LED Exposure unit first impressions. . .

[Screened Gear]

Hi everyone
I would 1st like to thank Pierre for taking the time out of his busy schedule to test the BJ2K, and confirm the unit’s performance for the people of this forum.
Pierre had so many tools for checking the quality of screen printing, that at one point I felt like he might be the Batman of screen printing.  “Where does he get all those wonderful toys?”

I now understand why he is so highly regarded!  The quality control of his product says it all!
You’re a great screen printer, but a better person. Thanks again Pierre, it was an honor to meet you.
Lou
www.LDTronix.com

Lou,

Nice work on that unit. I am glad to see it worked out with Pierre. So what your you going to do with all the money you get from the BJ2K???  Wait a min...BJ2K  Now thats an expensive BJ

Jon

[blue moon]

5 seconds seems too short to me. It leaves very little room for adjusting exposure time. I know sometimes if I am running low on screens and I am putting something on a 280 that should be on a 305 I may under expose slightly to make washout of the finer detail easier and then hit with a post expose. Can you set the time on this to 4.72 seconds if you want to do this?

Agreed! The latitude at such small numbers needs to be infractions of a second!

this was one of the things Lou and I discussed and will be implemented in the future. I have a feeling it is not a big deal and can be available right now, but he will have to confirm.

pierre

I was thinking with exposure times so short, and the typically small window of ideal time for some of the "fast" emulsions on the market, might an integrator of sorts that could be programmed to reduce the light output to allow for more fine tuning on an as-needed basis? I know it seems counterproductive, but with times like 5 seconds, going up to ten, or striking an ideal time somewhere in between might actually be more desirable. Can emulsion physically react positively to times in tenths and hundredths of a second if a timer capable of accurately cutting the light to those degrees were incorporated?

interesting point, I had to think about it for a second. . .
Yes, Lou and I talked about making changes to the timing and it is an option (it is already in the unit), but in the end my thinking was that it would be better to introduce fractions of a second than to prolong the times. It accomplishes the same without slowing down the process.

interesting part is, there is no need for an integrator. From what I understand, LED's don't dim with time so the amount of UV light you get in 5 seconds now should be exactly the same 20 years from now. The main purpose of the integrator is to compensate for the lower light output and since it is not happening here, it is not needed!

pierre

[DannyGruninger]

I can just see it now, us retrofitting this technology to go right on our CTS unit. There's certainly room for the led light tubes to fit under the screen on our unit. It would be as simple as image the screen with the cts printer, flip the screen around, hit a button and 5 seconds later you would have a fully exposed screen. On the 3 head cts units like lawson and m&r that can do a full size image in around 30 seconds, plus 5 sec expose time that would be a super fast combination. If you could image and expose 1 screen in 45 sec that would means in theory we could do 80 screens in 60 minutes.....Oh no, I didn't just go there did I?   

[ScreenPrinter123]

Guys guys you're going about this all the wrong way. There's an easy solution. We all come together and order the same dts/cts unit - that way it's in bulk with a major discount - and they have to have the LEDs installed on the machine. Maybe they'll even splurge and get frog's machine painted green. What say you rich? :-)

[Admiral]

is it possible to remove the glass and expose CTS imaged screens on this?

[mk162]

anything is possible.

Also, here is a concern...how are the bulb strips assembled, can a single bulb be replaced?  Or do you have to replace the entire strip?  What does a replacement strip run?

I know, bulbs are rated for 50,000 to 100,000 hours, but have you ever seen an LED traffic signal with every bulb working?

[LDTRONIX]

anything is possible.

Also, here is a concern...how are the bulb strips assembled, can a single bulb be replaced?  Or do you have to replace the entire strip?  What does a replacement strip run?

I know, bulbs are rated for 50,000 to 100,000 hours, but have you ever seen an LED traffic signal with every bulb working?

In the unlikely case of failure you would call me.

I will overnight the failed part to you.. 
The M.L.B. strips are modular, and can be simply replaced. 

Note: Technically the unit will still function, until the strip gets to you.

[LDTRONIX]

is it possible to remove the glass and expose CTS imaged screens on this?

I have to do a little testing, but I think CTS screens will not be a problem. Just an option.


Stay tuned

[LDTRONIX]

Lou,

Nice work on that unit. I am glad to see it worked out with Pierre. So what your you going to do with all the money you get from the BJ2K???  Wait a min...BJ2K  Now thats an expensive BJ

Jon
[/quote]

This is just the Baby j2k,  I have allot of ideas in other areas of this field.
 
I can see a really large family of really hard to imagine products in the near future.

[StuJohnston]

Ok, how about uv ink curing units? Nazdar has developed an ink system or systems that are tailor made for LED curing, but are sort of hush hush about it. When I talked to the Nazdar rep about it, he said something about only selling to companies that have the R&D to make the curing unit. So far as I have been able to find, no one has come out with a commercial solution yet and it seems like it would be no more difficult to do than what you did with this BJ machine. Well, I guess a radiometer might be necessary.

[LDTRONIX]

UV ink sounds like a great idea to me!

[pwalsh]

Ok, how about uv ink curing units? Nazdar has developed an ink system or systems that are tailor made for LED curing, but are sort of hush hush about it. When I talked to the Nazdar rep about it, he said something about only selling to companies that have the R&D to make the curing unit. So far as I have been able to find, no one has come out with a commercial solution yet and it seems like it would be no more difficult to do than what you did with this BJ machine. Well, I guess a radiometer might be necessary.

Stu:  Thanks for sharing the news on Nazdar’s LED UV curable inks.  Nazdar has been manufacturing inks that cure with LED UV energy for the past couple of years and selling these products to a limited number of customers who are printing small format graphics such as roll-to-roll labels, container decorating and some industrial applications.  The major hang up against these inks being more widely adopted for general graphics applications has been the lack of availability and the prohibitively high cost for large format UV LED curing units.  EFI VUTEk is another company that is taking a leadership position with using UV LED cuing on their large format digital inkjet printers.  The advantage that a digital press has is that the curing unit scans over the entire image with the print head carriage so they only need a small format curing array.

I do want to dispel one rumor about Nazdar keeping these products “hush-hush” by reminding everyone that we partnered with M&R to demonstrate our LED UV curable inks on a modified M&R inline press at the last SGIA show in Las Vegas, and even participated in a television interview at one of our customers in the upper Midwest, so you can be assured that the inks are not a secret.  http://youtu.be/rrnD63LAp6g The bottom line is that Nazdar is ready and waiting with a range of LED UV curable inks just as soon as the rest of the industry to include the equipment manufacturers, screen and digital inkjet printers are ready to go in this new direction. 

[StuJohnston]

That's great to hear! I was mainly going off of the frustration of seeing the inks advertised on the Nazdar site, even though they weren't available through sourceone or anywhere else so far as I could tell. I did some research into the machinery and it looks like the basic parts are available, such as preassembled banks of high uv producing LEDs. I understand wanting to wait until there is a widely available solution to release these into the wild. Thanks for the update I am really interested ink where this goes!