Best way to control dot gain

[Artelf2xs]

As always for fun & entertainment as well as education!

[yorkie]

Dot gain should be controlled by the rip.

[Artelf2xs]

Yorkie,

 Some of do not use rip. We adjust manually to COMPENSATE for dot gain not control it. I am taling about the physical aspect that happen on press.
Dot gain happens.. in all forms of reproduction. some more then others.

[Orion]

On press. I vote for 1-4.

[Sbrem]

I'm thinking 1 though 5 myself. Anyone of them done wrong will have an effect.

Steve

[prozyan]

I'm thinking 1 though 5 myself. Anyone of them done wrong will have an effect.

Steve

I as well.  I was looking for an "all of the above" option.

[Artelf2xs]

Ok, so let's say out of all the options witch one will control dot gain the most? and I forgot to put... Sharpen your squeegee! 

[squeezee]

Dot gain is not a problem.  We can handle it with several of the means mentioned.  Variable dot gain (or any other variable) is a problem because if you are not sure what's going to come out, how can you compensate for it.

[Sbrem]

If I had to pick one, durometer seems to be big in mind, triple durometer, 70/90/70, but really, all of them. Also, the wet white method, the one I learned was making a white printer that was the negative of the other 4 combined. We'd tape the 4 films together, cut a ruby mask around the outside, then create a negative from that stack, of all the white space between the dots of the 4 films. It worked pretty well, especially with the lower tensions of the day...

Steve

[Artelf2xs]

you folks crack me up. Now an admin has added all the above.... My point is that one of the original mentioned is the most critical in controlling dot gain on press.
Not how to adjust films or screens for, or if it is a problem, or workaround solutions.

Which "ONE" element has the "MOST" impact on dot gain?

[yorkie]

Which "ONE" element has the "MOST" impact on dot gain?

The film!

Press gain is predictable and should be controlled upstream.

Anyone tweaking more than 2 of the variables listed has a completely out of control system. How far off must things be that you need to change the Squeegee angle AND Squeegee speed AND squeegee pressure AND Squeegee durometer AND off contact of screen to substrate AND Sharpen your squeegee??? SERIOUSLY, ALL OF THE ABOVE???

How long is the makeready, when everything needs to be tweaked? At the end of every job, are all of the settings restored back to normal or do you just start cranking knobs when the next job is way out of speck, because on the last jobs all of the settings were shifted?

Yes, the press does allow color to be tweaked on press, but the image should at least be in the ballpark when the press is started using the default values, but every knob turned and test print produced is money out the window.

[Sbrem]

you folks crack me up. Now an admin has added all the above.... My point is that one of the original mentioned is the most critical in controlling dot gain on press.
Not how to adjust films or screens for, or if it is a problem, or workaround solutions.

Which "ONE" element has the "MOST" impact on dot gain?

Now that you've clarified it some more, I still think durometer (sharpness included) over the others, but now that everyone wants to change the rules in the middle of the game, it's a little muddy. But with the screens already made, and maybe an older press that doesn't give you the speed and pressure controls (like an old Preceision Oval) the blade is it. Which one do you have in mind, Dave? Or do you want the discussion to go a bit further before you reveal your answer?

Steve

[yorkie]

So do you have a stock of dull squeegees for when the ink is printing too heavy or do you dull them when using sandpaper (?) when you need a dull squeegee?

[Artelf2xs]

Press gain is predictable and should be controlled upstream.

Again, Dot gain does not happen upstream !  It happens as ink gathers around  the edge of the stencil ON PRESS!

Predictable yes.

Simple question. One answer!!!!!! Multiple choice! not Rocket science,,,, sheeesh,.

Which One single answer has the MOST effect of dot gain ON PRESS!!?

[yorkie]

Simple question. One answer!!!!!! Multiple choice! not Rocket science,,,, sheeesh,.

"In the RIP only" was added as one of the multiple choices!!!

OK, so the color on press doesn't match expectations, something has gone wrong.

The first questions is if the issue is with one screen or all of them??

Then the question is if the screen looks correct or not. If the screen is correct, there could be a problem with the squeegee setting or it could be an ink issue or a shirt issue.

I don't look at a dull squeegee as tuning point, as much as it is a maintenance issue.

But if i had to pick one, not including pressure or speed, i'd pick squeegee angle.