When to replace UV bulbs

[Cmartorelli]

I have a HP Scitex FB 6100. It is about 2 years old but get very little use. Most days it will only print for about 1 hour. (we do very high end custom displays) I don't have any issues on the flatbed but in roll to roll mode the print quality is not very good. I have tried adjusting tension, vacuum etc, but just can't come close to the quality of printing on the table. I asked HP and the said the material is not "approved by HP'" which is no help. I was think maybe it time to replace the UV bulbs, but them again its fine when I print on the table.
So my question is how do you know when to replace the UV bulbs ?

 

[miker]

typically when the bulbs cannot cure the ink well enough to have it adhere to the substrate, so I doubt that is your problem.

 

[Gino]

Welcome from PA............................

 

[omgsideburns]

It's probably a feed calibration issue.. or some other gremlin. I know some materials stick to the platen so I have to adjust the platen vacuum, or adjust the grit roller tension. (not using the same machine but definitely know the difference between uv lamps and media feed).

And no, don't wait until the ink isn't curing to replace the lamps. Usually I get more overspray and weird banding issues that you can't seem to solve when the lamps start to die because of uneven drying.. that and they won't fire every time you turn them on.

 

[Gino]

Your machine has a counter on it.... somewhere. Most lamps are good for 250 to 400 hours. Once you get around 350 hours, I'd start thinking about changing them out. If you wait too long, things aren't being cured properly and you'll experience many returns.... or complaints.