screen printing > Newbie
Ghosting/shadow on print
Gilligan:
I have been having some issues.
I have it working now but I'd rather the process be easier.
When I pull the squeegee, I'm not getting a good "clearing" of the screen. I notice where the ink deposit isn't very strong there is still ink in the mesh. Making me have to lay down some HEAVY ink.
I'm also having the issue of topic... after lifting the screen I end up with a shadow. I think what is happening there is that as I flood the screen I'm putting some ink down. I'm having issues flooding the screen obviously. It just doesn't feel right.
So, what I started doing which has "resolved" the problem is push strokes and not flooding the screen unless I pick it up off the shirt first.
So I'm guessing my problem is off contact. I am achieving my off contact by taping nickels to the screen at the four corners of the platen.
Is this not good enough or am I barking up the wrong tree?
jsheridan:
--- Quote from: Gilligan on August 25, 2011, 02:10:17 AM ---
So I'm guessing my problem is off contact. I am achieving my off contact by taping nickels to the screen at the four corners of the platen.
--- End quote ---
If you have wood or aluminum screens with low tension mesh you may need to raise off-contact as much as 1/4" to get the screen to clear.
95% of all your print related problems can be resolved with screen tension, at a minumum mid 20's, using the glisten method of coating (front page) and increasing your exposure times.
DouglasGrigar:
--- Quote from: Gilligan on August 25, 2011, 02:10:17 AM ---When I pull the squeegee, I'm not getting a good "clearing" of the screen. I notice where the ink deposit isn't very strong there is still ink in the mesh. Making me have to lay down some HEAVY ink.
--- End quote ---
Squeegee angle and pressure... ink in the mesh is often a lack of pressure, seeing that odd quote “kiss the shirt with ink” is difficult for manual printers because it makes us think of butterflies and fuzzy bunnies - look at the pressure, speed and angles used on an automatic and the invisible unicorn of “kissing the shirt” starts to make you wonder how it ever came about it just does not fit. Now digging in and laying lots of excessive pressure is also not the key and sadly for new people the best printing pressure, speed and angle change when the ink viscosity changes.
--- Quote ---after lifting the screen I end up with a shadow. I think what is happening there is that as I flood the screen I'm putting some ink down. I'm having issues flooding the screen obviously. It just doesn't feel right.
--- End quote ---
Could be you identified the problem also the phenomenon of “mesh rolling” caused by less than correctly tensioned / low tension mesh can cause.
--- Quote ---So, what I started doing which has "resolved" the problem is push strokes and not flooding the screen unless I pick it up off the shirt first.
--- End quote ---
Diamondback L
The above is a youtube video of an automatic from MR showing the print and flood cycle up close - note that the flood happens after the substrate (on the platen) drops out of the way - flooding happens off the substrate, this is normal. Touch the substrate with the flood and a transfer of ink can happen.
--- Quote ---So I'm guessing my problem is off contact. I am achieving my off contact by taping nickels to the screen at the four corners of the platen.
--- End quote ---
Coins? is your press not capable of holding off-contact?
--- Quote ---Is this not good enough or am I barking up the wrong tree?
--- End quote ---
More ideas are sure to come - have you considered making an video and posting a link in this thread to show the problems and how you are printing?
Gilligan:
--- Quote from: jsheridan on August 25, 2011, 02:45:22 AM ---
If you have wood or aluminum screens with low tension mesh you may need to raise off-contact as much as 1/4" to get the screen to clear.
95% of all your print related problems can be resolved with screen tension, at a minumum mid 20's, using the glisten method of coating (front page) and increasing your exposure times.
--- End quote ---
I thought of that also and that may very well be the case... BUT... this is a FRESH Pocono Screen (from flynbrian on ebay)... granted it is wooden frame and has been sitting in a box for at least 6 months (probably closer to a year.)
I am getting a drum tension meter in soon (another ebay) and that should give me a clue. I know it's not "proper" but at $30 bucks vs $200+ hands down a good alternative... plus it was get an "idea" now or get the real deal in 4 years or something when I can justify that sort of purchase. :)
DanK:
Sounds like you're flooding the screen with it resting on the shirt? You need to flood the screen off the shirt.
Navigation
[0] Message Index
[#] Next page
Go to full version