Roland SG300 vinyl not tracking accurate

[m2w]

Hello, I have problems cutting printed laminated jobs especially stripes or any other designs where the vinyl to be cut needs to track through the machine numerous times. Before I remove my print from my machine, with a pen I make registration marks on the edge of my vinyl so that I can line up the vinyl back into my cutter in the exact position that it left the machine. I have noticed when the vinyl goes back and forth numerous times that my registration marks don't line up to the exact position meaning the vinyl is skewing in the machine so I'm always going to be having a cutting problem. I thought I had that problem fixed about a year ago after exhaustive research and many different components being changed on my machine we found out that the pinch roller plastic case was cracked so I was getting uneven down pressure on the pinch rollers which caused by vinyl skewing but since I got those replaced it has helped but it's still not perfect. Has anyone else ever had any issues similar to this??

It is very frustrating...

 

[woolly]

a few things you may have not done
poor media backing does not stay flat if its buckling it will miss track
too much heat does the same
eg. 2 mts of laminated vinyl weighs quite a lot, the speeds must be lower its really the change of direction that causes the slippage so the up speed must also be reduced
use as many pinch rollers that you can get in i use 2 to print 3 or 4 even 5 on the vs to cut.
blunt knife, poor holder, to much pressure contribute to the problem. a bit of cleaning and polish on the bed and cutting strip helps the vinyl to move over the cutting strip while under the pressure of the cutting knife.
as a test because you leave your own marks for reference you could run the cut job with no knife and see if the problem persists.

 

[netsol]

i am always of the opinion that a new set of pinch rollers ( oem NOT aftermarket) is the first, most important step.

even pressure is a must & oem pinch rollers have much tighter quality control
the geometry of the outside pinch rollers keep the substrate taut and minimze head strikes. i keep a full set of aftermarket pinch rollers for emergency situations but only. to keep running while waiting for the real thing to arrive

 

[m2w]

Thanks for the comments, I have a few things to try

 

[Axs]

Before you swap any parts I would confirm that your machine is level, and that the bars that your media holders sit on are square on the machine. Also, slowing down the up-speed can help if you are experiencing slippage.

Also take a look at the left and right pinch roller assemblies, on two machines I have found stress fractures in the black plastic which were the root cause for media not tracking straight.

If none of those work, then definitely replace the pinch rollers next. There's a newer style of middle rollers that are softer (they are clear on the sides) which help with this. Like netsol mentioned, make sure you are using the conical rollers on the left and right side.

 

[m2w]

I have the vinyl tracking much better, it would be nice if the machine had some guidelines or indicator marks so you knew the material is feed in squared off. I did have hairline cracks in the roller black plastic assembly which caused me grief for months. My service tech replaced them months ago and I just realized that the roller were installed backwards. The roller taper was to in inside...I flipped them around so the taper was to the outside.

 

[rjssigns]

There are printers that skew the media while printing. To the naked eye everything looks fine until you start taking measurements.

OP needs to make sure the lead end of media is perfectly perpendicular to the edge of the media. Then it has to be loaded perfectly square. A lot of tracking issues disappear by making sure of those two things.

Last thing to do is take out the manual and read the tracking specifications/limitations.