Breaking bits

[GVigue]

There is a glitch in the software because I have opened my cover and the bit stop spinning but the program kept running and the bit broke. I had to hit the stop button to stop it. This has happened just once but it indicates a problem in the software to me. The cover safety switch should be hard wired to stop all motors, not just the bit. The software would have to back up a few steps when restarting the project because of the delay in receiving the input signal but that is easy to overcome. Unfortunately it seems we have to purchase the Designer upgrade to get any firmware fixes for the machine. Someone correct me if I am wrong please. If that is the case this won't likely be fixed unless you buy the latest or a future Designer upgrade. I suggest that you always hit the stop button before opening the cover to be safe.

[dbfletcher]

There are two micro switches on the cover... one is the return path to the cut motor... and one is the "cover open" switch. It should like your cover open switch isn't working correctly. If that switch was faulty, I believe you would see the exact symptoms as you describe... you life teh cover and the cut motor stops.. but everything else keeps going.

[GVigue]

Well that does make sense Db but it does show another problem with the design. It indicates to me a poor execution of the software and safety switches. They should have used magnetic reed switches or other type of sealed switches given the environment they are in and as I mentioned earlier they should be hard wired to cut off all the motors. Safety switches should never be software controlled. Dividing the task between two separate switches is a bad idea too. One switch will always lag the other which could cause a timing issue especially since the software cycle is very slow - "could be more then 1/2s to process a signal"?. Two hard wired switches in series would have provided redundancy however. This would have saved me a bit as well as the OP. Now I have less faith in the cover then before :P

[CW-HAL9000]

You will be told for safety sakes to leave them alone but I bypassed the two cover switches in the first month I owned my first machine. I just push stop if I want to stop the machine. Anyone who opens the cover and sticks their hands in while it is running deserves the ouch they will get. LOL.

[mtylerfl]

Well that does make sense Db but it does show another problem with the design. It indicates to me a poor execution of the software and safety switches. They should have used magnetic reed switches or other type of sealed switches given the environment they are in and as I mentioned earlier they should be hard wired to cut off all the motors. Safety switches should never be software controlled. Dividing the task between two separate switches is a bad idea too. One switch will always lag the other which could cause a timing issue especially since the software cycle is very slow - "could be more then 1/2s to process a signal"?. Two hard wired switches in series would have provided redundancy however. This would have saved me a bit as well as the OP. Now I have less faith in the cover then before :P

The switches are mechanical, not 'software controlled'. Also, the original design had sealed switches. You can thank Underwriter's Laboratories (UL) for forcing CW to use the switches you see now. The folks at UL thought 'their approved switches' were better.

In any case, it is important to clean the switches every now and then. Blow out with compressed air and a squirt with WD-40 if necessary. If they were sealed (like CW originally designed) we wouldn't have to clean them at all. Thanks again, UL!

[RMarkey]

"could be more then 1/2s to process a signal"

This is for the rpm sensor, not the cover switch. The cover switch is instant and raises the head immediately.

[fwharris]

The proper way to "pause" a carving is to press the stop button ONCE. Doing so tells the computer to halt/stop all operations at the same time so you will not have that delay that you get when you open the clear cover.

[GVigue]

Metalus, if that's the case then this should not have caused the broken bit for the OP should it? The head would have raised the bit when the switch changed states thus saving the bit? I dunno... too much contradicting info here lol. Mr Tyler says the switches are mechanical only. I had assumed at least one was software controlled based on the previous comments. It appears that there is one micro switch on each corner of the cover so I can see how if one corner was raised a little the other switch may not detect it. A double pole switch at one location would make more sense in that case. I do agree; UL has some wonderful ideas! Maybe Mr Tyler could tell us which switch was in the original specs? I would like to replace mine next time I clean the unit. It might be available in a double pole version too. CW-Hal has a point too... The cover should be backup for emergencies only and not for daily use. Pressing the stop button is safer.

