3800 rear feed skewing on exit

[evonzz]

recently when trying to print using the rear feed on my Epson 3800, the paper is skewing as it is printing the last few centimetres, thus ruining the print and wasting another sheet of paper.

i am using hahnemuhle bamboo A4 and it is happening on almost every print.  
There is also a build up of ink that covers the rear edge of the paper creating an unsightly blotch on an untrimmed print.

Could this be a platen gap issue?  maybe too wide?

Any suggestions gratefully received.

Cheers
Rodney

[Conner999]

I've seen similar things with some other papers on my 3800.

It sounds as if one rear edge of the paper is getting hung on something in the feed system (God knows there are enough bits to hang on if a paper is so inclined) or making slight head contact (ink smudge on paper edge) and acting as a 'brake'. One side hangs slightly, the other side of the paper continues to try to continue fwd, paper skews. Even the SLIGHTEST touch on one edge could cause a skew. The whole printing process is based on the assumptions that the paper in the feed area is a) flat,  not changing thickness(swelling) and c) feeding straight and evenly.  

It could be as simple as platen gap (I always err on wider than called  for side), but if there is ANY curl, I mean ANY, on the trailing or leading edge of a paper (Fine Art Baryta anyone?), it can cause issues. Throw in a platen gap that may not allow much margin of error and away you go.

The 38xx, lacking vacuum hold-down, doesn't play well with papers that aren't flat and/or swell under ink load. Curl on trailing edge SEEMS more sensitive. My guess is that as the bulk of teh sheet leaves the out feed slot and dips slightly to contact the tray, the trailing edge tries to lift - making a slight curl a larger issue.

Try a different paper - something generic and simple - a basic Epson paper that uses PK ink (Bamboo is PK IIRC) and if no issues, you now know it's paper specific. In that case, I'd suggest trying any or all of the following:

-Check for edge curl and if any, see if you can get rid of it.
-Open up the gap - you can go much wider than called for and would need a strong loupe and a very high-def paper to see any difference
-Try supporting the printed area of the sheet as it emerges from the outfeed.

I love the 3800 when it works well, but when you look at the myriad of issues we continue to have (in varying degrees) across ALL makes of printers, new and old, with scratches, paper handling, clogs, ICC's not taking, having the temerity to use non-MFG papers, etc., etc., and bloody etc., you can't help but realize why so many out-source their prints.

[Alan Goldhammer]

Interesting since I was talking about this exact issue at dinner with Mark Segal yesterday (he's down here in the DC area on business/pleasure).  Bamboo, even if you store it flat) is prone to curling at the corners and long edges.  I've found that I need to carefully roll it against the coated side using an acid free sheet to prevent scuffing of the surface.  If it does have a little bit of curl you can get exactly what has happened to you.  I don't think with matte papers you have the same issue with paper swelling relative to the glossy papers as the absorption rate of the ink is much faster and the fact that the coating of the glossy papers has a different physical chemistry in regard to its behavior.  Try examining the paper before you put it in to see what the curl looks like (this is one of the reasons I like Museo Portfolio Rag better than the Hahnemuhle papers; it is stiffer and quite resistant to curling).  

Hope this helps.

Alan

[Randy Carone]

+1 on Conner's suggestion to support the paper as it exits so it doesn't curl down before it rests fully on the paper tray. As the trailing edge comes forward it can lift slightly from the curl of the large portion of paper that has already exited the printer. I use a tall, narrow book or empty paper box that is just the height I need and not too heavy.

[evonzz]

+1 on Conner's suggestion to support the paper as it exits so it doesn't curl down before it rests fully on the paper tray. As the trailing edge comes forward it can lift slightly from the curl of the large portion of paper that has already exited the printer. I use a tall, narrow book or empty paper box that is just the height I need and not too heavy.

All noted. thanks.

Will examine paper carefully next time.  One concern i have, and it could be a possibility with this machine, is that there is a build up of ink or general pollutants / dust / crap in the rear slot.

I will try to get some Epson cleaning sheets, but any other suggestions?

Cheers
RE