Brushless Makita Mod (unsupported)

I look forward to seeing the result, in fact I like most of your pics of machined stuff…

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Make sure the motor’s stator core is making good contract with your housing as well. Quite a bit of the heat will be generated there.

I will admit I find it funny that you are basically throwing 70% of this router away and turning it into a custom spindle. You could have easily gotten one of these:

connected it to a BLDC motor, and put it through two good angular contact bearings in a custom housing and gotten the same results.

@CthulhuLabs I’m pretty sure the Carbide pwm is 0-5v. There was a progression to this project. First corded conversion then put tons of hours on it and ran many many pounds of aluminum through it. Worst case it can all be put back to stock without issue and the nice thing is that it is a very compact package for 0.375/8mm capacity. My nomad had a bldc motor (70 watts) and separate spindle stack, kind of a pain to work with two separate spinning things and manage heat/belt drive.

The stator should be a light press fit and the bottom should lock in to prevent spinning in the body.

@LiamN thanks for the support! I’ll most likely get started on it after finishing a drag car roll cage. Gotta pay the bills somehow :sweat_smile:

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There are quite a few Chinese ‘mechanical spindles’ available but I’m not sure they’re balanced well enough for 20-40kRPM.

The attractive aspect of the MakBLDC from my perspective is that it uses volume production parts (therefore cheap) for the housing, bearings and motor but can be made somewhat smarter by plugging in a VESC type controller. That makes it a good candidate for folks who don’t want to go to all the extra trouble of a 3 phase spindle.

My RC Circuit needs tuning, but I got PWM -> RC Circuit -> ADC working. The input from the RC Circuit to the ADC is very fluttery which is causing the Router to flutter as it ramps up and down.

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Another vote for 5V.

Well I had it mostly working. It was still occasionally having issues getting started, but once started it was very smooth… Then my VESC stopped powering on. I think it was having issues which is why the motor wouldn’t start at times. Going to exchanging it for a new one.

In the mean time here is the RC Circuit I was using:

Sorry it looks like a potato. LOL

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edit

Smooth startup 100% of the time lowering the BEMF Coupling to 600. Even though motor detection wants like 1150.

Also would you be willing to duplicate your circuit?

Good news is that at even 2500 rpm, this guy has some tq. Much more than my 60krpm 1.2kw 220v by the feel of it.

PMed you about the circuit.

Do you have it in BLDC mode or FOC? I’ve read warnings about FOC on the 4.xx boards.

I’m in BLDC mode because I cant run a FOC detection (still sensorless), plus ide rather have the rpm over TQ at super slow speeds. I had run this VESC on my hub motor setup in FOC though, worked well.

Decided to give it everything and see what its capable of, pretty solid 2-38krpm. Motor current pulls over 30amps on ramp up to max but it gets there quick!

Bare minimum unloaded

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Your 60kRPM spindle would have less than 1.26 * 2500 / 60000 = 0.0525 in-lbf of torque @ 2500RPM (that’s 1.55Watts).


Your 5A power supply would limit torque at 2500RPM to less than 0.291 in-lbf (8.6Watts)

I didn’t mean rpm for rpm lol. I think I ran the 60k at a 20k min but I rather like messing with the vesc instead of that VFD.

You know I’m not great with numbers @gmack. Just going by feel right now until some real cutting starts.

I would certainly wait less time for the VESC to self-discharge before messing with it than a VFD with 320+VDC on the reservoir caps…

51A * 18V / 745.7 = 1.24HP somewhat justifies the claim that these types of routers have the same peak power as their 115Vac counterparts!

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Just to verify that my router did not fry when the VESC died I reconnected the stock ESC with a slight mod to use my power supply. It did not want to start. After a while of freaking out and troubleshooting, I was able to determine that the hall sensors were not reading properly. Come to find out my dupont crimp connections on the Hall Sensors are not the best and it is not making great contact all the time. Might explain why the VESC was not happy. Think I am going to solder them just to make sure. I blame Makita. They used the smallest gauge wire they could for every wire in this thing.

@Vince.Fab, @CthulhuLabs, @LiamN Please see this other thread for relevant additional info and a question.
@WillAdams, @Julien is there a better way to do this post?

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That’s definitely an interesting thread, even if only for the pics of Vince’s work.

Reading through it, I’m more and more thinking that a real time spindle torque / power readout for the Shapeoko and Nomad is worth trying out.

I’ve got my RS485 to TTL converters, water temp sensors, flow sensor and real power meter to wrap around my water cooled spindle all ordered and on their way from China.

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You couldn’t get it from Amazon?

Unfortunately, not over here, Dr Evil only had ship from China, delivery mid July versions of that unit with the CT and the RS485, eBay had lots of them, all SpeedPak from HK so I ordered one from there.

I also found these which might be a better long term option to add to the DIN rail in my switchgear box.

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Sorry I did not get that. Better way to do what ?

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