Flexi issue with plotter offset

[joelswork]

Hey guys,
This is driving me nuts. I have my artwork done and put a cut box around it with a .02 radius on the corners. Everything looks perfect and checks out but when I open in in production manager and then send it to the plotter (hp branded summa, then again to my big summa T series) the corners are jacked up. I checked the offset on both plotters and the offset is set correctly in there. I also went in and thought it may be just from making the box so I changed the box to outlines and tried again, same issue. The design is good but something between Production Manager and the plotters is messing with the offset. Any help or suggestions. These are small flags but it really is bugging me.

 

[Saturn]

How big is the piece?

Big rectangles (and circles) can be the worst at showing cut issues. Is this in all the corners, or is one corner particularly bad? I will occasionally get this on one corner when doing small radius corners as well. I usually imagine it having to do with material movement from the force of the blade itself, and things get the teensiest distorted.

I would get down at blade level and watch how flat the material stays on the surface of the cutter. If it comes off the surface or bulges at all while the blade is traveling around, that could be part of the cause. You can help with some of that by using more pinch rollers and/or more cut passes.

Another test you could do is to use that same cut shape, but lower your pressure so you're just doing a really light kiss cut, and see if it's still distorted.

 

[joelswork]

So I talked to a flexi agent for quite a while today and thought we had it, but we didn’t. Squares work, the plotter offset was perfect on tests, calibrated both media and OPOS, X&Y axis were spot on. Then we went into production manager and into plotter settings and thought we had it when we adjusted the knife offset in PM to match what’s on the cutter and clicked the box. It cut the rectangle and it looked right but upon later inspection it was really over cutting the offset. Larger radiuses were fine (or just too big to notice but that tight .02” radius just isn’t working). Speed and pinch rollers were looked at beriefly but since it was consistently bad on both machines over the entire 30 or 54” they were ruled out… stuck!

 

[Saturn]

I never go below 0.05", and often will make 2x2 and 3x3 stickers with corners at 0.1 to 0.15.

Now that it clicks how small you were trying to go, I don't think there's any good way around it. At some point it goes from jigsaw to bandsaw and the little blade just can't make those turns.

 

[joelswork]

The tangential cutter did do much better but still noticeable… I’ll give it a go at at a bit bigger radius to see if that helps. Thanks for the input!

 

[Vassago]

You've always got to remember the blade needs time to turn. The old gerber tangentials could just about do it as they rotated the blade to match the angle being cut and were slow, but small angles will always be a problem.also got to make sure the point of the blade is still there - that's an easy thing to miss