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screen printing => Equipment => Topic started by: brandon on July 19, 2012, 03:42:22 AM

Title: Auto - Push or Pull
Post by: brandon on July 19, 2012, 03:42:22 AM
Hey Peeps,
Please excuse my ignorance on Workhorse Autos. Falcon M to be exact. I just read they have the option to be push or pull on the print. I know on M&R's through a few other printers on here you can take an hour or so and make it "push" instead of "pull." We are an M&R shop and are happy and am not going to mess with our equipment. I do know from said printers they were happier with the prints and less ink was deposited. So I see savings as I am sure so does everyone else. Not trying to start any auto war on here and who makes better presses. I just think it is cool if the press already comes set up with that feature. Yes our Sportsmen E has both water base and plastisol print fills/floods. But it pulls the ink, not pushes it. Again, we have no problems, works like a charm. I just prefer on most manual print jobs to push, not pull. Again, lots of variables to go over here and not getting into that. I just think on an auto if there is a "flip of the switch" and you could push that might be awesome. Think of zip up pullovers with pockets. Getting late and just read the brochure so fill me in please!
Title: Re: Auto - Push or Pull
Post by: ebscreen on July 19, 2012, 12:47:28 PM
I believe the MHM E-Type's have the option of printing inward or outward. Not necessarily push/pull but it would deal with
the over the pocket print issue.
Title: Re: Auto - Push or Pull
Post by: Inkworks on July 19, 2012, 08:04:46 PM
I'd be really interested to hear from anyone who has done push-printing on an auto. My Falcon E can do it but I've never flicked the switch. I push-print on the manual 99% of the time and have often wondered about it on the auto.

My main concern with it is that at any sort of squeegee angle, a dry screen or even a wrinkle on a shirt could cause the squeegee to catch and it basically has no-where to flex without flexing into the platen and I foresee losing screens.
Title: Re: Auto - Push or Pull
Post by: brandon on July 20, 2012, 12:36:04 AM
I'd be really interested to hear from anyone who has done push-printing on an auto. My Falcon E can do it but I've never flicked the switch. I push-print on the manual 99% of the time and have often wondered about it on the auto.

My main concern with it is that at any sort of squeegee angle, a dry screen or even a wrinkle on a shirt could cause the squeegee to catch and it basically has no-where to flex without flexing into the platen and I foresee losing screens.

Wow, so it really has that feature to try out. Man, give it a shot when you can and let us know please!
Title: Re: Auto - Push or Pull
Post by: Screened Gear on July 20, 2012, 12:49:53 AM
I'd be really interested to hear from anyone who has done push-printing on an auto. My Falcon E can do it but I've never flicked the switch. I push-print on the manual 99% of the time and have often wondered about it on the auto.

My main concern with it is that at any sort of squeegee angle, a dry screen or even a wrinkle on a shirt could cause the squeegee to catch and it basically has no-where to flex without flexing into the platen and I foresee losing screens.

Wow, so it really has that feature to try out. Man, give it a shot when you can and let us know please!

I'm pretty sure the squeegee holder is just adjustable in both directions. So you just keep adjusting the angle until its a push squeegee.
Title: Re: Auto - Push or Pull
Post by: inkman996 on July 20, 2012, 08:17:24 AM
Has anyone ever printed with the flood bar?

I was afraid to mention this before because of nay sayers but one time i was printing a graphic just above a pocket and it needed to start right at the pockets edge. The problem I was having was the squeegee was catching the edge of the pocket on the print stroke and smearing the bottom edge of the print. I decided to try something radical and I switched print directions and used the flood bar as the printer and squeegee as the flood and unbelievably it printed perfect! I didnt think the flood bar would work and i would have to switch the FB with the SQ but I didn't have to.
Title: Re: Auto - Push or Pull
Post by: alan802 on July 20, 2012, 10:09:24 AM
I've set our press up to push stroke and it was very difficult to get the settings just right to get a good print stroke.  It's been a few years since I did it and I can't remember the details, but the results were not good enough for me to ever try it again.  I just think the mechanics don't set up well for a machine to push stroke.  Pushing is one of those things that is very "feel" based in my opinion and is why it excels in the manual print department.
Title: Re: Auto - Push or Pull
Post by: 3Deep on July 20, 2012, 10:29:07 AM
Reinventing the wheel is not always a good ideal, leave well enough alone

Darryl
Title: Re: Auto - Push or Pull
Post by: starchild on July 20, 2012, 04:38:49 PM
Haha! I'm so green, I always thought that pushing was relegated to manual printing for controlling the squeegee and physical benefits.

So after the squeegee achieves optimum angle, pressure and speed, what else on press benefits from a directional preference? Are autos not designed to achieve these optimal setting in it's default direction? And one more question, if pushing/pulling is relegated to the stroke itself and the pump as orchestrated between the substrate, mesh, stencil and squeegee is also optimal what difference does it make what direction the stroke comes from? I don't own an auto..
Title: Re: Auto - Push or Pull
Post by: Screened Gear on July 20, 2012, 05:15:13 PM
Please review...
Title: Re: Auto - Push or Pull
Post by: alan802 on July 20, 2012, 05:18:35 PM
If you really look at the two closely the dynamics are slightly different, if they weren't, why would the push stroke give better results manually.  I haven't put too much thought into why it would or wouldn't work on the auto so I don't know the answers.  I just know the day I did it, it didn't work so I moved on and never thought about it again.  The blade edge is in contact with the mesh at much the same angle but the ink must shear differently because of the angle being behind the ink instead of in front of it.  Who knows, it's Friday and I've worked 12 days in a row and looking at 13 before I get a day off.
Title: Re: Auto - Push or Pull
Post by: ebscreen on July 20, 2012, 05:22:08 PM
I think the push under pressure is backwards. It depends on your angle of course, but I would think the squeegee would bend
up and not down.

And pull under pressure is what you want for waterbase.
Title: Re: Auto - Push or Pull
Post by: Screened Gear on July 20, 2012, 05:23:50 PM
I think the push under pressure is backwards. It depends on your angle of course, but I would think the squeegee would bend
up and not down.

And pull under pressure is what you want for waterbase.

The push under Pressure does bend that way.
Title: Re: Auto - Push or Pull
Post by: starchild on July 20, 2012, 06:40:40 PM
I did not know autos pulled. I assumed manual printers were adopting the behavior of an auto. I read a few articles on push vs pull but never in regard to an auto or I think my assumption came from an article in some trade about imitating an auto.