Knife drags

[CSLESTER 0]

I am new to plotter operation and am having a problem.  When I  cut the knife only drags.  The holder does not appear to lift or make any vertical movement at all. 

MH721 cutter  Signcut software purchased ebay in early march

using serial port on an older computer running XP

Any suggestions

[kenimes 42]

You might see if you can manually move the arm up and down. It does not move alot, but should move up and down a bit. Try and run a self test by pressing the TEST button on the cutter itself.

Ken

[CSLESTER 0]

I have tried the test thing it runs and will move horizontally.  Here is where I stand.  To get the knife to cut vinyl (oracal 651) I have to adjust the knife holder so the blade is almost fully exposed and select 400 for force.  When I do this the knife does not lift between letters or shapes. 

To describe the blade carrier, it feels like it is floating. not much upward travel distance when lifted with a finger and lots of travel capability downward.  I guess what I am saying is that I am not getting any downward pressuere applied only cutting by dragging the vinyl under a statically positioned knife.  Example:  The letters are cut in a four letter word and when the knife returns to the point of origin it drags the cutting across the letters.

Still looking for a solution

[TaterNuts 3]

You shouldnt have the blade out that far just to cut vinyl...

I believe what ken was trying to say is, when you press, and hold, the 'test' button, does the blade holder go down to the vinyl?  BTW, if you have the blade out as far as you stated in the previous post, it probably wont move.

If you have the blade out too far, and it is touching the vinyl in the idle position, that somethings really not right.  The blade should extend no further out of the blade holder than the thickness of vinyl... 

I would adjust your blade down in the holder alot till you can barely see the tip, try to cut out some letters or something... Watch the blade, does it move down to touch/cut the vinyl???  If it doesnt move to cut the letters, Something is way wrong.

Try it and let us know the results

[CSLESTER 0]

I set the blade in the holder as suggested...just barely exposed and dropped the holder in the fixture

I then pressed and held the "test" button...there was no movement until I released the test button and then the test pattern runs.  I am set at 8 for speed and 100 for force.  After the test run completed I moved the carriage assembly and attemped to pick out the cut test area.  The vinyl has been scratched, but not cut sufficiently to pick out any portion of the test pattern

[TaterNuts 3]

Hmmm... got me fooled....  I really have no idea what is going on... Dull blade maybe?  Did you try a diffrent blade?

[CSLESTER 0]

Tater, I really appreciate the thoughts and help.  Yes, I have changed the blade.  I set the force to 400 and did the test thing again,  the vinyl is still only scratched not cut, 

I am close to "at a loss." The only thing I can assume is my machine has insufficient downward pressure,  in other words it is broken

Can anyone suggest a tech rep I should contact at USCutter?

[TaterNuts 3]

I would say marcel at us cutter, but he is no longer with the company.  I would PM kenimes or email him...

http://uscutter.com/index.php?option=com_smf&Itemid=99999999&action=profile;u=460

[marcuso 15]

You should need downforce of about 50, not 400.  You said that you drop the blade into the holder.  If you apply pressure to the blade, does it stay in place, or does it go down into the holder?  If it is simply a blade holder problem, we would be happy to replace it.

[CSLESTER 0]

Marcuso,

The blade moves freely into the holder when dropped in.  After depth adjustment if I use a fingernail to press on the exposed tip of the cutting blade it remains in place.  When I push on the silver plunger the blade is exposed further and retracts when released.

[JustMe 0]

Sounds as though you are having the same problem that I had but I got it resolved by myself. When you drop the blade into the holder be sure to adjust the brass knob up as far as you can first which will the allow the knife to be to far downward and knife then tighten the silver metal screw afterward continue to adjust the brass knob until u have the blade at the right adjustment . I thought my bladeholder was broken but that is not your problem don't spend any mopney yet. 

[smoovlatino 0]

Be sure your machine is OFFLINE when you drop the blade holder in and secure it.  If the machine is ONLINE when you secure the blade holder, you have set the position of the blade while cutting - IE: that is the amount of force it will use (plus or minus the downward force adjustment) as this is the position the machine uses as it engages the vinyl.  Let me know if this fixes the problem!!

[Beardown 0]

The blade itself coming out of the holder should be the same as credit card width ...only half that