Starlight UV LED Exposure

[Mr Tees!!]

...so in another thread there have been some questions about diazo emulsions, and waterbase/discharge. We have burned a dozen or so screens with our Starlight and I can post some findings!

...Our unit is made to burn a single 23x31 at a time. Vacuum drawdown does seem to be around 10 seconds, you can easily tell when its done.

...we use CCI WR14 emulsion, which is the faster replacement for WR25. With our previous unit (flo-tube), WR25 exposed at about 3:30-4:00, and when we switched to WR14, we did see exposure time drop to 2:30.
   With the Starlight and WR14 emulsion, we have burned our screens as low as 15 sec and as long as 25 sec! I think we may settle on high mesh counts at 20sec, and lower mesh counts at 25sec. At these speeds, the mesh color seems to make a difference, too, so I think we will test all white mesh at 25 sec to be safe. Images are just as sharp (if not sharper) than our FL unit would produce. And I do seem to notice the screens seem to be burned more "thoroughly", for lack of a better term....by that I mean there is less noticeable interference from areas covered by the milky-clear blanks film areas vs areas of no film at all.

...we do not do much WB/DC, so I cant speak much of the durability factor of that. But the unit and the technology benefits us in ways that WE need it to:...

  -Much shorter exposure time. In fact, I fount that by the time I pulled the film off of a freshly exposed screen and removed the tape from it, the next one was already done! So when I burned eight screens this morning, I just burned them all in a row and then washed/developed them all in a row.

  -Power savings. I had my previous unit on the same electrical line as the dehumidifier, and running the two simultaneously would always trip the 20A breaker. This has not happened since, so I know its drawing less power (I couldn't find a spec plate for comparison anywhere on our FL unit, which was made by a company called SPEC). But I also know that the fact it runs a fraction of the time our old one did HAS to contribute to power saving. PLUS the labor savings in keeping me from walking across the whole shop to reset the damn breaker once a day...

   -No heat. Even with a dehumidifier, its gets muggy and hot here in Americas Armpit. with the FL unit, films would start sticking to the screens after about five exposures, at which point the glass got hot. This glass will not get hot!

   -Consistency. Knowing that the lamps will FAR outlive me and my shop means that I don't have to replace them, which can be expensive on some MH units. and the fact they don't degrade for such a long time means I don't hafta constantly watch how long things are burning. Set and forget!

...So for our situation, this is looking like the golden icket thus far. I will keep posting results as we go along, and hopefully get a DC run here at some point!

SIDE THOUGHT: Rich, do you think this is going to essentially end the need for MH units? Will you continue to produce them? I was thinking about this over the weekend. If the price for LED is comparable or better, and with all the seeming benefits, is there still a need for any other type in the future?

[abchung]

@Mr Tee,
Thanks for the thorough review.

[Parker 1]

Thanks for the review.

Does/will M&R make a unit for larger screens?  25x36

[244]

Thanks for the review.

Does/will M&R make a unit for larger screens?  25x36

Yes. It's called the Star Light 3140

[Gabe]

Yo@Mistertees in addition to power savings, burning time etc.
How much quietter is this new toy compare to the spec unit?

[Mr Tees!!]

...SHORT ANSWER: yes much quieter tan what we had.

...LONG(ish) ANSWER: This question prompted me to do a little research, and I found an Android app that measures sound pressure in decibels, neat! I will try to run them both and report back with just how much quieter the Starlight is.

[jvanick]

so it's been roughly 2 months since the last post..

has anyone gotten one of these yet that's run a longish discharge run on it?

and/or held some really detailed halftones?

we're in MAJOR need of a 'real' exposure unit here, and I'm thinking that this is just the ticket...

(unless somebody is getting rid of a decent MH unit in the midwest for 2k or less shipped (or picked up if close enough)

Rich: what kind of lead times are on the single 23x31 units right now?

[244]

Delivery is currently 3 weeks

[abchung]

How well can the Starlight expose in the detail/process category?
(e.g 55lpi: 5%,10%,15%).

Thanks
Anthony

[244]

How well can the Starlight expose in the detail/process category?
(e.g 55lpi: 5%,10%,15%).

Thanks
Anthony

You will find no difference in quality from our MSP3140 which is a very good unit. Holding a 2% dot @55lpi will be no problem.

[Mr Tees!!]

...we went from a fluo-tube unit to the Starlight, so I cannot speak to how exposure results may compare to a MH unit. I DO know we are now getting the same, if not better, results in a fraction of the time and using a fraction of the energy, which is exactly what we set out to improve on.

...we don't do much detail-oriented stuff, mostly bread-and-butter vector work. We usually set halftone dots at 50-40 lpi, depending on ink used and other variables. I can say that, last week, we exposed a 10% dot across a large area on a 200mesh with no moire at all.

...I would trust Rich here, I know he had a high-level industry guru come in specifically to test various emusions and exposure times.

[abchung]

Thanks for the info Mr Tee and 244

[T Shirt Farmer]

Does this unit have the ability to store pre set exposure times
Can it set delay for blanket draw down before exposure,
Is the vacuum pump part of the cabinet or does it live on the floor next to the machine

[244]

Does this unit have the ability to store pre set exposure times
Can it set delay for blanket draw down before exposure,
Is the vacuum pump part of the cabinet or does it live on the floor next to the machine

The questions all relate to what you knew as the methology to expose screens in the past. You set the vacuum at 15 seconds and forget about it. There will be no need to change it as you will have full vacuum that is extremely quite by then . No need to delay before you start exposing this way. If the unit is on the stand the pump is bolted to the shelf on the leg. A change of exposure time from the one you have already set takes less than a second or two so no need for storing something you would waste more time looking for. Most users of the Starlight are not seeing much reason to be changing the amount of time the unit exposes. Some user may tell you about this.

[T Shirt Farmer]

Great.. placing my order this week, whats ETA?