Vinyl cutting leaves 'barbs' on rounded or knockout letters

[ngoepp]

I'm cutting text no smaller than 3/4" letters on 3M HP vinyl with a Gerber EnVision ripped from Flexi and I keep getting 'barbs' (partial, jagged, etc.) on the O's, A's, S's, B's, P's, etc. The O's look the worst. I guess the start and end cuts are going off track? Not quite sure.

I've already changed the blade from an old 30 deg. to a brand new 45 deg. with only slight improvement. I've also tested and recalibrated the X and Y axis', messed with the depth, slowed it down, changed orientation, corner settings, etc. etc. We've even sent it out to our Gerber Rep for servicing which only fixed the problem temporarily.

This vinyl is going on clear acrylic donor plaques, second surface and are up for serious scrutiny. They've got look perfect. I've never had this much trouble with a Gerber machine before. I'm at a loss here. Any ideas?

Thanks!

 

[BrianKE]

Don't know about Gerber (I have a Graphtec) but I get the same results with an improper offset setting.

I had to go through about a dozen test cuts, changing the offset value 1 step at a time, to get just the right offset and no unfinished cuts.

I have also heard that some machines have an overcut feature that will cut beyond the original start point to help with small letters and incomplete cuts.

 

[trik]

does it do it on any font? Or just the specific one you are trying?

 

[ngoepp]

It's really hit or miss. It's generally worse with serifed fonts although I've seen it happen with sans-serif. And of course, it gets worse the smaller the font size.

I'll double check the offset. Flexi Production Manager has a box to check and set for the Overcut/Offset function but I don't have those checked. Otherwise, there is a "Corners" function that I can tweak a little but I haven't had much luck with that in the past.

Thanks for your help, I'll keep at it.

 

[trik]

Like Brian I have a Graphtec, really have had to adjust anything on it, but I had an old ioline that I had to tweak the offset, to make it work.

Good luck, sorry I couldn't offer more!

 

[jiarby]

I bet $1 on blade sticking.... oil/grease the blade holder spring/piston.

 

[ngoepp]

Well, so far I've tweaked the Corners function up to .022" and slowed the Accel down to 2g. I really hate messing with the Corners function because sometimes it rounds off fonts with sharp edges. Meh, maybe this will work. Yet still, I'm open to suggestions.

 

[Ponto]

Too much wear on the cutting strip may have an effect on the quality of cuts ... I've had to replace mine since I noticed poor results as well.

JP

 

[ngoepp]

Ahh the cutting strip. Gonna change that out in the morning. Oiled the blade assembly. Will see how it goes in the morning.

 

[ngoepp]

It's back at it.

I thought I knew how to calibrate plotters before I started using this particular Gerber EnVision. It's reverted back to cutting horribly and leaving the barbs/offset cuts. Not even the service guy fixed the issue. Any new ideas?