sheetfed vs. web press

[NewJim]

What are the advantages and disadvantages of a web vs. sheetfed press?

 

[SM-Printer]

Sheetfed presses can handle a wider variety of stock thicknesses whereas web (roll-fed) presses generally print on thinner stocks -- if you're printing on cover weight stock, you're most likely looking at a sheetfed press.

Web presses are faster though and are generally used for longer job run lengths (25,000 + impressions). Whereas sheetfed presses can print up to 14,000 impressions per hour, web presses can print up to 40,000 impressions per hour!

 

[NewJim]

Thanks -- what limits a web press from printing short-run jobs? Is the per-job setup time noticeably more than for a sheetfed press? I imagine color to color registration would be better on a web-fed press than sheet-fed; is there any quality downside to a web press?

 

[AOD_Daggs]

I run a Didde ML2000 web press and we print 1 color and 2 color jobs that are anywhere from, 500-40,000 impressions. We use poly plates. I can hang plates and have it back up and running in under 2 minutes. If you are running 2 color and dont do a lot of color changes small runs are no big deal IMO on the Didde.

 

[xallux]

Where a web press loses against a sheet-fed is waste. I have run both web and sheet-fed so I can see the difference. Where I could make-ready a job on a sheet-fed in 300-500 sheets, on a web sometimes it takes 2000-4000 impressions to get everything settled down.

 

[rham]

I don't think the quality on a web press is as good as sheet fed mostly because of the paper. Only if the web press is ran on good paper and though a chiller to set the ink is the quality near as good. Also the register is better on a sheetfed especially since everyone now uses the computer to plate system CTP imho