[ddexd]

Just got a call from Grizzly. They told me that my machine was part of a batch that did not receive some kind of upgrade and that they are sending me the parts for the upgrade.

I have no idea if this will fix the mill, but if it doesn't they will certainly get a phone call.

[ddexd]

An update on my repairs.

I found several chips on the Control Board and Motor Board that were either shorted, did not meet the manufacturer’s data sheets, or just replaced outright.

The first photo shows the Control Board that is mounted on the mill head. The 8-pin DIP is a Digital Potentiometer (X9C103P) that was found to be shorted between the power supply. This chip is available from Newark or Digikey. I do have a concern that the X9C103P chip will have a shortened life. This chip is being supplied 6 Vdc and the data sheet lists the power supply range to be 5Vdc +/- 10% or (4.5 to 5.5 Vdc), typical for a 5Vdc part. There is one line on the data sheet that lists the absolute maximum voltage as "Voltage on CS, INC, U/D and VCC with respect to VSS ..... -1V to +7V". I suspect the designers of the control board are pushing the chip design.

The other two chips on the board are blown optocouplers (Fairchild 817C). I found replacements at Digikey (NEC 2501A).

Just a note, I installed an IC socket for the X9C103 and the optocouplers to make future replacement easier.

The second photo is of the Motor Board. With thanks to neilw20 I was able to find and get replacements for the 3-socketed DIP IC's. I did find the optocoupler located below the 7-lead IC on the bottom left was blown.

I found the 6 Vdc regulator (LM7806) was also shorted. At least the board designers placed a current limiting resistor on the power supply to the chip. This helps prevent burning up traces on the Motor & Control Boards.

The last two socketed IC's 8-pin & 24-pin were replaced outright.

I'm happy to say all the repairs were successful and the mill is now working. I'm still waiting on the upgrade parts that Grizzly was supposed to have sent me.

I guess if you look at the bright side of the failures, I believe that I have figured out a way to interface the CNC4PC C11G breakout board speed controller output to the SX3 mill. It looks to be as simple as installing a switch to toggle between Mach3 & local speed control and then connecting the C11G analog output to the Motor Board P1, P2 connections and the ground to GND. The P1 & P2 connections are connected together at the Control Board. The C11G would then need to be adjusted for 6Vdc maximum output. Of course you will need to install an isolated 12Vdc power supply on the C11G analog output. I haven't tried the modification yet, but it should work.

Thanks,
ddexd

[neilw20]

Excellent work David!

I am working on a similar fix for transferring the PWM spindle speed control signal and direction bit direct to the motor control board bypassing all the rubbish and the micro on an intermediate board.
Just have to finish tracing out all of the circuits before I commit it to the soldering iron. I will opto-isolate if required.
Target is to get SOLID TAPPPING under Mach3 working. Tacho signals from tacho generator chip will do perfectly, because of cog belt drive.
Probably will use a PIC to perfect this without too many parts. Depends on belt ratio issues.
Due to differences the early and late model motor boards need a different approach. I will do the early, then the later version. (as time permits!)

[Chrisjh]

Hi ddexd,

Sorry about the delay in responding to you call for help. Things have been a bit hectic around here. Most recent problem was loose spindle bearings which I finally fixed this arvo. Tore the spindle out, cleaned and repacked the lower taper bearing and the central thrust bearing with hi temp wheel bearing grease, then made a special tube spanner to tighten the upper M27x1.5 nuts. Used a small hydraulic jack to support the spindle taper while I drifted the upper bearing with a bored piece of 1" water pipe until I had some sort of preload on the whole rotating assembly. Now all the endfloat and dreadful noise are gone.

Looks like you have sorted things out. Your experience with blown digital potentiometer and the optocouplers on the keypad board along with the shorted 7806 Regulator on the main spindle board are classic symptoms of what occurs when the quill height vernier sliding bar shorts out on the rear of the keypadboard. This is a known desigh problem with the Seig/Syil X3 machines. I have posted a modification that I did to my machine to ensure that it does not happen again.

I am surprised that the hall effect sensors on the spindle motor did not blow as well. I have seen 3 machines that have suffered the short out with the digital vernier bar and have been able to repair them by replacing the components that you mention along with the 3 hall effect sensors. I used Allegro A1101 in a 3 Pin SIP Package availabe from Farnell or Newark. The hall effect sensors are connected to the 6VDC rail. This is the power rail that is marked 5V but is really 6V as you discovered.

