the best for most cases and to have a couple of other material options to try when problematic inks or coatings become difficult.

I don't know your configuration, but I ran a few narrow-web presses with UV in the last station. Sometimes, when the UV insisted on overflowing, rather than fight it, I'd divert it back into the sump, careful to ensure the ink remained clean.
Printerman513
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Joined: Sun Jan 05, 2020 10:35 am

Re: ENCLOSED CHAMBER LEAKING - VISCOSITY?

Post by Printerman513 »

stop using petroleum jelly immediately it turns to liquid and melts at around what 120degrees? use the grease to really seal it up long term.
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