Thread: Another chinese CNC router

Got the motor covers today so there's no excuse not to get the CNC router actually running 'real soon'.
Once I get these on the motors and wired up (4 pin plug/socket provided), I can make up the cables to connect them to the G540. I'll be using these connectors from Homann Designs

It's necessary to drill out the mounting holes to suit the motor in use (NEMA is apparently not standard in that respect) but the screws are provided and it will be the first job for my new drill press!

EDIT: Struck a small snag, I can't get the knob off the stepper motor shaft! The motors are dual shaft and have a knob for manual movement.
I'll have to make/find some sort of puller tomorrow (too cold in the shed tonight and there are rats ...)

If there isn't a grub screw holding them on then they might have been loctited there.

There is a grub screw and even after removing it, they're stuck fast.

I can only hope that Loctite was not in the manufacturers budget - seeing they've 'economised' everywhere else.

Originally Posted by snowyskiesau

There is a grub screw and even after removing it, they're stuck fast.

Make sure they haven't put in two grub screws, I've seen that before

Warrick

That sounds promising then. It is probably where they have cross drilled and tapped into the bore for the grub screw and they haven't removed the burr causing it to be tight. A puller should do the trick and you could easily make one from flat bar if you don't want to spend money - that assumes you have a set of taps.

You're right about the loctite - I should have said clag glue.

I had rats last year and it was really difficult getting rid of them - crafty little varmants. I ended up getting a motion activated tazar trap from Derwent Traders in your part of the world after many weeks of trying with breakback, elliot and other methods of eradication. It was the neighbours cat that finally did the trick for me - before that I had discouraged any cat going on my property. Dog biscuits, a fruiting palm tree and snail shells found in the abandoned nest which I only discovered a month or so ago.

Yeah Warrick is right - he means one on top of the other - nice little trap that one.

Only one screw

I'll try the puller option tomorrow. Failing that, I may have to saw them off

The only way I know to loosen Loctite is with heat and lots of it, not the best solution for a motor.

If you don't need the dual shaft you could cut through the shaft with little risk of damaging the motor. Come back on the ally wheel and keep cutting through the lot. The little bit left should be easy enough to remove.
I think you will find the puller will work.

I hadn't thought of cutting the shaft off but that's a good option and probably easier/neater than trying to cut off just the knob.

Once the plastic covers are on, you can't access the shaft anyway so its loss will not be missed.

i breed birds , and have a huge rat problem , 180kg of bird seed a month feeds them up well , the best method ive found is snakes , but then snakes become a problem , so have set up a few Crab pot "snake / rat traps" , with 1 inch mesh , put bird seed in the trap + water , rats go in cant get out , snake go's in and if over size get stuck as well , any snakes over 4 foot get removed ( 4 a year ), very few rats , the carpet pythons i have are fine , they will also fight for there territory from other snakes (poisonous ones )

Finally back to the CNC router! Any number of things have kept me out of the shed but as I'm officially fed up of making sawdust, time to tackle this again.

Tonight I'm going to wire up the new cables, plug for the motor cover and 9 pin plug for the G540.
The Gecko connectors use A+ A- B+ B- to indicate the coil pairs and polarity. I Can work out which wires are pairs on the motor but not their polarity.
Does anyone know the colour coding for the 6040 motors?

Does it really matter? As long as all the cables are wired the same, I guess I can make any directional changes in Mach 3.

As you conjecture, it really doesn't matter too much which way round they go but you should be able to find out from the motor numbers what the correct way is. If you should get it wrong you may need to swap a wire around.
Just do a search for those particular motors.

This may do the trick. It is standard wiring for a Nema17 motor

Probably should have also said:

• The motors are labelled 57BYGH636-41B, a search reveals no information about them other than they are 3A (that's on the motor)
• Motor wire colours are Blue, Green, Red, Yellow.