Trouble getting good finish when turning

Gearhead, I'm betting that the main issue is that your tool is not on center height. This can cause significant finish issues. If the highest you can shim the tool leaves you below center, try shimming the tool post. I am assuming by a turret tool post you mean a 4-way tool post. You can put a 1/4" mild steel plate under the post to raise it and try to center the tool. Bet it will help.
 
Have a look at this page for some info on your lathe, it may help.
http://www.lathes.co.uk/atlas/page4.html
Most of my turning is either stainless or hot rolled steel.
I have found a very sharp HSS bit with proper rake and a rounded tip at slow auto feed (I use my change gears and swap the 120 gear with the small one on the lead screw on my 9x20) gives very good results.
Another way is to use a shearing bit as a final finish to size.
Some awesome info on bit sharpening
http://conradhoffman.com/advancedsharp.htm
 
I would like to see a pic of your cutting tool. I think you might need a bit of top rake.
Jimsehr
 
the cheapo hot rolled steel from hardware stores, no idea what grade.
Its sticky/gummy and turns just like the original poster says he's having trouble with but slow and sharp with cutting fluid works for me.
I hone the edge to do the final bit of sharpening.
The first initial cut to get through the top layer of scale and other crud leaves a lot to be desired but after this its ok.
This was a chunk of rusty 16mm hot rolled steel turned down to 14.7 with no attention paid to get it smooth, I just needed the sizes/diameters
To the fingers it feels smooth.
25x100-8.jpg
 
All other things considered I wonder if his motor is firmly mounted, what type of belts, etc...? Before I got my Grizzly G4003G I read about many experienced guys not happy with the finishes they were getting with their G4003G. It turned out to be how the motor is mounted. Isolating the motor as best as possible by switching to sandwich type rubber mounts for the motor makes all the difference. The ones I got were these from McMaster-Carr. Also switching over to the link type belts also made a positive difference.
 
Cool! Answers to questions I could not put into words. Most excellent Sirs!!!!!!
 
I don't think feed rate is you problem.

It is hard to imagine even the junkiest lathe having a feed rate that is too fast for getting a finish better than described.
I think you have two (or maybe 3) issues going on.
I suspect your tool is too low. A ridged finish is exactly what you get when a tool is too low. The ridges are made worse when the set is not rigid enough (that is your possible 3rd problem). unsupported work, the tool post not well seated, too much stick out on the tool all contribute to a ridged finished - it occurs when the work bends up or the tool flexes down causing a slightly larger diameter. When it snaps back into position, the tool grabs and pulls the work deeper causing a smaller diameter.
I think your other issue is tool profile. Smearing is exactly what you get when the tool profile is wrong. Smearing come from the chips getting trapped between the cutter and the work, materials like aluminum are especially prone to it. The solution is more front clearance and proper cutting oil (light cutting oil for ferrous metals, WD40 for Al).

A pic of the tool, the tool set up, and the finish would be helpful.
For what it is worth, I often make finish cuts on steel with a tool that has almost no radius and they come out mirror smooth. Radius is important, but it is not the final answer.
 
I believe the slowest feed rate on the atlas craftsman is .0042per rev. But I still get good finish at that.
 
Learning to machine on questionable stock is stacking the odds against yourself. I would seriously suggest getting some 12L14 to learn on , it is not expensive and it will reward you if your tool is sharpened correctly and set on height.
 
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