Refine MH721 cuts unstraight rippled and wavy lines

[billy80808 0]

I just got this cutter a couple days ago, but since the very first cut its had rippled lines (lines as if a dull blade were to drag across a sheet of vinyl) and wavy lines. It is USB connected, never taken apart, grounded (screw holes sanded to bare metal then grounded), and i use SignBlazer. Ive adjusted the blade so it doesnt cut too deep into the vinyl, adjusted the offset in SignBlazer to .20, .25, and .30 , adjusted the cut speed to 200 mm/s, cut press to 200g, and i even replaced the blade (but still kept the old one just in case it isnt the blade). I really want to get into diecuts so can anyone help me out? ANY type of help or even "idk bro, good luck!"'s would even help lol. Thanks! I also hope this helps anyone else with the same problem!

Heres pics of the ripples and waves:

[billy80808 0]

BTW: I also took apart the Blade Holder to add a drop of light oil into the blade area itself and i noticed that there was possible rust inside. After i put the light oil, i shook out the extra and i noticed the extra that flew out was a tanish brown with very fine brown flakes and even after the oil, the blade still spins somewhat roughly. Need a new blade holder? I would think that the blade might lock up from the rust at certain degrees and may cause my ripples.

[cowboy_1_831 28]

Maybe take a pipe cleaner or something similar and clean it out then retry.

[billy80808 0]

Maybe take a pipe cleaner or something similar and clean it out then retry.

Ive done that and it still gives the same results. Ive also relubed it with the light oil several times today and its much smoother now. Yet i still get the same results on the vinyl.

[billy80808 0]

UPDATE**

Okay so ive just cut using the Pen and the lines have wavy and rippled lines. I also felt the pen holder and plotter itself while it was plotting and it vibrates A LOT. not so roughly but enough to mess up my lines on both paper and vinyl. Do i need to buy a new plotter thing? tighten a belt?

[MZ SKEETER 4,720]

have you made sure that the carriage head is firmly in the track? The white wheels should be firmly in the track...

from support:

Bad cuts

Posted by - NA - on 28 September 2007 08:36 PM

Sometimes during shipping the carriage will pop off of its tracks which would cause poor cutting. Make sure the little white wheels behind the carriage are seated ON the tracks and not in front of the tracks. To reseat, just press up on the spring loaded carriage, and it should reseat without much force.

[arty-rc 719]

When my mh-721 started to make "ripple cuts" I tightned every nut, bolt and screw that I could find. I also removed the plastic cover on the blade carriage and snugged up all the hardware inside. My cuts were better after that.

[billy80808 0]

@arty-rc can you upload a pic of where you tightened the nuts and screws on your blade carriage? i just checked all of mine and its cutting a little better but still kinda vibrates

[arty-rc 719]

@arty-rc can you upload a pic of where you tightened the nuts and screws on your blade carriage? i just checked all of mine and its cutting a little better but still kinda vibrates

I gave my 721 to my son in KY after I bought my Graphtec so I have no way of taking a picture for you. Just tighten any and all the screws and bolts that you see. Also, put some padding under the cutter where it sits on the stand. That will further reduce the vibration.

[jkess 0]

Hi,

 

Did you ever resolve this issue? I am having the same problem and just tightened all the screws, checked the white wheels, and even tried a brand new blade just for kicks. Nothing seems to fix it. Any help is appreciated!

 

Jordan

[Dakotagrafx 7,298]

Hi,

 

Did you ever resolve this issue? I am having the same problem and just tightened all the screws, checked the white wheels, and even tried a brand new blade just for kicks. Nothing seems to fix it. Any help is appreciated!

 

Jordan

how did you adjust your blade depth?

[jkess 0]

I took a piece of scrap vinyl, pushed down, and cut. Then I adjusted the depth until there was barely a mark on the backing paper. I've tried other methods of setting the blade depth too, like cutting through a stack of post its and adjusting so it only cuts through the first one.

[jaybyrd 3,770]

The scrap vinyl is the right way and the reason is that different vinyls are different thicknesses and this way you can adjust to the vinyl you are using.

[Dakotagrafx 7,298]

please post a picture - if like a zipper it probably needs a drop of light oil in the holder - if wavy it can be a slew of things.

[vinylmonkey 0]

I know it's naughty because this is thread necrophilia, but I've registered specially!

I have an MH-721 and had a similar problem. I've had my cutter for a couple of years now and it's always been brilliant (obviously, I've changed the odd blade but nothing else) until I had a jam the other day then it stopped cutting properly - faint lines and skewed lines.

 

So I took the advice in the thread - tightened all the screws (a couple loose) and then spotted a white wheel slightly off the track.

 

Hey presto, working cutter (now to sort those 30 odd t-shirts I have to do imminently).

 

So I'd like to say thanks, and often old threads are still the best!

[slice&dice 2,467]

Ahhhhh, the white wheel off the track !!!!  That'll do it.

 

And, while not the solution to your particular issue, there is also an option to check the belt tensioner, which is located under the left-hand housing (the one with the power plug).

I had an SC cutter that was jittery, and a few turns of the screw on the tensioner got the belt tighter and resolved the problem.

[rlucio210 0]

would this be the same as on a 871 - mk2 mine started doing the wavy and rippled cuts. not sure what is causing that the wheels are on the track and all

[Dakotagrafx 7,298]

would this be the same as on a 871 - mk2 mine started doing the wavy and rippled cuts. not sure what is causing that the wheels are on the track and all

80 percent of the time that is too much blade exposure - about 15 percent the blade holder needs lubed or replaced - then there is the other 5 percent - 

[rlucio210 0]

80 percent of the time that is too much blade exposure - about 15 percent the blade holder needs lubed or replaced - then there is the other 5 percent - 

 

 

when you say blade holder do you mean the silver holder the whole thing?i have only hadthe machine a few months

[Dakotagrafx 7,298]

did you set the blade with skeeters directions/?  did you change the blade to see if maybe you have a broken tip?

blade holder is the part that holds the blade yes

[rlucio210 0]

did you set the blade with skeeters directions/?  did you change the blade to see if maybe you have a broken tip?

blade holder is the part that holds the blade yes

 

 

it had been cutting fine butthen it started to go crazy lol i replaced the blade and still doing it

[Dakotagrafx 7,298]

how did you adjust the blade?

[rlucio210 0]

how did you adjust the blade?

i used a piece of scrap vinly and cit circles in it enough to where it didnt go through the backing

[Dakotagrafx 7,298]

so that should be close  = did you try adding a drop of lightweight oil to the blade holder so the blade spins freely?

from our friend skeeter
 

To start with, you should set your blade depth correctly, by taking the blade holder out of the machine, and firmly cut across a piece of scrap vinyl, you will be cutting. You should only be cutting the vinyl and barely a mark on wax paper backing, Adjust blade to get there, Then put the blade holder back in machine, and use the force of the machine to get there, same results, only cutting the vinyl and barely a mark in wax paper backing.

[rlucio210 0]

can i ask what cut speed and pressure you guys are running?