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edsingletary
08-30-2014, 10:26 AM
I am in the middle of a project, I hear the machine stop, simultaneously my heart stops. You know the feeling. I get a message " check cut motor ". Oh no now what, I am thinking. I have an option to PRESS ENTER TO PROCEED. After sniffing around to see if I smelled anything burning I press enter. The machine continues where it left off. Seems fine. No odd noise anywhere, the spindle is cool almost no heat. Is this just something CW does for no apparent reason or should I really be concerned. Do I need to keep spare parts although I have a 2 year warranty or about 150 hours. Any probable cause or a fluke.

rmock
08-30-2014, 11:12 AM
I hate to say this but how many hours since you changed your brushes?

fwharris
08-30-2014, 11:15 AM
Ed,

I am betting that your were doing some type of V carve and this message is fairly common with this types of carves. The computer is looking for the rpms to be at a certain speed. The FIRMWARELOARD gave a good explanation of this a while back. Try doing a search on "check cut motor" for other responses.

Spare parts on hand, you should have a set of back up cut motor brushes on hand (when they get back in stock) and you should be looking at replacing them around 250 cut motor hours.

edsingletary
08-30-2014, 11:54 AM
Rmock I have 60 hours on the cut motor.

edsingletary
08-30-2014, 11:57 AM
FW, I was doing a v carve on lettering, a bunch of lettering. You mentioned brushes, are these a major deal to replace. I'm a good plumber, not a real mechanic though.

fwharris
08-30-2014, 12:02 PM
Ed,

They are fairly easy to replace. It can be done with out removing the cut motor from the machine but to insure proper installation and better inspection of the motor it is best done by removing the motor. There are two screw caps (one on top and the bottom of the motor). Make sure you use a wide/thick tipped screw driver as the slots do tend to strip out if the caps are screwed in to tight.

Digitalwoodshop
08-30-2014, 12:04 PM
What I have found even when doing a vector cut or text is that the machine will stop and give me the check cut motor "CCM" fault at the first few minutes of the carve. I press enter and off it goes... A fairly common error as your machine ages. It has never happened twice in the same project and if I leave the power ON between projects after pressing enter on the first project. When the 2nd project gets to the VERY SAME SPOT that the first one gave me a CCM the 2nd project will INCREASE in MOTOR SPEED at that very same moment.

I had a lot of time to observe the machine doing the very same thing over and over.... I normally turn the power off between projects so I get the CCM with almost every project.

Be planning to do a Maintenance Overhaul at about 250 cut hours... At that time you will change the cut motor brushes and change the 2 inner bearings in the Y Gearbox a set of 685ZZ Metric Bearings. Along with cleaning the machine and lubricating the smooth rails that the machine rides up and down on, the threaded rods and checking head level will give you a Like NEW machine in performace.

If you look at the troubleshooting in the last 3 months at "WHAT Actually went wrong".... It will come down to.... Failure to replace the Cut Motor Brushes as a "Preventive Maintence" item and they waited until they had a "My Cut Motor won't run?" event.... Once the brushes get TOO worn down they can't reach the copper commutator and the motor either stops or starts pulsing as the ARCING VOLTAGE is trying to reach the copper.... This produces heat that melts the brush holder and next thing you see is a post... "Can I buy a cut motor CASE or SHELL?...." Preventive Maintenance at 250 cut hours would have prevented that drama.

Next and most posted about troubleshooting problem is... "My Y is off or not cutting in the correct place?" Again... the most common reason is failure to do Preventive Maintenance.... WE recommend replacing the 2 inner Y Bearings at 250 cut hours.... It returns the Y to a "LIKE NEW" condition as the 2 little Y Bearings are the hardest working parts in the machine in my opinion... Being asked to do a very hard job with the Y doing the most work. The bearings fail then GRIND down the shaft of the big gear as seen in the photo. I believe a future CW "D" version will likely have a redesigned Y Gearbox with a heavier bearing knowing how LHR works to improve the machine over time and likely offer the heavier Y Gearbox as a replacement part... Just a WAG... Wild AL Guess... and wishfull thinking....

The 2nd part of the "Y" issues posted in troubleshooting section comes down to asking the machine to cut PLASTIC when it is designed with a feed rate for WOOD... To cut plastic like the litho's you need to use a NEW LIKE bit as a dull bit will give you problems and the bit will not be able to cut into the plastic in the feed rate being sent by the computer.... A DULL BIT can also give you problems in HARD WOOD TOO....

IF you EVER HEAR Clicking when the bit is over at the bit plate doing it's checks, that is a sign that your Y inner gearbox bearings are bad... We saw a very active "Y" post this week and I believe it came down to worn Y Gearbox Bearings... I was not until the user posted I get a "CLICK" that I knew what the real problem was.... Failure to do Preventive Maintenance sad to say... It took ALL of US including ME to put the Y Gearbox Bearing problem together, I was replacing the Y Gearboxes with 3 I had from the first "Z" Motor Upgrades where you got the whole motor and gearbox. I used just the gearbox on the Y Motor....

So be thinking "Preventive Maintenance" not "Down time repairs made after a failure and you must wait for parts"....

It is GOOD you asked....

AL

Finally got the OK on the final art change and time to put together this $10K order.. got all the parts cut... working the weekend... Life is good...

FWMiller
08-30-2014, 02:10 PM
Check cut motor seems to happen frequently on vector cuts, regardless of machine maintenance. Just a nuisance that unfortunately can't be avoided. As Al said, it rarely happens twice on the same carve.