multi-pass printing

[William35401]

is anyone familiar with a way to modify an inkjet printer so that multi-pass printing can be done on the same sheet of paper that will preserve the registration of the multiple images accurately? something like is described here with registration pins? -- http://amd.uwe.ac.uk/cfpr/index.asp?pageid=1660 . thanks. William

 

[ghwellsjr]

On my Canon MP760 (which is identical as far as printing goes to the much more popular MP780), I placed one sheet of paper in the rear Auto Sheet Feeder and printed the nozzle check. I retrieved the paper and put it back in the ASF and printed the nozzle check again for a total of five times. It was perfectly registered.

These older printers have sensors in them and a pair of rollers on either side of the paper so that if it is fed into the printer at an angle, it will adjust it so that it is going straight in. I purposely tried this with a sheet of paper that was as crooked as I could make it and the printer fed it inside, backed it up, straightened it out, and then proceeded to do the nozzle check.

Just for the fun of it, I took a fresh piece of paper and trimmed one edge in my paper cutter so that the leading edge was on an angle. Then I fed it into the printer and did a nozzle check. The printer moved the paper in and out and proceeded to print the nozzle check on an angle with respect to the sides and bottom of the page but perfectly aligned to the top (leading edge) of the page. It almost jammed in the printer though because the page wasn't rectangular.

Now this won't correct the side to side offsets but if you adjust the guide for the correct width of the paper, you won't have that problem.

I don't know if the newer Canons will do the same thing in terms of adjusting the direction of feeding the paper but if you have or can get one of the older printers, I think you will have your problem solved with no modifications to the printer.

 

[The Hat]

Well said ghwellsjr, and I too have done the same with mine. The older canon printers that have a fixed side lay will print a sheet in the same position each time it is feed in to the rear tray. If I put an eyeball (magnifying glass) to the image it has good tight registration, quite enough to fool the human eye. Most inkjet printer achieves this when using the CD tray to print with up to five registration points on the tray. I have in the past re-run paper thought a large Litho press to achieve higher colour penetration and give a 3D effect. With direct screen to image systems now in most print companies the quality that is produced is brilliant, just look at your daily paper. Modern Commercial printers can use up to eight colours now for higher quality, but use only four for everyday publications..William35401 should take a look at screen printing where the method he describes is still used to day..

 

[ghwellsjr]

I don't know if the newer Canons will do the same thing in terms of adjusting the direction of feeding the paper but if you have or can get one of the older printers, I think you will have your problem solved with no modifications to the printer.

I tried the same experiments on my MX700 and it behaved in exactly the same way. This printer is one of the first Canon printers that had chips in the cartridges. I don't know about the current crop of Canon printers. Anyone else want to try it with a new printer?

 

[William35401]

thanks for al the feedback. i doubt i'll have much luck obtaining one of those MP760s locally but will look. i'd hoped such a registration issue would be a well-established mod by someone. actually 'the hat', i've been in screen printing business over 25 years and am bringing that experience to the table in this project. i have to print a photographic quality image on a unique substrate and then register it to another component quite accurately. that means the original inkjet print has to be printed in the same location on the page each time. i'm having limited success with the only weak link being the inkjet printers. i'm about to tear one apart to investigate how i might mod it myself but still hope for prior experience to emerge from someone on the list. thanks to all.

 

[ghwellsjr]

Actually, you would want to look for a used MP780 because they are much more popular. If you don't want an all-in-one, you could use the iP4000 which has the same printer engine.

I presume you're not going to run your "unique substrate" through the inkjet so how does it relate to an inkjet printer? Have you been working with an inkjet on this project already?

Where abouts are you located?

 

[William35401]

thanks for those tips george. i'm in alabama, across the great divide from you. and yes i am printing directly on the substrate with the inkjet printer. this is a cross-platform application of inkjet, screen printing, and perhaps offset, still in development. i have everything working except the critical registration of the inkjet printer.

since i last posted i've torn apart a couple of nonfunctional inkjets to compare the paper feeds, and see that the top loading printers (most) do have a much better mechanism. the cheap HP front load has a feed roller on one side of the paper only and thus would easily lead to misalignment. the lexmark top loader had two feed rollers spaced apart in the center of the paper with better side guides, and i can see that this would intuitively be more accurate. it also has a bottom rest that all the sheets align against prior to feed engagement. i'm next going to play with the wide-format HP that i have that allows horizontal pass-through of long sheets and banners. i might be able to mod this much like the artist in the link in my first post. i'd hoped for something a little faster than using register pins and single feeding paper, but it appears this may be necessary.

i'm sure this group is aware of the other forums with such specific inkjet agendas as 'direct printing on t-shirts' and the 'direct printing on printed circuit boards' folk? but all of their mods are focused on single pass printing (with a few exceptions for duplex).

still open for all suggestions. thanks.

 

[William35401]

huh, i was interested in the cannon ip4000 but see it is now discontinued and while cannon lists it as $59, those left at amazon are now $369! i wonder if the new cannon ip4700 is essentially the same drive train? i see it replaces the ip550.

 

[The Hat]

William35401..

The Canon ip4700 has a different rear tray than the older models and it probably wouldnt suit your purpose. Try and pick up an older Canon from somewhere, maybe (EBay) it would be your best bet. The ip4600 / ip4700 are the newer breed of printers that are built for speed/quality (Cost wow) and are nowhere near as user friendly. Its great to see that you breaking new ground with your ideas so have patience, it will come to you good luck William..

 

[ghwellsjr]

You could always go into a store and do the test I did. Just put one sheet of paper in the rear feeder and hold the right hand edge off to the left so that the leading edge on the left is going in first. If the printer sucks it up and prints the nozzle check not square with the page, then it won't be good for you. If instead it pulls the paper in a ways then retracts it and realigns it so the nozzle check prints square with the page, then it might work for you.

The other test is to simply put one page in the rear sheet feeder and do a nozzle check. Remove the paper and reinsert it and do a second nozzle check and see if the two printouts exactly overlap. Make sure the paper guide on the left is for the correct paper width.