Probably A Stupid Question About A 4 Jaw Chuck

Tozguy, I don't have a thread on repowering the lathe yet. There are a few factors I'm considering, the most noteworthy is the motor. A neighbor has disassembled cotton gins in our area and has a bunch of electric motors of various sizes that he has basically given me in the past when I needed one for projects. I haven't been able to see what he has, and won't really decide a course of action until meeting with him. Also, a few years back, I bought a motor that was advertised as a Baldor off the internet for a whole hog rotisserie we built. The motor fried itself during the testing stage in the first few minutes of running. I took it to our local electric motor/armature rewind shop and they said it was Chinese junk disguised as a Baldor motor. Needless to say, I am skeptical about buying motors that I haven't seen, or the source.
Another consideration is the oil circulation pump. My Swedish manual says its 110 volt, but I can find no other reference. I'm waiting for an American manual to arrive. I would have thought a wiring schematic was simple enough to translate from Swedish, but I'm not able to, so hopefully when the manual comes in it'll be better explained.
 
Thanks Shiner, wish I could help but when it comes to electrical stuff I am all ears.
Good luck.
 
I've gone the other way putting a smaller 4-jaw in the 3-jaw and thought it was an half-a$$ way of machining but I've recently watched several YouTube videos from the "experts" and see the same thing. IIRC they put some brown paper bag between the jaws of the larger chuck to get a better grip.
30 hp powering your lathe, Holy Cow that's a lot of power :)
 
Pretty common where I come from. Had only one failure that I remember. Power 3 jaw (hydraulic) holding a 4J or a smaller 3J, can't recall. This happened to be a very experienced hand who took chances a lot. He was peering through the sight window, was a little Kia Seiki CNC. It didn't have but about 1/2" length of grip, so when it got near speed, it came out, bounced around and eventually hit the window, which has small steel bars across it. The impact knocked the whole sliding door (some of you know how heavy they are) up off its tracks and it hit him square in the face. Broke his nose and loosened a few teeth.

Yep, it can be done.
 
They always blame it on night shift... Well I have a similar story to Tonys that happen on night shift at a place I worked at in 1999-2000. The machine operator, (I wouldn't call him a machinists because of this accident) chucked up a 15" 3-jaw in a 18" power chuck on a Puma CNC lathe. He took on a job that was for another machine with the proper chuck arrangement. But the power chuck didn't have extended reach jaws of the job, so he put the manual 3-jaw up in the power chuck holding on to about 1/2" length, too. As murphy's law goes, what shouldn't happen did happen the moment the turning tool touch the work. Every piece of sheetmetal on the enclosures has extensive damage, including damage to the ways on the lathe. But it contained the chuck until it settled down into the chip conveyor, messing it up too. Cost of repairs was close to 25K to replace all of the sheet metal and other damaged parts. They took a air grinder and smooth out the damage areas on the ways. I don't think that machine ran right ever again.

So I guess the moral to the story is to make sure you don't get yourself in an accident holding onto a chuck by only 1/2" of griping length. My rule of thumb is if you cannot grip on the full OD of a smaller chuck without turning the jaws around, don't do it!
 
Back in Jr. High School we had to rotate through the shop classes and were shown safety movies (yes, film movies for you younger folks) I still remember bits and pieces of them today. Even the guy two seats up who passed out from the recreation of some accidents.
What I'm trying to get at, is the one where someone started a grinder while standing in front of the machine. As the grinding wheel came up to speed it let loose hitting the operator in the face breaking every bone and turning his face into a bag holding in the fragments.

We were taught to always stand to one side when powering up a machine. Something that I still do today 50+ years later without even thinking about it. The lathe has a clutch so that the spindle can be engaged while well away from the chuck rotation (if you stand in the "right" place).

Anyone else learn to power up machinery while standing away from the direction of rotation?
 
Absolutely.....100% of the time! I saw those movies too. But even handheld tools I "point" them away from me and kind of squint out of habit. Been worth it a time or two.
 
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