TSB
screen printing => General Screen Printing => Topic started by: jerryperrish on May 03, 2017, 08:20:58 PM
-
I recently started trying out Wilflex white inks (Quick White/Amazing Bright) and am having a problem that is baffling me. I just can't seem to find a consistent way to cure the ink. I'm using a BBC Little buddy 240v dryer with heat controls. This ink is very obvious when it's too hot. It gets puffy and has that orange peel look. But when I speed the belt a smidge or adjust the temp just a hair, the shirts will fail a stretch test. (After a few hours. It passes an immediate stretch) I just don't understand why I can find a balance or consistency here. My temp gun has the ink hitting 320 about half way in the oven and existing about 10 seconds later around 380. I just don't see 380 not being hot enough to cure fully with a PFP on a 110 mesh.
ANY thoughts would be appreciated!!
Side note: I questioned if the shirts were getting too hot during production while being flashed, but that wouldn't cause cracking right?
-
My initial thought is the ink may be printed on too heavy and your temp reading is showing only for the top coat where the entire layer down to the shirt is not fully cured.
I do use a temp gun like you, but many here prefer the "donut" that gives a temp reading from the inside of the shirt under the print for testing.
Outside of that, I got nothing.
-
You might have to raise / lower the heating panel in addition to adjusting the heat control to find a happy medium. 380F is too hot, which can cause some of the issues you're describing. There should be an adjustment for the heating panel height inside the dryer, but I'm not too familiar with that model.
When you flash, you should try to gel the ink, 135-165F.
I would be a second vote for the donut probe and meter. The IR guns are not accurate. As soon as you can, think about finding a larger electric or gas dryers. The very short ones just do not give you much room for adjustment and are barely adequate (my opinion).
-
Thanks for your suggestions, so far guys.
Unfortunately, this dryer model doesn't have the option to raise or lower the element. I agree that 380 is too hot and I also would imagine you're correct that the whole ink layer isn't reaching temp. But, if the top IS 380, you really think the bottom would be THAT must lower in a P/F/P on a 110 print?
I also thought humidity could be an issue, but when printing on 100% cotton, I generally run the shirts under the flash dryer first to expel any moisture before printing. Truthfully, I've never had a complaint and when I do wash tests, the ink isn't going anywhere (so far). I'm just really in my head about this because of the stretch test. How much should plastisol realistically stretch? It's possible that I'm freaking out over nothing.
Do you know an affordable donut probe/meter that I can get that would be still be accurate?
-
Also....
When you flash, you should try to gel the ink, 135-165F.
My flash is about 5 inches off the palette, yet will read about 300 within a couple seconds, yet the ink will still be wet to the touch. This would lead me to believe that the temp gun is reading way too hot, BUT the orange peel look when the belt is too slow does indicate that the ink IS indeed too hot in that instance and the gun isn't all that off.
This whole thing is maddening. Haha
-
When I think of ink curing, i think of my first steak I cooked when I was a kid.... Charcoal black on the outside and raw on the inside.
Try to lower your belt speed(allow time for the heat to penetrate to the lower layer) and lower your temperature (so top layer does not burn).
-
My flash is about 5 inches off the palette, that seems kind of high to me I run my flash on our manual about 3" from the pallet, then again what type of flash infrared or quartz.
-
Hi All
Epic Quick White and ABW will cure at 300 - flash base white until "touch" dry print 2nd white and fully cure. Always wait until shirt and ink is cool before doing the stretch test. A probe is a great investment, try your local distributor. Your final cure temp as already suggested is "too hot"
For updates on Wilflex products always check the pib's at www.wilflex.com (http://www.wilflex.com) as cure temperature testing and validation is ongoing, the aim is to have lower cure temps
-
I think that small electric dryers should be illegal because of all the heartache and pain that they cause.
I started with a Little Buddy and now have an Econo Red 1. They both need disclaimers that read "Do not use if you are suffering from bouts of depression or will likely suffer from depression. Using this dryer may cause lack of sleep and loss of appetite. Some have reported thoughts of suicide while most start drinking heavily."
I don't think there is a consistent cure while using one. Seems like everything changes the cure temp from a breeze in the shop to humidity and the demand on the electrical grid at that moment.
