If you have had lots of weired problems read this!!!

[Jeff_Birt]

I had the now infamous Z-axis encoder problem shortly after getting my machine and just had my board sensor die. After talking with 'The Bard' on the phone tonight things got stranger (which is no reflection on 'The Bard ).

I think many (most ) of the severe problems the newer machines have been having may be traced back to this cause. After I got off the phone with the Bard tonight I flipped on the machine to check again to see if magically the board sensor was now working. It came up in accessory mode, which was wierd. I went to the sensor test menu and NOTHING was registering, the cover switch , the pressure roller switches, nothing was changing state when actuated. Wierder and wierder, since I was eating supper when he called I went back in the house and finised eating. I came back down, looked at the board sensor again, check the wires, yep they looked like they were in the black channel. Turned it on again and got only black squares on the display!!

So now I am REALLY curious what is going on. I shut it off, pull the memory card and turn on and all black squares (which I expect as the black squares are caused by the LCD not getting initialized). I pop the card in my computer, fire up Designer and it reflashes the card with 1.115 (I then put 1.117 on it). Back out to the machine, put in card, display comes up in Accesory mode again (like the probe is plugged in).

So, feeling a bit jinxed, I unplug the small ribbon cable leading down to the home sensor/probe connector. The machine will now fire up in normal mode but it is still not reading ANY sensor! This makes me really suspicious, I remeber hearing on the forum that someone else had the phantom accessory mode display that vanished on its own.

Now knowing that the strangness came about after cleaning the board sensor and 'The Bard' kept stressing 'unkinking' (more on unkinking later) the cable, coupled with knowing that kinks won't cause any problems by themselves, BUT having sensor wires shorted to ground/each other can really freak things out. I pulled of the Y-truck and found a pinched wire (see pic). I removed the cable and the pinched wire pulled promtply in two (a good sign of how badly it was pinched). I solderd it back together and plugged everything back in without reassembly.

So with the wire not shorting to the machine frame the board sensor works (was reading 136 just held sort of close to the machine), and all the other sensors worked and the machine came up in normal mode.
I now suspect that the board sensor wires getting pinched are causing a majority of problems with these machines. If you consider all the strange symptomns that can be caused by all the machines sensors becoming meaningless during operation:

1 ) encoders will loose count, axis will go crazy
2 ) the flash card will be scrambled (users getting no display on new machines)
3 ) machines that are repaired and shipped back failing shortly after arrival

If a wire gets pinched it will very likely result in it becoming open or shorted at some point. Striaghting it out will not result in a permenant fix. It should be repaired and a solution found to prevent the reoccurance of the problem (like redesigning the plastic cover channel, or silicone the wire in the channel {not the black stuff that was on the connectors originally}).

So, if you have been having some of the strange problems listed here I would suggest checking the board sensor cabling. EDIT: This is not a job for everyone if you do not have a lot of experiance with this type of work it's best left to the guys at CW, so give them a call.

[HandTurnedMaple]

I had the now infamous Z-axis encoder problem shortly after getting my machine and just had my board sensor die. After talking with 'The Bard' on the phone tonight things got stranger (which is no reflection on 'The Bard ).

I think its the most reflection of the Bard I've heard.

[toothpicks]

Holy frijoles, Jeff! Good find. I can't tell for sure, even after blowing up the pic several times. Was the pinch just to the left of the channel, right under where the bearing is removed?

[The Bard]

*glows with strangeness*

[Jeff_Birt]

Toothpics, yeah that's wher it is. I should have placed a circle around it (I'll do that in a bitand maybe add a closeup). It looks just like a little bump. The wire was only out slightly but it could not be seen with the Y-truck in the machine.

[dcozort]

Jeff,,,, Would this cause the z-truck to plunge through the wood .... Like many of us are experencing...... The reason I ask is my first error was a clear board sensor after removing sensor I found kinked wires fixed them by unkinking .... My sensor read 116... I then carved a few projects just fine and then out of the blue z-truck dove durning a carve.... So I began checking all sensors all checked good except board sensor it was back down to 40 or less at times..... I have not done anything further except call C/W for a new Z-Truck motor....... Chris said once this condition started the machine would keep doing it.... Do you think I need to pull the Z-Truck and check...... Dennis

[Jeff_Birt]

Dennis, I do indeed believe that intermittant shorts (to machine frame) in this wiring harness can be casuing Z-axis problems. There is no practical way to tell if you have a problem with this except through inspction. (It could be Hi-potted if you have one and you disconnect the electrics). Your symptom of a clear board sensor error (did you take a reading), that was 'resolved' by 'unkinking' the wires sounds suspicious enough to check.

It is an involved process to check as you have to pull the entire Y-truck/Z-truck assembly off. It is not hard to get apart but adjusting the bearings can be a bit tricky. You might want to call CW (or PM 'The Bard') to see if they have a PDF guidline for this R&R (remove and replace).

[The Bard]

we don't and I don't expect we ever will.

We tend to frown upon people removing the trucks as they have a definate "sweet spot" to get back on. Once you remove the trucks, you can seriously damage the machine when starting again if they're off be even the smallest amount.

but of course, I'm an idiot.

[Jeff_Birt]

"The Infamous and Illustrious Bard says"

but of course, I'm an idiot.

Bard, I didn't know we belonged to the same club I got in by way of nomination from my spousal unit.

[The Bard]

The worlds shortest Fairy Tale:

Once upon a time there was a young man who fell in love with a young woman.

He asked her to marry him.

She said No.

And he lived happily ever after.

THE END>

*bows*