Author Topic: Multi belt dryers?  (Read 807 times)

Offline Croft

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Multi belt dryers?
« on: June 20, 2017, 10:13:49 AM »
Im a little confused on these new multi belt dryers , are we saying now that we just need to speed the belt up to cure properly?  but then have the ability recall temp and belt speed on the dryer control panel?,

I cannot run poly shirts at my cotton tee temp by just speeding the belt without having problems. I can't imagine that these dryers are temp regulated side to side.

I have seen the results of just speeding the belt up for red poly , when I have fixed orders from other printers.


Offline tonypep

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Re: Multi belt dryers?
« Reply #1 on: June 20, 2017, 11:37:27 AM »
Its all about retention time mainly (though not entirely). For the most part dryers are modulated by belt speed and temperature. For instance, if the temp setting is 325 and the belt is at rocket speed, the ink film thickness may not hit that cure temp at the designated time if not at all. Donut probe will tell the story and post launder to be sure.

Offline Colin

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Re: Multi belt dryers?
« Reply #2 on: June 20, 2017, 02:58:00 PM »
As I understand it:

Example: We run a gas dryer at 325 degrees.  Our retention time is 1 minute.  This fully cures all plastisol inks and is pretty gentle as far as heat goes.

If we want to run waterbase at the same time... we cant.  If we get a split belt, I slow down the other side until the waterbase is cured.  I still run at 325 degrees.

I may need to slow down the plastisol side to compensate for moisture.  Donut probe for insurance.

Been in the industry since 1996.  5+ years with QCM Inks.  Been a part of shops of all sizes and abilities both as a printer and as an Artist/separator.  I am now the Ink and Chemical Product Manager at Ryonet.

Offline tonypep

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Re: Multi belt dryers?
« Reply #3 on: June 20, 2017, 03:07:06 PM »
That would be correct.

Offline Maxie

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Re: Multi belt dryers?
« Reply #4 on: June 20, 2017, 03:23:20 PM »
Plastisol cures when it reaches the correct temperature.
Water based binders need a certain time at a certain temperature, in most cases a split belt will work well with the belt halfs running at different speeds.
The water base I use needs 5 minutes and the temp will only rise when the water has evaporated..
Maxie Garb.
T Max Designs.
Silk Screen Printers
www.tmax.co.il

Offline ZooCity

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Re: Multi belt dryers?
« Reply #5 on: June 20, 2017, 03:38:07 PM »
Colin summed it up well.

The brown dryer with the quartz bulbs and zoning is the only unit I know of that claims to be able to "zone" curing in the chamber for multiple garments and ink types running at once.  That's not for us for a number of reasons but it does make that claim if it's of interest to you.

I will say that despite having about as much firepower as you can get in a gas dryer here, when you are running full size wb/dc/hsa prints at 600-700pcs/hr, you probably aren't running anything else down that belt.  Belt space : retention time messes up your ability to load two jobs and, ultimately, air exchange rate becomes the bigger factor with all that moisture loading the chamber.  As much as I would LOVE to have one, a split belt wouldn't really resolve that situation.  It would dramatically decrease scheduling headaches for us though with all the performance ink getting ran these days around the wb product.

From experience, plastisol does in fact benefit from a longer, gentler cure.  You see the difference in hand and washability.