The cooked MAC repair thread!

[neptronix]

If your stator is toast, let me know. I've been meaning to upgrade to a 10T motor lately.
I've got an 8T stator in pristine condition.

[Spicerack]

If your stator is toast, let me know. I've been meaning to upgrade to a 10T motor lately.
I've got an 8T stator in pristine condition.

Thanks, I'll bear it in mind!

[Spicerack]

That looks brutal

I'd suggest testing continuity from the end of the hall cable to the pads for the hall pins to make sure they all made a connection.

Did it BEFORE I did the epoxy!

There isn't much clearance for the wires and they tend to rub against the rotor. I like your epoxy approach to hold them down. I hate stuffing the wires though that 90 deg. bend in the hole. I wish they could have run them in a slot along the outside of the axle like an X5 motor.

I was tempted to make a ring of holes in the rotor that sort of line up with the windings to allow air to pass through. If there is enough clearance, there could be some vanes along the edge of the holes to turn it into sort of a fan when it spins. This would help tranfer heat away from the windings and to the outer case where it can be dissipated.

Oh yeah, forgot to mention that. I lathed the rotor to give it a little bit more clearance for the windings- although won't be a drama as I won't be getting it that hot again! I also drilled a series of holes in the face of the rotor- I'll chuck up a photo when I can. There will also be cooling holes in both covers- with filter mesh across them to stop too much dust etc getting in to the gears. The disc side will have little scoops on each hole to act as a fan and help move air through the motor and out on the freewheel side. I'm also considering whether to clear out all the grease for the gears and carefully apply graphite instead as the lube. Not sure if that would work or not.

[kfong]

I thought those shafts were hardened. Looks like you had no problem drilling them out. Did it take long, I might do that with mine one day.

[Spicerack]

They are surface hardened- you need to break through the end of the axle but pretty easy. Once you're in the main shaft it's easy going as long as you have a set of long reduced shank drills- as soon as you drill into the axle past the flutes on the drill bit it will seize up.... I know from personal experience and it's a PITA to get the drill out!

It took me about 45 minutes on my lathe to drill it out using successively larger bits- but that also included some drill extraction time and then machining down the shanks on the bits.... If I were to do it again it would take 10 mins max, but only on a lathe. I wouldn't even attempt it any other way.

[Spicerack]

New controller and CA on the way- thanks Cellman! This is the difference by buying from people like Paul- you actually get customer support...

[Spicerack]

Just did a quick and dirty phase/windings check on the motor.

All three phases disconnected, motor spins fairly easily.

Hook any of the phases up to another and you get alot more resistance to turning. Exactly what you would expect. All combinations of shorting the phases are the same and alot more resistance than when the phases are not connected together. I'm happy that the windings are all ok on the motor

[stripedtuna]

That's awesome news mate..

Is there anything you can do (in the way of fuses etc.) to safeguard the new controller for your first test, just in case? Or do you just hook it up and give it a whirl?

Looking forward to seeing a win on this one.. Awesome work mate..

cheers.

[Spicerack]

I've got a motor and controller tester (thanks Aussiejester) here so I'll test it all out with that first. TBH, I'm pretty confident that the motor itself is now perfect- new halls, new phases and a temp sender on the windings. No point putting the sensor on the 10g phase wires as they simply won't be getting hot- the windings will if there's too many amps going in.

Yes, I can't wait to get my new controller! I've got a sore ass, chafed thighs and a healthy dose of cycle rage from inconsiderate car drivers cutting me off/pulling out infront of me, passing too close etc. Seriously, who would actually pedal a bike?

[jateureka]

subscribed

[Spicerack]

Couple of progress notes:

Changed the thermocouple over to one with more range- I now don't know how well done my roasts are... If the wife asks where the meat thermometer has gone, YOU HAVEN'T SEEN IT!



You can see the new little thermocouple above...

This is the display part- used to be part of a pen shaped temp probe. Goes up to 170+ celcius- way above my hall cooking temp! The previous one only went up to 70 so that got re-assisgned to shed duties. Yesterday I was happy to confirm that my excessive sweating was caused by a shed temperature of 41 celcius, not some rare disorder. If Doctorbass is reading this, feel free to send some snow my way- il fait tres chaud ici!

The probe is very similar to this one: http://www.ebay.com.au/itm/180780023952?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649





I also had two parcels arrive today- one was the motor tester- $25 delivered, and even with engrish instructions! Awesome.

The other package was a new Cellman controller, usb tune up cable and a Cycle Analyst. What a well made unit the CA is- well done Justin!



So anyway, I hooked the rejigged mac motor up to the tester, spun her up and..............



Looking good! Phases lights all come on when spun up and the halls all flash. Awesome.

Next step- connect new controller up and spin her. Paul has some concerns at my turning the yoke on the lathe and drilling a few holes in it for cooling- apparently the yokes are carefully balanced at the factory.

I'll spin it and see. If it doesn't vibrate itself to bits, she'll be getting put back together quick smart. Fingers crossed.

[Spicerack]

It lives!!!!!

Thanks for the help Paul- slightly different wiring to the old style throttle I have... but it all appears to work as it should. Even cruise works!

Now to put it all back together...

[stripedtuna]

Thats awesome.

I love this cooking show.. well, "How to un-cook a Mac"..

Great effort mate..

[neptronix]

Very naise

[Spicerack]

Thats awesome.

I love this cooking show.. well, "How to un-cook a Mac"..

Great effort mate..

Yeah- but when I put it all back together and do I really have to use the gerkins?

[stripedtuna]

Is the writing on the controller wrapper to do with the shunt value for the Cycle Analyst??

[Spicerack]

roger that tuna

[Spicerack]

I forgot to take a photo of the cooling holes I did on the yoke. Well when changing the thermo sensor- which required redoing all the wires and then I thought what the heck and drilled a few more cooling holes- I took a photo.

[Quajochem]

Looks really good! I bet that will work well!

[Spicerack]

Hope so. Just been doing a little bit of wiring tidy up and wired up the kill switch on my throttle to be the cruise function, and another separate switch for the variable speed settings (although I guess it will be on "high" 99.9% of the time!).

Ran it on the bench for half an hour on cruise and no problems at all. Better get the side covers modded with cooling holes then chuck it back together.

[fechter]

The cooling holes look good. They could probably be a bit larger without causing structural problems.

How did you get the chips off the magnets? That's always a problem when machining things around magnets.

[fabiograssi]

The cooling holes look good. They could probably be a bit larger without causing structural problems.

How did you get the chips off the magnets? That's always a problem when machining things around magnets.

When this method is possible, I carefully put some paper tape in the magnets, then put some silicon glue over the tape....

[o00scorpion00o]

Will grease not work it's way into the stator ?

And drilling the covers, would that not allow dirt to get into the gears ?

[Spicerack]

I used a fine stainless steel brush followed by my gloved fingers! Did a great job of removing all the swarf and filings.

Shouldn't be a problem with grease getting in there- it tends to stay around the gears. BMC motors have slots in their yokes.

Dust will be kept out by having little bits of filter material on each hole. Small cell foam that used to be the fine dust filter for a vacuum cleaner. Pics to follow when I do it.

[o00scorpion00o]

Watching with great interest!