LED's difference between units

[Shanarchy]

We are starting to consider making the switch to LED from our NuArc 3140. It's been a few years so I'm thinking all the manufactured should have made any tweaks needed to get the bugs out by now.

What I'm looking at based upon being able to expose a 23x31 screen

Workhorse (25x36): $2500
Vastex E2000 23x31: $3550
M&R Starlight 23x31: $4200 (price is from 07/14, this may not be current)
Lightspeed 23x31: $4700
Ryonet FX (Saati?) 25x36: $5000

So now the big question is what are the actual differences between the ones I'm looking at. There's a pretty good variation in pricing from manufacturer to manufacturer. Are there different features, or quality of lights, quantity of lights, etc that would make one a higher end model? If not, I'd obviously go with the lowest priced one from Workhorse. But if there are noticeable differences, then I'd rather spend the extra money. Assuming these differences would effect us.

We use Ulano orange (cap film version), so my main concern at this point would be how it performs and exposure times SBQ photopolymer. We will be attempting to get into discharge/waterbase next year.

[farmboygraphics]

Also interested in the differences.

[ZooCity]

I'm not sure on workhorse and vastex but all of those other units use different LEDs.  The Ryonet/Saati is single point/cluster, the Lightspeed array uses intermixed LEDs with different UV wavelengths, the Starlight array uses one type of LED strip at about 400nm. 

Manufacturers of LED units are reserved about sharing histograms of the UV output.  Here's the starlight's though for reference.   Lightspeed has a patent on multi spectral output I believe.  Maybe someone can share the Saati unit's histogram?

For a PP emulsion w.out diazo you'll be very happy with the 400nm range heavy output.  For diazo added and other emulsions it will be significantly slower than a 5k mh but probably still faster than your 3140. 

I think most of the joy people have with the LED units comes from having a less than ideal expo unit to start with.  Anyone moving from 1k mh up to a quality, high powered LED unit is probably going to be stoked.  We went from 5k mh and frankly the 5k mh is superior in most every way except amp draw. 

I also feel that mfg's of these units should incorporate power options for PP emulsion users.   1s expos are not ideal for exposure and faster shooting PP emulsion could benefit from a lower power option, especially in cases where the LED array is already dimmable.

So for PP emulsion you'll be happy with any of the good ones I imagine.  Look at which unit is best fit for your workflow.

Hope that helps. 

[Prince Art]

When I was looking for info last year, the only one I recall mentioning a specific nm range was Ranar (not on your list); they spec theirs @ 400nm.

http://www.ranar.com/screen_printing_equipment/led_screen_exposure_unit.html

[TCT]

Here is what I can tell you, now all my experiences are using a diazo emulsion which led's haven't always been too strong with. I am also stubborn. Breakdown, unacceptable. Hardners and post expose are band aids, and post expose really doesn't do much with a diazo anyway.

Had the Workhorse unit, and returned it. They were very good about taking it back and fully acknowledged it was not made to be used with diazo emulsions.

The Vastex, I didn't have much of an opinion on until Alan went into detail about his experience.

Starlight you hear mixed reviews about. Tons of great reviews, but they also come from very strong M&R shops. I have talked to a handful of users that have had issues and some that say it is just OK, but those are from "not" strong M&R shops. So who knows. My guess is that if the units really weren't great, talk of that would be much more prevalent.

Lightspeed, I have and has become our daily unit. I was skeptical as hell after sending two other companies units back. I had a good set up going exposing 4 screens at a time with a 5k MH unit. I needed a new bulb and those are pricey so I looked again a bit. I am fortunate the manufacturer of the Lightspeed is here in MN and a hell of a nice guy. I bundled up a dozen or so imaged screens in double black garbage bags and brought them over to the distributor to test them. Inside I was really hoping for signs of breakdown during the runs so I wouldn't have to change our process... The dozen screens ran without issue. So I bought one maybe 2 months ago. Not a single issue, we have ran 5,500 units double hit discharge on the screens, taken them down, washed them off, and used them again for another 1,500 prints a few weeks later. Still no issues.
He could/should put a better timer on the machine. The one that is on there works just fine, but the buttons make no sense and could be labeled better.

Ryonet one I don't know anything about aside from it uses a Saati light/cluster.

Hope that helps somewhat!     

[GraphicDisorder]

Happy with our M&R Starlight. We use Diazo. We may be a "M&R Strong" shop, but I am not going to keep something that I am not happy with just for the sake of keeping it and there is no other way to expose a screen in my shop. In fact we gave Dan our Vastex unit and gave away our Ameragraph MH unit.

[TCT]

Happy with our M&R Starlight. We use Diazo. We may be a "M&R Strong" shop, but I am not going to keep something that I am not happy with just for the sake of keeping it and there is no other way to expose a screen in my shop. In fact we gave Dan our Vastex unit and gave away our Ameragraph MH unit.

