who is packing blankets

[NGA]

just wandering if anyone out there is doing the same thing we are. Our pressman for years now have be packing the blankets to the sheet size b/c they are getting ink transfer/ build up on our backcylinders and they complain about cleaning them. we have 2 heidi sm74's. one of which is an 8color. as you can imagine to change out 8 sheets of packing takes awhile and i think is insane that we are doing that. is anyone else having this problem?? we are running branden inks EPTS but are currently trying Van Son V3 series. Prisco 3451 and about 7-8IPA, but are looking into going IPA free with the rise in IPA pricing. what are we doing wrong. we run heidi pro blankets that we pack even to baer. suggestions????
thanks

 

[LoganBlade]

lazy pressman

 

[Lennyr]

Blankets

Blankets

Sounds pretty insane to me (except for coater blankets).

Back cylinders get cleaned at the end of every shift or whenever needed. Fact of life
That's why God created Feeders!

 

[NGA]

i agree its nuts, are you having alot of piling on your back cylinders. i think they originally started packing b/c they were also getting alot of ink build up on the super blues.

 

[Cornishpastythighs]

We pack our blankets to full sheet size and not to sheet size. We have far too many sheet sizes to waste time repacking blankets. We do not experience any of the issues that you are seeing. We run Alcohol free. Time for a culture change.

 

[RKS]

We have a 10 color Komori perfector & a 6 color straight Komori, running VS3 Van Son. We pack the blankets to Komori's specs. Most generally in-between forms we never have hand wash the impression cylinders. We wash them by hand at the end of the shift. We don't change the packing to the sheet size except on the coater unit. We're using Fuji PressMax HDA64 Alcohol Replacement & Anchor Emerald Jr 2637 fountain solution.

 

[Happyprinter]

I agree 100% with what has been posted. Time to have a chat with your pressroom. Sounds like a lot of wasted time and expense. We have always packed to full size and have had no problems.

 

[J.Thomas]

You guys should try using a full packing under your coating blankets as well and cut and strip the blanket down to the sheet size. This results in cleaner lines. Almost all of our coating blanket customers are doing the using coating blankets with a mylar layer in them. They are much more dimensionally stable and they get great results. Just my 2 cents...

 

[RKS]

If you have pre-cut packing already in multiple bars, it's a quick change. That's a lot better than buying a lot of blankets.

 

[J.Thomas]

That is true and there are trade-offs with either system, but I just thought I would mention it because most of our customers are switching over. Going from a small to a large sheet can cause irregularities depending on the quality of the job and when you keep stretching the blanket in different ways it ends up not lasting as long as it could. Just a thought. I am not a printer though! Just an annoying vendor.

 

[NGA]

so none of you are having excessive build up on the back clyinders or transfer cylinder? just cleaning them at teh end of every shift? do you think my excessive buildup is from the plate not staying clean?? i'm not having scuming problems ect...

 

[The Heidelberg Guy]

just wandering if anyone out there is doing the same thing we are. Our pressman for years now have be packing the blankets to the sheet size b/c they are getting ink transfer/ build up on our backcylinders and they complain about cleaning them. we have 2 heidi sm74's. one of which is an 8color. as you can imagine to change out 8 sheets of packing takes awhile and i think is insane that we are doing that. is anyone else having this problem?? we are running branden inks EPTS but are currently trying Van Son V3 series. Prisco 3451 and about 7-8IPA, but are looking into going IPA free with the rise in IPA pricing. what are we doing wrong. we run heidi pro blankets that we pack even to baer. suggestions????
thanks

On long runs (400,000+) I always have my packing cut to the sheet size. On anything under 200,000 impressions, its really a waste of time.

 

[Blanket Bob]

The undercut on a SM74 blanket cylinder is .090" use a .077 (4ply gauge) blanket and a single sheet of .014" paper packing. It's not public information who makes blankets for Heid. if its a high quality product with a strong compressible layer that's all the packing you need and is the way I set up all Heidies running my blankets. Make sure the pressman uses the kiss print method for adjusting back pressure to the substrate durring the MR. If you run alot of thin stocks while the press is over packed and/or back pressures are over squeezed excessive build up on back cylinders will occur. Your blanket supplier should be able to send a technician in to help out.

 

[NGA]

we run heidi "pro" series blankets with a .016 sheet of paper packing under. bear to blanket measures just about even to maybe .001 over and after a few thousand sheets we get to .002 under bear. Use you a blanket bear gauge on a magnet, maybe the magnet is actually squeezing the blanket down .001 or .002 and giving me a false reading and i'm actually over packed. what do you all measure blanket height with. i was thinking about switching to poly packing so the paper doesn't wear out so quick. do you think starting .002 under bear is safe? i'd be worried about getting a good dot then once a get a good few thousand imp. in on the blanket. to me i still think i'm transfering ink on the outer edges of the plate non image area down to the back cylinder.

 

[madjock]

I have only heard of this practice on UV presses, seems like an awful waste of time to me, I run a 105 XL and clean the impression cylinders at the same time as the blankets after each job!

 

[The Heidelberg Guy]

we run heidi "pro" series blankets with a .016 sheet of paper packing under. bear to blanket measures just about even to maybe .001 over and after a few thousand sheets we get to .002 under bear. Use you a blanket bear gauge on a magnet, maybe the magnet is actually squeezing the blanket down .001 or .002 and giving me a false reading and i'm actually over packed. what do you all measure blanket height with. i was thinking about switching to poly packing so the paper doesn't wear out so quick. do you think starting .002 under bear is safe? i'd be worried about getting a good dot then once a get a good few thousand imp. in on the blanket. to me i still think i'm transfering ink on the outer edges of the plate non image area down to the back cylinder.

The Heidelberg "Saphira Pro" is identical to the Day3000 blanket, the Day3000/Saphira Pro is IMHO, the best blanket out there for sheetfed presses.

In my experience, most SM74's are running a .077" blanket and a .016" sheet of packing, and most come to .001" over bear when new, not .003" over as the math suggests. Most of the .016" packing sheets out there that I have measured are actually .0155", and the blankets are usually .0765". With the proper torque (SM74= 34 to 36 fps) you will indeed be at .001" over, plus/minus .0005".

The problem with poly packing is it will crawl up to the gripper edge. The adhesive style is not recommended, difficult to change and sporatic thicknesses.

Always try to stay EVEN with the bearer, never start out at .002" below!

 

[Alex Arriaza]

On long runs (40,000+) I always have my packing cut to the sheet size. On anything under 20,000 impressions, its really a waste of time.

why you cut the packing to the size of the sheet, ive never done that ever, does this procedure gives any advantages?

 

[REYES1377]

The only time packing should be cut to sheet size is if you dry trap print with UV inks. Yes it is a big waste of time and packing.

 

[The Heidelberg Guy]

why you cut the packing to the size of the sheet, ive never done that ever, does this procedure gives any advantages?

With running UV, we dont want blanket to impression drying on the sides and tail of the cylinder, blanket or impression. Our run lengths were in the 1,000,000's , can get very costly washing blankets and impression cylinders.

 

[Dan Roll]

When discussing packing, it is a good idea to remember that when you increase the packing you are speeding up the surface of the plate or blanket and when reducing the packing you are slowing that surface down. Just make sure you do not introduce too much of a speed difference between the plate and blanket surfaces and you will avoid a great deal of mischief....