380 on an IR gun probably isn't that hot. The guns I used always ran a lot hotter than the donut probe.
The biggest problem I found to getting consistent cure results was setting the temp and belt speed to the rate at which you are printing the shirts. Especially with the Vastex, I have noticed that if the dryer sits with no shirts going thru for a couple of minutes the first ones that do are going to be way to hot. By the time you get the third or fourth the temp seems to level out. Not sure why. The chamber isn't that big or dampened to hold the heat. I think it's because the deck below the belt gets hot so the first shirts thru get baked from both sides.
I suggest that when you check the temp, feed 3 or 4 shirts thru one right after another and check the difference between the first shirt and the last.
-
I think that small electric dryers should be illegal because of all the heartache and pain that they cause.
this. i started to write something similar earlier and then deleted it as it wasn't really helpful.
but just be aware that getting a good ink cure in a small electric dryer is very very hard to do consistently and nigh-impossible to do WELL, no matter what you do.
more tunnel. gas.
if those aren't viable options, go slower for a longer dwell, if you maxed out the slowness, run the shirts through 2 or 3 times as needed.
-
Just to be clear, I ran, and made a good living, for years with a four foot Ranar Scamp that did not even have sides, merely a panel mounted above the belt. It did however, allow for adjustment up and down. And yes, I ran white, and ran it through 110's, p-f-p. Heck, many folks start out with only a flash dryer!
That said, there were times, when to feel better, I'd run stuff through a second time Though plastisol cure is not really cumulative, by positioning the garment slightly differently the second time, it assured more complete coverage with a relatively small panel.
As for temp guns, they are only good in a relative sense, since even when right on top of the target, they are only measuring the surface. On my ten footer, I get a reading spike of 370-400 just for an instant just before exit. I have kinda' learned how that relates to an actual 295-315 cure. Of course, different shirt fabric, color, and weight all play a part as well.
Just a few months back, we had a poll on temperature measuring techniques. http://www.theshirtboard.com/index.php/topic,19498.msg184333.html#msg184333 (http://www.theshirtboard.com/index.php/topic,19498.msg184333.html#msg184333)
Multiple washings, ideally 24 hours later, still represent the best test.
Another Little Buddy thread. http://www.theshirtboard.com/index.php/topic,11332.msg107847.html#msg107847 (http://www.theshirtboard.com/index.php/topic,11332.msg107847.html#msg107847)
-
Multiple washings, ideally 24 hours later, still represent the best test.
Another Little Buddy thread. [url]http://www.theshirtboard.com/index.php/topic,11332.msg107847.html#msg107847[/url] ([url]http://www.theshirtboard.com/index.php/topic,11332.msg107847.html#msg107847[/url])
Just curious on why 24 hours? Theoretically, if it takes that long for the ink to stabilize then is is possible that the ink is cracking a bit because I'm stretching it too soon? (several hours later) Should I wait a full 24, then attempt to stretch? Am I grasping at straws here?
For the record, I haven't had any shirts wash out after multiple washes. I'm just weirded out that there IS some cracking when stretched. I ran shirts today wit the power around 60% and the belt at a snails pace. and once again some shirts show signs of being too hot, while others not all the way cured. I just don't understand how it can shift THAT much.
-
I can't give you any technical explanation, but am mostly relying on comments from Colin, a member here with background in the ink business at QCM.
here's an old thread that touched upon it. http://www.theshirtboard.com/index.php/topic,5749.msg63852.html#msg63852 (http://www.theshirtboard.com/index.php/topic,5749.msg63852.html#msg63852)
Also, perhaps you just stretched harder than even cured ink could handle.
-
Also, perhaps you just stretched harder than even cured ink could handle.
I was actually hoping this was correct, but I took another print of mine and tried to get it to crack like Hulk Hogan ripping his T shirt. Nothing...It stayed in tact. It's just completely inconsistent.
-
Well, let's think about inconsistency then. Why might your temperature fluctuate? The most obvious reason is airflow.
Can something be changing to sometimes allow breezes to affect the dryer?
A window or door that is not always open?
-
Unfortunately not. I'm pretty anal about making sure there is no real air flow. Honestly, the only thing that has really changed is the Wilflex ink. I'm going to grab a quart of something else and see if the results vary. That would be fairly heart breaking because I LOVE the opacity/mat down/feel of the quick white.
