The ultimate novice question...

ScrapMetal

ScrapMetal

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Okay, that me be a bit of a stretch, or not, but here goes:

Now that I have my 11" SB lathe set up, leveled, and misc. oils ordered and on the way, I need some suggestions for what to do with it to get a feel for using it. I've read "How to use a Lathe" but I'm not real sure on what I should be doing to start the "hands on" learning curve here. :-\ Learning to whittle you take a stick and use your knife to make a pointy stick, where to start on the lathe? :)

-Ron
 
Well, I'd say that the majority of operations on the lathe involve simple, straightforward metal removal by turning. Sketch up a simple shaft with at least 4 diameters, and a length of 1.0000" on each step. Make the diameters about 0.2500 different, larger towards the chuck. So, using those figures, you'll need a piece of round at least 5" long. In a three jaw, chuck up on it with just about 1/2" sticking out, and face it, cutting from the outside in. Take note of the teat in the center as a guide for tool height. On center, there will be very little. After facing, center drill to about 80% of the body diameter of the center drill. Chuck the piece on about 3/4" and use the tailstock to support the end. If this is a piece of rough stock, you will want to chuck up short on it, and turn true a length to chuck for the first operation, the face and center drill. You will need to pick a good speed for the spindle, and good feeds. If you'll let us know the diameter and material type of possible, we can give you spindle speed range.
 
I would have you start by running the features of the lathe like power feeds ect. to get used to it before putting metal in it. Start out cutting with a soft metal like aluminum, it cuts easy. Take shallow cuts at first to get a feel for cutting, and take your time. Reading a book and doing is a lot different. If it does not cut right and smooth check to see why before proceeding. There is a lot to learn before it comes second nature and a lot can go wrong with missing one step on setup, like tighten chuck, leaving key in chuck, cutter not being on center ect., so double check everything before turning on machine twice. As you can tell I am for safety. Just my $0.02 worth for a beginner.
Paul
 
Pick out some simple steam engine, maybe a one cylinder wiggler, and just do it. No better way to learn. And you have something when your done. There are many primitive models to choose from.
 
The best project is the one you are doing right now. Pick a subject and get started, then as you run into issues you can learn to work around and solve them. It's the most rewarding part when you take something that you made out of the chuck and set it on your desk to admire. Especially since you will know how imperfect it really is, but the rest of the world will be truly amazed. Keep the secret of how messed up it really is to yourself and smile when they tell you how neat it is. Nothing more fun or more interesting than getting you mess ups straightened out and well hidden. Truly makes all of the other stuff worth the hassle.
Bob
 
Go HERE and look at the Projects, Prints & More section. You're not the first to ask this question!
 
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A lot of great replies here guys, thanks. Gives me a lot to consider.

David, SB's "Machine Shop Projects" is one of the books that I have. It has actually forced me onto another "learning curve" where I am trying to figure out the modern equivalents of things like "machinery steel" and which steel to use when it calls for "cold rolled steel" or "cold drawn steel". The steel selection alone is kind of bewildering especially for one just getting their feet wet in machining.

As another example of my ignorance knowing no bounds, here's another little question that has me "concerned". Say that you are doing a cut on the lathe (or cutting threads for that matter), assuming that you will always be using the power feed (May need to clue me in here. :P), how do you stop the cut at a certain point? To phrase in a couple different ways: You are doing a cut to a "shoulder", how do you stop it without cutting in to that shoulder? With threads, how do you "lift" the bit off at the same point so as not to have any cuts after a certain point? I've read the "How to.." book a number of times and that nice little detail still eludes me. Yes, I do feel like a complete idiot, thank you very much. ;D

-Ron
 
even with a shoulder i like to do a small undercut area then hand turn the spindle to cut to the end of the threads thats just my way of doing it ;D

there is a good first project build a spindle crank handle!

as you get used to operating the lathe you will find your comfort zone pretty fast

Blame
 
If you need a specific dimension held, like in the step turning project, use a dial indicator mounted to measure the travel. I have a MightyMag with a 2" travel dial indicator on it for that. For feeding into a shoulder, disengage the feed a bit short of the shoulder, and hand feed until you get to the "0" you have set. If your tool is set properly for turning to a shoulder, it will have a slight (<1 deg) negative lead, and you should feed out to square the shoulder cut. Some folks turn a little short of the shoulder, and a little shorter each pass until the finish pass, then face in at Z minus 0.0020, then take the final pass and feed out on the finished dimensions,

Use of a dial indicator presumes you have no DRO (Digital Read Out) on the machine. I like to see people learn the basics without one, then appreciate the luxury when they get one.

For threading, I don't use a DRO for the Z positioning. I set an indicator so that there is 0.5000" travel from the first touch of the stem contact and the final stopping place. I watch the dial and count the revolutions to get the rhythm and as the "0's" go past......1,2,3,4, STOP! and pull the tool out of the cut right at that point. Usually can hit the point within a couple of thousandths, unless it is a coarse thread. I can't seem to get the same rhythm effect from the DRO, so the dial works good for me.
 
I think I get the concept. It's striking me that a lot of what I need to do is to (very carefully) just get some hands-on time with the lathe getting the feel of it. Kind of like driving a car, you can read the manual but there's no teacher like getting behind the wheel.

Thanks much guys, you are helping more than you know.

-Ron
 
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