Has Anyone Here Used a Donut Probe?

[ZooCity]

well my experience with mine which I have had 2 years is this:   I did it your way by the book and had the same issues.  But now I lay it on the shirt and watch the temp from there.  I know this is not by the book but it worked for me.  when I did my initial test i did left side , right side, and middle down the tunnel and used a paper to track temp changes.  I have this same test done for different speeds of the belt and with different garment types.  This way I know what to set my speed for each garment type with out changing the temp for the dryer itself.  Hope this helps a little.

That's how I always figured I'd use one.  We got a setup from a kitchen supply and I'll be mapping out our big texair dryer when it's all hooked up.

Shame to hear it's not the supreme testing method it's touted as though for ink cure.  I guess the wash test is the only thing that's really 100% in the end. 

[alan802]

Just a little update, I have been playing with the temp and belt settings and have slowly gone up with the main temp setting on the dryer.  My donut probe results have gone way up as my dryer temp went up.  I got the probe temp up to 320 and 330 with settings at 390 and 22 belt speed.  This dryer also has temp probes attached to the exit area of the dryer and those weren't reading the temps that I thought they should until today, and they were reading 300-320 consistently and that is when the shirt is a few inches out of the chamber.  I am very happy now knowing this donut probe thing is working.  I'm worried the shirts the first day weren't cured all the way, they passed the stretch test but according to the probe readings the ink wasn't cured.  Maybe my stretch testing isn't accurate, or maybe I was just barely getting a cure the other day and now they are curing perfectly.

[Printficient]

Just a little update, I have been playing with the temp and belt settings and have slowly gone up with the main temp setting on the dryer.  My donut probe results have gone way up as my dryer temp went up.  I got the probe temp up to 320 and 330 with settings at 390 and 22 belt speed.  This dryer also has temp probes attached to the exit area of the dryer and those weren't reading the temps that I thought they should until today, and they were reading 300-320 consistently and that is when the shirt is a few inches out of the chamber.  I am very happy now knowing this donut probe thing is working.  I'm worried the shirts the first day weren't cured all the way, they passed the stretch test but according to the probe readings the ink wasn't cured.  Maybe my stretch testing isn't accurate, or maybe I was just barely getting a cure the other day and now they are curing perfectly.

Stretch test only works with inks that have a stretch additive.  Not a good cure test.  Never has been.

[Screened Gear]

Just a little update, I have been playing with the temp and belt settings and have slowly gone up with the main temp setting on the dryer.  My donut probe results have gone way up as my dryer temp went up.  I got the probe temp up to 320 and 330 with settings at 390 and 22 belt speed.  This dryer also has temp probes attached to the exit area of the dryer and those weren't reading the temps that I thought they should until today, and they were reading 300-320 consistently and that is when the shirt is a few inches out of the chamber.  I am very happy now knowing this donut probe thing is working.  I'm worried the shirts the first day weren't cured all the way, they passed the stretch test but according to the probe readings the ink wasn't cured.  Maybe my stretch testing isn't accurate, or maybe I was just barely getting a cure the other day and now they are curing perfectly.

Alan,

Why have you not called M&R. I am sure their service guys can help you. Its part of the dryer that you bought they will know how it works. What changes did you do that its working today and was not working before? Stuff like that scares the crap out of me. My controler on my Exposure unit was going out and it would work some days and then be really hard to use some other days. I called Workhorse and got the new controler and now it works perfect. (I was dealing with it for 2 years)

[ZooCity]

Sprint sounds like a badass dryer, well though out.  I like the temp sensors at exit, do they display or issue a warning if dropping above or below a certain reading?

[alan802]

Just a little update, I have been playing with the temp and belt settings and have slowly gone up with the main temp setting on the dryer.  My donut probe results have gone way up as my dryer temp went up.  I got the probe temp up to 320 and 330 with settings at 390 and 22 belt speed.  This dryer also has temp probes attached to the exit area of the dryer and those weren't reading the temps that I thought they should until today, and they were reading 300-320 consistently and that is when the shirt is a few inches out of the chamber.  I am very happy now knowing this donut probe thing is working.  I'm worried the shirts the first day weren't cured all the way, they passed the stretch test but according to the probe readings the ink wasn't cured.  Maybe my stretch testing isn't accurate, or maybe I was just barely getting a cure the other day and now they are curing perfectly.