-
Unfortunately not. I'm pretty anal about making sure there is no real air flow. Honestly, the only thing that has really changed is the Wilflex ink. I'm going to grab a quart of something else and see if the results vary. That would be fairly heart breaking because I LOVE the opacity/mat down/feel of the quick white.
Are you getting similar results with the Amazing Bright White ?
Before switching ink ask your supplier for a sample of Epic Quick with a different batch # I would be surprised if there is an ink consistency issue on a shirt to shirt basis - but give the the above a go first.
Regards
Phil
Sent from my iPad using Tapatalk
-
Unfortunately not. I'm pretty anal about making sure there is no real air flow. Honestly, the only thing that has really changed is the Wilflex ink. I'm going to grab a quart of something else and see if the results vary. That would be fairly heart breaking because I LOVE the opacity/mat down/feel of the quick white.
Do you have a heat press?
If so - get one of the shirts on which the ink is cracking - press half of the image @ 190 Celsius for ten seconds - allow to cool and do the stretch test - if one half still cracks and the other doesn't, you definitely have a temperature fluctuation issue.
Good luck
Phil
Sent from my iPad using Tapatalk
-
Can't wait to see if this problem gets solved because getting consistent cure results has always been my main problem also.
Ink film thickness could be one issue. Are you printing each shirt with the same number of strokes? I would think that if you double hit some shirts and single hit others then flash and again double hit some and single hit others it would create different cure results.
Does the Little Buddy heater controls actually cycle the heater panel on and off to maintain a temperature or is it continuous on with lower wattage?
-
Stand by... I talked to reps from BBC and Polyone today. I'lm going to do extensive tests tomorrow equipped with 4 different kinds of white, temp strips, temp guns, and a case of beer.
-
What mesh on the beer?
-
Ok. So I made a ton of prints and notes today. Tomorrow is going to be a laundry day.
In all of your opinions...Do you think the print should look EXACTLY the same after washing, or would you say SOME change is standard (such as a slight decrease in opacity due to the fibers of the shirt)
Also, let's talk about signs of undercure....Besides the obvious washing out, or cracking ink, is there anything else to look out for? What about overcure? I've heard of ink getting chalky and flaking off, anything besides that to keep an eye out for?
note* All prints were on the same black 100% cotton shirts.
-
When we test inks. We cut the image in half. One half for wash. The other for reference.
Sent from my SM-G930F using Tapatalk
-
Sooooooo....... Extensive testing really may have me even more confused then when I started. It's WILD how a temp gun can be reading a surface jumping upwards of 400 while temp strips on top of the garment are just getting 290. I experimented with so many variations. I really thought that turning the temp way down and running the belt so slowly that the shirt was in the 2 foot tunnel for over a minute would be the key, but at the end of the day I still don't have an actual sense of how hot this ink layer is actually getting.
Would a donut probe even work properly in a tunnel this small?
I feel like my takeaway from all this is to A.) Count my blessings that I've never had a complaint. B.) Continue business as usual, but really start putting away some money to get a bigger dryer that will help me sleep at night a little better.
On that note, Does anyone have some recommendations? I don't have a TON of room, so I'm still looking to be on the smaller side within reason. I know that BBC does make a version of this dryer with a 4 foot tunnel and Vastex has some newer dyers that are on the small side, but modular so you can add heat elements as you grow. Any thoughts?
-
Sooooooo....... Extensive testing really may have me even more confused then when I started. It's WILD how a temp gun can be reading a surface jumping upwards of 400 while temp strips on top of the garment are just getting 290.
You may have missed this post back in the poll and threads about different ways of measuring cure temperature. The temp strips require some special attention.
Voted donut but the strips, if they are accurate, are smart as you can "map" your cure on a specific garment if need be.
You may remember that back on the old board, I often recommended putting strips on the inside, to really know that the bottom of the ink deposit has reached temp.
btw, I cut them down the middle lengthways, and double my stash.
Putting it on the iniside is brilliant! If not and you use an electric dryer and a temp strip you will effectively
Measure the emissivity value of the temp strip!
