large mural prints not tiling accurately

[depps74]

I have an HP latex 315. A while ago I made a print of about 10 tiles 50" x 10 feet on each tile. On the last tile it did not line up vertically The last tile was about 2" off in height. I was able to work around it as it was a line graphic (not a photograph) and have found by reading threads on signs 101 that this can happen if the take-up reel is not pulling correctly or drifting as it is pulling. (spooling to one side) I am wondering if there is a way to test out before I print another large job this theory. Or perhaps if there is another way to diagnose what is actually going on. My take up reel is a 3rd party one, but I have printed so many murals without this issue ever happening.

 

[F1225hgB42w]

We had a 360 and had major issues with drift, we ended up selling the HP and buying another Epson S80 since we never had issues with them.

On the Epson printers we can do a media feed calibration, I assume the HP will have something similar, but if not almost any RIP will also have a media feed adjustment setting you can use to correct feed issues.

Our issue with our HP was that almost each panel ended up feeding slightly different, so almost all seams had to be stretched or squished to make things line up. In the end we gave up HP.

In all fairness, we have 10 Epson printers currently and have probably owned 20+ in the last 5-10 years additionally. So we are a little biased, we like Epsons.

 

[Jayefkay531]

If the take up reel is causing the material to not feed out enough, you'd see the print essentially printing a bit on itself. Is the print still crystal clear? I've only owned hps and the most skew I've ever gotten on the take up reel was maybe 1/2" so I can't relate too much, but I'd suggest taking a look at media feed calibration and length calibrations if the 315 has it.

 

[jimmmi]

If you haven't already, create a profile optimized for tiling with 10-12 pass. Enable take-up reel from the beginning so the omas will be calibrated with the take up reel. Also the counterweights make big difference.I always use them Also find the ideal temperature. Dont use the canned profiles that usually have the highest temperature. Profile optimized for tiling preheats the printer and adds 1000ms interpass delay. So you can lower the temperature enough
.I do these steps and never had size problems. Of course for tiling i use only polymeric with coated liner.

 

[mbasch]

The 360 puts too much weight on the take up reel. You'll need to counter balance it to take some of the weight off.

 

[myront]

Also heard it's a good idea to rotate every other tile 180deg

 

[Steenland]

I agree with jimmmi and mbasch: without the counterweights, there's too much pull on the take-up reel. We have a 365 and keep the counterweights on all the time.

 

[jimmmi]

I also made some extra weights and added to mine. For having even less tension.

 

[Ahmed Samy Nagada]

That is a common problem with Latex and Z serious, happens because of the OMAS module. Sorry to say that but the only solution is to stop the optical media advance sensor OMAS. If you are using RIP like Caldera, there is an option to disable OMAS, in this case you will get consistent results but still you will have to flip each alternate tile 180 degrees.

 

[MelloImagingTechnologies]

Typical HP unless your printer is over $100k

 

[depps74]

If you haven't already, create a profile optimized for tiling with 10-12 pass. Enable take-up reel from the beginning so the omas will be calibrated with the take up reel. Also the counterweights make big difference.I always use them Also find the ideal temperature. Dont use the canned profiles that usually have the highest temperature. Profile optimized for tiling preheats the printer and adds 1000ms interpass delay. So you can lower the temperature enough
.I do these steps and never had size problems. Of course for tiling i use only polymeric with coated liner.

what is polymeric material is that a brand?

 

[jimmmi]

what is polymeric material is that a brand?

Its type, quality. There are monomeric (cheap 2-3 years), polymeric (intermediate 5 years) and cast( best and expensive 7+ years)