2 exposure units on eBay

[Denis Kolar]

http://www.ebay.com/itm/NuArc-26-1K-Plate-Imaging-plate-burner-23-x-27-NICE-/370545340219
http://www.ebay.com/itm/NuArc-26-1K-Mercury-Exposure-System-/260861505994

If someone needs exposure unit, this is a lot better than building one yourself.
I have 40-1K and I like it a lot (it can take a bigger screen than 26-1K can).

[Frog]

Platemaking exposure units will require extensive modification to take a screen frame. However, can certainly be scavenged for parts if the price is low enough.

[Denis Kolar]

Andy, that is a good point. I did not noticed that the top one is a plate maker.
For the bottom one, I would contact the seller.

These units were made as a screen printing exposure unit and also as a plate makers. I think that the only difference is a vacuum blanket. (I think)
When I contacted M&R, they wanted to see the picture of it before they would give me instructions, just to make sure it is the one for screen printing.

[blue moon]

Andy, that is a good point. I did not noticed that the top one is a plate maker.
For the bottom one, I would contact the seller.

These units were made as a screen printing exposure unit and also as a plate makers. I think that the only difference is a vacuum blanket. (I think)
When I contacted M&R, they wanted to see the picture of it before they would give me instructions, just to make sure it is the one for screen printing.

the second one supposedly has Mercury bulb rather then metal halide. 'not a good choice for parts either. . .

pierre

[Denis Kolar]

the second one supposedly has Mercury bulb rather then metal halide. 'not a good choice for parts either. . .

pierre

Both of them are Mercury. Bulbs can be bought on eBay, between $40 and $100.
I got the new bulb and I kept the old one as a back-up.

[blue moon]

the second one supposedly has Mercury bulb rather then metal halide. 'not a good choice for parts either. . .

pierre

Both of them are Mercury. Bulbs can be bought on eBay, between $40 and $100.
I got the new bulb and I kept the old one as a back-up.

I thought your unit was Metal Halide? Mercury units are not recommended from what I understand. . .

[Denis Kolar]

I thought your unit was Metal Halide? Mercury units are not recommended from what I understand. . .

Nope, it is Mercury.
As far as I understood them, the only difference is that Mercury bulbs do not emit as much UV rays and that is why they are a bit slower exposure units.
Also, Mercury is liquid metal that emits radiation (I do not think that bulb or two will matter or will kill you ).

[JBLUE]

I thought your unit was Metal Halide? Mercury units are not recommended from what I understand. . .

Nope, it is Mercury.
As far as I understood them, the only difference is that Mercury bulbs do not emit as much UV rays and that is why they are a bit slower exposure units.
Also, Mercury is liquid metal that emits radiation (I do not think that bulb or two will matter or will kill you ).

Well at least when you have exposure problems you will know what is causing it.....

[RonH]

I thought your unit was Metal Halide? Mercury units are not recommended from what I understand. . .

Nope, it is Mercury.
As far as I understood them, the only difference is that Mercury bulbs do not emit as much UV rays and that is why they are a bit slower exposure units.
Also, Mercury is liquid metal that emits radiation (I do not think that bulb or two will matter or will kill you ).

Well at least when you have exposure problems you will know what is causing it.....

The Mercury Vapor lamps were very popular up until the early 90's when the emulsions were changed to be more environmentally friendly.  When that change was introduced everything started shifting toward the Metal Halide.  The Metal Halide is better and faster for most all of the emulsions because it matches the spectral requirement of the emulsion.   The difference is in the spectral output of the lamp. 

The 26-1K and the 40-1K table top units were originally designed for Litho and we did have a Screen Print version.   The 26-1K Litho model was so popular that there were times when we were shipping over 200 units a month.  So you can see why there are so many of those still around.Litho units are designed to hold a thin metal plate and a film negative so the total thickness of the substrate being exposed must be a quarter of an inch or less.  Obviously these units will not handle a Screen Frame.   The base underneath the blanket was made totally different, so it is not just changing out the blanket.  To turn a Litho unit into a Screen Print model would definitely be a DIY project. 

Ron Hopkins
Domestic NuArc Sales Mgr.
M&R Sales and Service Co.

[ebscreen]

Thanks for the info Ron!

Quick question, are mercury vapor bulbs more suited for diazo based emulsions?
I'd assume that's the "emulsion of yore" you're referring to.

If so, one of these might make a decent project for waterbased printers that
don't like the time it takes (tying up exposure unit) to expose diazo based emulsions.

[Denis Kolar]

I was exposing dual cure and now I use Chroma Blue pure photopolimer emulsion. As far as I know, no issues except that it takes a bit longer.
Brad, mk162 has the same unit as me, and have been using it for a while.

[RonH]

I was exposing dual cure and now I use Chroma Blue pure photopolimer emulsion. As far as I know, no issues except that it takes a bit longer.
Brad, mk162 has the same unit as me, and have been using it for a while.

We replaced the Mercury Vapor units around 1995 with the Metal Halide units.  Obviously the emulsions have changed a lot since we last used  Mercury Vapor lamps.  The GW114 Mercury Vapor lamp had much narrower peaks in the spectral output ranges as compared to the current Metal Halide lamps.  The current lamp is what we call a Multi-Spectrum lamp because it outputs light to cover both the area formally covered by the Mercury lamps and the Metal Halide lamps.  We dope these lamps so that we are covering the needs of both the Diazo and Photopolymer emulsions.  Since we have not manufactured Mercury Vapor units in the past 15 years, there has been no reason to test the earlier Mercury units to get a comparison.  The newer lamps are covering a much wider spectral area, which gives you more latitude to change emulsions.