-
Sooooooo....... Extensive testing really may have me even more confused then when I started. It's WILD how a temp gun can be reading a surface jumping upwards of 400 while temp strips on top of the garment are just getting 290. I experimented with so many variations. I really thought that turning the temp way down and running the belt so slowly that the shirt was in the 2 foot tunnel for over a minute would be the key, but at the end of the day I still don't have an actual sense of how hot this ink layer is actually getting.
Would a donut probe even work properly in a tunnel this small?
I feel like my takeaway from all this is to A.) Count my blessings that I've never had a complaint. B.) Continue business as usual, but really start putting away some money to get a bigger dryer that will help me sleep at night a little better.
On that note, Does anyone have some recommendations? I don't have a TON of room, so I'm still looking to be on the smaller side within reason. I know that BBC does make a version of this dryer with a 4 foot tunnel and Vastex has some newer dyers that are on the small side, but modular so you can add heat elements as you grow. Any thoughts?
You want some real confusion? I purchased a donut probe a couple of years ago and there was a 40 degree difference from what the temp gun read. I've tried the temp strips also. If I cured according to the probe then every shirt would come out as ashes. I have an 8 foot chamber mini sprint and I'm just using the temp gun and shooting for the surface to come out of the chamber at 360 to ensure the bottom layer hits the above 320 mark. I've never had a shirt come back uncured and I have several that I wear at the house that have been through several washings from as long as 5 years ago that still look as good as when they were printed except for the shirt it self.
-
Not necessarily an answer to your problem, but we used a Little Buddy for several years, and cured thousands & thousands of shirts with that thing. After one large order being returned due to undercure/cracking early on, we made it our standard procedure to run everything through twice. Since the heat controller cycles on & off to maintain temp, and the panel is so short, I believe it's possible to get one shirt on the "low" end of the cycle and another on the high, which could cause inconsistencies from shirt to shirt. (I think this is what lrsbranding was getting at earlier.) Also, we flipped the shirts around on the second trip, to account for any unevenness from one side of the panel to the other, which we sometimes noted. To make sure that the ink deposit hit 320 on the bottom, we aimed for somewhere around 350-360 temp gun reading. (380 was out "danger zone," where we knew the scorching was likely.)
To test cure, we did occasional stretch tests, but not with every order. I don't recall any other orders returned due to cure other than that first one.
Hope there's some shred of help in there for you.
-
I actually cut the strips in half and had one on the outside and one on the inside.
A buddy of mine let me borrow his heat press, and sure enough, that solved the problem. Clearly not an optimal situation, but it will give me some peace of mind until I move onto bigger and better things.
-
....Since the heat controller cycles on & off to maintain temp, and the panel is so short, I believe it's possible to get one shirt on the "low" end of the cycle and another on the high, which could cause inconsistencies from shirt to shirt. (I think this is what lrsbranding was getting at earlier.)...
We had a different cheap dryer, the cycle caused alot of problems for us as well. The heating elements can be off for over 10secs.
A buddy of mine let me borrow his heat press, and sure enough, that solved the problem. Clearly not an optimal situation, but it will give me some peace of mind until I move onto bigger and better things.
If you are going to use a heat press, you can reduce the power of the dryer to save electricity(Just be careful not too low that the ink is still wet). Then let the heat press do the curing.
Just remember: METALLIC INKS, double your time in the heat press.
-
Open your gates up on your dryer and check the temp of your elements, we have a small dryer and yes a donut probe will work, just did this test with Danny and PJ from Screen Process/Easiway. The donut probe was dead on where the temp gun was all over the place, but compare to price the temp gun gives me somewhat of a good reading, but a donut probe would really be something good to have in your shop if your having curing issues if you can bare the cost, it's like having a tension meter something I thought I would never need but finally broke down and bought one.
-
Thanks for all the input guys. I'm definitely processing it all.
Hey stupid question....Has anyone tried sending the shirts through the dryer (a second time) inside out? Theoretically, you'd be hitting the bottom of the film easier
-
I tried that once and ended up with bad ghosting... not a fun day at my shop.
-
Thanks for all the input guys. I'm definitely processing it all.
Hey stupid question....Has anyone tried sending the shirts through the dryer (a second time) inside out? Theoretically, you'd be hitting the bottom of the film easier
Actually, that could depend on exactly what fabric you were going through.
Otherwise, that's a trick that's been used for waterbased inks when forced air is not available.