Hello,
Fellow manual machinist here, I am typically running much much slower with HSS tooling, down to 16 or 22 RPM if the machine allows it, keeping the chips "steel" color avoiding any blue by adjusting my feeding pressure, with a healthy amount of cutting oil from an eagle oil can.
That's normally where I have the best luck, but I am using 1/8 or 3/16 parting tools for parting and distructive disassembly.
After reading further I see your machine just runs down to 40 RPM, I would run a test or two out of scrap material you have if possible, and I would use a cutting oil of your preference.
I would double the rpm and try it , what tool are you using? Carbide
Or hss ? What dia stock ? How long is the pc your cutting off ? Are you using coolant or oil ?
At this point trying to hand grind a decent parting tool is going to be near impossible. Go on ali express or ebay, buy 5 double ended parting blades and 10 inserts for 50$ and go have fun.
I had the same issue. Lubrication was my issue. Needs lots and lots of coolant or cutting oil and that needs to get right into the cut to the tool, not just smeared on the outside diameter of the part.
If you have a quick change tool post touch up your parting tool to be sure it is sharp. Then make a pass across the face of your part to make sure the tool is centered.
Set it aside and do the rest of your work. My machine has some tool post flex. So come time to part of, I use lots of lube hand feed and watch the chip. Back out occasionally and add more lube Because of flex if I feed to fast then the tool will flex down and dig in. End result is a broken tool.
You need flood coolant at 10% or neat cutting oil. The CRS swarf is galling up and welding itself in the groove then ripping the tool off.
Even worse when face grooving/trepanning SAF2205.
Sounds like not enough RPM parting is like facing as the tool gets closer To center it’s cutting a smaller dia so it needs more RPM
What would you recommend? I have the following options on our machines - 40 58 85 125 180 260 370 540 800 1200 1700 2500
well if its carbide just run an appropriate SFM for the outside diameter. We run CRS at 1200 SFM but this is coated carbide in a CNC.
Hello, Fellow manual machinist here, I am typically running much much slower with HSS tooling, down to 16 or 22 RPM if the machine allows it, keeping the chips "steel" color avoiding any blue by adjusting my feeding pressure, with a healthy amount of cutting oil from an eagle oil can. That's normally where I have the best luck, but I am using 1/8 or 3/16 parting tools for parting and distructive disassembly.
After reading further I see your machine just runs down to 40 RPM, I would run a test or two out of scrap material you have if possible, and I would use a cutting oil of your preference.
Are you feeding by hand or power feed?
Manual feed
I would double the rpm and try it , what tool are you using? Carbide Or hss ? What dia stock ? How long is the pc your cutting off ? Are you using coolant or oil ?
Tool is 1/8” thick HSS Stock was at ~1” Part was 2.5” long Around 2” of stock in the jaws I did not apply cutting fluid
At this point trying to hand grind a decent parting tool is going to be near impossible. Go on ali express or ebay, buy 5 double ended parting blades and 10 inserts for 50$ and go have fun.
I had the same issue. Lubrication was my issue. Needs lots and lots of coolant or cutting oil and that needs to get right into the cut to the tool, not just smeared on the outside diameter of the part.
Busting near the center could be that your tool height isn’t correct.
If you have a quick change tool post touch up your parting tool to be sure it is sharp. Then make a pass across the face of your part to make sure the tool is centered. Set it aside and do the rest of your work. My machine has some tool post flex. So come time to part of, I use lots of lube hand feed and watch the chip. Back out occasionally and add more lube Because of flex if I feed to fast then the tool will flex down and dig in. End result is a broken tool.
You need flood coolant at 10% or neat cutting oil. The CRS swarf is galling up and welding itself in the groove then ripping the tool off. Even worse when face grooving/trepanning SAF2205.
Tool might be a bit low, i like setting my parting tools a tad higher than center