Head Height On Printing Coro?

[FLSignMan]

Hi guys,

After much research and debate, we recently decided to purchase a ColorSpan 5465. The unit was installed last month, and so far, the machine has been great.

One thing that we continue to fine tune is the head height for printing coro. Given the imperfect nature of a 4x8 sheet of coro, we have set the head height on our coro profile to 0.105. Occasionally we have a slight "shadowing" effect (overspray) on areas going from solid color to the white coro. We originally set our coro head height to 0.12 to take the possibility of a head strike as far out of the equation as possible. The shadowing effect was greatly reduced by lowering the head height, but I was curious to get feedback on what other 5400 owners have tried in regards to head height.

As always, thanks for your help!

 

[mrsticker]

head height

we too played with many heights...in the end to eliminate the possibility of a head strike 90% of the way into a 4x8 sheet we stay with .100 off with a 1 or 1.5 second delay in the print to help keep the material cool and not warp up...we vary between billboard mode and production speed

 

[anthony smith]

we have ours set to .115 with
shutters at 30% no delay have
the haze a little but not really a issue
We have wondered about ink use
we are not getting the prints that
we were represented as best i can figure
it is more than half again what we were
expecting

 

[WYLDGFI]

wow....you guys have your heads set quite high. Im printing on a Vutek Pressvu 200 at .070 or thereabouts. Why is it such an issue with the colorspans to keep the head heights so high?? We get no overspray....and rarely a strike.

 

[ksc]

Do not !purchase a hp / colorspan flatbed uv printer i have had mine for about 11 months with onley 60 hrs on it The printer has had over 60 in shop man hours on it (warranty repair time) and is not fixed yet....the printer was purchased 1/07 im having my lawyer return it for me....... 12 months of hell.....

 

[ksc]

ksc

as of 4/10/2008 98 uvx printer no replacement yettttttt!!!!!!!!

 

[tugwell]

We set our heads high also and use the delay to avoid warping the coro with the lamps. Works well.

 

[jazz60707]

you want to run at .120 with shutters at 20/20. with a 1.5 sec delay.
The overspray is "static". what I do is tape about 6 dryer sheets together horz. Then tape to back of printer and lower so they drag along the width of the board. This is a tip from the Colorspan rep himself. Also I use a static spray made by Sprayway called " 955 anti-stat static eliminator. For use on most substrates in flatbed printing.

 

[J Hill Designs]

so it eliminates anti-static? hehe

 

[WB]

We're running at 1.5mm headgap which is about .059" with the lamps on high. I put a fan at the back of the machine blowing over the Coro to help with warpping..

 

[johnnysigns]

Full Vacuum table here so we're running pretty tight tolerances over the media.