[jupitermoon]

I have had my vinyl cutter for a little under a year now. It is a MH721 cutter.

Recently it's been messing up big time and I am at a loss as to how to correct it.

Certain designs it prints great, but with others it will print fine then get to a certain spot and go completely out of alignment, the lines don't connect which ruins the whole design. I end up having to take it out and try and correct the mishaps with scissors which takes forever.

I have been feeding the vinyl properly, no problem with the blade and the rollers and working fine too.

If anyone has any technical ideas or advice I would really appreciate it as I am really behind on orders

 

[splathead]

Make sure your design isn't the culprit. Look at it in wireframe to make sure the lines look like they should.

 

[BrianHahn]

Please check your cutting strip and make sure that there are no gouges in it. If there are, use a spoon to smooth out the cutting strip and then tape over it with scotch tape until you can have it replaced.

 

[jupitermoon]

Thanks guys, the design 100% is not the culprit as it used to cut perfectly fine.

 

[jupitermoon]

Here is an attached image of how it turns out! Pretty frustrating

 

[BrianHahn]

The picture helps a lot. This looks like it may be related to roller slippage. Make sure your pinch rollers are directly over the bottom drive rollers. When they are in the down position, the rubber roller wheel should not move if you push on it with your finger. Adjust roller pressure if needed.

This post may be of use as well:

Vinyl Cutter Tracking Quality Parameters Effects and Causes | Cutterpros.com

 

[splathead]

This looks like it may be related to roller slippage.

My guess is no. Notice how straight his weed border is. If the vinyl was slipping, his border would be as skewed as his design. It's the last thing cut.

 

[BrianHahn]

This is very typical of what we see when someone has a tracking issue. The weeding frame doesn't look like it is square. The lines don't look parallel to one another.

 

[splathead]

The weeding frame doesn't look like it is square. The lines don't look parallel to one another.

Yeah, I see that now.

 

[jupitermoon]

Any ideas? Problem still persisting

- Tasha

 

[Blue92]

When was the last time you cleaned the rubber rollers on the cutter and the knurled portion of the drive bar?

Residue and grit can allow the vinyl to move sometimes when feeding back and forth.

Have you checked to make sure the rollers still have a good down force and aren't cracked or loose??

Easiest way I found was to check them to turn off the cutter and insert an index card under the roller. Then pull the card out.

Repeat for each roller. If one is a lot easier than the others you may have found your problem.

 

[BrianHahn]

I like the artwork.....
If you have reviewed the blog post on vinyl cutter tracking and none of those items resolves this issue, it may be that your drive roller has become loose. I don't know for certain on the MH cutters but we had 2 instances on a Creation unit whereby the bottom drive roller lost its connection between segments. If the drive roller on the MH cutter is segmented then it is possible for the connection between the segments to loosen. This will cause the driver roller to not move as one solid bar. To check for this condition, try rolling the different ends of the bottom roller in opposite directions and see if they move with respect to one another.

 

[jupitermoon]

Hello again,
Unfortunately the problem is still persisting. I now have a hugeeee delay in orders and more coming in by the day. Stress levels at an all time high, taking all my energy to not just drop kick the machine into a wall.

I have cleaned the machine thoroughly, the rollers are still tight and work great. I contacted the supplier and they asked if I would use the pen tool to draw out geometric patterns like squares, stars, circles to give them an idea of the tracking problems. The machine drew them perfectly.. not a mm off. But when I go to cut out large images that's when the problem occurs.
So incredibly baffling that one minute it can cut fine and the next is completely off. I am assuming now that it must be a technical fault.

 

[BrianHahn]

It is possible that this is related to slippage in the actual stepper motor when the motor is under load. Could be motor related or motherboard / power supply related.
Can you try this again at the lowest possible speed setting on the cutter? Also, roll out your vinyl in advance so the motors aren't pulling off the roll (lighten the load).
If you like, we can run some of your jobs and send them to you if it would help you out. Let me know.

 

[jupitermoon]

Thankyou for your speedy response!
I am awaiting a response from the supplier.. hoping they may be able to shed some light on the issues.
Do you use signcut? And if so, do you think it could possibly be an issue with the programme?

 

[BrianHahn]

We use SignCut a lot along with DragonCut and Flexi. It is highly unlikely that the issue is related to SignCut. Especially if you have already tested with a pen and it works fine with a pen. This seems to be a tracking related issue which can be caused by a number of possibilities. Try slowing down to the slowest speed and let me know if that works.

 

[jupitermoon]

I'm having a look through the troubleshooting booklet and it says a problem could be "The software setting isn't proper - the tool compensation value is too big"

Any advice as to how I can check this?

Also cutting out something at the lowest speed now - thanks for your help!

 

[BrianHahn]

Again, this isn't going to be related to the tool if the pen plot came out correctly and tracked well.
The two settings you would be concerned about would be the knife offset or blade offset which will impact your corner integrity. Too small a value will give rounded corners. Too large a value will give hangnails. The right value will give nice sharp corners.
The other setting would be overtravel which controls how much of a loop the knife travels beyond the closure point. This is to make sure that at the start/stop point you don't have a little nit of material that didn't cut.
Neither of these settings will impact tracking. If your start and end point of your loops are not in-line, this is a tracking problem caused by roller slippage, motor slippage, material slipping relative to the bottom roller, lack of feedback from the motor to the controller in a servo system, lack of proper voltage / current to the motor due to a poor power supply, etc. The software itself really doesn't control this behavior. The software is telling the cutter to cut a loop properly (as indicated by your pen plot). It is the cutter that isn't executing the job properly.

 

[jupitermoon]

Ok I just used the pen tool of the cutter to draw out the design.... it draws it out absolutely perfectly
then I put in the vinyl, replaced the blade tool and the same problem continues
Any ideas anyone?

 

[BrianHahn]

Did you cut this at the slowest speed possible?