Old Gauntlet Squeegee pressure regulation

[ebscreen]

Oh, and to the OP, excellent work sir! I love seeing new life being brought to old machines.

[DannyGruninger]

the issue is that you not only have a cantilever system where the pressure to the squeegee is coming down from one side, but also that the squeegee can 'float' side to side.  when printing in a high shear, high speed method, you really want pressure on both SIDES of the squeegee, so that the platen and shirt can't cause the squeegee to lift up on either side.  remember, you're just trying to kiss the top of the shirt.

I think that 'self' leveling print head designs like that are nearly as bad as a tuned up old Javelin... you have to print with so much pressure to overcome the rocking potential that now the squeegee is bent over.

Not to derail the thread but I'd love see what you can do on your chopper heads that we cannot do here. Coming from running 5 chopper style presses to the single pin squeegee system I feel I have a great understanding of both systems and what they offer. What experience do you have with the single point squeegee system if I dont mind asking?

High sheer printing in my opinion has way more to do with the proper mesh, ink and blade then what your describing above.

[jvanick]

I have no direct experience with the newer style machines.

however, I have heard reports from people that I trust saying that they're having problems clearing one side or the other side of a screen when printing with super low pressures on some single-point presses.  The only working solution in some of these cases is to just add pressure and let the squeegee deflection act as a shock.

this would seem to indicate that the pressure isn't consistent side to side... which is what a dual-point chopper pneumatic driven system tries to solve.

the chopper presses down with X pounds of pressure on either side of the blade keeping the interface pressure between the blade and the screen (and thus the shirt) consistent.

having a system where the squeegee is free to rock back and forth means you're only pushing down with force in the middle.  The force at either end can be different...  the most apparent form of this would be a see-saw... the middle of the seesaw is like the pin/pivot... the ends are the ends of the squeegee... if one person pushes up, no matter how much pressure the middle has, the other end is going to go down, or vice versa.

[DannyGruninger]

I have no direct experience with the newer style machines.

however, I have heard reports from people that I trust saying that they're having problems clearing one side or the other side of a screen when printing with super low pressures on some single-point presses.  The only working solution in some of these cases is to just add pressure and let the squeegee deflection act as a shock.

this would seem to indicate that the pressure isn't consistent side to side... which is what a dual-point chopper pneumatic driven system tries to solve.

the chopper presses down with X pounds of pressure on either side of the blade keeping the interface pressure between the blade and the screen (and thus the shirt) consistent.

having a system where the squeegee is free to rock back and forth means you're only pushing down with force in the middle.  The force at either end can be different...  the most apparent form of this would be a see-saw... the middle of the seesaw is like the pin/pivot... the ends are the ends of the squeegee... if one person pushes up, no matter how much pressure the middle has, the other end is going to go down, or vice versa.

Ok so no experience with the system, got it! 

I'm quite sure I know who your source is spreading this information out there, and while I can respect the individual I will say I have done tens of thousands more prints then this person on both single point and chopper style systems giving me a great understanding of what can/cant be done. This situation reminds me of when I was professionally racing cars in the aspect that when one manf was not getting the results they were looking for the easiest solution was to blame the next person in line - i.e if the car wasn't fast enough the engine builder would place blame on the chassis builder and vice versa. The same can be said for manufactures in this industry we are in. If an ink manufacture cannot get their ink to perform a certain way then blame is placed on the machine printing it when in reality the recipe might not be met. All machines are different and require different setups/recipes to make work.

We dont print at full speed a lot but when we need to we certainly can. Proper ink, mesh, tension, blade, off contact, etc as you know play a key roll in high sheer low pressure printing. If there are machines out there with single point setups that cannot do this then my thought is they are not calibrated correctly as mentioned we have absolutely no issues printing as fast or faster then any chopper setup out there. We've been there done that, and have done millions of prints with both styles.

[3Deep]

This turned into some good reading and info from all

[Wildcard]

...  I can now control the squeegee pressure in the cylinders via the regulator, and I can dump the air with the switch so I can insert / remove squeegees without having to turn the air off to the whole press.

I have been meaning to add this type of relief/air dump valve to my press. Could you add some more details on the switch you used? I assume it keeps the pressure in the rest of the machine when releasing pressure from the print carriage?

Great work on the DIY upgrade.

[Atownsend]

This has actually turned out to be the one of the best things I could have done for the press, and our shop, as this is our only auto. I went ahead and outfitted 5 of the heads with regulators and switches exception being the flash head. We put up a 5 color on press friday, setup is so much more streamlined. Being able to flip a switch on the head, to remove the constant squeegee pressure to adjust registration is a game changer for our setup time. Doesn't sound like much... but when you have to cut air to the whole press and wait for it to drain out to be able to move the micros on each head, that is a real time killer. Not to mention the extra frustration. This fixes that, and really improves my mental state. Still getting pallet deflection, but much less now that we can dial the pressure back. Registration, setup etc is 100% improved.

For the switch, I used this one https://www.mettleair.com/store/5-ports-3-way-2-position-toggle-valve-1-8-npt-detented.html It ended up being the most expensive part of the retrofit. Im sure I could have used a different one, but i really wanted one that was 1/8" npt so I didn't have to worry about other fittings and such. It is a 3 way switch, with two positions. When the switch is open, the muffler is closed and the chopper cylinders have regulated air pressure, when the switch is closed, the infeed from the press is closed and the remaining air in the cylinders / head is released through the muffler. The rest of the press keeps pressure, no constant bleeding or anything. Its super easy to rig this up, it took the better part of an afternoon to rig up the rest of the heads. Once you do the first, you can use the bracket as as a template for the others. Acrylic is easy to work with and seems to be pretty strong. You do need to extend the 5/32 air line that runs through the guide that holds the proximity flags. And then you'll need a bit of hose to run from the switch back to the manifold on the front of the head.


I would have loved to get smaller regulators, and use less fittings, but harbor freight had these for $9.99 and it was local, meaning I could do it now. I may change them eventually, but for now i'm just stoked that it works! Best thing I could have done. If I get some time, i'll try to take a video of it in action.

The next thing on the list for me now... is to find a better way to clamp in roller frames. This may have been covered somewhere before, but we have the stock screw type clamps with the plastic feet, and have to use the metal shims from newman on all four corners.... which totally sucks. I haven't researched it much, but I'm pretty sure this can be upgraded with parts from the M&R store. Has anyone gone from the posts to a newman compatible bar type system on this press? Ive seen air lock upgrades on similar presses, but I don't think they'd work with rollers. I'm also a little hesitant to go the air lock route, unless I also rig up some kind of manual backup, because I routinely leave jobs on press overnight. But it would be nice to have them nonetheless.