Kirby D50 commutator/brush seating

[superocd]

How does my commutator look? For the life of me, I can't get it to have a uniform patina. I'm not sure if it will become more uniform as the brushes (which are new) have been given more opportunity to break in through normal use.

Also, one brush seems to have normal, but noticeable arcing while the other does not arc seemingly at all.

On high speed (hose switch depressed), the arcing is more noticeable; also, an orange spark about a quarter inch long seems to jump from this brush periodically (every 15-30 seconds) while on high speed. Unfortunately, I wasn't able to catch it on camera.

On low speed (floor nozzle switch depressed) it does not spark at all, there is only the normal arcing between the commutator and brush.

Will this go away in time?

 

[superocd]

Low speed/floor nozzle brush arc...

 

[superocd]

High speed/hose brush arc...

 

[madman]

I'd say run the motor and break it in some more. New brushes won't seat very quickly. I suppose you could use a commutator stone... never used one myself. The 'patina' doesn't worry me, but that orange arcing does. I bet that brush just needs some more break in time.

 

[superocd]

Oh, I forgot to add, I used a commutator stone

The pic of the commutator is after I have tried and tried to get the patina to wear evenly with the stone, and also to address the brush arc (one brush has an arc but the other doesn't have one that's noticeable).

On the brush with a visible arc, it isn't bad on the nozzle (low) speed, but on hose (high) speed, it is pretty apparent. On high, the arc seems to go from side to side under that brush, almost like how the exposure lamp zips back and forth on a photocopier.

I've run the stone through both speeds, using my shop vac and air compressor in between. I did manage to knock out the periodic orange sparking but that one brush is still arcing while the other is barely perceptible. You might be right, though, it probably needs some time to wear, but every commutator I've seen has some arcing at both brushes.

Realistically, I will probably never use the hose mode, let alone find an original Kirby D50 hose in pristine condition for a decent price, but I want to make this run indefinitely and rule out any potential problem zs I think it would be pretty cool to pass this on in perfect working order to someone who will appreciate it (probably a museum) after I pass away (should have a good 55+ years in me -- I hope -- lol). I'm just thinking ahead because I believe that Kirby vacuums, especially older ones, are like heirlooms.

 

[broomvac]

Looks good to me! Honestly, I’d just stop doing things to it. As MadMan said, the brushes just need to wear in. Sparks happen.

Each time you run the stone over the commutator, you are abrading away just a little bit of (rather precious) commutator copper, something you can never get back. You are change the geometry of the commutator a hair each time you do this, too, and that means that the brushes have a slightly new shape to conform to. All of this is why I don’t recommend resurfacing commutators.

If the motor runs as it should, that’s what counts. Commutators are rarely the point of failure. Frequently, the rest of the vacuum will wear out before the commutator does.

As for your uneven sparking: Sparks happen primarily on the trailing edge of a brush. Is there a chance that this is all you are seeing?

Good luck with everything! Thanks for sharing!

 

[huskyvacs]

The two lads above are right. Commutator stones should only be used very lightly and sparingly, usually once in the lifetime of the vacuum. You don't want to do it all the time as you are actually grinding away the coils on the armature every time you do. Your goal is also not to get all the carbon off, that will never happen, you just want to get it clean enough to where the motor makes a good contact, because too much carbon buildup can block electrical currents and make the motor not run, or run strangely and inaccurately. You also want to give it a few blasts of electrical contact spray after all the polishing to get carbon dust and whatnot out of the armature.

To me that commutator looks just like it would if it left the factory, its very well polished and you did about as good of a job as you could do on a motor that old. The sparks are not bad, and will go away as the brushes wear to the contoured shape of the armature. The fact that it is arcing on one side just means that the motor is leaning more to one side than the other and is closer to that brush than the other side is. Also older vacuums will make sparks, that's normal.

 

[broomvac]

Yep. The only reason to resurface a commutator would be to remove a carbon patina so thick that it noticeably increases the resistance in the motor's circuit. Such a buildup would simply make the motor run noticeably slower than its nominal speed. If the motor runs fine, that means that there is no excessive buildup and therefore no need for a treatment.

Removing the commutator's normal patina is analogous to removing the fine layer of carbon from the inside of your car's exhaust pipe. It's not hurting anything, it won't grow over time, and if you remove it, it'll just come right back. If an unusual amount of carbon ever arises, that's the sign of a problem whose symptoms you are only treating with the commutator stone.

 

[superocd]

That's a "10-4" on the subject of the commutator

Thanks for all your input. I guess I was stressing over nothing, lol.

I will be putting it back together soon and giving it a final polish then!

I wonder what is next in the pipeline for a project. I'm holding out for Classic/Omega or a pre-Sanitronic machine, but I think I better stop for a while. The DS50 makes eight vacuum cleaners now, not including my Rug Doctor X3 or my Shop-Vac. I started this year with just one. My wife thinks I'm crazy, lol. Five of them are hidden away in the closet under the stairs, two are in the closet of my study and the Dual Sanitronic 50 will be out on display in the foyer.

 

[texaskirbyguy]

Break in the new carbon brushes on low speed for a while. After they are broke in, the sparking should be considerably less on high speed.

 

[lesinutah]

Tip

I would have posted earlier but I had to take a few days off.
Before you install armature grab a drill. Put top of the armature shaft in drill. You now can rotate fan out of housing. I use commuter brush and blow off powder.
I seen a pic of arcing. It looked like a green wire was visible. If there are any wires in or around that are it will ruin your vacuum. I hope there is no wire but if there is get it moved.
Les