Drops of ink on banner

[Gary Birch]

Hi Martin
It may be obvious but have you tried doing your weekly clean before you start printing??

Cheers

Gary

[Martin Oxenham]

Yes we are very fussy with cleaning but this only seems to happen on banners.

[Chris Wool]

martin double check your wipers are in good nick.
head clearance and static are possibilities

chris

[Kevin Flowers]

Martin
What RIP are you using & what make media, some profiles that lay down a lot of ink fast can cause the problem, have you tried a different profile? different Head speed/ quality setting. If you can print same type of image on vinyl then the problem points to the variable which is the profile. Also banner can fray sometimes interfering with the nozzles may be worth a check.

Kev

[Jason Xuereb]

try pre spooling the media and seeing if it fixes the problem. Sometimes the force required to pull the media from the roll creates a slight shudder and I’ve had drops of ink on the print.

Pre spooling I don’t tend to get these drops.

[Glenn Sharp]

not sure with the SP540 but has it got head height adjustment…..it’s not set too low & catching is it ??

[Jason Xuereb]

glenn: it does but in the normal setting its set at the lower position im pretty sure and you can set it higher if you use the longer clamps.

[Shane Drew]

In your printing profile for the banner material, are you increasing the ink use/qty?

I’d guess you may have an issue with your pumps not removing the waste properly, so when your heads don’t get cleaned properly and drop ink in the process. The fact that it happens at the end of the print is a good indication that the waste is building up and not being removed properly.

If your other material is OK, your profiles may use less ink, which will contribute to the less likelihood of a buildup as quickly.

[HEYSKULL]

I would also guess the pumps!!!
But here is a thing I have noticed on a friends Mimaki when printing banners it looks as if the static of the banner pulls more ink through.
I am just wondering if it is maybe a mixture of the both.
Is it just at the end of a banner no matter how long it is?
Or does it just happen on really long ones..
Make the banner that little bit longer!!!!! So you have an area were it can drip off on!!

SC

[Ian Bingham]

Some times its head speed, because of the quantity of ink used , you may have to turn the head speed down a bit

[Radu T]

I sure hope You are printing with the media clamps on, as depending on the banner type, the lints on the margin fine scratch the heads resulting in the formation of small ink drops.
A broken damper (that takes false air) could also be a cause, but normally ink spraying and ink drop-outs are the phenomena for this one.

Also please note that the SP540 has some grounding problems, so electrostatic charge forms quite easy.