Alan,

Why have you not called M&R. I am sure their service guys can help you. Its part of the dryer that you bought they will know how it works. What changes did you do that its working today and was not working before? Stuff like that scares the crap out of me. My controler on my Exposure unit was going out and it would work some days and then be really hard to use some other days. I called Workhorse and got the new controler and now it works perfect. (I was dealing with it for 2 years)

I have, all the way to the top actually.  They contacted me after seeing this thread.  I started at the very low end of the recommended temp settings, actually lower and the probe readings weren't really coinciding with the results that I thought I was seeing, so I posted here.  The only thing I did differently today was just added temp, belt speed is relatively the same, minor changes there.  I was thrown off by my previous experience and dryer along with the only way I really tested cure before, the old stretch test and wash testing.  The garments passed with the very low probe readings which makes me wonder a few things.  I think these inks will cure at much lower temps than they say, or there is something else going on like they really aren't cured despite my stretch and wash tests.

Sprint sounds like a badass dryer, well though out.  I like the temp sensors at exit, do they display or issue a warning if dropping above or below a certain reading?

You can set the rear temp probes to alarm you if the temp goes above or beyond whatever temp you want, it's really sweet.  If you use this dryer up to it's potential, there is no way you'd ever undercure a single garment, ever.  And you'd also not spend a dime more per month on gas and electricity than you had to if you used it right.

[ZooCity]

Alan, I'm also interested to see how your gas bill changes with the sprint.  Glad you got the probe figured out. 

I think it goes without saying that the inks probably fuse at a lower temp than listed, everything needs its wiggle room. 

[inkman996]

Stretch test only tells you one thing and that is under cured. Never use the stretch test to assume something is cured it is only a warning not a guarantee.

[ZooCity]

I don't know where stretch testing really fits into anything.  If you know your ink, deposit and substrate well enough then sure, you can glean some information by "palpating the area" but if you're that intimate with you printing that you can stretch a print a little in your hand to determine cure you could also, say, do a sniff test or something right? 

I think it's truth that the wash test is the only guarantee there is here.  The rest should be control of variables built around a successful wash test. 

I see the donut probe as more of a tool to figure out what's going on in various stages of the cure process inside the chamber.  Questions like "where in the chamber does this ink and that ink and so and so garment reach what temp?". 

Honestly some sort of heat proof humidistat would be nice to send down the dryer with a full load of wb inks as well. 

[ScreenFoo]

LOL @Zoo...
Sniff test...interesting idea, I hear it works pretty well for discharge.   

I'm with you though, customer couldn't care less what fancy stuff you're testing your process with when they're stuck with a box of washouts.

[Gabe]

LOL sniff test
maybe we screen printers should start training our puppy dogs
for this purpose

[alan802]

I know I don't have some special talent that nobody else can do, but I feel confident with the stretch test.  I've done it thousands of times over the years with wash testing thousands that I've stretched and comparing the results.  Like Mike said, you can for sure test for undercure by stretching, but all of the wash tests I've performed on tees that I've stretched over the last few years have given me the exact result I was expecting based on stretching the print.  I've only recently gotten a temp gun and now the donut probe to get more precise results that I'm even more confident with than the good old stretch.  I've never had a shirt washout that passed the stretch, and literally 95% of those that failed my stretch, have failed the wash as well.  I won't suggest anyone who hasn't done as many as I have to use it like I've done though.  Don't do as I do, do the right thing and test your dryer the best way you can afford to. 

I've always been paranoid about prints washing out, so I am constantly testing shirts and the past year I've been trying to find our old dryers maximum efficiency because it used so much electricity.  I want all the garments to reach their cure with the lowest possible gas/electrical usage now with the new dryer that hasn't changed.  I don't want to spend more than we have to and it's all about operating leaner and meaner this year.

[Gabe]

is always good to know when you strecht a print and feel just right in your hands
i`m sure you were worry about ink cracking or washing out with your old dryer
having said that
with your state of the art dryer, is just a matter of days to find the right settings for a good long lasting cure
donut probes and other gadgets,build in the dryer take the guess work out of your mind

[jasonl]

My old shop had 2 sprint internationals and I ran both at 365 with a belt speed of 20, for years!  Never any problems.  I never could get that donut probe that came with them to work correctly, but I didnt put to much time in to it either.  If I am not mistaken, I am pretty sure it tells you to do a stretch test right in the M&R owners manual.

[mk162]

stretch tests are a good STARTING point.