problems with underbasing

[Shanarchy]

I hate the idea of adding a reducer to my inks. Ideally, I'd rather find an ink that just needs a good stir. What are you using for your white? And are you adding anything to it? Also, what squeegee duro are you using?

 I've tried a handful and find it hard to believe there is going to be something dramatically easier to work with than the Miami (which isn't dramatically different than others).

[screenxpress]

I always use a 156 to 160 for underbase.

Wayne,

You print manually, do you find it a struggle getting the white through a 160?

Something I've wondered recently is the rubber top Vastex pallets. It seems to be a different type of rubber than other pallets use. It seems softer (could be my imagination). Could my printing surface be softer than other presses (hard wood, standard rubber coated aluminum pallets)?

I'm manual and have the typical melamine pallets.  I use QCM Glacier White which is pretty creamy and no, don't really have a problem clearing the ink.  I'm also using a triple durometer (90/70/90) flood and then push stroke.   My off-contact is 1/8 inch and I have retensionables at about 27-30 newtons.

That's an interesting thought on the rubber top pallets on a manual.  Don't know the answer, but I would think since plastisol is supposed to lay for the most part on top of the shirt, I'd be surprised if the rubber topped pallets are an issue.

[Frog]

I hate the idea of adding a reducer to my inks. Ideally, I'd rather find an ink that just needs a good stir. What are you using for your white? And are you adding anything to it? Also, what squeegee duro are you using?

 I've tried a handful and find it hard to believe there is going to be something dramatically easier to work with than the Miami (which isn't dramatically different than others).

First off, before whites were as friendly as they are now, a Union tech addressed the issue of "Won't reducers or bases affect the opacity of my whites?" with this bit of advice," Not if that's what it takes to clear the screen."

As it is, I only find myself adding base or reducer to the occasional "climbers"
My old IC low viscosity, and then eventually Zenon, Wilflex Artist, and my present Streetfighters all clear a 160 just fine.

[Rockers]

What really helped us a lot was changing from a 128N RollerMesh for example to a 150S Murakami Mesh. We get a much better base white with a higher mesh count that costs the fraction of the Roller Mesh. Of course I don`t doubt at all that you can get as well a good base white with the Roller Mesh but overall our print quality has improved using Smartmesh.

[Socalfmf]

or Shane you can start listening to me and start making money vs. worrying about screen tension, mesh count and what it looks like!

hahahahah

enjoy Monday!

[Shanarchy]

or Shane you can start listening to me and start making money vs. worrying about screen tension, mesh count and what it looks like!

hahahahah

enjoy Monday!

You talked me into it Sam. I'm closing the business immediately.

Seriously though. I do this because I truly enjoy it.

[Shanarchy]

What really helped us a lot was changing from a 128N RollerMesh for example to a 150S Murakami Mesh. We get a much better base white with a higher mesh count that costs the fraction of the Roller Mesh. Of course I don`t doubt at all that you can get as well a good base white with the Roller Mesh but overall our print quality has improved using Smartmesh.

I was thinking about switching my screens to Smartmesh. I heard that I would want to bounce up to higher mesh counts because the higher mesh counts will give you more open area due to thinner threads. I have a sample at the shop I need to test out so I can figure which mesh counts I should get. I'm also trying to determine if I want to go blot or panel. I love the panels, but to do a lot of screens at once I think it may get too expensive.

Do you use bolt or sur-loc's?

[Shanarchy]

First off, before whites were as friendly as they are now, a Union tech addressed the issue of "Won't reducers or bases affect the opacity of my whites?" with this bit of advice," Not if that's what it takes to clear the screen."

As it is, I only find myself adding base or reducer to the occasional "climbers"
My old IC low viscosity, and then eventually Zenon, Wilflex Artist, and my present Streetfighters all clear a 160 just fine.
[/quote]

I get what you are saying, and it is completely true. But, if other people are clearing their white through a 160, then I should be able to as well. I think I have a different underlying problem I need to figure out before hitting the reducer.

[Gilligan]

We use S mesh and will never go back. 150 is what we use for UB or spot colors, often going to 180's.  get the chart, it will show you all the data you need right along side of their T mesh.

We have also fallen out of love with Miami smooth (we print manual as well.) We got some samples of arctic white by Excalibur and have a new mistress in the shop.

We also had a UB speckle issue with a blue top coat.  This was on 100% poly with Rutland poly white and it was due to the blowing agent (we assume).

Good luck man.

