Squeegee/flood chopper topic

[Stiers]

Great post Alan! I was going to email you one of these days and ask you what pressures you are using. This is perfect. What squeegee & flood speeds are you using?

I've never had much luck printing with higher mesh counts, unless they are a top color. 110, 137, & 160 for underbase. 160 for most colors on light shirts. 200 or 160 for top colors.

The last few months, I've started taking more time to keep my screens nice & tight. Lowered my off-contact. Switched from 70's to 70/90/70. Higher EOM. My prints are really starting to pop.

I was using around 40-45 psi, but with the adjustments I'm now real close to your numbers.

[alan802]

Hey Kevin, glad you found this place.  Nice to have another RPM guy here as well.  Over the last 6 months or so I have really started to experiment with print speed and have been very impressed with how most of the time, printing faster will yeild a more opaque print.  For the first few years I just printed everything fairly slow, white inks were almost always set to 4 (4"/sec for us RPM guys) and I never messed with it.  Now we are frequently printing thick white inks at 10-15, depending on the artwork.  You do have to add some pressure, if you are at 22 then you might bump it up to 24-25 if you are printing at 15 instead of 10 but it's more dependent on if you have thin lines or fine detail the ink has to pass through.  Union ultrasoft brite red through a 156 can pretty much be printed at 30, which is top speed for our press, it's really dependent on the viscosity and shearing ability of the ink and the mesh openings.  For dark ink on light shirts, we used to be consistently in the 6-8 range but now we've bumped everything up to 12-20, and occasionally I'll put it on 25 as long as the ink doesn't start flinging around.

Our flood speeds are always dependent on print length.  On a longer print, maybe 16-18", I'll flood at 14, which puts the flood stroke at the top of the image just before the index is through and the table is ready to come up.  A left chest only needs to be around 6-8.  The rule of thumb I use is to have the flood stroke finish just before the carousel is stopped and ready to lift.  You never want to be waiting around for a flood to finish before the table will lift and start the print stroke, and flooding really fast and way before the index is through can get messy and fling ink around and is no more beneficial really than a slower flood.  Oh yeah, we use a hard flood and it's allowed us to decrease our print pressure by a significant margin, I'd guess around 20% less since using a hard flood.

For anyone who wants to try and get more opacity out of an ink, especially your underbases, try speeding your print stroke up, it really does make a difference.

[Stiers]

Thanks Alan. Glad to finally have something to contribute!! Ha ha.

Up until a few weeks ago, I was printing almost everything with 4-6. And I was double stroking everything. Bill told me a while ago to use a slow flood and fast squeegee. The hard flood helped, but everytime I tried to speed up the squeegee, I could't get it to clear. The faster the stroke, the worse it was.

I lowered my off-contact to almost nothing, and bingo!! Now I am getting much better opacity. I'm guessing since my off-contact was too high, I had to use more pressure to get it to clear. But even though I would hit it twice to get it to clear, it was driving it into the fabric, leaving me a dull print.

The reason I stumbled upon it, was that I was printing black t-shirts. I switched to hoodies, but forgot to raise the off-contact. The hoodies were a lot brighter than the t-shirts I just printed. The only change was the off-contact.

Since lowering the off-contact, I am using much faster squeegee speeds. I'll speed em up even more and see what happens.

[Screened Gear]

For anyone who wants to try and get more opacity out of an ink, especially your underbases, try speeding your print stroke up, it really does make a difference.

Alan,

It’s funny you said print faster this week. I just did that this week. I could not figure out why I could print a really nice print on my manual and then when I go to do it on the Auto it’s a ton of problems. I was printing manually and figured out that I print really fast on my manual. My flood and print stroke was 10 times faster then I have been setting on my auto. I WAS Printing at a 2 or 3 speed (MHM is 1-12 for speed on the flood and squeegee, Even thou I can only adjust it 1-11). This week I set it to 6 flood and 6 squeegee. Works great and I am sure I could set it even faster.

Thanks
Jon

[rmonks]

All this talk of pressure and angle with the chopper style press leaves me out, as my 2001 M&R Gauntlet does not have a pressure gauge on the squeegee pressure. Wonder if I can add this. It looks like a very valuable option when buying a press.

[3Deep]

Didn't read the first post just jumping in right here so If I,m out of line let me know, but anyway I was checking my choppers and what made me check this out is the new winged floodbars I got from Rich at M&R.  The winged floodbars on my press have to be at 0 angle straight up and down...I have the click type adjustments for my choppers and I notice that one side was higher or lower than the other with both at 0.  I checked both choppers and I found out one choppers push rod is about 1/4 longer than the other, have any of you notice this on your presses with your choppers.  They can be adjusted, but there not even in clicks one might be at 3 clicks and the other at 3 1/2 clicks to match so i get the same pressure.  I guess the more you use your press the more things you find as you try to get better at your game.

Darryl

[GraphicDisorder]

We print with pressure, my numbers are higher than Alan's for sure, we basically just adjust until the ink clears the screen. 

We also print about 4-5-6 (1-12 setting) on most jobs.  Keep in mind we are often printing 17 inches on a 23x31 which is near the max you can get out of that on our press with that size screen.  Shorter prints I try to run harder when Shelly will let me. 