[mtylerfl]

I have no idea exactly what the original specs were...this information about the original sealed switches and the UL swap was shared publicly by a CW Hardware Engineer during a presentation at a CW Conference two years ago.

In any case, the switches are mechanical and the 'power off/on' status is detected by the machine controller (software?). No matter...it is what it is and we just have to deal with it. I'm very sorry you broke a bit, but FW is correct...the lid opening to stop the machine is only to be used in an emergency situation - which could potentially lead to bit breakage due to the impossibility for both switches to disengage at precisely the same time. In non-emergency scenarios, use the Stop button on the keypad and you won't run the risk of breaking anything.

EDIT: Please call me Michael or MT or anything except 'mr. tyler' ...I feel old enough already

[Digitalwoodshop]

The left switch likely was jammed with sawdust and that is the reason it never released and the computer never got the message to do it's software routine of stopping the Cut Motor Electronically AND Raising the Head.

The purpose of the right side Cut Motor Return Path Electrical Safety Switch is a Backup to the computer in stopping the Cut Motor when the cover is open. The computer turns off the Q1 Transistor Switch on the X Termination Board. That Q1 is the electrical on off switch.

As said before, the Right Switch is just a backup and it did it's job of stopping the Cut Motor when you opened the cover. Because the Left Switch stuck the computer never got the word to stop. So it is nothing to do with the software and having to buy something "soapbox".... Once you understand the machine and what happened it is not a sotware fault.

It is sad that the bit broke but I would rather hear about a broken bit then a mangled finger.

This just comes down to knowing the machine and being ready to react when we see something unusual like opening the cover and the head keeps moving and a little luck. This SAME thing happend to me with the more Robust Carving Bit once years ago and my only option was to quickly turn off the power switch before something broke. I got lucky.

I would recommend a replacement of the switch and recommend the LHR version. Retro fitting a aftermarket switch could result in another broken bit if not installed properly.

Remember you can always test the left side switch with Sensor Data on the LCD. The right side switch cannot be monitored on the LCD, it is just wired on the return path to the motor.

Transistors, SCR's, Triacs, all power control devices like the Q1 on the X Termination Board have been known to fail and they either fail open or shorted. When Shorted they would start the Cut Motor. With the Cover Open, the right side switch would prevent the motor from moving. Had someone bypassed the Right Side Switch and the Q1 Failed the Cut Motor "Could" Start as you were changing bits.... BY BYPASSING the Right Side Safety Switch and just press STOP you are putting your TRUST in the Q1 Transistor NEVER FAILING and turning the Cut Motor ON while you are changing the Bit.... It's like changing the Fan Belt on your Car while you Child plays in the Drivers Seat with the KEYS in the Ignition..... He or She would never turn on the Key.... RIGHT...

If you search out old posts around the time the pictures were taken shown below with the C1 Capacitor Snapped off one end you will find posts where the Cut Motor came on without even running a project.... cover closed, tap on top of machine, C1 bounced and Q1 Turned on... It was like using a paper clip to short over the transistor turning on the Cut Motor. I had 3 of my 4 machines have the C1 Snap.... That was WAY back in the QC Days when I ran a BAD QC long after it was BAD and vibrating not knowing... The Vibration broke the C1 Cap... They are glued now.

So with all that knowledge, you can make an informed decision as to if you want to bypass ANY safety switch. Knowing you could loose your fingers over it.

AL

Here are 3 old posts as "I" was learning the machine and also learning that a few of my "Guesses" were wrong.... The Cut Motor HAS been shown to be able to RUN BY ITSELF.... So beware bypassing any Safety Switches..... Here is proof from 2008.

Here is the first post in 2008 with the Cut Motor running by itself... http://forum.carvewright.com/showthr...=Motor+running

And http://forum.carvewright.com/showthr...=Motor+running

And months later AGAIN... http://forum.carvewright.com/showthr...=Motor+running