new graphtec- most likely user error. but I need some help

[Geneva Olson]

I got my new plotter last week. I made a small print run and plotted out some cool graphics. I said, woohoo, I'm set. I had a big run with a little trouble. Flexi support helped me with that one and it was all good.
Then on Friday, I plotted a crap ton of reflective. Blade was chewed up and worthless. It was the only blade I had since it was a new machine. Got some new ones in and started plotting. They aren't cutting properly. SOME items weeded like butter, other parts weren't even cut at all. like it barely cut. SO, I increased the downforce. But the numbering system looks different (?). So I cut the next batch and it weeded like butter. It did. however cut through the paper in an area. WHAT am I doing wrong?
The plotter is a graphtec 9000-140. any advice would be greatly appreciated.

 

[Jason Thomas]

Are you using 60º blades? Did maybe the cutting strip get ruined?

 

[Solventinkjet]

Yeah a 60º blade and make sure to change the offset setting to the proper number. Different angle blades require different offsets. The offset for your blade should be on the package it comes in or you can usually look it up.

 

[Geneva Olson]

Are you using 60º blades? Did maybe the cutting strip get ruined?

I believe the blade that came with the plotter was 45 degree. I now have a 60 degree blade in it. The cutting strip is not ruined. It is smooth and clean

 

[Geneva Olson]

Yeah a 60º blade and make sure to change the offset setting to the proper number. Different angle blades require different offsets. The offset for your blade should be on the package it comes in or you can usually look it up.

I set the offset when I did a test cut. That seems fine as well.

 

[victor bogdanov]

How far is the blade sticking out? probably have to play around with blade depth

 

[BigNate]

Sometimes going back to the working theory of the device may help.

1)the cut depth should be determined by how far the blade protrudes below the flat circle opening at the bottom of the holder.

for this to happen:

2)the down motion of the head must be enough to allow for the head to 'float' against the downforce determined in the programming.
3)the downforce in the settings must be more that any dynamic up-forces that may be caused during cutting - otherwise an up-force can overcome the set downforce and the blade holder lifts up a little.

after this is done, then:

4)set the offset correctly to handle corners.

I see a lot of people not realizing the relationship created in 1-3. If you see good cuts on the slower areas (lots of details where the plotter runs slower) but some long straight cuts that are not cut through, this usually means you need more downforce as the blade is getting too much lift from the angle and the speed. (If you have problems weeding the details that were cut slow, but the straights are cut clean, check the offset.)

sometimes it can help to just slow the entire plotter down really slow - so it does not even slow for corners. Doing this eliminates an entire area of variables. After you have clean cuts everywhere, slowly increase the speed and watch for lifting on the long straights - making adjustments to downforce as necessary.

 

[BigNate]

(changing from a 45 to a 60 or back can change the needed downforce - but sometimes the more efficient cut is the determining factor, sometimes the angle of attack of the 'wing'(cutting edge) is, - basically I have not found a good rule-of-thumb other that changing blades may require a change in downforce as some media will need more downforce and others less given the same change.)

either way, when you change the blade angle you have changed a variable that can change your cut unless you adjust other settings to compensate.