[alan802]

Hey Darryl, we have one chopper out of 40 on our press that is just like you say yours is.  I don't know how common it is but I'll bet you money we aren't the only ones that have a slightly different chopper on our press.  Ours is the left chopper on printhead 3 which is rarely used and it is 1/8" higher than the right side chopper.  If I have the right side set at 1.5, I have to set the left to 1.6 which is probably different than other manufacturer's markings.  If that chopper was on a different printhead and we used it everyday, I still don't think it would make one bit of difference but for the sake of being anal about everything, I have thought about putting a shim somewhere to balance that out.

I'd like to add that when printing faster, we have to increase squeegee angle accordingly to get the ink to shear.  Sharp edges to your blades are very important to printing faster too.  I haven't come up with any concrete info to share about which duro works best for faster printing, but the smiling jack blades do allow you to print faster than a regular or triple duro.  If I had to put numbers on the SJ blades, I'm pretty sure the blade itself is an 85 duro, but I think because of the design, it prints more like a 70, but that is purely a guess on my part.  Not that I have any credibility or 1/100th of the experience needed to tell Joe Clarke how to build a squeegee blade, it is of my opinion that the blade duro needs to be less, and because of that the smile of the blade should be flatter with less curvature.  I'd like to experiment with an SJ that was a 75 duro with half of the curve that's on the blade that's made now.  I know all of this was thought through and tested but I've always thought the blade would work even better than it does now with some slight changes.  It's entirely possible that my ideas for the blade could turn it into a worthless tool, highly likely.

[3Deep]

Alan, thats so funny, mine the one I check so far was the #3 print head and its on the left side as well looking in from the front.   I have not checked any of the others, but like you said I really don't think it will make a difference on the print.

[IntegrityShirts]

Hey Darryl, we have one chopper out of 40 on our press that is just like you say yours is.  I don't know how common it is but I'll bet you money we aren't the only ones that have a slightly different chopper on our press.  Ours is the left chopper on printhead 3 which is rarely used and it is 1/8" higher than the right side chopper.  If I have the right side set at 1.5, I have to set the left to 1.6 which is probably different than other manufacturer's markings.  If that chopper was on a different printhead and we used it everyday, I still don't think it would make one bit of difference but for the sake of being anal about everything, I have thought about putting a shim somewhere to balance that out.

I'd like to add that when printing faster, we have to increase squeegee angle accordingly to get the ink to shear.  Sharp edges to your blades are very important to printing faster too.  I haven't come up with any concrete info to share about which duro works best for faster printing, but the smiling jack blades do allow you to print faster than a regular or triple duro.  If I had to put numbers on the SJ blades, I'm pretty sure the blade itself is an 85 duro, but I think because of the design, it prints more like a 70, but that is purely a guess on my part.  Not that I have any credibility or 1/100th of the experience needed to tell Joe Clarke how to build a squeegee blade, it is of my opinion that the blade duro needs to be less, and because of that the smile of the blade should be flatter with less curvature.  I'd like to experiment with an SJ that was a 75 duro with half of the curve that's on the blade that's made now.  I know all of this was thought through and tested but I've always thought the blade would work even better than it does now with some slight changes.  It's entirely possible that my ideas for the blade could turn it into a worthless tool, highly likely.

Wouldn't be an expensive experiment with gradual arched bumper jig and a router with the right bit.  You should get on that! 

[inkman996]

Daryll you bring up a great point.

On our press they did not level the heads when set up, they said it is not necessary as long as the platens and hangers are paralleled. Well not one head on my press is parallel to my platens which means every single chopper cylinder is uneven by quite a few clicks. That is probably why i do not print with air it does not make sense to me to have so much pressure on one side because it needs to compensate for the lower side.

I have always believed and heard that an auto is supposed to be paralleled in three parts, Platens/hangers/print head. According to !@#$ thats not so and they did not parallel my heads only the hangers and platens. I guess it would be to much work for them to have to shim every single head side to side huh?

My head one is the worse it is atleast a 1/2" difference from one side to the next, I don't know much about any thing but I really think that must add some serious unnecessary stress on the clamps and what not.

[tonypep]

Leveling a press is pretty much the same; in principal; for most if not all presses. The actual process varies from both machine to machine and yes; even the technician or operator performing the task. I could walk you through it but this is something far better learned in person. Any independent tech can perform this. All you need to do is assist and learn and you are good to go. I would addess this very soon if not immediately.
Guess all those pictures of shims and levels did not help much.

[inkman996]

Tony the shims on my press are only to raise the over all height of the head not to level it. It is something I can do myself when quieter god knows I spent 15 years keeping our Javelin leveled.

Again i was told it was not necessary to level the head because the choppers will make up for the differences, in a perfect world I wish the numbers on our chopper cylinders were equal side to side.

Look at the pic below and you can see how unlevel my heads are. And yes that is set to have the squeegee parallel to the platen.

[tonypep]

Wow I don't think I've ever seen a press so out of level. I would contact the manufacturer immedi..........oh, sorry.
Anyway good to know you can straighten things out. Sometimes Saturdays are good for projects like these. Having someone help makes it go quicker.

[alan802]

Wouldn't be an expensive experiment with gradual arched bumper jig and a router with the right bit.  You should get on that! 

On second thought, I'll just let it ride as is!