Another thing to look out for is the pins in the cable end plastic housings sometimes come out of the housing ( they are supposed to be locked in with a small "fish hook syle barb" on the rear side of the pins). I had one machine where this happened and the symptoms were exactly as you described, that is Blue backlighting on the digital LCD display but nothing else. Turned out to be the pins had come out of the housing on the cable running between the LCD board and the spindle board.

Regards

Chrisjh

[ddexd]

Chrisjh,

The damage might have been significantly reduced because I have my equipment plugged into an GFCI. The day I tried to turn the mill on the GFCI was tripped so it may have provided the protection because there were no signs of the control board touching the spindle metal scale.

Thanks,
ddexd

[ddexd]

neilw20,

After studying the newer control board it is very clear that the digital potentiometer is wired to be increased / decreased from the switches on the board. It looks like the Atmel chip toggles the optocouplers that go to the switches to disable the speed control (I need to trace it down).

The output from the digital potentiometer is then just a simple DC signal that is sent to the LM324 OPAMP where it is put through a unity follower before it is sent through the second amplifier where the signal is zeroed and scaled using the blue trim pots located at the bottom left of the control board (see control board in my previous post).

I agree, a PIC could easily be programmed to do the same thing.

Good luck with tracing out boards.

Thanks,
ddexd

[Clayton_s]

Hi guys,

I have a Syil super X3, it has been working fine but the other night the spindle started to randomly stop (as if the estop was pressed). Now when i start the spindle im manual mode it runs, if i increase and decrese the speed or stop and start the spindle it will have random shutdowns like pressing the estop. Any ideas??

Clayton

Melbourne, Australia

[neilw20]

The useless hinged guard is in series with E-stop.
The adjustment at the pivot is not very sound, and can get out of whack.
Mine is in the cupboard.
Protects you from the chuck, but not the tool hanging out.
Are you going to the BBQ on the 23rd?

[Clayton_s]

I removed the guard and its shaft a while ago but the switch and wiring remains intacted? Could this be the problem?
What BBQ?

[ddexd]

The UPS man dropped off the electrical upgrade kit from Grizzly. To my surprise the upgrade kit consisted of the following.

1) New motor with wiring harness.
2) New motor board with wiring harness.
3) New control board
4) New LCD display with wiring harness.

Basically a completely new set of everything electrical except the power cord that plugs into the wall. I do have to say the Grizzly customer service is outstanding.

On a side note, the repairs for the most part work but I have found the following issues.
1) The tapping speed seems to be a little high at 120 RPM. If memory serves, I thought the tapping RPM was about 80 RPM. I should be able to adjust this out with one of the trim pots on the control board.
2) The big issue is, I can press the Emergency Stop button but the mill keeps on running. (nuts) The thing is I can hear the relay energize and de-energize when I push and reset the stop button. I have also measured the voltage across the push button and it is working. I'm a bit puzzled why the mill doesn't shutdown. I may have to trace out the motor board to find the problem unless anyone has an idea or solution for the problem.

If anyone is interested have a rough draft schematic of the control board in EAGLE CAD if anyone is interested in a copy. But I must warn you that the schematic is very rough and I have only made a single pass in putting it together.

Thanks,
ddexd

[neilw20]

Even though you removed the guard the wires thru the switch must be in the closed state. Also the wire crimping on the little white connectors is poor.
Give each one a GENTLE tug. Wrong crimping tool has been used IMO.
Careful not to short anything to chassis. It might cause smoke. Easy to get out. Hard to get back in again.
Also beware of shorts from the digital readout mechanism to the pushbutton board.

Speaking of smoke...

BBQ:
http://www.cnczone.com/forums/showpo...08&postcount=1


Neil

[ddexd]

Just figured out why the mill keeps running even with the E-Stop button pressed. After a couple of hours looking at the motor board and contemplating having to reverse engineer a schematic. I finally decided to check the large blue relay. This is the source of the problem.

Even though I could hear the relay cycle, I assumed the relay was good. Well, I found a data sheet for the relay so I was able to figure out the contacts. I found the normally open contacts to be welded to the common terminal. So no matter what, AC power is gets to the motor controller no matter what the relay / E-Stop is doing and hence the motor kept running.

Now I just need to find a replacement relay and everything should be as good as new.

Thanks,
ddexd

[neilw20]

Hi Dave.

I am interested in a rough copy of the circuit.

