Vastex entering world of LED exposure units

[Gabe]

Has LED exposure been tested on long run discharge screens? 

I think is to early to tell the new LEDs exposure is still
in it`s infancy, eventually

[ScreenPrinter123]

Has LED exposure been tested on long run discharge screens?

You would hope so; otherwise, a manufacture blazing this new trail would be spinning its wheels given the rise of discharge usage. That would be a great question to ask vastex and report back about, unless someone reading this thread from vastex is reading this -- what are the exposure times on dual cure/diazo emulsions?  Surely with such a new method, buttloads of testing on every emulsion on the market should be tested, which reverses the usual way you get an estimate of exposure time with the emulsion manufacturers rather than the exposure unit manufacturers putting that valuable info in their product literature.

[Binkspot]

I really do not see where the diffrence would be with types of emulsion. UV is UV, the LED's are still producing a UV wave length and from what I understand its more concentrated and evenly emitted. As long as the source is emitting the correct wave length (360-380 nm if I remember correctly) it shouldn't make a diffrence. Keep in mind we can not see the UV spectrum of light but relate the blue hue of our exposure units, we see the blue hue and assume its exposing. The light we see exposing is simply a by product of the bulb producing the UV. We do not burn photopolymer on a different exposure unit then we would diazo. 

[ZooCity]

I really do not see where the diffrence would be with types of emulsion. UV is UV

My thoughts exactly.  Just not sure if there's some spectral (and power within each wavelength) differences btwn what the LEDs can do and metal halide.  Having ran so much discharge, it would no surprise me at all if this was an issue- everything becomes a potential problem with DC it seems.

like 123 mentions, this is flipping the R&D schedule around.  Many emulsions were formulated to expose on fluoro or metal halide lamps.  Now we have lamps being tuned to existing emulsion. 

If somebody really wanted to kill it with an LED expo unit, they would work alongside an emulsion mfg and make a companion emulsion to their bulbs.

[Binkspot]

If I remember correctly talking to the Saati people a few months ago the engineers said they had developed there own LED insert to convert existing tube type exposure units working with their product line. I think I may have a brochure on it at the shop.

[LDTRONIX]

Hey Guys long time no post!

Thanks for all the support, and kind words!

I see the cat is out of the bag about the new Vastex machine!

Take it from me this exposure unit is the cats meow.   
I know because it is powered by LDTronix.

Look at the bottom left corner of the E2000
http://www.vastex.com/Literature/BB-0826_LED.pdf


Vastex is a great company, and I am proud to work with them on this and future products. 

I hope to release more great products in the near future.  So stay tuned

Thanks to the great people of this forum!

LDTRONIX

[ScreenPrinter123]

I really do not see where the diffrence would be with types of emulsion. UV is UV, the LED's are still producing a UV wave length and from what I understand its more concentrated and evenly emitted. As long as the source is emitting the correct wave length (360-380 nm if I remember correctly) it shouldn't make a diffrence. Keep in mind we can not see the UV spectrum of light but relate the blue hue of our exposure units, we see the blue hue and assume its exposing. The light we see exposing is simply a by product of the bulb producing the UV. We do not burn photopolymer on a different exposure unit then we would diazo.

What I'm getting at is so what if the unit can properly expose a pp emulsion. If it can't expose a dual cure/diazo emulsion in a non-time-prohibitive length of time, its not worth getting over the 5k+ watt halide units.  And by "properly expose" I mean quickly expose a du cure/diazo much quicker than those 5k units and still get the same durability results on large dc jobs.

[ScreenFoo]

I've read more than a few articles like this: 
http://www.nxtbook.com/nxtbooks/STMG/sp_20131201/index.php?startid=8

Unfortunately, I have no laboratory to confirm these results, but I believe different sensitizers do in fact expose better with the proper spectral output...

[blue moon]

from what I understand, PP/SBQ and Diazo link at different UV wavelengths. While it might be possible to have the UV LED bulbs peak at the correct number for the PP/SBQ and produce a very small amount of the light needed for the Diazo, it is not very likely to be the case.

