Search found 1233 matches

by Frank Burgos
Tue Jun 18, 2024 8:56 am
Forum: Pressroom
Topic: Additive for solvent-base ink flexographic
Replies: 1
Views: 45

Re: Additive for solvent-base ink flexographic

Many people use glycol. However, many also keep it locked in cabinets, because it can easily be misused and mess up you ink and product.

There are charts available for solvent types and drying rates. You may be able to find them.
by Frank Burgos
Tue Jun 11, 2024 11:04 am
Forum: Pressroom
Topic: Solvent-base ink flexographic for coated PP woven bag
Replies: 3
Views: 78

Re: Solvent-base ink flexographic for coated PP woven bag

Hi Thinh, Thanks for explaining. Unfortunately, I am not an ink chemist. I let the ink people do that, and then I follow their suggestions and guidance for how to best use their ink for my specific situation. They are the starting point. Once I understand the ink, I can begin to experiment and troub...
by Frank Burgos
Tue Jun 11, 2024 9:40 am
Forum: Pressroom
Topic: dots around negative space while printing
Replies: 5
Views: 75

Re: dots around negative space while printing

I've seen that many times, and I can't recall the cause or solution. All I can offer is that you create a small matrix of variables to track as you make adjustments and keep a sample for each set of conditions.
by Frank Burgos
Sat Jun 08, 2024 10:25 am
Forum: Pressroom
Topic: Solvent-base ink flexographic for coated PP woven bag
Replies: 3
Views: 78

Re: Solvent-base ink flexographic for coated PP woven bag

Hi Thinh, 1. There is no 'reference formula' for ink. There are many variables and possibilities when it comes to ink composition and performance. I suggest you provide more details on your situation. 2. Dabbing your hand is not a good test. Inks have properties that you measure and maintain, and th...
by Frank Burgos
Wed Jun 05, 2024 11:06 am
Forum: Pressroom
Topic: Repeat length and number of teeth
Replies: 10
Views: 402

Re: Repeat length and number of teeth

You're welcome.
by Frank Burgos
Wed Jun 05, 2024 10:03 am
Forum: Pressroom
Topic: Repeat length and number of teeth
Replies: 10
Views: 402

Re: Repeat length and number of teeth

Makes sense, for a 10mm press. You're printing wide web.

The tape is probably 0.020, but it doesn't matter.

28.3464 / 3.1416 = 9.0229" print diameter
9.0229 - ((0.107 - 0.005) * 2) = 8.8189, the diameter excluding the soft part of the plate

8.8189 / 9.0229 = 0.9774 or 97.74% distortion.
by Frank Burgos
Wed Jun 05, 2024 9:46 am
Forum: Pressroom
Topic: Repeat length and number of teeth
Replies: 10
Views: 402

Re: Repeat length and number of teeth

They use 10 pitch gears so how would the distortion be calculated for a repeat of 28.346 with 72 teeth? Hi ESF_PRINTERS. I also wrote an article on the difference between CP and DP: https://flexoexchange.com/cp-versus-dp.html Your gears are 10mm CP, or "circular pitch". To calculate disto...
by Frank Burgos
Wed Jun 05, 2024 9:38 am
Forum: Pressroom
Topic: Repeat length and number of teeth
Replies: 10
Views: 402

Re: Repeat length and number of teeth

I wanted to use HOLOMEX’s numbers to illustrate, but I’ll do this, instead. Way back, in the age of troglodytes, I was training some guys on a narrow web press in the swamps of Georgia, USA. The subject came up, so I went up to a white board to teach them about distortion. I would make this video di...
by Frank Burgos
Tue May 28, 2024 3:07 pm
Forum: Pressroom
Topic: Drupa
Replies: 1
Views: 130

Re: Drupa

Not I, but have a great time!
by Frank Burgos
Fri May 03, 2024 10:25 am
Forum: Pressroom
Topic: Repeat length and number of teeth
Replies: 10
Views: 402

Re: Repeat length and number of teeth

HI Dan. What is the gear pitch? I believe that's what you are calling 'teeth in millimeter'
by Frank Burgos
Fri Apr 26, 2024 4:45 pm
Forum: Pressroom
Topic: Deep Die Cuts
Replies: 5
Views: 303

Re: Deep Die Cuts

Keeping the anvil clean was my first thought but you got that.

Something that occurs to me is variation of depth of cut. If depth is varying, I'd investigate die pressure and die-station rigidity. Consistent cut depth requires a robust setup and no movement. Check bushing, bearings, etc.
by Frank Burgos
Wed Apr 24, 2024 10:46 am
Forum: Pressroom
Topic: Repeat length and number of teeth
Replies: 10
Views: 402

Re: Repeat length and number of teeth

If the 'teeth in millimeters' is the 'gear pitch', the repeat length is simply number of teeth * teeth in millimeters.

To calculate the 'deformation', which we call 'distortion', let me know what gear pitch and number of teeth and I'll calculate the distortion here.
by Frank Burgos
Wed Apr 24, 2024 9:52 am
Forum: Pressroom
Topic: Odd setup
Replies: 11
Views: 676

Re: Odd setup

I forgot, too! Until I remembered :)
by Frank Burgos
Tue Apr 23, 2024 9:30 am
Forum: Pressroom
Topic: Odd setup
Replies: 11
Views: 676

Re: Odd setup

One thing I do with those presses, when I think I've gotten the adjustments all messed up, is I take a mounted cylinder and, with the press stopped, the anilox not rotating, and the station in print position, I place the mounted cylinder where it goes but do not put in the shaft, yet. Then, I make t...
by Frank Burgos
Fri Apr 19, 2024 10:11 am
Forum: Pressroom
Topic: Odd setup
Replies: 11
Views: 676

Re: Odd setup

It sounds right, to me. I have scratched my head to develop a technique that I could also teach, but I haven't. At the end of the day, I tell folks that "this is how this works and it's up to you to develop a technique that ensures minimum anilox-to-plate and plate-to-substrate. That's the goal...