What kinds of drum fits in a GR 3770?

[fabeluna]

Hello,

I have bought a GR 3770 with a black color drum in it.
Now I look for three additional color drums, but I'm insecure with all the different types of it.

There are GR color drums with the addition "W", and drums without it.

In the GR-Manual there are five different sizes for the GR color Drums:
-Ledger size
-A3
-Legal size
-B4
-A4

Means the addition "W" "wide"? Is it a "A3" or a "ledger size" drum?
I think only the A3 and the Ledger size drums fit in my GR 3770?

An other question, that I don't really understand is, the thing with the HD ink: Means that a drum from a 3750 don't fit in my 3770, because it isn't a HD color drum?

I'm a little confused with all that various values..
Can anybody help?

[Iowatech]

Best as I can remember, HD only was for black drums, so color drums from a GR3750 should probably work.
As for the sizes, if the drum is rated for the GR3770 (or a color drum from the GR3750), it should be OK, but drums from GR2750s and the GR1700 series are too narrow to fit in your machine.
One thing to keep in mind - the GR line has been obsolete for some time, so there have been no new parts for your machine for quite a while. So take care when selecting other drums for your machine, as they could be already be worn out pieces of junk.
On a lighter note, if your machine works well, there's a pretty good chance it will work well for some time, the GR line was like that. And there is all sorts of information about adjustments for GRs already here in Digital Duplicators to help you keep the machine running for as long as possible.
Might not hurt to check here, too:
http://justmanuals.com/
If you have a decent mechanical aptitude, a service manual could save you the cost of a service call.

[ddude]

A color GR drum with "W" will fit in your GR3770- The "W" is for WIDE- A3 or 11x17, which is what your machine will run.

The GR3770 will need a HD black drum, this is how the machine was designed. While the color drums can be used between the GR3750 and the GR3700, along with FR3950s, an HD black drum is required in the GR3770.

[ddude]

AND- Did I mention that I have two new FR/GR (W) drums, still sealed in their box, available for sale?


ddigitaldude@hotmail.com

[fabeluna]

Hello,

thank you so much for the replies!
Great Forum!

Very good, so I don't worry about HD ink any more.
How can I see if the wide color drum is A3 or ledger size? Is there any other additional label?

I know, the GR line is obsolete, but the price was very good, so that was OK for me. I hope it will last for a while.
I will use the Riso mainly for experimental illustration printings, not really high numbers, but maybe higher numbers at later time.

I come from Germany, the shipping and tax charges from USA are very high.
Unfortunately only offers within Europe are really cost-effective to me..

[Iowatech]

I think the size might be stamped onto the metal drum body, the part that the master is wrapped around, but I might be thinking of a newer model.
If that is the case though, you should be able to see it on your machine's drum. There's a number stamped on the drum body that looks like this: NNN-NNNNN-NNN (your number will probably start with 017), it might be near there. If not, if you look that number up in the parts manual, it will tell you what size the drum is.
I've only worked on GR3770s with ledger sized drums, but I seem to remember that properly set up drums had stickers on the front showing the size and color, too. But how far you believe those stickers is equal to how much you trust the person you are buying the drum from. Caveat emptor, after all.

[fabeluna]

Hello Iowatech,

I will look for the number, thank you so much!

[risomat]

In the GR-Manual there are five different sizes for the GR color Drums:
-Ledger size
-A3
-Legal size
-B4
-A4

as far as we know:

RISOGRAPH GR Color Drum (W) = DIN A3 (420 × 297 cm) or 11 × 17 inch (aka ledger size)
RISOGRAPH GR Color Drum = DIN A4 (210 × 297 cm) or 8.5 × 14 inch (aka legal size)

B4 (250 × 353) fits into DIN A3


about black: you just need Black HD Ink and change the switches:

color drum (w) setting (us): R8 off, R9 off, R10 on, R11 off, R12 on, R13 off
color drum (w) setting (europe): R8 off, R9 off, R10 off, R11 off, R12 on, R13 off
black drum (w) setting (europe): R8 off, R9 off, R10 off, R11 off, R12 off, R13 on