Craftsman Lathe Motor Size????

[ih1466]

Hi,
I have an old Craftsman 12x36 lathe #101.27440 that has a 1/2 hp. motor on it that is not the original motor. How big of a motor can this lathe take? How big has anybody put on one? I would think a 1hp. would be fine. Is a 1.5hp. too big? I would like to get a bigger lathe, but don't have the money right now.

[1MetalMan]

I've had a number of those Craftsman lathes over the years. They are considered a lite-duty lathe. Most of the gears are made of a type of pot metal and are not very strong. Same goes for the QC (if you have one). I highly recommend you limit the maximum hp to 1/2, or you will end up breaking something for sure!
Regis

[Victor_R]

Hello?

While not totally familiar with your lathe, I think a 1 horse motor would be OK for the low side. Most lathes of this size are sold today with 1&1/2 HP motors. It's also a matter of what will conveniently fit physically, what you will be cutting on it and how much you want to spend. I think much over this is unnecessary. I'd use a 1725 RPM single phase running on 240V.

Check to see what type of frame mount you need (nema 56H or 66 etc.) If your motor is outside (behind) then you will want a totally-enclosed-fan-cooled type (TEFC) to keep from getting chips inside it. If it's below and enclosed, then an open-drip-proof will do and is a little cheaper style frame. You also have a choice of rigid or resilient mounting. Most lathes come with rigid, I think.

I do have a South Bend 9 inch that originally came with a 1/2 horse 3 phase motor. I replaced that with a 3/4 horse single phase (rigid) running at 240V and have never needed more.

Victor

PS: Regis above seems more familiar with it, so I'd go with his advice.

[Matt_Isserstedt]

I've got to agree. The OEM catalog I have from the 50s is not close at hand but I recall 1/3 hp was the low end and 1/2 hp was the top end.

3/4hp would be a honkin' motor. I think the rigidity will give out before you can use even that much hp based on my personal experience.

Now, if you are looking to upgrade, my personal recommendation is for the Clausing 5900 products. 2hp, rigid, 5C capable and hard ways. Instant reversing without the chuck falling off. Real powerfeed (not using the half-nuts). Quick-clamp tailstock. Inserted carbides will sing thru cold rolled steel all day long.

Since I got my Clausing, I just look at the Atlas. The Atlas was a good learner at a price I could afford but a "step up" will make you appreciate a more rigid machine IMHO.

Good luck.

[Jim_King]

Have the same lathe and put a 2hp 3ph motor on it with a vfd.Its like a different machine.I still wouldnt try to hog material off but the variable speed and brake are sweet.It really makes it fun to run.

[jan3]

Regis The pot metal you refer to is Zamac which is formed in a mold under tons of pressure.The material is just one of the Craftsman lathe line ups weak points.I was running a 12" this weekend and was extremely disappointed in the performance.It did not feel much more rigid than my little 6"

[doogdoog]

Aloha, I have a Craftsman 12x36 made by Atlas and the 1hp motor works just fine.

Mahalo,
Howard

[nitearc]

I had a 12" Craftsman lathe that I got with a bad motor, and I used it for a few years with a 3 ph 3/4 hp motor, as that was all I had at the time, and it worked just fine without breaking anything.
Mike

[Bungo]

Anything will work if you are careful, but a big motor can about wrap a Craftsman lathe up ina ball. The 12" looks like a 10" with extensions.

Whatever you want, but I think you can do well with a 1/2 HP.

[gwrdriver]

I have had two Atlas lates, a 10" and a 12", which had 1/2 and 3/4 hp motors respectively and I never wanted for power for the work that I did - large scale (7+ga) steam engines. I agree with the comments on the ability of the Zamak gears to endure much more than 3/4hp but one thing hasn't been mentioned. The 1/2hp motor, if quick reversed, won't entirely spin the chuck off the spindle before you can catch it, meaning stop the motor. But a 3/4 or 1hp would reverse and get back up to speed so quickly you would spin the chuck off before you could stop it.