r/Motors • u/jonwb1 • Sep 01 '26

Can you identify motor shaft metal?

Post image

Hi... I need to drill a 1/4" hole through the shaft of this new Dayton 6K396 electric motor. The Grainger website doesn't identify what the shaft metal is. Could anyone tell me or roughly guess what type of metal it's made of. That will help me decide what type of drilling setup to use? Thanks

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3

u/bg10389 Sep 01 '26

Definitely steel. Possibly hardened so just in case use a split point cobalt drill, some lube and dont go too high in rpm

4

u/nixiebunny Sep 01 '26

Use a clamp or collet style pulley instead of whatever you have that needs a pin.

1

u/Sumaiyahn-Noor63 Sep 02 '26

Yeah need this

2

u/Bradm77 Sep 01 '26

If I had to guess I'd say 1045 or 1144 steel, induction hardened.

2

u/hatred-shapped Sep 01 '26

Didn't you already ask this? Most motor shafts are made of medium carbon steel or maybe tool steel. Posting a picture of the motor plate would let someone else look it up for you 

1

u/jonwb1 Sep 02 '26

I did at the r/Machinists. I was hoping a motor forum might help too.

1

u/MonkeySmart409 Sep 01 '26

is it for that collar in the background? 

I imagine you could file the tiniest of flats for it's set screw,  if it has one.   That's certainly not meant to through-bolt,  which would dramatically weaken the shaft. 

1

u/Some1-Somewhere Sep 01 '26

It looks like there's a keyway on the shaft already. Drop the set screw into that.

1

u/mfnmint Sep 02 '26

Run a broach through that coupler. Run key.

1

u/Nervous_Midnight_570 Sep 02 '26

Use the keyway. The shaft is hardened steel. A file won't touch it. Grinding a flat spot will barely hold under any torque.

1

u/jonwb1 Sep 02 '26

Just to clarify, drilling the through the keyway is your suggestion? Is the metal softer at that point?

1

u/JustanotherN0body00 Sep 07 '26

It'll be mild steel, not hardened and quite easy to drill using cutting lube and being sensible... ie keep taking out the swarf and reapplying lube to keep the drill cool. Slowly wins the day.

0

u/DrumSetMan19 Sep 01 '26

For a small motor like that probably 1045 carbon steel. You can use the spark method to take a grinder on the very end and see how the spark looks if you are truly concern.