[alan802]

Ok, I've finally got a chance to give my take on this.  I've been printing sample prints on the manual the last month, testing all kinds of inks, mesh, substrates using a six color job so I've seen the things you're talking about.  I've also seen these things on the auto when I was printing but much less often than on the manual.  The peaks and valleys in the underbase are likely the cause of your spots and they are showing up due to the top color not filling in the valleys or the peaks are poking up through a thin layer of top color.  There are several things you can do but the best long term solution would be to move to thin thread mesh.  We still use lower mesh counts with the thin thread mesh unlike most.  Printing with a 123/55 will put a little more ink down than a 156/64 (not noticeable) but with so much less effort and faster print stroke.  That will make your UB much smoother since it's on top of the shirt and has virtually no peaks or valleys in the ink deposit. 

Let's use the 156/64 sefar and 150/48 murakami as an example.  The 150/48 will deposit a very similar amount of ink as the 156/64, but the percentage open area of the 150 is about 20% more than the 156/64.  You'll need very little pressure to clear a thick white ink from the 150.  The 150/48 also is about 40 microns thinner overall giving you a much flatter ink surface to print on top of.

Completely changing out your mesh counts doesn't really help you short term so you'll have to do something in the meantime to get you through.  I'd suggest moving to a higher mesh count for your underbase so you'll get a slightly smoother surface to print on, but you'll lose opacity by doing so.  Since you're manually printing, double stroking a 156/64 won't be that big of a deal and you'll probably get rid of the white specs showing through your top colors with a smoother UB.  You can lower your top color mesh count to gain some opacity and that will for sure get rid of the UB showing through cause your top color will really fill in any inconsistencies in your UB if it deposits a thicker layer of ink.  If you don't matte down the fibers with the higher mesh count then you'll have issues just like you did before so I can't guarantee you won't be trading in one problem for another.  You might have to adjust your ink like Frog said to clear the ink with less pressure. 

We normally don't use higher mesh counts for UB because of the higher print pressure needed and the ink going into the shirt.  It creates more problems if you can't get the ink to clear a 156/64 with two light strokes.  If you can clear the UB through the 156/64 without driving the ink into the shirt you'll solve some of your issues until you get your hands on some thin thread mesh. 

[Homer]

small suggestion. after we print bases - or even stand alone white for that matter, we use a teflon/smoother screen..it will knock down those peaks/valleys Al is speaking of. we use it on almost every job we run. expose a blank screen, tape a teflon sheet to the bottom, toss some ink in it for a "lube" and print it right after your flash.

we found this material works very well.
http://www.stahls.com/heat-press-cover-sheet

[Mark @ Hurricane Printing]

i use wilflex epic sprint white.....156 mesh....60 or 70 durometer (yellow blade)

I have to pull 2 to 3 times to clean the screen

I'm going to see if there is a 156 S-mesh....i think that will require 1 to 2 pulls to clean the screen...the next screes I buy for underbasing will be 156 S-Meshes.

[Dottonedan]

i use wilflex epic sprint white.....156 mesh....60 or 70 durometer (yellow blade)

I have to pull 2 to 3 times to clean the screen

I'm going to see if there is a 156 S-mesh....i think that will require 1 to 2 pulls to clean the screen...the next screes I buy for underbasing will be 156 S-Meshes.

CHeck mesh tension. Use tight screens and harder squeegee. You get closer off contact with tighter screens.  Try using a harder squeegee like an 80 or 90. Keep angle more vertical.

[Shanarchy]

small suggestion. after we print bases - or even stand alone white for that matter, we use a teflon/smoother screen..it will knock down those peaks/valleys Al is speaking of. we use it on almost every job we run. expose a blank screen, tape a teflon sheet to the bottom, toss some ink in it for a "lube" and print it right after your flash.

we found this material works very well.
http://www.stahls.com/heat-press-cover-sheet

I'm manually printing right now, but auto shopping. I was thinking of investing in the action roller screen thing to use as a smoothing station after the flash. This may really help to confirm me doing this. Seems like a great step to throw in that really won't change production time.

[mimosatexas]

I had problems like this for a while until did all the following together for my whites:
2/2 coating round side, drying squeegee side up
using a 70/90/70 squeegee
High angled, slow flood (just fill the stencil, no bulging out of it, which will cause blur
Quick, lower angled pull (or more recently push) stroke
triangle poly excel white (this stuff is expensive, but far and away the best white I've printed manually.  I even use it on 100% cotton because it just blows everything else out of the water)

I no longer have to do a clearing stroke, and a p/f/p with a 110 or 160 static with normal mesh is literally 100% opaque with no fibration and perfectly smooth finish.  The 160 requires a bit more pressure though.  A lot of shops would probably let the first stroke out the door, but I won't.  I do all the same as above with 160 or even 230 for strictly underbasing and just one shot it, but I prefer to simply p/f/p instead of doing a highlight white screen and print the colors on top of the thick deposit for most jobs.