Don’t you need a 42 Amp power supply?
So I was told to think of the ODrive kind of like a transformer. It takes one voltage / current source and converts it to a different voltage and current. It maintains the power though. So the 48V at 21A gets turned into something like 10V at 100A to the motor using PWM. The higher input voltage though allows for a higher top speed (not that I trust the Dewalt’s stock bearings at 80k RPM).
Since you are reluctant to provide us with the location of the rebel base, I have chosen to test this station’s cutting power on your home planet of Alderaan
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Yup - It’s apparently like a switch mode power supply (SMPS) - thanks for reminding me! 
Did you measure the motor’s Kv?
The Dewalt is 1650kV.
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Finally got everything in place to route some Aluminum with the Dewalt. Made this fine piece with the 2L Single Flute Diamond Coated Endmill @Vince.Fab suggested:
(Yes it is a silly little mount for my air blast line)
Then when the cutting was done managed to do this:
The wire got caught in the HDZ while it was retracting. Luckily the spindle was off when it did that. Reminder folks, proper wire routing is your friend.
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So that little mishap drove me to actually get the wiring properly sorted. This included wiring up the motor thermistor and configuring it in the ODrive.
I spotted a vesc being used!
They are pretty handy controllers.
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So Makita has announced the 40V version of their trim router for the US market:
Sadly do not let the “Buy Now” link fool you. It won’t actually start shipping to stores till Mid September according to the sales rep at Ohio Power Tools I spoke with.
What is nice is that because it is because it is 40 volts it means it will be a lower kV rating on the brushless motor of about 775kV compared to the 1600kV on the 18V version. This means it will be more stable and have better torque at lower speeds. Couple that with the new ODrive PRO that has been released or a higher end VESC plus a 48V power supply and it should be suitable for low speed drilling operations all the way up to 35k RPM.
@Vince.Fab are you still using your Makita or has the HDM gotten you to abandon your regular Shapeoko? I would love to see what you could do with this thing.
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I have been reading all I can find about the mod-kita. Is anyone still using the Makita mod set up. I M looking at getting a cnc router and am very interested in using a Makita setup like this. Any starting info would be greatly appreciated!
Hmmmm, how to answer…
Maybe start with, that was then, this is now?
Back then we were modding belt driven SO3 variants. Times have changed, dramatically. I think, in the practical sense, there are better options now.
BUT, if you are looking to mod an old SO3 and like to tinker, sure, it’s a fun thing to do. Biggest benefit to me, back then, was the bump in rpm plus long term reliability.
If, on the other hand, you are considering building your own CNC, your best bet is a 2.2 kw spindle.
But, if you are more interested in making as opposed to reinventing the wheel, one of Carbide 3D’s many options should suit.
I’m still using the DeWalt version of this and have purchased the 40V Makita which I plan on converting when I have the time. The major benefit for me comes from having replaced the SO3’s electronics. I now have full closed loop control over the spindle speed and an RPM range from 1200-40000. With the 40V version’s lower kV value I am hoping to be able to drop the low end down to about 700 RPM though my 48V power supply will limit me to about 35000 on the high end. This will mean I can do proper drilling operations with my SO3.
Another benefit is that I get torque, rpm, and temperature data back from my ODrive Pro which I can graph. @Vince.Fab shows how useful this is on his SMW video.
I agree that the spindle options from Carbide3D are looking rather nice at this point, but a VFD controlled induction motor is less efficient than a BLDC. Meaning you get more horse power for the same wattage with a BLDC motor. They are also more compact. About the only downside is that the cost is definitely higher at this point than just using a stock AC Makita router. It’s hard for me to calculate though as I am crazy and can’t leave well enough alone.
I would love to find a well made industrial BLDC spindle motor to use on my Shapeoko, but till then I am sticking with the DeWalt/ Makita.
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Awesome! Thanks guys! I was also looking at the 40v Makita. Sounds like fun to play with. What size power supply do you think would get full power out of the 40v Makita?
It’s a 48V 1000W Meanwell power supply. I’m controlling it with an ODrive Pro, but that’s overkill. The ODrive S1 should be powerful enough.
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Oh ok ,I might have to get a router and take it to work and play with it. We have power supplies there I can use. I’ll let you know how it goes.
I really need to follow up with you on this, as you and @Vince.Fab were working hard to come out with something for the masses.
Can your odrive setup be used with makita’s brushless router?
My current ODrive setup should have no issues with the 18V or 40V Makita routers. The ODrive Pro and S1 have a much faster microcontroller than the 3.6 I was originally using and are able to update their sine curves far faster. On top of that the Hall sensor code in the ODrive firmware has been greatly improved. What the developer think was causing me issues with the 18V Makita originally was that the hall sensors were not perfectly aligned with the coils. This led to the sine curves being off. Now the firmware checks the coil alignment for each sensor during initial setup.
That said I would still not consider this something for the masses. It requires voiding the warranty of your router, soldiering wires, crimping cables, working with high current, EMF shielding, etc. It is definitely not a plug and play setup.
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Fair enough.
How do you have it wired up to control speed?
Well first I have replaced the Carbide Motion Board out of my SO3 with a Duet 3 Mainboard 6HC (Duet 3D). I have this running in SBC mode which means that it is controlled by a Raspberry Pi 4. The firmware running on the Duet 3 is RepRapFirmware. RepRapFirmware which has an API that allows you to override GCodes with your own external programs running on the Pi. So I have a Python script running that intercepts M3, M4, and M5 codes. It then calculates the RPS (Rotations Per Second) from the RPM value and then connects to the ODrive over its USB serial connection and sets the Spindle Speeds RPS value appropriately.
In order for this to work correctly though I had to purchase a copy of Carbide Create Pro which unlike the free version allows you to create your own post processor. This is important because I needed to add a M400 Gcode (GCode dictionary | Duet3D Documentation) before the M3,M4,M5 gcodes to tell RepRapFirmware to complete all of the cached moves before continuing. This way the spindle does not stop or start spinning at inappropriate times.
Because the ODrive has the precise RPS value set my spindle runs at the precise spindle speed I specify in the GCode file unless it is running out of torque. That does not really happen though as I mostly cut wood.
The same program that is connecting to the ODrive API to control the RPS value is also logging data like the set RPS, the actual RPS, the torque, the motor temp, the MOSFET temps, etc.
All that said, you do not need to go that overboard. Like I have said, I am crazy. The ODrive has a 3.3V ADC on it that can be used to read the PWM signal out of a Carbide Motion Board. You just need to reduce the voltage from 5V to 3.3V with an octocoupler and then pass the PWM signal through an RC circuit to get a DC voltage between 0 and 3.3V. Then you can map the RPS values to use for what voltage in the firmware.