There will be an OMRON relay that is a direct plug in.
Is that the blue rectangular relay, on the board that has the motorola chipset? I can dig out a number if you have problems.

Neil

[ddexd]

Neil,

I sent you an email with the schematic. Please let me know if I need to make any corrections to the schematic. And yes, the relay is the large blue relay. I found an Omron relay on Digikey that should work.

Thanks,
ddexd

[neilw20]

Dave.

I just have to find a copy of EAGLE CAD
I normally use my homegrown version, in preference to the horrible pprotel interface.
Same goes for my PCB's

I just export my files to protel for others to use.
Now I must figure the EAGLE CAD data structure too.
Hmm.. another instant project.

Thanks.
Neil

That relay: Beware there are a few different pinouts that look the same.
Measure the pitch carefully and check the contact arrangement.
They also come in normal and sensitive variety, so check the resistance too.
High sensitivity 24v DC coil is about 1100 ohms.

[ddexd]

Update, I de-soldered the large blue relay from the motor board and confirmed one set of contacts was welded together. The replacement relay was a Panasonic model number JW2SN-DC24V. I soldered the new one in and now when I press the E-Stop button, power to the spindle is killed and the spindle stops.

This means everything is now working like it should. It has been a long couple of weeks tracing down and repairing the boards, but now I have spare parts in case of future problems and I believe I now know how to interface a CNC4PC model C11G to the SX3 for spindle speed control.

Thanks again for everyone's help.
ddexd

[presslab]

I too had problems with my old electronics, shorting on the scale. Here is a list of components I had to replace:

Main board:

Designator Package Replacement part
7806       TO-220  ST L7806
Q1         SOT-23  MMBT2907
Q2         SOT-23  MMBT2222
Q3         SOT-23  MMBT2907
Q4         TO-92   PN2222

Motor:

Quantity 3 hall effect sensors. Old part number was UTC U18, replaced with
Allegro A3280.

http://www.utc-ic.com/spec/U18.pdf

Front panel board:

Designator Package Replacement part
R22        1/8W TH 47 ohm
U3         SO-14   ST LM324
U2         DIP-8   X9C103P
U7         DIP-4   Fairchild H11A817C
U8         DIP-4   Fairchild H11A817C

I since have received the upgraded boards. The circuit interface is quite different between the front panel and the main board, it is some kind of synchronous serial interface and it seems like it is polling the pushbuttons.

In my journey to upgrade to CNC I have come up with a plan. The Syil spindle board is not the best because it does not have fast ramp times and I'm unsure how good semi-rigid tapping will work with that. I don't really want to use the old main board as it is pretty dodgy. I occasionally had to whack my e-stop relay to get the machine to work and it does not have isolated inputs.

My plan is to use an aftermarket brushless amplifier for the spindle with analog inputs. The old front panel controller should work with this and I can also easily interface it to Mach3. With the addition of a simple relay I can select from the front panel or Mach3 control.

[neilw20]

I have been designing BLDC circuitry upto 2KW so I am comfortable renovating the existing unreliable,cobbled together lot.
I have used the the MC33035, MC33039 controller setup and they work really well when implemented correctly in proper current mode with slope compensation, and proper PID design of the speed/power control loop.
You can even dynamically brake the MC33035, which goes towards solid tapping....

I am going to come up with a fix on the whole thing, including some new small control boards. The interface system lost the plot when it went CNC.
Before that it still sucked.

[presslab]

That sounds like a fun project. I'd like to see what you come up with.

I too have designed some BLDC servo controllers for work, around 500W, with CANbus and s-curve velocity profile generation. Right now I think I can find a used brushless amplifier on ebay for $100 or so, and that's my plan.

With one of those amps, a SSR for estop, a relay for switching from manual/auto control, and a few discretes I think I will have something.


Another thing worth noting is the spindle motor. The "old electronics" motor has a voltage rating of 110V, and the "new" one is 220V. The RPM listed is the same, 3500 RPM. The old amp must have driven the motor differently or something.

I think I will switch back to the old motor, and with a aftermarket amp I should be able to get some more spindle speed. This is better than a pulley change because I will still have low speed torque.

[ddexd]

As far as spindle speed goes, I did notice when I was making repairs to the control boards when I bypassed the digital potentiometer that I could get the spindle speed up to 2500+ rpm. With a working digital potentiometer installed the maximum spindle speed is only 1730 rpm.

Neil, definitely would like to see your board design to replace the standard SX3 control boards.