Author Topic: Screen Tensions....???  (Read 39707 times)

Offline alan802

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Re: Screen Tensions....???
« Reply #105 on: January 14, 2013, 03:28:05 PM »
I personally think that video was more like it.  The closeup pic has some loss of edge definition due to either poor EOM or the double stroke can do that if your pressure is a bit high.  I didn't see near as much bend in the blade and less ink leftover behind the stroke.  What did you think of the prints compared to last week?
I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it -T.J.
Those who expect to reap the blessings of freedom, must, like men, undergo the fatigues of supporting it -T.P.


Offline ebscreen

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Re: Screen Tensions....???
« Reply #106 on: January 14, 2013, 03:30:32 PM »
Sharp squeegees are pretty important.

Buy a roll of squeegee material and get to it.

Can't be neglecting one of the most important tools in the process.

Offline inkman996

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Re: Screen Tensions....???
« Reply #107 on: January 14, 2013, 03:38:55 PM »
First point: GET RID OF THAT RUBBER!

It must be ancient and probably poor quality, I never seen squeegee get so bad its tearing, not here any ways because we replace it as needed.

The video i agree with Alan it looks pretty spot on for what you have, all that could get better with better screens and sharp squeegees.

Two things I noticed tho in your video, one is that your flood stroke is bottoming out at the end and knocking into what ever is at the end of the linear rail,, that could spell disaster for registration and probably hard on the mechanicals. To me it appears you shoot your art work to high up in the screen. Which then causes you to have to go as far as you have to do with the flood. You have nothing else in that screen so lower your art work down another inch at least.

Also the OC looks wicked high, I know its because of lower tension but that right there is some serious OC especially considering the lowest OC is what we all strive for. Higher tension screens will help big time in that area.
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Offline Screened Gear

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Re: Screen Tensions....???
« Reply #108 on: January 14, 2013, 03:40:57 PM »
It looks like during the first pass the screen is still sticking to the shirt. Take your ink over to your manual press and print a few shirts. See if the ink is too thick modify it over on your manual then bring it back to your auto. This helped me in the beginning. It eliminated one of the variables. Clean the bottom of your screen also. that can be doing the soft edges.

Offline alan802

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Re: Screen Tensions....???
« Reply #109 on: January 14, 2013, 03:46:26 PM »
Now that I look at it, Mike is right about the artwork being too high on the screen.  OC does look high.  Get a ruler under there and measure the distance from the bottom of the screen to the pallet if you could.  That will get us something concrete on your OC.  Print speed doesn't look too much slower to me but it has been a while since I saw the other video.
I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it -T.J.
Those who expect to reap the blessings of freedom, must, like men, undergo the fatigues of supporting it -T.P.

Offline Rocfrog

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Re: Screen Tensions....???
« Reply #110 on: January 14, 2013, 03:47:39 PM »
I personally think that video was more like it.  The closeup pic has some loss of edge definition due to either poor EOM or the double stroke can do that if your pressure is a bit high.  I didn't see near as much bend in the blade and less ink leftover behind the stroke.  What did you think of the prints compared to last week?

Sorry for the non HD quality video....LOL!! Best I can do with my iPhone.  8)  But I think reading the things you guys are saying and just tinkering with it, I think this print is more what I was looking for. I can definitely see a difference in the print and I can clearly see the "clearing" of the screen. And based on this info and these tests I think I can say that everyone here (at this shop) has a this stuff backwards! Any time we run into issues it's always "increase pressure" or "do two swipes" or "just flash it and hit it again" never really looking at the true problems or mechanics of how this should work.

I still have not messed with the off contact at all. A few weeks ago I thought I'd check it based on what the manual stated and it said to put a dime on a penny and the is how far off it should be. Well that didn't really work......I would get it that close on the outer edge of the pallet but it would be touching in the back, so I broke out the level to check the boards and they were all level so I don't really know what is wrong there. So I just put the off contact bar back where it was and left it alone.


Sharp squeegees are pretty important.

Buy a roll of squeegee material and get to it.

Can't be neglecting one of the most important tools in the process.

I have heard this before and I am beginning to see that more and more. But once again that is a cost and is not up to me to make that call. I can only suggest that we do it and see what they say......

Nick

Offline Inkworks

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Re: Screen Tensions....???
« Reply #111 on: January 14, 2013, 03:55:21 PM »
Your screen need to be parallel(or darned close to it) to the platen. Equal off contact in the front and back and from side to side.

I think your screen mesh is so loose that you're having to compensate with big off contact, high squeegee pressure, and you're still not getting a good rolling snap off following closely behind the squeegee stroke.

