Failed transfers

[ericheartsu]

Looking into why some of my screened transfers are failing. I've had a pretty good system dialed in for years, and now in the past week, every single one is failing, and i'm not sure why. Here is a job i've been working on, maybe you all can help me trouble shoot it:

Russel Gray Plastisol with 15% adhesive powder mixed into the ink.
230 mesh
Printing on PET Film
Running through a quartz dryer at mid speed, at 240.

Heat press
i've tried everything from 325-375 degrees. 40-110psi. 8 to 30 seconds, and i'm still getting loss of adhesion, especially on finer details.

am i geling to low? I've never had an issue in the 3 years i've been using this system!

[Dottonedan]

When everything else has been the same, I look at environment. AS you know, this week has had much colder temps. That plays a role on RH values. Could it affect the inks when heat setting?  I'm sure.  Could re require longer, hotter heat?? I don't know. When combatting humidity changes, over heating may not be as important as duration of the workable applied heat.


Just a guess.

[DannyGruninger]

Have you checked the actual temp of the heating element? We had a similar issue and it was because our heating element was not heating to where it should have.

[ericheartsu]

When everything else has been the same, I look at environment. AS you know, this week has had much colder temps. That plays a role on RH values. Could it affect the inks when heat setting?  I'm sure.  Could re require longer, hotter heat?? I don't know. When combatting humidity changes, over heating may not be as important as duration of the workable applied heat.


Just a guess.

Thought about this, but even with our falling temps, we are still averaging around 50-60 degrees inside.

[ericheartsu]

Have you checked the actual temp of the heating element? We had a similar issue and it was because our heating element was not heating to where it should have.

This is something i do need to check. Our cap hat press just transfered the same transfers with no problem....so i'm wondering if that's the case.

[Frog]

Have you checked the actual temp of the heating element? We had a similar issue and it was because our heating element was not heating to where it should have.

This is something i do need to check. Our cap hat press just transfered the same transfers with no problem....so i'm wondering if that's the case.

Sounds like you may have zeroed in the problem. I had a Stahls press that was fine for vinyl, but gave me fits on ink jet transfers having bad patches.
These heating elements can develop dead spots.
Good use for a non-contact thermometer gun would be to see if readings (though often not accurate due to reflectivity of the teflon coating,) are at least consistent over the whole platen.

[Maff]

Yeah sounds like your heat press.
We've always put the adhesive powder on after the wet print, before the dryer. I thought that helps the transfer bond better to the fabric, like a glue when heat pressed. But I love the idea of mixing it into the ink, sounds way easier and less messy, I'm definitely going to try that next time.

[mimosatexas]

I've never had that method work, just fyi.

[Sbrem]

We had a similar problem with a heat press a couple of years ago, replaced the element and all was fine again. Now, about powdering, we powder after the print, and have thought about mixing it in, though something in the back of my mind kept me from trying that. I do notice that Union has sold heat transfer inks for years, are they simply mixing in the adhesive powder? Obviously, there would be a proper powder to ink weight ratio, but is it that simple? We don't do a ton of transfer work, and never produce them for anyone else.

Steve

[ericheartsu]

Reporting back, i think we were overcuring them. We turned the dryer temp down from 240 to 220, and it's like there is no issue at all.

We also started playing around with HSA transfers, which also gel at this temp. We have to turn our heat, time, and pressure up, but they look and feel great!!

[BrazosDesigns]

Eric -
I ran some neck label transfers for some 100% cotton shirts a few weeks ago and they failed, as well.  Tried some with no powder sprinkled and some with powder - all failed.   Like you, I found out that I had to turn the conveyor down to like 210-220 and speed up the belt, even more so than my usual.  Also, I have found that on single color 1 pass (like for neck labels), I'll just hit it with the quartz flash for about 3 secs and they're good to go...just have to handle them gently.  Used Union Ultrasoft light grey, but will be trying Wilflex Rio to see if I can get that work.  Must be our climate here in the greater Houston area!

I'd be interested in learning how to do HSA transfers....any tips?  I only have Supertrans 15x15" transfer sheets from GSG.

[mimosatexas]

So we use the powder from one stroke inks right now and we are actually sending out transfers through the dryer at 300 just like we are curing a finished shirt (elt and Rio inks). Powder is melted and transfers are super durable on the sheet prior to pressing and we have had zero adhesion issues. I was super worried about it before we tried it, but we tested it a bunch and it works great.

I have tested a few transfer specific inks and while they hold up better than standard inks when you don't use powder, they still always seem to fail prematurely and small details can be rubbed off the shirt or hat. Not having to use the powder would be amazing, but we just trap everything with a final coat of clear just to hokd powder these days unless it's one color stuff with no small details

[Sbrem]

I'm just having to order some some more of the powder, I can't seem to find who I ordered it from last time, since you are doing a ton of transfers, are you happy with the One Stroke powder?

Steve

[aauusa]

we love one stroke powder for transfers

[BP]

Eric, it sounds for me that you are over curing the transfer is dryer like you said. Also keep in mind that most transfer powders a made to put on wet ink. That is how I have done it for year with no problems.


FYI I really like the white stuff.
https://sourceone.nazdar.com/P/4575/White-Stuff-Heat-Transfer-Adhesive---Fine

This low melt powder polyester resin adhesive is used on heat transfer applications. White Stuff is applied to wet plastisol inks prior to the final cure. White Stuff locks the ink onto the substrate with a permanent, durable, and flexible bond.