Ricoh C901; PTR Shock

[jinthebay]

The printing company that I work for purchased a Ricoh C901 about four months ago. We had been running an Indigo series 2 press but decided to look for an alternative due to the high cost of the impression count customer charges as well as the fact that these series 2 presses will no longer be supported as of later this year.

The Ricoh has shown both it's strengths and weaknesses and overall, we are pleased with the results. There are things that the Ricoh can do that the Indigo couldn't and vice versa.

One of the main reasons we went with the Ricoh was (supposedly) it's ability to run 14pt and 16pt stock. Many of our existing customers have expressed their interest in heavier stocks for postcards and business cards and our Indigo was unable to print on anything heavier than 12pt. However, what we've come to find with the Ricoh is what our tech is referring to as PTR Shock. As the sheet is traveling through the fuser, vibration is causing a visible band to appear across the sheet, from operator side to service side, and this is caused by it's weight. Apparently, the extra weight makes the sheet unstable enough so that the toner can't adhere to the paper in that certain area, We don't see this in our lighter weight stocks. The tech was in a couple of weeks ago to make some adjustments and some tweaks but to no avail. Anyone ever come across this phenomenon with either a Ricoh or other machine in it's class?

 

[mwc]

Have not seen this. Only time I had an issue was with a 100# Cover Satin stock, where toner was not covering properly about .0625" from the short edge of a 12x18 sheet...tech made some adjustments for that particular stock and resolved the issue.
We have run 14 - 16 pt, or 130# cover without incident (we make sure that it is 350gsm or lighter, as machine spec states)
Heavy stock from larger trays (#3 mostly, or tray #4)
It might be an issue with your particular stock & finish that needs some per paper adjustments? I know there are adjustments that can be made to speed up/slow down the sheet entering the fuser, as well as fusing power adjustments for top or bottom of sheet. (possibly ask Ricoh for a list of stocks they have validated for your finish & weight)
I know we have used 130# Blazer Cover-Gloss and some Endurance of the same weight w/o problems.

 

[jinthebay]

Thanks MWC. I will try to find out more about the stock alternatives. One thing to note. It almost seems worse on a shorter sheet as there is less flex. In other words, the banding is less noticeable on a 13x19 sheet as opposed to a 11.5x17.5 sheet. If that makes any sense.

 

[jinthebay]

Hey MWC. Just a follow up. We brought in a digital 16pt. C2S, specifically TANGO and it ran very well. Still some very minor banding and hints of the PTR shock but no jamming and certainly a HUGE improvement. I think pre cut digital is the way to go for us from now on, it least in the heavier stocks that gave us trouble. I'll post again if I have anything to add to this post. Thanks again.