Brand New Blade "Tearing" Vinyl?

[bnosanchuk]

We recently started cutting 2mil cast vinyl for one color designs, instead of wasting ink printing. Last week, we had to change the 60 degree blade as it had become severely dull (we thought the blade would last longer than 2 months, but we have been cutting 6mil vinyl a lot so perhaps that dulled it faster?). After changing it for a brand new 60 degree blade, we noticed the vinyl wasn't cutting cleanly. It looks like the blade is making tiny tears or ripping, like it's dragging across the surface, instead of cutting it. We've adjusted the offset to manufacture suggestion (.5 for a 60 degree blade) and even tried increasing the pressure from 50 to 65 and even 80. Still getting the little rips. The blade cuts thicker material fine without the tears. Is this maybe a faulty blade? The first blade and the second blade are both from Clean Cut Blades, and the first one worked perfectly with the 2mil vinyl. The blade is also properly positioned, extending out about the width of a credit card. Anyone have any ideas?

Printer: Roland Sp-540V

 

[rjssigns]

We have the exact same machine and here is what I know about your problem. Remove the blade and check the cutting edge with a loupe or magnifying glass. Bet it is missing an edge somewhere.

I had two blades in a row that the tips fell off in the middle of a job. Having to do a job three times is a great way to make money, NOT!

From my extensive experience in industrial settings I've learned one important thing: Just because its a brand new part fresh out of the wrapper doesn't mean it's not defective. You can take that to the bank.

 

[Tony McD]

It is also possible your blade holder is dirty or worn out. The blade should freely spin in the holder, and not have any side play.
Since 1994, I have had to replace one blade holder in a well used machine.
Also check the cutting strip under the blade. If it gets a groove in it (usually from too much pressure) it can cause the blade to hop and skip.

 

[bnosanchuk]

Testing

Thanks so much for the advice! I will double check these things tomorrow and let you know what I find!

 

[bnosanchuk]

Update: Faulty Blade or Something Else

The cut strip looks great, no scratches or tears. I also check the blade holder and the blade spin freely, so don't think the issue is there. So I checked the blade and yes, it does look like the tip is chipped off. Is this because of a faulty blade or could anything else be causing this, like a very thick material etc?

 

[Jillbeans]

I always used a 60° blade just for cutting reflective, and a 45° or I think even a 30° blade sometimes for cutting high-performance vinyl. This was on my IV-E (Gerber) I have no idea what is in my Graphtec but I have only bought 1 new blade in 3 years. I have a separate blade for reflective for that.
Love....Jill

 

[Cynosure]

Better late then never...but i agree, you should be using a 45° blade for regular vinyl and save the 60° for reflective. I was told by my vendor the blade comes down too far and snaps, ever so minutely with the thinner vinyl.

 

[James Burke]

I've always had better success using a 30 degree with vinyl in our Gerber GS15.


JB

 

[Jester1167]

Depending on the machine and how you load the blade, you can chip the tip during the loading process. On a Graphtec you have to make sure the new blade and spring are centered you will chip the tip screwing in the retainer and setting the depth.

 

[handbrake]

I've had this problem before, on my SP300. All it was was the blade holder not spinning freely. After some time the ball bearings just go out of wack. You can turn the blade by hand and it seems ok but in the machine it'll just tear.
It's the blade holder for sure. Fixed the problem for me every time.

Cheers

Dan

 

[Grizzly]

Chiming In

We recently started cutting 2mil cast vinyl for one color designs, instead of wasting ink printing. Last week, we had to change the 60 degree blade as it had become severely dull (we thought the blade would last longer than 2 months, but we have been cutting 6mil vinyl a lot so perhaps that dulled it faster?). After changing it for a brand new 60 degree blade, we noticed the vinyl wasn't cutting cleanly. It looks like the blade is making tiny tears or ripping, like it's dragging across the surface, instead of cutting it. We've adjusted the offset to manufacture suggestion (.5 for a 60 degree blade) and even tried increasing the pressure from 50 to 65 and even 80. Still getting the little rips. The blade cuts thicker material fine without the tears. Is this maybe a faulty blade? The first blade and the second blade are both from Clean Cut Blades, and the first one worked perfectly with the 2mil vinyl. The blade is also properly positioned, extending out about the width of a credit card. Anyone have any ideas?

Printer: Roland Sp-540V

Hopefully you've already figured this out but thought I'd share my experience.
My Graphtec did this on 2 brand new blades (from Havels), braking the tips within minutes of cutting. For me it was the blade holder. If you look down the holder, removing the blade, you'll see a 6 point star with round inside points, essentially the little bearings where the blade rests and twists. The farther those outside points go out, the worse shape your holder is in. When I got the new holder, you could completely tell the difference.

 

[Dakotagrafx]

The cut strip looks great, no scratches or tears. I also check the blade holder and the blade spin freely, so don't think the issue is there. So I checked the blade and yes, it does look like the tip is chipped off. Is this because of a faulty blade or could anything else be causing this, like a very thick material etc?

you said you was using a credit card depth - you broke the tip when you cut thru the vinyl - that is easily 40 times too much blade - if you take the holder out and manually cut the vinyl you should be just cutting thru the vinyl and leaving a mark on the backing - then put the blade back in and adjust pressure as needed. with setting using a credit card you can cut thru the vinyl, backing and the cut strip on a graphtec ( cheaper cutters use thick plastic so probably not thru them) with that much blade you are cutting thru into the cut strip and snapping the tio of the blade off when it turns.