White dots on the image (ROLAND RF-640)

[harperwenson]

The image produced by our Roland RF 640 printer has white dots, sometimes there are a lot of white dots at the start of the printing process. We have checked that the white dots are not coming from the file we are printing or dust, but from something else, but we are not sure. Can anyone tell us the reason?

 

[damonCA21]

It is normally contamination on the vinyl. This stops the ink sticking to it properly and it pools around the contaminated area causing a spot with no ink.
It could be a bad roll, or something in your shop is getting on there. You can try wiping down the vinyl first with IPA before printing and see if that fixes it

 

[harperwenson]

Ok

It is normally contamination on the vinyl. This stops the ink sticking to it properly and it pools around the contaminated area causing a spot with no ink.
It could be a bad roll, or something in your shop is getting on there. You can try wiping down the vinyl first with IPA before printing and see if that fixes it

Ok, thanks for the information

And the image above shown is white spots on a sticker. I've tried to print it on other print media such as albatros and satin (not sure what is the english name of it), it shows no white spots. Probably it's the sticker itself or the settings of the machine. The technician who handle our machine make a new settings once but i'm not really sure.

 

[Mike Paul]

Almost always bad material.
Pull off a few feet and try printing again.
If it still happens have it replaced.
Happens like once a year at my shop,
Bad roll of vinyl and fisheyes with ink.

 

[Broome Signs]

the roll is contaminated with particles and grease from your sign shop and staff
when loading media all ways pull at least 3ft of the roll.
yes, wasteful but necessary

best practice, give clients longer lead times and block all your weeks printing up in one go
work smarter

PB

 

[MikePro]

those dots are called fish-eyes, for reasons stated above.
plasticizers have migrated within the material, contaminating the surface

in a pinch, to "make it work", I've scrubbed the material with isopropyl & lintfree cloth but there's no guarantee
otherwise just get a new roll of material and save yourself some headaches.

 

[guillermo]

and it happens only with red color, many times I had this problem, solution....... get another roll.
If the roll is at least 90 new, you can probably exchange it, take it back to the seller and do not cut the material printed, so they can see.