Speeds and feeds for inserts are centered more around production machines and high Hp, as opposed to smaller lathes. I usually run my lathe speeds/feeds at about 1/4-1/2 of what is printed on the insert boxes. Feeds are predominately around 0.004"/rev, with a range of 0.007-0.002"/rev. The DOC is often determined by the insert nose diameter and also if the insert is molded (CCMT) vs ground (CCGT), the latter being much sharper and able to take finer cuts without the nose of the insert deflecting from the work. I typically use a 32.51 insert size, so typically the minimum DOC is around 0.002, the maximum cut on the 1340GT is in the range of 0.1-0.15 diameter with a feed in the 0.004-5" range. I rarely use a 32.52 insert, dut it requires a slightly deeper cut probably on the order of 0.004-0.006", and give a very nice finish. A CGGT type can take a smaller depth cut, but I would get these inserts on different materials to get a feel of DOC and feed for your machine. Aluminum you can push faster speeds. The brand/quality of the insert can make a significant difference in how well they work. My go to insert for all steel (they will also work ok in aluminum) is an Iscar ISCAR CCMT 32.51 or 3-2-SM IC907 CCMT09T308-SM
https://www.ebay.com/itm/10-pcs-ISCAR-CCMT-3-2-SM-IC907-CCMT09T308-SM/323271443088
On 3/4" stock I am running the RPM in the 600-800 RPM range for O1 steel, aluminum you can turn faster but I get a clean cut also at this RPM. On steel you can look at the chips to see the color (straw color, then turning blue after they come off) to see if you are pushing too hard. Higher feed rates will help break the chips into C's as opposed to long strings, but sometimes the machine does not have the ultimate power and rigidity to remove high volumes of materials. Every material turns differently and will show a remarkable difference in finish based on speed and feed, I found with steel I needed to increase my feed rate to around 0.004-0.005"/rev gave a much better finish then slower feeds. When targeting a final dimension, as I get closer to the target dimension I will take something like one or two 0.01" passes and look at my DRO reading and measure the actual cut diameters to compare the two. Then adjust the last pass to compensate for the difference. Typically I can hit 0.0005" dimensional accuracy.
If you are pushing too hard on turning or drilling you will get some chatter or singing, so that is the nice feature of the VFD that you can adjust the speed on the fly. I find this is a significant factor when drilling and boring, so my MT3 drills, something like a 3/4" will be happiest at around 250 RPM, a 1/2 drill around 400-500 RPM, 1/4" around 800 RPM into steel with some lube and periodically clearing the chips.
Below are some chuck keys for the Bison I made a long time ago, I cut the square using a collet block on the mill and used a file to tweak the final fit. I relieved the back end to decrease the weight and added a small set screw that holds the T handle in place. I use a small magnetic in the tip of each key so they don not fall out when rotating the chuck. I set up a 0.0001" reading dial indicator in a QCTP holder which makes for very quick work of dialing down the TIR. I like the Starrett 25-511 or 25-611 series dial indicators because of the range (0.2") and resolution (0.0001"), sometimes they come up in good used condition for around $80 or new for a bit more. There are some inexpensive imports as an alternative, but I use one dial indicator and one test indicator for pretty much everything, it was worth buying once. When checking the TIR on the lathe I often use the JOG function for final reading, turning by hand can introduce more variation when turning the chuck.
https://www.ebay.com/itm/Brown-Shar...001-0-5-0-Rotating-Dial-Lug-Back/162914577775
https://www.ebay.com/itm/Starrett-25-611J-Dial-Indicator/292554013714
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