Lou, do you have anybody using the unit with dual cure or Diazo emulsion? Can we get some feedback on how it works with it? Did Vastex test it with Diazo? You mentioned they were getting spectacular results with it. Was it with PP/SBQ only?

pierre

[blue moon]

I've read more than a few articles like this: 
http://www.nxtbook.com/nxtbooks/STMG/sp_20131201/index.php?startid=8

Unfortunately, I have no laboratory to confirm these results, but I believe different sensitizers do in fact expose better with the proper spectral output...

great article to demonstrate the potential issues. As mentioned above, it looks like one emulsion likes mid 300s and the other is around 400. Even if the bulbs have a rather narrow band of light, it would still expose correctly, it is just that the sensitivity and penetration of the emulsion are less suited for the bulbs with different wavelength and would thus take longer.

pierre

[ZooCity]

So pricing on the LED units from Lawson is competitive with similar halide bulb units.  Sounds like this definitely is the way to go if you are buying new.

For replacing our existing unit, hard to justify it.  To replace our halide setup with LED would run appx 8k. It would take awhile to see an ROI, even with the reduction in power consumption.  We have two functional Olec AL53 units in the house and many can still be had for a few hundred dollars so I'm not sure if that day will ever come here.   

Saati has a drop in LED bulb for halide lamps?  Might be interested in going that route at some point.

[Rockers]

Here are the prices
Vastex
"The LED upgrade for metal halide units is not really an option at this time.  The mounting is an unknown and controls will not work.
 
In terms of the complete unit, the 23” x 31” unit is: $4,600 UD + shipping and the 47” x 31” is $7900 USD + shipping"


The Lawson LED-5000 #3248 is $3,695.00 which as far as I can remember is the medium sized unit, which will hold a tri loc frame.

[Rockers]

Oh and here are the exposure times

Real-Life Exposure Times using the LED-5000:
Lawson SBQ-501 Emulsion on 110 mesh with 1 + 1 coating method: 12 seconds
Lawson Dual-Cure-510 Emulsion on 110 mesh with 1 + 1 coating method: 35 seconds
Ulano EX-Film 50 micron on 110 mesh: 25 seconds

[Vastex]

Hey everybody. We're glad to see all of the conversation on exposing with LED so I'll chime in a little bit. We have done a lot of testing on our new E-2000 before releasing it and have compared it with a 1200W metal halide and high output fluorescent tubes.

We used Ulano (Orange and TLX) along with Kiwo (Polycol Onecoat and SWR Red) during our tests. We have also tested Kiwo Polycol Onecoat with diazo added to make the stencil waterproof for discharge inks. We used a Kiwo exposure calculator to get precise times. We also use the glisten method (3 coats shirt side and 2 coats ink side) of coating screens which give a much better stencil that 1/1. I'm not sure about testing a dual-cure on a 110 mesh as Lawson tested because most screen printers would be using a much higher mesh for that. Our dual cure tests were on 230 and 305 with the 305 easily holding 85lpi halftones and very readable 3pt text.

Our times were comparable and often quicker than the 1200W metal halide with better detail and 5-10 times faster than fluorescent on dual cure and about 15-20 times faster on single part emulsion. If anybody will be at the Printwear show in Long Beach this weekend, head over to our booth and check out the unit. We will also be printing a 4 color process (Kiwo SWR Red on 305 mesh) and a discharge print (Polycol onecoat with diazo on 156) all exposed on the new E-2000.

[Gabe]

Hey everybody. We're glad to see all of the conversation on exposing with LED so I'll chime in a little bit. We have done a lot of testing on our new E-2000 before releasing it and have compared it with a 1200W metal halide and high output fluorescent tubes.

We used Ulano (Orange and TLX) along with Kiwo (Polycol Onecoat and SWR Red) during our tests. We have also tested Kiwo Polycol Onecoat with diazo added to make the stencil waterproof for discharge inks. We used a Kiwo exposure calculator to get precise times. We also use the glisten method (3 coats shirt side and 2 coats ink side) of coating screens which give a much better stencil that 1/1. I'm not sure about testing a dual-cure on a 110 mesh as Lawson tested because most screen printers would be using a much higher mesh for that. Our dual cure tests were on 230 and 305 with the 305 easily holding 85lpi halftones and very readable 3pt text.

Our times were comparable and often quicker than the 1200W metal halide with better detail and 5-10 times faster than fluorescent on dual cure and about 15-20 times faster on single part emulsion. If anybody will be at the Printwear show in Long Beach this weekend, head over to our booth and check out the unit. We will also be printing a 4 color process (Kiwo SWR Red on 305 mesh) and a discharge print (Polycol onecoat with diazo on 156) all exposed on the new E-2000.

Thanks for stopping by Vastex boy
if there is not too much to ask, for those who can`t make it to the show
could you shoot a short vid of the new exposure unit
thanks welcome to TSB