Amergraph V28-1200 for Photopolymer Questions

Hi all,

I just acquired an Amergraph V28-1200. It’s an older model with an analog integrator. I’m wondering if anyone out there knows if this would be suitable for exposing photopolymer and roughly what I should be setting this to when I try my first test strips.

Also, its a 120v unit but has a plug with one perpendicular pin on it. Could I lob this off and put a standard US 3 prong plug on it?



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The perpendicular pin on the plug is to fit a 20 amp outlet. You could lop off the 20 amp plug and replace it with a 15 amp plug, but the thing probably has a 20 A plug installed because it needs a 20 A circuit.

Thank you Keelan,

Should this be fitted to its own dedicated breaker as well? I’m having a new subpanel installed so perhaps I’ll just install the proper outlet instead starting any surgery.

Never cut anything off your cords… there made that way for a reason. Your asking for a fire hazard.


You can put more than one thing on a 20A circuit, so you wouldn’t need a dedicated circuit… Actually, most 20A outlets have a T slot, so that you can plug 15A and 20A plugs in to them. If you’re in the midst of electrical upgrades, it would make sense to have everything wired with 20A T slot outlets (it local codes permit). It would cost more, but the upshot is that you’d have heavier gauge wire inside your walls. You can’t swap the breakers and outlets on an existing 15A circuit for 20A breakers and outlets, though, the existing wire (most likely 14ga) isn’t up to the job. I am not al electrician, but I will provide you with a grain of salt, if you can send me your mailing address.

If you examine the area of the electrical cord’s attachment to the device you should find a plate with the electrical specifications — required voltage, current draw, frequency, etc. As an example it might say “120VAC, 60Hz, 20A, 2400W”, which tells you it requires 120V at 60 cycles per second, draws a maximum of 20 Amps in operation, which multiplied by 120 Volts gives a power draw of 2400 Watts. Normally the maximum current draw is at startup, but for safety the circuit you connect to should have that capacity. Connected to a normal 15 Amp circuit it would almost certainly blow the fuse or trip the breaker.


This machine requires a dedicated line. I have had one for years. You can use it with something else on the line, but it is not suggested. Reason being, has something to do with the “draw” of electricity (volts or amps) I’d have to get my manual out and look it up. Check with Amergraph. If you think I’m not right. Also, I have not tried making plates pp plates with this. I’m sure it would image the plate, but to the right specs..??

Winfred Reed
Black Diamond Press (Kentucky)

The Amergraph V28-1200 uses mercury vapor lamps and is intended for exposing offset plates and daylight-safe contact film and paper. It’s probably not practical for exposing photopolymer plate material. Amerigraph also makes UV light exposure units that are intended for screen printing - those would likely be a better choice for photopolymer.


Thanks so much everybody,

I’m in the midst of renovating so I might as well do it right the first time if I’m gonna do it at all. I’ll have the electrician read over what has been said here. Once again, thanks!

As for photopolymer exposing, I’ve found a few websites selling the 10431 amergraph bulb marked as a “photopolymer” bulb. They are still diazo bulbs with a range of 350NM-370NM but I’ve read that photopolymer UV light needs to peak around 410NM for ideal results.

Experimenting with this idea of mine will become costly quickly…

Hi all,

Its been quite some time since I posted my initial question so I figured it was due time for an update.

After many weeks of researching into the physics of UV light and the various methods of platemaking I’m more than happy to say that it worked. In fact, it worked very well.

I threw in a 20amp breaker and outlet to my main breaker box without issue and the platemaker worked fine.

Put simply, by replacing the Amergraph’s diazo bulb with a photopolymer bulb and using a Stouffer gauge I was able to expose a KF95 plate nicely with an integrator setting of around 2.5.

I ordered the Boxcar Press photopolymer offcuts and have successfully printed a number of projects using my homebrew plates. Mind you, the plates have no shoulder despite attempting to use kreen directly under the Amergraph’s glass and small serif type requires a lot more attention and sensitivity when exposing.

My film negatives are made professionally by a graphics place in my town so there is no experimentation with that aspect.

I will most likely refrain from using the photopolymer for type under 12pt. but illustrations and large type printed with impression very very well.

I’ll return with some example images of both the plates and the printed image. My eyes were sore from staring through that lupe in pure disbelief that it had actually worked.

Thanks to everyone who commented with their expertise. I greatly appreciate the help and support.