The case of the shrinking tape

[Jen Goodwin]

I print decals for a company who uses them on products that they sell for measuring water levels. Essentially, they are millimeter rulers. I have set this up in Flexi AND Omega, both, using the rulers set to millimeters and they are right on on the screen, dead on to the measurements set up in both programs.
When I print this out to the Edge, they end up approx. 4 mm off? WHY!?!?!?! Arrgh! I'm surprised that it would be that much off, do you think it's caused by the heat of the printhead?
I kept thinking he was stretching them putting them on...not the case, right out of the edge, without being removed from the backing sheet, it's off.

 

[Marlene]

4mm is a lot to be off! Have you tried printing other things and checking the size like a 1" x 1" box? If it's off that much, I'd ask one of the Tony's at GSP what's up.

 

[Baz]

Its definately the heat reacting with the vinyl. Try different kinds of vinyl. They dont all react the same way. I'd still be worried of the increments being off also when applying the vinyl onto the substrate.

 

[Jen Goodwin]

Thanks you guys! I print stuff all the time, I have never noticed anything else being off; mags, decals etc. I am printing some decals today and I am going to print a box as long as the tape and see if it measures up.
I am thinking it has to be something wrong between the rulers in the computer and the output, rather than heat. Edge positive gives me the same results as the Oracal 651...
I set this up by using a line segment, repeating it using the repeat tool making them 2mm apart, then I added a stroke to the line segment. According to the rulers and measurements in both programs it's right. According to the output and a millimeter tape measure, it's wrong. The guy told us it was off by 4mm, I am finding it's more like 2.5 mm. I'm baffled!

 

[Baz]

As a test ... increase your the size of your object by 2.5mm .. see what your output gives you. It wouldnt be the perfect solution. But short term it might get you out of this problem.

 

[Fred Weiss]

I had the same problem with the measuring tapes I made for my Keencut table.

I created them using repeats and when I checked them, I found errors of .005" to .02" running the length with no particular rhyme or reason. So I repositioned them all and ran the tapes on my Edge. Then i checked measured them and found that they were between .375" and .5" longer than they were supposed to be over their 31" length.

I then moved all the ticks an even increment figured out by the number of ticks divided into the total print error and reprinted it. It was then close enough to call accurate.

I asked about it and was told it had to do with how the software sees things in pixels and has to translate that to inches or millimeters etc.

These are the tapes mounted on the cutter table. the one in front is factory installed. All the ones on the white table top are what I made.

 

[Jen Goodwin]

Well, I believe the mystery is solved with the help of a Gerber Mastermind...(Thanks Tony T!)
Sprocket Holes! The measurement from the center to center of the 3 sprocket hole punch is suppose to be 5", but in actuality, mine varies. Over a 10" span the measurement can be off by .104" (2.6416 mm)
I am printing on Oracal (and we all know they have had their issues with the hole patterns) and I'm pretty sure Gerber would try and hold a tighter tolerance than that.
I am going to attempt to play around with this to get it sized fairly accurate but with the hole pattern being the issue, it's always going to vary from roll to roll. I wonder...are there certain brands that hold a tighter tolerance with the hole punch than others and would the clear mylar backing sheet help with hole tolerance also? Maybe I need to use Gerber vinyl with the clear mylar backing sheet to get the best results? Does anyone know what the number is for that stuff? Isn't it just the regular number with an 'i' added to it or something like that?

 

[Fred Weiss]

It's the 225 vinyl series.

 

[Jen Goodwin]

Thanks

 

[Marlene]

The Tonys are good and can figure out just about anything, glad they were there once again.