Static problem with plotter

[foreword]

Hi all,

I have a static problem, hope someone here can help.

I have a vinyl cutter (re: plotter) to do sign work, vinyl lettering.

When we purchased it (1 1/2 yrs ago) we've had problems from the get go with the machine cutting erratically. At the time, tech support told me it was either a lack of computer processing power and RAM memory or a static problem. At first I thought the machine was defective and thought tech support was giving me the run around to avoid dealing with warranty. So I gave up on the machine and it sat there for more than 8 months.

Recently, after purchasing a new PC, I decided to retry my plotter. New material (vinyl) was purchased to do a job. The whole thing was running perfect and I really believed the PC theory and tech support was right. For three days we cut and had no problems, until we got to the end of the roll and the remaining vinyl fell off the roller and onto the floor (carpet). As soon as that happened the plotter started it's erratic routine.

So now I know static is my problem.

For this job, it really wasn't a problem avoiding static since the cuts we did were never long enough to reach the floor (less than 40" at a time), but sometimes I need to cut from pieces which are longer than that and contact with the floor is unavoidable.

My question is:

How can I insulate to avoid static buildup,

and maybe, do I need to do something to somewhat dischage my plotter and PC since I suspect maybe they could be overcharged in one direction or another ( I don't know here, but the fact that my machine was sitting for a while could've with time just balanced itself out).

Thanks for reading and even more if you have a solution for me.

 

[MikeHalloran]

You could:

- Fit static control brushes to the plotter where the film drapes over an edge.

- Move it to a non air- conditioned space.

- Put a humidifier in the room with it.

- Take the carpet out of the room.

- Install a static control mat under the plotter where the film hits the floor.



Mike Halloran
Pembroke Pines, FL, USA

 

[logbook]

>How can I insulate to avoid static buildup ...
You do not insulate to avoid static build up, you do the opposite.

You can get spray for carpets that makes them slightly conductive to reduce static buid-up. Cleaning companies often do this as a sideline.

Old style plotters/printers used to have Christmas tinsel brushing against the sheet feed paper in order to give a discharge path. The tinsel was wrapped around a bare earthed/grounded wire.

 

[logbook]

It would be a good idea to make sure the vinyl roll is earthed/grounded. As the vinyl is unwrapped it will create a static charge and this needs to be dissipated. Tinsel or specialist static control brushes should lightly touch the outer surface of the roll, ideally on the freshly exposed inner surface before it enters the plotter.

Having an (air) ioniser in the room may be cheaper than using a humidifier.

 

[itsmoked]

Realize the charge you are dealing with comes from the triboelectric effect. This is the generation of static charge via mechanical means. Certain materials moving against other certain materials exacerbate the buildup. The developed charge is physical and surface related. Imagine that it is a thick coating of dust on the plastic surfaces. Removing this charge can also be a mechanical process. Hence the tensile that the plastic rubs across that will cause charge to be scraped off and directed somewhere(ground).

Separating non-conductive material develops charge. Pulling 5 inches of Scotch tape off a roll generates thousands of volts, the same with your plastic.

The plastic rubbing across your carpet is providing the movement of two different certain materials across each other. A change in the floor material would eliminate one source of charge. You could try a piece of sheetmetal under the system. It comes up to 4x10ft sheets at sheetmetal shops and can be sheared by them to whatever size you need.

The roll unwrapping is also adding to the charge. A tensile discharge would remove the un-rolling charge.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[Compositepro]

Static accumulates on non-conductive surfaces because it can't find a conductive path to ground. Check out Ion Cord

http://www.fibraplex.com/IonCord.htm

It does not have to touch the film in order to dissipate the static and does not require any power supply.

 

[ssn596]

Not to get kinky here but what you need is bonding.

As everyone has said the problem you have is you are working with insulators. These ie plastics are very prone to build static charges and BIG ones. In some cases I have seen these WOULD hurt.

You need to somehow connect EVERYTHING including operator to a common point and GROUND it. Now all are at the same potential and any static charge will bleed off to ground.

GET rid of all insulating type material ie the carpet - put in a sheet of steel. Use that ION cord on the plastic on teh infeed and on outfeed. Bond the cutter and computer etc etc etc.

Dan Bentler