I don't see any easy fixes until the screen mesh is tighter. It doesn't have to be super tight, but you're going to need ~15 newtons or above to get away from having to overcompensate with off contact and squeegee pressure.

If the screen isn't coming off the substrate a second squeegee stroke won't do much if anything for you.

You could increase off contact slightly to achieve a good rolling snap-off, but if you go above about 1/8" you start causing other problems.

Somebody send him a tight screen of the same mesh to play with!

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Offline Rocfrog

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Re: Screen Tensions....???
« Reply #112 on: January 14, 2013, 04:02:37 PM »
First point: GET RID OF THAT RUBBER!

It must be ancient and probably poor quality, I never seen squeegee get so bad its tearing, not here any ways because we replace it as needed.

I would love too! I'll look into some pricing this week and talk to the owners and go from there.


Two things I noticed tho in your video, one is that your flood stroke is bottoming out at the end and knocking into what ever is at the end of the linear rail,, that could spell disaster for registration and probably hard on the mechanicals. To me it appears you shoot your art work to high up in the screen. Which then causes you to have to go as far as you have to do with the flood. You have nothing else in that screen so lower your art work down another inch at least.


Not sure what you mean that the "flood stroke is bottoming out"...??? The "carriage" (as I'll call it) doesn't actually hit anything, the sensor stops it just before the end. This is how all our screens have always been "burned"...using as we call it "four fingers down" method. I know once again it is not the proper way but it is the only way I've been shown. We have (rolled up in the corner) one of those fancy printed out "guides" on "film" from M&R but I have no clue how to use it!

Nick

Offline Rocfrog

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Re: Screen Tensions....???
« Reply #113 on: January 14, 2013, 04:05:48 PM »
Ok here's some crappy pics of the OC...

Leading, outer...edge of the pallet...


back, inside edge of the pallet...


Nick

Offline inkman996

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Re: Screen Tensions....???
« Reply #114 on: January 14, 2013, 04:17:01 PM »
A quarter inch OC wow not good dude. Best to get that press paralleled but thats a whole other topic.

Yes when the flood gets to the end its a bit abrupt "rough" if your saying thats the way it acts when it hits the stop then cool but really seems to rough to me.

You will probably hear a lot of different measurements from us but I bet we are all with in one inch of each other and that is 7 to 8 inches from top of the screen. I try use 7 6.5 if desperate but rarely. Art at that spot is in the screens sweet spot all over and as I said keeps the print carriage from bottoming out on the flood stroke.
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Offline ebscreen

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Re: Screen Tensions....???
« Reply #115 on: January 14, 2013, 04:21:45 PM »
Tell the powers that be that using old dull squeegees is like a carpenter using a butter knife to cut wood.
Seriously.


This is Chinese made polyurethane but it's light years ahead of what you currently have and probably
the lowest price around:

MSJ Squeegee

Of course there is better products, no US made that I know of though. But if price is a major issue (it should not be
for something like squeegee) than $75 shipped free is a bargaining point.

Offline Rocfrog

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Re: Screen Tensions....???
« Reply #116 on: January 14, 2013, 04:29:22 PM »
Well the "orange-ish" squeegee that is on press right now (in the video) is the "new one", I think we replaced it last February so it's probably a year old.....is that too old...??? and what does the term "Sharp squeegee" actually mean? Just that is has a "crisp" edge as in not "rounded"?

Nick

Offline Rocfrog

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Re: Screen Tensions....???
« Reply #117 on: January 14, 2013, 04:31:43 PM »
A quarter inch OC wow not good dude.

But like I said, if you look it's like an 1/8" on the outer side and 1/4" on the inside.....But all the pallets are level both front to back and side to side....

Nick

Offline ebscreen

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Re: Screen Tensions....???
« Reply #118 on: January 14, 2013, 04:32:54 PM »
Crisp is a good word for it, yes.

Run your finger along the edge, it should feel sharp. Not cut you sharp, but not dull either.

Offline inkman996

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Re: Screen Tensions....???
« Reply #119 on: January 14, 2013, 04:45:23 PM »
Well the "orange-ish" squeegee that is on press right now (in the video) is the "new one", I think we replaced it last February so it's probably a year old.....is that too old...??? and what does the term "Sharp squeegee" actually mean? Just that is has a "crisp" edge as in not "rounded"?

Nick

I buy our material by the roll and cut down. I always keep a few small pieces lying around to use as a gauge. Just by feeling the edge of the fresh material compared to the used material I can tell when it's dull. We splurge here and get nothing but triple duro but I don't think it's neccesary, any decent new rubber is going to help even just a little.
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