Print + Cut - Can't get cutter to contour cut accurately

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Rjbrittain11
Posts: 1
Joined: Wed Oct 16, 2019 7:42 am

Print + Cut - Can't get cutter to contour cut accurately

Post by Rjbrittain11 »

Hi All,

First time post.

Stats:
MacBook Pro 2016
SCAL 5 - Version 5.022
Cutter: Titan 3
Printer: HP TM-305


I have a Titan 3 Cutter and no matter how accurate i get my laser calibrated, it never seems to cut exactly lined up. Right now my laser is calibrated at:

X: -22.725mm
Y: 4.575mm

I always make sure my X & Y on the cutter is at 0,0 as well.

Here is the pen lining up exactly with the crosshairs when doing the laser calibration test with the crosshair image:

Image

And here you can see from the images below how off it is:

Image

Image

Image

My Shadow Layer is set to 0.100 and these images are 6" in width. The Shadow Layer is perfectly aligned i the SCAL file.

Anyone have any tips/tricks to get this darn cutter to be accurate? Heck, sometimes it changes slightly when doing the same print without changing a thing other than the vinyl on the cutter. I dont change the head position or the laser calibration setting. I just take the cut images out, replace the sheet with a new one and alight the registration marks to the laser as instructed, and when it prints its not the alignment of cut.

At this point I am thinking that maybe the Registration Marks are too thick so when its detecting its slightly off? If that might be the case, can i change the thickness of the Registration Marks?

Any help at this point would be greatly appreciated.

Robert

SandyMcC
Posts: 847
Joined: Mon May 09, 2011 7:01 am

Re: Print + Cut - Can't get cutter to contour cut accurately

Post by SandyMcC »

First off, any time I'm calibrating a cutter for contour cutting I follow up with a simple test of four arrows on a sheet like this:
Capture.PNG
Capture.PNG (19.99 KiB) Viewed 887 times
Why do I use arrows? (1) Because if I used rectangles I might put the printout into the cutter the wrong way. lol (2) Arrows have both horizontal and vertical lines I can reference when adjusting X and Y values.

Why do I have 4 arrows? Because the first one cut is the one you want to use for adjusting your calibration numbers. The other three should match the first but if they don't, then you know it's tied to something else and nothing to do with the calibration.

Before I get into reasons why the other three arrows might be inaccurate, have you first done a sizing calibration for your cutting? Cutters do not necessarily cut exact dimensions. So you need to cut, say, a 10" x 10" square, measure it and then adjust the X and Y in the following window and recut until your square is perfect. These values go under Cutter>Cutter Settings.

To calculate the resolution: current value (usually 1 for starters) x size of shape in SCAL / measured size of shape
Capture2.PNG
Capture2.PNG (4.03 KiB) Viewed 887 times
Until your Resolution is calibrated, you'll never get those 4 arrows cutting accurately. Also, if you do need to adjust your Resolution, then you'll need redo your laser calibration which uses those numbers.

So, other reasons...

How large is your project? In general, the more the cutter has to move a material in and out during a contour cut application, the more likely the cut will eventually be off... which is called "drift" and is due to friction. This is why you see cutters with intermediate reg mark capability so that more reg marks can be scanned during the cut and corrections made. One way to see if you have drift is to cut a full page of small circles and see if the error gets worse as the cut progresses.

Some other possible reasons include:

Too fast of a cut speed. Try a slower speed to see if the accuracy improves.

The pinch wheels are no longer centered over grit shafts beneath. Even if one of the wheels is half on / half off a grit shaft, it can cause slight skewing.

Make sure the blade isn’t over-extended which can cause it to cut too deeply. Since you're cutting stickers, I wouldn't expect this to be the cause since the blade isn't fully penetrating the material.

Make sure the pinch wheels and grit shafts are very clean and not sticky at all. Clean with a lint-free cloth and a small amount of isopropyl alcohol or Un-Du applied to the cloth.

Good luck!
Sandy McCauley
Owner of http://www.iloveknk.com/

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