1st chips, no blood

I do not grind stock like this as I dislike hand grinding in every possible way. I just throw inserts at them, I am on the clock and have to make time which does not allow handwork and insert changes only take minutes at worst.
I also do not have to pay for them(-:
 
Very interesting stuff, most of the tech part went right over my head. Whats burn outs, I know what they are in an autombile:eek:
 
Creativechipper said:
Very interesting stuff, most of the tech part went right over my head. Whats burn outs, I know what they are in an autombile:eek:
Click to expand...

A burn out as referenced here is a part that is cut with a torch.
 
Creativechipper said:
That is quite a hefty turn job, whats it for?

I do have some steel rod about .25" diameter. It may be hardened, I do not know, it started life as a shaft in a copy finisher.

I turned the 1st 2 cuts at about 750RPM, any advice on RPM's
Click to expand...

The basic rule is: Cutting speed x4 /diameter
Cutting speed is expressed in Surface Feet per Minute and is different for different materials and whether the cutting tool is HSS or carbide.

https://littlemachineshop.com/reference/cuttingspeeds.php

You will find cutting speeds vary wildly from one chart to another. I was taught to use 80-100 SFM for HSS cutter in 1018 steel.
I'm always conservative to prolong tool life, so I use 80 SFM

80x4/.25=1200 rpm.

That .25 dia. shaft is probably hardened. Are you using carbide or HSS?
 
I have HSS and carbide, my HSS tooling is 1/2" and my carbide indexable tools are 1/4"

I have been using anywhere from 800-950 rpm with the hss and I tried a carbide cutter last night at 800rpm.

My cuts are looking 300% better, I am getting smoother at rolling the wheel to the cross feed and using different cutters.

I am having a blast, taking my time setting tool heights, locking the carriage down and the lead screw clamped/locked to carriage, zeroing my dials to my work and setting a cut depth. Trying to get good work methods and a nice routine to double check everything, safety glasses by the start switch..lol

Any methods procedures or good habits to lathe use,please share.

Many thanks to you all for helping me through the frustrating parts of starting to use a lathe!!
 
Creativechipper said:
I have HSS and carbide, my HSS tooling is 1/2" and my carbide indexable tools are 1/4"

I have been using anywhere from 800-950 rpm with the hss and I tried a carbide cutter last night at 800rpm.

My cuts are looking 300% better, I am getting smoother at rolling the wheel to the cross feed and using different cutters.

I am having a blast, taking my time setting tool heights, locking the carriage down and the lead screw clamped/locked to carriage, zeroing my dials to my work and setting a cut depth. Trying to get good work methods and a nice routine to double check everything, safety glasses by the start switch..lol

Any methods procedures or good habits to lathe use,please share.

Many thanks to you all for helping me through the frustrating parts of starting to use a lathe!!
Click to expand...

The size of the cutter is only important for calculating speed on a mill. On a lathe, it's the size of the stock you are turning. You are calculating Spindle Speed, regardless of whether it's the tool or the stock that is rotating. Rule of thumb for carbide is 2-10x faster than HSS. That's a broad range, but there are lots of variables. If HSS held up at 800-950, you can safely double that for carbide. Also, on a facing cut, the diameter gets smaller as you face in. CNC machines will automatically increase rpm as the cut proceeds towards the center.

I was in Placerville last week. My former boss now lives there. He is liquidating a bunch of stuff and gave me a 12x18 granite surface plate and a box full of end mills and other things. If you see any CL adds for tools in Volcano, it's him.
 
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Thanks for the heads up, will check CL, as a newbie I need stuff for sure.

Like a set of center punches measuring squares, live center, 4 jaw chuck, the list goes on and on, tap and threading stuff..lol

So it sounds like carbide cutters want speed, my low end goes up to 1000, but I only see 950 on my rpm dial, should I switch to the hi setting for carbide?
 
1/4" round in a lathe using carbide tooling at a conservative cut speed of 200 FPM and a speed of 3000 Rpms is a good start.
If HSS tooling try 60 SFM, this will be 900 Rpms.
 
How about length of round stock for a face cut, how much material sticking out the back of the lathe can I get away with before needing a spider or support?

I have a 1/2" steel bar, slightly bent, that sticks out the back about 4". I dont think any more of a wobble or length would be good.
I chucked it up and did some face cuts being careful to turn up my RPM's a lil at a time.

Seems ok but you all have the experience,what do you use as a guideline?

thanks
 
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