Alignment issues

Post Reply
FlyingPete
Posts: 5
Joined: Fri Jul 21, 2017 11:29 pm

Alignment issues

Post by FlyingPete »

Hi all,
I am having some print and cut alignment issues, the cut seems to drift as it works up and across the page.

My print and cut work is typically printed on a 12x12" piece of sticker paper.

I have attached the corner images from a project (it s 9 images total - 3x3). The black area should be the same width right around the image. For example, the Top Left image, the cut has drifted Right and up by about 1-2mm.

I calibrate the laser each time and align the print and cut targets as precisely as I can. This effect seems to be consistent in all the jobs I do.

My Cutter is a SilverBullet, and I am printing on a Canon Pro10S. SCAL version is Pro 4.062. My laptop is a MacBook Pro running MacOS Sierra.
Attachments
Bottom Right
Bottom Right
BottomRight.jpg (176.62 KiB) Viewed 4346 times
Bottom Left
Bottom Left
BottomLeft.jpg (146.42 KiB) Viewed 4346 times
Top Right
Top Right
TopRight.jpg (168.73 KiB) Viewed 4346 times
FlyingPete
Posts: 5
Joined: Fri Jul 21, 2017 11:29 pm

Re: Alignment issues

Post by FlyingPete »

Another example printed some squares on 12x12" then replaced the blade with a blue pen, aligned it up and tried again, starts OK on the bottom left (by marker 3):
Attachments
Print and draw
Print and draw
Scan 3.jpeg (823.23 KiB) Viewed 4339 times
FlyingPete
Posts: 5
Joined: Fri Jul 21, 2017 11:29 pm

Re: Alignment issues

Post by FlyingPete »

OK, made progress, noticed two things:
- Accurate alignment is critical, the image MUST be square in the cutter, a millimetre or two out of skew is enough to cause problems even though the registration targets have been set accurately.
- I have noticed some drift in the media whilst cutting, the media was skewed by about 0.5mm from straight by the time the job was done, this is a machine issue and I am not sure how to address that.

Here is the latest test, much better than the first but not quite there yet:
Attachments
Print and cut test target
Print and cut test target
Scan 4.jpeg (725.87 KiB) Viewed 4334 times
SandyMcC
Posts: 1114
Joined: Mon May 09, 2011 7:01 am

Re: Alignment issues

Post by SandyMcC »

Basically, the drift you are seeing is the mat moving ever so slightly out of aligment during the cut. There are a number of reasons this can happen on a Silver Bullet:

(1) The cut speed is too high. I don't believe you mentioned what speed you are using but I would reduce it 100 or even down to 50 to see if that improves the situation.

(2) The blade exposure is more than is needed to cut that particular paper and, as a result, the blade tip is cutting into the mat a bit and is dragging the mat. It just takes a little bit to build up the drift over the course of the cut. So, if you can see any cut lines in your mat, try reducing the blade exposure. Hopefully you don't have a click style blade holder where your options are limited on setting the blade exposure.

(3) The bottom of the mat and/or the grit shafts below the mat are a bit sticky. You can clean both with isopropyl alcohol.

(4) The mat is touching the inside end cap which can also cause some drag. When inserting the mat for a PNC, make sure it's at least half inch from the right side.

(5) Always check the positions of the pinch wheels before every cut. They can slide a bit out of aligment when raising and lowering them frequently. Also, you want to use two pinch wheel positions that place the wheels near the two outer edges of the mat versus using any in the middle.

Hope this helps!
Sandy McCauley
Owner of http://www.iloveknk.com/
FlyingPete
Posts: 5
Joined: Fri Jul 21, 2017 11:29 pm

Re: Alignment issues

Post by FlyingPete »

Hi Sandy,
Great thanks for the tips! Will look into those...

Blade depth was almost cutting through the base layer of the adhesive sheets, so could be pulled back a bit.

Pressure was 100, speed 165.

I will make some adjustments and try again...
FlyingPete
Posts: 5
Joined: Fri Jul 21, 2017 11:29 pm

Re: Alignment issues

Post by FlyingPete »

Tried that, huge improvement! Almost bang on all the way! :D

Just about to try a full-width (24", I was using a 12" one) matt board too, that will allow all the pinch wheels to contact the board
SandyMcC
Posts: 1114
Joined: Mon May 09, 2011 7:01 am

Re: Alignment issues

Post by SandyMcC »

Very pleased to read this! :)
Sandy McCauley
Owner of http://www.iloveknk.com/
Post Reply