Learning to work withing the limits of my lathe (and myself)

[papa-roe]

In January I began lathe (and welding) training at the local tech school. Shortly after I started, I was in an auto accident and hurt my back. I ended up dropping out completely. But not before getting the drawings for my first project. It is a simple project turning a piece of 1" round stock to 5 different diameters along it's length. It includes a facing operation, center drilling for a live center, turning and parting off. I finally felt well enough to try this on my 61 year old Clausing 6913. In class I would have been turning 12L14. At home I have some 1" A36 round stock left over from an axle I made for my nephews wagon so that is what I am using. I learned from trial and error how to set the feed rate (it does not operate smoothly), that the recommended spindle speed needs to be doubled when using carbide inserts, my cross feed has a lot of back lash, that close is not close enough when centering the lathe tool. Indicating A36 round stock with mill scale and general out of round is difficult. All I could do is get it close and trust that I could turn it the rest of the way. My first piece was pretty much just getting on the same page with my lathe and figuring out that just because the levers move, does not mean that the inner workings are going to mesh like they're supposed to. I started my second attempt this evening and my first diameter came out .003 under size (I should have let it cool down after my rough cuts). I flipped it around and indicated off of what I already turned and then faced it off. Tomorrow, I will be center drilling the end to accept my dead center. I would prefer a live center but I gotta use what I got. Then I will turn the rest of the diameters. I have lots of round stock so I can do it again and again until I feel comfortable with the different operations. I am pretty excited.

 

[Boswell]

I have lots of round stock so I can do it again and again until I feel comfortable with the different operations. I am pretty excited.

I remember when I got my lathe and started to experiment on how to make things. Watched a lot of YouTube videos, made a lot of chips and after a while got pretty comfortable with things. It was a major celebration when I make my first internal an external single point threads. Just trying to say don't get discouraged and keep practicing.

 

[Mystery1]

Learning by doing, a timeless approach And it is as rewarding as ever.

 

[vocatexas]

It's fun, ain't it? Keep practicing! I'm still new to all this, but when I first got my benchtop lathe, I turned several pounds of shaft into chips. Similar to your project, I would set myself targets to hit and make metal disappear until I got it right.

 

[Aukai]

Thank you for the drawing, something I can practice when I get my lathe squared.

 

[T Bredehoft]

Don't be afraid to make errors, they happen no matter how much experience you have.
With a dead center you must be concerned with lubrication of the point and RPM of the part. My original training included putting white lead (putty) in the center hole for the dead center. it is an excellent lubricant but will self destruct if over heated. In other words, don't run at carbide speed, probably try to run as slow and you can stand.

 

[papa-roe]

Don't be afraid to make errors, they happen no matter how much experience you have.
With a dead center you must be concerned with lubrication of the point and RPM of the part. My original training included putting white lead (putty) in the center hole for the dead center. it is an excellent lubricant but will self destruct if over heated. In other words, don't run at carbide speed, probably try to run as slow and you can stand.

I believe that I am going to buy a live center before I finish this. The dead center needs to be dressed anyway. I can get a cheap one until I get the funds for a better one.

 

[rock_breaker]

No doubt someone will beat me to the post but you can dress up a soft dead center with your lathe's cross feed set at a 30/60 degree angle. It will be hand feeding and should be done slowly with a sharp bit for a better finish. And like has been said about white lead the same can be said for oil but backing the dead center off, occasionally adding oil and resetting doesn't take much time.
Have a good day
Ray

 

[dewbane]

I can get a cheap one until I get the funds for a better one.

I'm pretty impressed with the $30 "medium duty" live center I picked up last time I ordered from Little Machine Shop. I had low expectations, and would have settled for less than I got.

 

[Ray C]

I'm pretty impressed with the $30 "medium duty" live center I picked up last time I ordered from Little Machine Shop. I had low expectations, and would have settled for less than I got.

For homeshop/hobby use where the typical piece of stock weighs under 20 pounds, there's absolutely nothing wrong with using a "medium duty" live center. Medium duty live centers usually have a smaller body which is helpful with tight setups. Load capacity for MT2 will be in the ballpark range of 200 to 300lbs. In this day and age, any modern production unit will have excellent runout specs. I have a couple medium MT3's and actually prefer them because of their reduced size and I've never had a problem holding specs with them.

Ray