Refurb of an Old AEI Induction Motor (Pillar Dill)

[Bazz4CQJ]

I’m just starting a refurb of an old pillar drill I’ve acquired. The motor was produced by AEI back in the 60’s (single phase 240V, ¼ HP. Ref D30003 T) see attached. The drill hasn’t been used for some years, so I’m just working towards starting it up. I’ll do a PAT on it before applying mains. It does spin freely and quietly.

I think this a type of motor that has a centrifugal switch on it for a starter winding (it has no capacitor) and the suggestion I’ve seen on Google is that the centrifugal mechanisms can become jammed up from dust and dirt and may respond to a strip down and clean.

I think it may be the case that these motors may not have ball races and should be oiled periodically. I guess that the silver plug shown needs to be removed to allow oiling?

If anyone is familiar with this type of motor and has any suggestion to make, I'd be please to hear them.

Thanks
B

[MotorBikeLes]

I think you just press the nozzle of your oil can into the centre of the oiler cap.

I generally strip and clean these things before use. I have had motors with so much dust that they can track across.
Les.

[mark_in_manc]

This probably makes me a philistine - but I would megger it, and then plug it in briefly. If it spins up, and then runs down, and you hear it 'click' as it is nearly stopped - all is OK. If it doesn't click, the cetrifugal switch may be stuck closed (and leaving it plugged in will make the start windings smoke, and maybe destroy them!). If it doesn't start, the centr. sw. may be stuck open - or someone else may have already melted the start windings

Yes, just a blob of oil pushed through those sprung-loaded cups will work. It probably wasn't oiled much, as it will be vertical on a pillar drill and those types of oilers don't work so well when the motor is not the 'right way up'.

[Bazz4CQJ]

Thanks for the comments. I'm going be working on the mechanical parts, and want to do a decent paint job it when it's finished, so I can easily take the time to dismantle the motor and find out the true state of things.

@mark, when you say megger it, do you mean the windings down to ground? I do have a megger, but was just intending to do "everything in one go" using the PAT machine.

I've always wanted a half-decent "Pillar Dill" (as per title), which should out-perform my cheapy Chinese one, though it is damn heavy!

B

[joebog1]

While you have it in bits Bazz, change the pillar bearings even if they don't "rumble".
I have my pillar drill in bits at the moment myself as I have had a worsening runout on the chuck problem for some time.
The bearings inside the housing felt like brand new, BUT when removed the drive side one was dry.
They are very cheap ( at least here ) and it's a pain to pull it down twice for an $8 bearing.
DO try for a European bearing rather than Asian !!!.

With best wishes

Joe

[ex 2 Base]

If you haven't dismantled a single phase motor before, I suggest you mark each end shield to stator, using a scriber, a pair of scratch marks non drive end and a single the drive end. These marks will help with alignment you when are re assembling the motor. The bolts threads usually are 2BA on an AEI motors. The centrifugal switch is attached to the end shield at the NON drive end, but the operating mechanism is on the rotor.
Be very careful when when moving the end shield around as it is all to easy to break the wires from the switch to the stator winding and its difficult to carry out a satisfactory repair in a confine space. Also, again be very careful when slipping out the rotor, all to easy to catch a stator winding and remove the varnish. You may fine a bush at non drive end and ball bearing at the shaft end. On the better drills/ industrial a taper roller is fitted at the non drive end and ball at the top. Oh, and suck out any dust/fluff aided by a clean paint brush, don't use compressed air as it jams fluff further inside, causing over heating. I hope I have told gramma how to suck eggs. Ted

[Bazz4CQJ]

Don't worry about offending Grandma, Ted! She knows just enough about electric motors to recall that they generally come apart quite easily, but can be really pretty tricky to put back together, and hence this thread seeking advice.

@Joe, yes, I'll definitely be taking a close look at the bearings on the drill and note your comments.

B

[mark_in_manc]

Hi Bazz - yes, I meant megger the insulation from the windings to the frame. I have one particular motor which works great but the frame is live. I only found that out when I got around to earthing the frame

I was surprised recently (with a very noisy motor where I had to replace a ball race at the drive end) to find the bearings were metric - in a British motor from the 70s. But an older drill will probably have English spindle bearings, which sometimes are easy to find, and sometimes are not - the thrust race may be particularly elusive. I'd probably wash them in paraffin and re-pack with grease, but then I'm a tight-ae.

[barrymagrec]

Metric bearings were often used on British motors because, for instance a metric 8mm bore bearing slips easily over a 5/16 shaft to then fit nicely on the slightly raised bearing land. Both Croydon and Fracmo used this technique even before they became the same company.

[mark_in_manc]

That's interesting Barry. I have a few small motor-gearbox units by Croydon, Fracmo, Parvalux etc. Where I work (university lab) these 240v things have largely been swapped out for low-voltage DC units, which I suppose makes sense given the kind of students who operate them!

[Bazz4CQJ]

So, good readings on electrical tests, so I put a few mls of oil in to each port and left it a few days (some internet posts suggest that the oil gets to the bearings via a "wick"). I then decided that it "wasn't bust and didn't need fixing" and not to open it up.

Connected it to my Variac and wound it up to 240V over about 1 second (kinder than a real hard start and but fast enough not to offend the starter winding). I can hear the centrifugal switch drop out nice and cleanly when it's on it's long smooth spin-down. Happy days

B

[mark_in_manc]

There, it works! You'll probably be able to stall 1/4hp drilling 1/2" holes in steel (and perhaps using large hole-saws in thick ply), unless your drill has a back-gear. But for most purposes it'll probably be big enough.

[Bazz4CQJ]

Originally Posted by mark_in_manc

There, it works! You'll probably be able to stall 1/4hp drilling 1/2" holes in steel (and perhaps using large hole-saws in thick ply), unless your drill has a back-gear. But for most purposes it'll probably be big enough.

Yes, 1/4hp is not really that powerful; hopefully this fine product of vintage British engineering may be conservatively rated. I must check what current it is taking. However, the main thing I'm hoping for is a good deal less run-out than my far-eastern Sealey drill; that should not be too hard to achieve .

B

[barrymagrec]

Yes, Ive seen a number of those far Eastern pillar drills - I`ll stick with my Meddings.

[alanworland]

Stick with your stalling motor, it's better than losing an arm!
I have a similar motor and purposely run the belt a tad on the loose side as a safety measure.

Alan

[Bazz4CQJ]

Originally Posted by alanworland

Stick with your stalling motor, it's better than losing an arm!
I have a similar motor and purposely run the belt a tad on the loose side as a safety measure. Alan

Fair point; I do wonder if I am getting accident-prone in my dotage. My Sealey has a motor rated at 1/3hp, and that has generally proved adequate for my hobbyist activities.

B

[Bazz4CQJ]

If anyone wants to see the 70 year old drill I'm refurbishing view http://www.pipemakersforum.com/forum...pic.php?t=4301.

Mine's going be battleship grey (significantly darker) .

B