Quickmaster 46-2 - poor quility on gloss prints

[VZD180i]

Can someone please help me to identify the problem:

When printing on gloss 113gsm 2 colours. (red and black) the image qaulity is very low as atttached photos will show.

Things i have tried to do:
1 - Played around with pressure - no goood
2 - Gave more and less ink - still the same
3 - Cleaned blanket each 250 sheets - worked well for 50 prints then the same

We dont normaly print on gloss, so I am not familiar with its issues.

Thanks

 

[mrheidelberg]

New blanket and packing ?

 

[Inky]

Try a little tack reducer, my QM does this sometimes.

 

[VZD180i]

Thank you for the quick responses

Another stupid question, can exsessive pressure cuase this? I changed the blanket and packing a week ago, but I have put a tad bit more packing (0,05mm) under the blanket, this in cause moved the packing due to the pressure toward the back of the blanket and cylinder causing a thumping noise and tearing of some of the blanket "vulcanized" rubber coating. I removed some packing and the bunch of packing that moved toward the back. The thumping noise is gone but then this issue started, is it then that I maybe removed to much packing?

I am going to print gloss again today but on thicker stock 200gsm (previous run was on 113gsm). I will see if this helps.

Inky - I will contact my ink supplier and ask for Tack reducer. Correct me if I am wrong, if the pressroom is warm enough that the ink will not be so thick and also affect the tack or not?? The 2 colours was Fresh black and Warm red - I suspose both are spot colours. Not sure if the black is Process Colour, will go and check.

 

[ExpertVisual]

I don't print on glossy a lot but when I do, if the blanket isn't hand-cleaned really well I think I've experienced that before too.

To me it looks like it's a blanket issue seeing as it's doing it for both colors. Do you have any brand new blankets & new packing you can put on? Make sure that blanket is tight so you don't get that thumping noise too. Clean all cylinders also make sure those babies are super clean & maybe even put some car wax on the bottom cylinder & a layer of blue etch after that. Helps keep the ink/paper edge build up off slightly better.

Sometimes I lose image quality too when my chemicals need changed for my platemaker...though, I don't think this is the case. But make sure those chemicals are fresh so you are getting crisp plates.

When running your press, what Dampening Setting do you run on for each head (1-6)? I definitely notice I've had to give it a lil extra ink when running glossy though rather than uncoated stock. Try giving it more ink than normal. Maybe even if you have to dab a little bit extra onto the rollers. See what that does.

But ya, #1 I'd give it either a really good wash down like 3-4 times over or just try a new blanket & packing.
& #2, I'd try giving it some extra ink. More...maybe even much more for glossy. Keep trying & good luck

 

[VZD180i]

ExpertVisual - Thanks i will definitly try to wash the blanket extra clean. If i may ask what exacltly is blue etch, we are in South Africa and the stuff here is normaly called something else? And what do you use to clean the Impression cylinder with, my cylinder has a buildup and normal roller wash does'nt clean it enough?

The blanket was replaced about a week prior to this problem. New packing as well. I think I put to much packing cause the thumping noise was loud and you could feel it on the press, so I took out some packing. Thumping was gone but could not see if this made a difference in print. Is it possible to get a problematic blanket from the suppliers?? And "packing" just to clear it up, can you use any type of stock and build it up to the required thickness or is there a specific type of packing like those you get from Heidelberg self?

Thanks for the advice, wil implement on following gloss run.

 

[Swifty2]

looks like chemistry to me..how long ago was the platemaker freshened up?sometimes youcan just add to straight activator and it brings it back to life.(done that at fri 5pm to get the job out LOL)
Also I hope you did not ruin the press by over packing!!!!!!!!!!

 

[maverick1971]

Hi VZD180i,

I am in South Africa also. Where are you located?

Drop me an e-mail - info@acaciaprinters.co.za

Maybe we can help you. Are you new to the press? How long have you been running your machine?

Regards

Shawn