Very good point. I wasn't trying to start crap with the M&R Strong thing, it was just a observation.

[GraphicDisorder]

Happy with our M&R Starlight. We use Diazo. We may be a "M&R Strong" shop, but I am not going to keep something that I am not happy with just for the sake of keeping it and there is no other way to expose a screen in my shop. In fact we gave Dan our Vastex unit and gave away our Ameragraph MH unit.

Very good point. I wasn't trying to start crap with the M&R Strong thing, it was just a observation.

I get it. It always looks like its M&R Strong because of other reasons. I can tell you a little about me, the cost of a LED unit is a impulse buy for my business... if our LED unit wasn't doing its job we'd have another one, tomorrow. Just being truthful.

[siestasol]

Does anyone tried the CCI unit.  CCV2536 Around $5,500.

[kingscreen]

We love our Starlight.  Once the Kruzer that we sold is picked up, it will be the only piece of M&R equipment we will have.
We got it before the Workhorse unit came out, and from what I understand Workhorse has a new/updated version with more/different LEDs in them.

[Maff]

We got the Ryonet FX Exposure earlier this year and it's been really amazing for us.  Our screen making has become super reliable and consistent. It was well worth the money, I read too many bad reviews about the cheaper LED units. 
It's the same as the Saati Pro Lite 450. Saati makes the lamp, Ryonet makes the rest of the unit.   
405nm.  We use it with CryoCoat, (which i've heard rumors that emulsion is just PHU2 dyed green).
Vacumm draw down time 22 sec
Our standard expose time for general stuff is 5.5 sec. We get No slime on the inside of the screen ever.
We do a fair amount of 4CP and Sim Process and we expose halftones down to 3% at 55lpi on a 280 mesh.  The high end dots aren't as good yet, but i'm still tweaking our film positives.
When we are doing WB/DC we post expose for 30 sec and haven't had any break downs, but we are pretty small and a big run for us is 500 shirts, but even then no break down with DC.
The user interface on the app could use some more adjustments, but they are already on version 2.0 and that had a lot more improvements from the first version. What's nice about the app situation is it can always be updated and if anything were to ever go wrong with the tablet, you can use your phone. and in the absolute worse case scenario, there are manual buttons that operate the vacuum and lamp.

[T Shirt Farmer]

I had the Saati unit for a few months but returned it as the blanket often failed to make a good seal resulting in unusable screens. I tried to adjust per factory techs suggestion, moved the cotton rope all over the place but ultimately felt I had to baby sit it until the blanket drew tight when you should be able to press go and walk away.

[Maff]

I had the Saati unit for a few months but returned it as the blanket often failed to make a good seal resulting in unusable screens. I tried to adjust per factory techs suggestion, moved the cotton rope all over the place but ultimately felt I had to baby sit it until the blanket drew tight when you should be able to press go and walk away.

We had a similar problem with ours at first, it would take almost a 1 minute to draw down all the way. The inlet for the vacuum hose would get stuck to the glass and not draw down. We took the rope and made a bunch of knots around that inlet and taped it to the glass so the hose had plenty of room to breath, the rest of the rope goes onto the screen.  After that it was never an issue and we could hit go and walk away, 30 sec later the screen is done.
 
I will admit that really annoyed me though, simple engineering flaw on an expensive machine that could be easily fixed. I addressed it with one of their product development guys and they said they had some new modification in the works...

[im_mcguire]

Well Ill tell you about our Workhorse LED unit, since we are all sharing.
We got ours last month.  I know some people have had issues with it not doing dual cure emulsions.  They did have issues with their earlier incarnation of the unit from the jump as stated.  But they have made overall improvements starting this year.  They moved spacing from the glass from the LED's and if I was told correctly from their tech, they also improved the LEDs that go in the unit, or they added more (I cant remember exactly).

We use Murakami Aquasol HVP emulsion, and we have ran a plastisol job for 4500 double strokes (9,000 strokes) with no breakdown.  We burn at a 6 1/2 second burn time and it takes the vacuum about 10ish seconds to completely draw down.
I used Dan hlaftone test and I was getting solid 5% on a 180 s mesh with these settings.  I was pleasently surprised at all of the results I have gotten thus far for what I have needed it to do.

It works great with SP 1400 and Murakami T9 emulsions, and I know shops that use these emulsions for wb/dc and have no breakdowns.

For what its worth for anyone doing future research.

[Rockers]

Stay away from the Vastex unit. To hold fine detail is becoming an art in itself and I`m glad that we kept our MSP3140 for exposing halftone screens. Would not be able to do that with the Vastex unit. Support was rather vague too. "We can`t work out why the unit is not performing for you" was the reply. Now I l now from one board member here who had the same LED as us and was allowed to return it, not us though.