I Turned a Lathe On

April 27th, 2009

For Fifty Cents You May Touch my Finger

The boatyard trip did not pan out, so I fiddled with the lathe. It’s actually running.

I know you’re amazed that I installed and programmed a VFD and got the lathe running so fast. I would be amazed, too. If that were true. But it isn’t. The lathe story has more kinks and turns than an Obama campaign promise.

The seller sold me a Clausing 5914. The photo he showed me was actually a 5936. The differences? The 5936 has no clutch, a smaller motor, and no variable speed drive. There is one more difference, which I’ll get to in a minute.

The lathe arrived, and I complained, and this guy insists I got a better lathe than the one I wanted, which may be true, but I spent money on a bigger VFD than I needed (sort of; you’ll understand in a minute), which cost me a lot of money. The seller will not take it back unless I pay shipping. He’s completely wrong on the law, but if this lathe can be made to do what I want, it would be a waste of time and money to take him to court.

I got the VFD out today and started reading the manual. The box had a sticker that said I couldn’t return the VFD if it had been opened. Fine. I had to open it, right? So I started reading up on it, and then I went to look at the lathe’s wiring and motor. I had to find out what size the motor really was; I had been hearing 1 HP and 1 1/2 HP. You need this information to make the VFD work.

I located the motor’s plate, and I removed a panel covering it, and I cleaned the grime off the plate, and lo and behold, it was a 1-phase motor. I am not kidding. You can’t use a VFD with this kind of motor. So instead of spending $125 more for a bigger VFD, I had spent $350 for a VFD I couldn’t use at all. Which is a lot worse.

The seller had offered to send a 2 HP motor for nothing. This was back when I was complaining to him about the small motor. We both thought everything was three-phase at that time. I emailed the seller today and told him to go ahead and ship it. His explanation for the 1-phase motor was that they had replaced the 3-phase job and wired the new 1-phase motor up so it would work with a 3-phase plug and socket. I figured I had a really worn-out lathe, because three-phase motors are very tough, and this lathe had buried one.

I emailed the seller again and suggested I return the lathe and we split the cost of shipping, since it wasn’t much more than what he would have to spend to make this right. He wasn’t having any of that. He claims he received the email after he shipped the motor, but I wouldn’t believe him if he said Barney Frank loved show tunes.

In the midst of all this, I emailed the manufacturer. They got right back to me. Guess what kind of motor this lathe originally shipped with? SINGLE-PHASE. I think you know what that means. This is the original motor. So I got this guy to send me a bigger three-phase motor, on the theory that the old motor had been replaced, when the lathe was actually stock.

Am I going to tell him? Of course not. He promised me a lathe with a 2 HP 3-phase motor, and I am entitled to it. I’ll keep the extra motor and see if I can use it on a mill or a bench grinder or something. Or I’ll sell it. From what I’ve seen so far, I don’t know that this seller would be honest enough to admit that I’m entitled to the motor, so I’m not planning to help him find out it’s not what the lathe came with. For all I know, he’d get on the horn to UPS and beg them to bring it back to him. At this point, if he shipped me a gold Rolex by mistake, I’d sell it, make the deal right, and send him a nice note and the excess money. Minus the price of half a dozen expensive bird toys.

I think the odds that he reads this blog are about like the odds that I’m going to get a refund, so I’m not afraid to say this stuff here.

I tried to measure the runout on the spindle, and if the indicator is right, it’s very low, so I am hoping the lathe isn’t a basket case.

I don’t know where I’m going to get a four-conductor cord or a plug for the new motor, but it looks like I don’t have to worry about that right away.

Okay, I’m stupid. I don’t need a four-conductor cord, do I? The power to the VFD will be single-phase.

I’m turning into a real Fred Sanford/Tim Taylor. When I realized the existing cord was too short, I walked across the garage to the unnecessary forty-foot length of 50-amp 3-conductor cord I bought for my welder, sliced off a piece, put a Home Depot plug on it, and hooked it up. I actually have things like that lying around. Well, I didn’t have the plug. I had a receptacle, for some reason. I had it half wired up before I realized it was a receptacle and had to get in the car. Still, I think I’m pretty amazing. I had my cable cutters and Ideal wire strippers right there at hand. And I bought my first grease gun today.

Please don’t feel inferior.

I can tell I’m going to be a great machinist, because I have already nearly thrown a heavy workpiece across the garage (I dove for cover while the lathe spun down), and I also left the key in the chuck once. I didn’t turn the lathe on, but the sight of the key still in the chuck was enough to put the fear of God in me. And I turned the back gear on without disengaging the direct-drive thing, which didn’t make the drive belt very happy.

Time to eat some Costco chicken.

5 Responses to “I Turned a Lathe On”

  1. jdunmyer Says:

    You may want a 4-conductor cord for between the VFD and the lathe, unless you have the VFD mounted ON the lathe and you can make sure the incoming cord has the ground connected to the lathe’s cabinet.

    Get in the habit of never, ever removing your hand from the chuck key if it’s in the chuck. Never, ever!

    Sure wish you were closer, I’d have given you a grease gun, along with a bunch of other stuff you either need or will need.

  2. greg zywicki Says:

    They make special chuck keys with spring-loaded tips; they’re made so they won’t stay in the chuck. An easy solution to having to remember to check.

  3. og Says:

    If you’re persistent you will find a piece of spring that will fit around the chuck wrench (it’s called a wrench, not a key, for some unknown reason). The spring should fit around the shank reasonably snugly,(while still allowing it to compress) and be strong enough that you have to push a little to get the wrench in. If you let go, it will automatically pop the wrench out of the chuck. Usually onto a toe. And then, again, onto the same toe. Ask Walter to get you a toe, just to save yours from the inevitable pain.

  4. HTRN Says:

    Ah, another 59xx owner!

    A word of advice – there is a delrin bushing that goes on the sliding sleeves that’s a wear item – it’s something like 15 bucks. I STRONGLY suggest you replace it, if it looks remotely worn. What happens when they go to crap, is the belt starts chewing up the epoxy finish on the sliding sheeves. At that point it becomes a very expensive repair(several hundred dollars), or it involves modifications(using a VFD to control the spindle).

  5. HTRN Says:

    Nevermind, I thought you got a 5914, instead of a 5936.

    If the guy is willing to send you a 3 phase motor, I’d go that way – step pulleys combined with a VFD are a much better way to go than varispeed drive of the 5914.