Follow rest

[ShawnR]

In preparation for an upcoming project of profiling a long tube, I thought I might practice a bit with a follow rest. Material is just hot rolled steel, about 1.25" diameter. I have tried with HSS and carbide, new insert, different insert, and sharpened the HSS more than once. I am still managing to get chatter. Cuts with HSS have been down around 0.003 to start. I ground the rust/scale off of the piece to keep it off my lathe so now I just want to see what kind of setup and process I need to get an acceptable finish. I don't know what to expect.
The piece is between centers (new technique to me too) Perhaps my centers are not deep enough?

I am hoping for some input/suggestions to try. I did not spend a lot of time yesterday at it, just kinda getting started. I hope to experiment more today. I thought I should get that technique down before I risk damaging that expensive tube I have to turn down.

 

[Brent H]

Only about a month and a half and we get to have some fun!!!

How long is your piece of 1.25? 3 thou on a cut might suggest you need a tweak in the tailstock - dial that in, and then run a light pass. Your “grinding” of the piece may also be causing some issues as it runs against the follow rest bearings.

 

[ShawnR]

Hey Brent!! I am building my list of things to get your personal assistance on!

The piece of stock is about 20 inches long. My follow rest runs on the cut section (behind the cutter, relatively speaking) so I think it should be good, no? I cut a section next to the tailstock until the rest will ride on it. My rest has bearings in it. I am not sure how firmly to adjust those against the stock. Again, messing with different cutters yesterday, I may have caused some issues too. I probably need to work on my bit grinding skills too. I will post some setup photos later. I have not googled follower rests much. I know that all of the popular youtubers have demonstrated it in their videos. It is not usually a stand alone video though so I am guessing it will be a hit and miss to find it.

My 3 thous comment was my depth of cut. I am thinking it is a light cut. At that rate, my project, when I tackle it, will be a very slow one! But after running a few good passes, this will allow me to determine my tail stock alignment. (only to move it later for my project.....) lol

 

[140mower]

Hey Brent!! I am building my list of things to get your personal assistance on!

The piece of stock is about 20 inches long. My follow rest runs on the cut section (behind the cutter, relatively speaking) so I think it should be good, no? I cut a section next to the tailstock until the rest will ride on it. My rest has bearings in it. I am not sure how firmly to adjust those against the stock. Again, messing with different cutters yesterday, I may have caused some issues too. I probably need to work on my bit grinding skills too. I will post some setup photos later. I have not googled follower rests much. I know that all of the popular youtubers have demonstrated it in their videos. It is not usually a stand alone video though so I am guessing it will be a hit and miss to find it.

My 3 thous comment was my depth of cut. I am thinking it is a light cut. At that rate, my project, when I tackle it, will be a very slow one! But after running a few good passes, this will allow me to determine my tail stock alignment. (only to move it later for my project.....) lol

I might have missed a lot, but, if I was looking for 3 thou and surface finish was of paramount importance I would grind a shear tool and take it in 2 or 3 passes.