Set-up Times

[Binkspot]

It almost sounds like the press is out a little. If "zero" isn't zero from head to head on the micros you will always be out a little if you are zeroing each head each time. I am assuming you have the pins like Alex not std screen locks securing the frames in each head. For argument sake if head one "zero" is your starting point and head two "zero" is actually to the left 2mm, head three "zero" is 1mm to the right so on and so on it will cause the problems you are having. Assuming everything before the screens get to press is correct.

Next job you set up do not zero all the heads out before putting the screens in. Leave them in the location for the last job. Run a test print and see if you are closer on reg.

To find a cause I would print a film with five large 1 pt cross hairs on it. One cross hair in each corner then the fifth randomly placed. using the same film burn a screen for each head, zero each head and run a test print using a different color in each screen flash between each. Print right on fresh pallet cover. You could even use a small manual squeegee to hit the reg marks to save time. Then you can tell whats going on and make adjustments or corrections. I know its labor intensive but it will solve the mystery. If you want to take it a step further using one screen, zero everything out and do another test print in each head with the one screen moving it from head to head. With a pin system it should be pretty close to dead nuts on in each head.

[TCT]

By chance have you noted if the same heads are off each time? Or maybe change what head you have your first screen in?
Something has to be off at one point that is messing things up. We need to eliminate the variables. I have the same PRU, and on a 6 color I may have to adjust 2 screens by 1/8-1/4 of a micro turn. I usually chalk that up to poor film positioning/tapeing.

How about your top cross hair box, do you EVER move it? I tightened ours down TIGHT and put tape on the rail to mark its position if it ever got moved.

A idea would be to maybe remove the PRU from the equation to try to pin point the problem. Tape a 14x20 or so film with a series if reg marks to the glass on your exposure unit. Then place a screen on the glass, and tape a few cardboard "stops" around the outside of the screen to the glass. This way you can burn 3,4,5, or however many screens you want to try and they should all pretty much be in the same place. Now take them to press and see how close you are.

Does that all make sense? This will establish if the issue is with the PRU or the zeroing of the heads.

Honestly if I was in your situation I  would be on TechSupports ass to have it fixed. If it hasn't been right since day one, it is on them. And in turn they can put it on S.Roque or however they want to deal with it. But you should not have problems like this, something is off.

[TCT]

Since it takes me forever to compose a post, Blink snuck in another good point. Zero may not be zero. It is actually surprising how simple it is to "re define" zero on these presses. So is you find your zero positions are different it can be easily fixed.

Do you know or have the contact info for the guys at Forward printing in Oakland or Phelps in Iowa? There are a few other S.Roques using the PRU here in the states, I can get you their info. Contact them and see how they are doing with registration. I can contact them also if you want.

[Binkspot]

Two more things real quick. After thinking about it a little more if there is a good reference point on the screen holders you could simply make some kind of pointer to attach to a pallet. Zero all the heads then zero the pointer to head one. Bring that pallet to each holder and see if it hits that same point on each holder left to righ and front to back.

The most important thing is to do one thing at a time. If you make five changes at once and then it works you will not know which one solved the problem.

[Ryan]

Ignoring the the initial setup because that was a whole different issue. I'll explain what happened which is why something is not correct and I don't know what it is.
Everything was checked before we went to zero, level pallets, off-contact, heads on plane etc. I have oversize boards so we put one of those on the press. I printed out a film with 6/7 reggie marks that spread out as far as I could. 2 techs verified that I was in the laser crosshairs so that I could not be blamed for mis-registration. First head, printed to board (only using the 4 corner reggies). Flashed and then moved head-to-head and zeroing them out. Now this is what irks me...Immediately burn 4 color job while techs are present, verify that I am lining up films correctly on each screen (so now tripple checked), go to press, print underbase, flash, load other screens and none of them line up on any of the other 11 heads. I check all 3 screens on all 11 heads, nothing. so get to the last head, I dial in 1 of the screens, pull in out and put in a second screen...that one lines up correctly too, third screen goes in and is slightly off....fine its out a little, minimal, I am ok with that.   
So I rezero out the machine using the 2 screens that now line up to underbase. Everything is "better" than it was, not perfect but "better". That whole process threw me for a loop...how can I just zero out the heads and then go to setup a job immediately after and not have 1 screen be in. This is my confusion as to what the hell is going on. There is something that doesn't add up and I don't know what it is.

As far as dealing with the powers that be, we are already working on a solution to this...hopefully, but I have been in contact with everyone on my end to get it fixed. I do have to have my press zeroed again regardless because of my new PRU, so just figuring out a time when to.

Well have a happy Saturday everyone 

[GaryG]

Simple and probably not it but~
Positively have your shirt spray tack welded down?
Shirt can shrink, pull, etc. especially on outer edges.

Above was mentioned to print directly on pallet (no tack)
eliminating any movement of substrate.

Yes one variable at a time:

The most important thing is to do one thing at a time.

Sounds like you have a good head for deduction, you'll get it!

[pwalsh]

on thing that has saved us a ton of time is to preink the screens.  we have a rolling rack right by the press and we put the screens with ink in there ready for the next job.  we invested in the shur-loc squeegie cleaner and we have two full sets of floodbars and squeegies so we always have clean ones.  We use a dts and tri-loc.  we might have to adjust 1 color but usually we are dead on.

the key to the game is to keep set up/take down to a minimum....

sam

I don't believe you Sam, and I think that you're making all of these facts up!  (OK just kidding, I felt like busting some balls on a Saturday)  Look me up and I'll buy you a brewski at the Atlantic City ISS.  Maybe you'll agree to call it all square

[nthezone]

I have the PRU system also, what I have found to cause registration to be out is the pins them self. If you look at each screens when they are on the press, look at how the pins seat to the brackets that are on screens. I have found there to be random gaps between the pins and brackets.  We use a dip tank and the brackets that go on the screens like to build up with gunk. So before we register our films on the PRU we make sure the the brackets are cleaned of gunk. I will caution you that just because the screens seated up nicely on the PRU doesn't mean that they will do the same on press so always check on press also.

[TCT]

What's up Josh!!? Glad to see you stopped in here! Good people on this forum, except for this Ryan guy....

[screenprintguy]

Adding DTS to our shop last year has shaved 75 percent of our prepress and set ups, but now reading some additional hints here that we will apply, I'd love to tighten up even more. Great info on yhis thread!

[bimmridder]

75%? Surely you jest!

[mimosatexas]

maybe they were painting their stencil onto the screen by hand before