Carbide inserts that don’t need to be ran at crazy high speeds

[kb0thn]

2000 RPM doesn't seem like too much of a show stopper. My CNC lathes can do more than that, but I typically have max RPM set to 2500 just so I can get away with less than optimal work holding. And if you look at the gripping power of the hydraulic chuck, it goes down as RPM increase.

I use CNMG432's for roughers and CNMG431's for finishers. On 304SS I see maybe 6 to 10 minutes life per corner on the rougher. And with the finisher taking 0.010" DOC finishing, I can usually get most of a shift out of a finisher and still hold 0.0002" tolerance on my bearing journals.

 

[Rob F.]

I like Vincent Black Shadows and Ferrari Testa Rossas, too. And the occasional 67 Caddylack Eldorado

"...Now the girls would turn the color of an avocado
When he would drive down the street in his El Dorado..."

 

[EmGo]

"...Now the girls would turn the color of an avocado
When he would drive down the street in his El Dorado..."

What a coincidence ! My eldo was avocado green metallic

But the only ones who watched it were the cops. They were waiting for me to stop and rob a liquor store or something ....

 

[Rob F.]

What a coincidence ! My eldo was avocado green metallic

But the only ones who watched it were the cops. They were waiting for me to stop and rob a liquor store or something ....

Metallic or glitter paint?

 

[EmGo]

Metallic or glitter paint?

However it came from the factory. It was a GM car, we better ask CarbideBob !

Had a red leather interior tho, mmm, pimpin'

One kinda fun thing, you'd pull up to a red light, noses even with some rice burner, and I'd be looking across at their rear wheels Helicopter landing pad in front, dinghy on davits in the rear. Prepared for any eventuality ....

 

[Rob F.]

By glitter paint I mean the kind was typically on boats at the time. BIG flakes. Like kids use in school...
I was imagining you in a green glitter paint caddy with a fur cowboy hat on and collar out to the edge of your shoulders.
Factory metallic kind of subdues my vision

 

[CarbideBob]

My old and trusty SB only runs 1100 RPM max.
It has not seen a HSS bit in over maybe 25 years, all carbide here.
Well not all, some CBN on real hard stuff.

 

[triumph406]

I run whatever's in the toolpost at whatever the rpm is set at, never seen bad insert life with brand name CNMG inserts. Instead of worrying about being at the optimum rpm, depth of cut and feedrate, I just get on with it. Run a manual lathe or Bridgeport long enough you get a feel for what works.

Finishing I use TPGT inserts, name brand inserts (not cheap Chinese ebay knockoffs) small depth of cuts and feedrate for a good finish.

 

[Radar987]

Stop watching Titan. There's nothing "crazy" about the recommend speeds on the carbide inserts you're using. It's normal.

Your machine is slower for safety reasons because it's a toolroom style lathe. If your parts are small, max out the RPM and just make sure your feeds are correct.

If you're getting poor finishes, run your coolant rich. If your machine doesn't have coolant, use cutting oil.

 

[jhov]

I've got a similar lathe and I've had good luck finishing with uncoated cermet inserts in 4140 and aluminum. Don't rough with them though, as they're more fragile than carbide but they give excellent finishes at low SFM.

 

[farmersamm]

I run a little crappy lathe. Maxes out at about 2000rpm.

CCMT inserts (Sandvik) will do a decent job in the UM, and UF, configuration. Has to do with the nose radius. As you move to a smaller radius, the finish improves.

Even in gummy(1018) stuff they'll do an acceptable job at 450rpm-1200rpm. Hit it with some ScotchBrite to knock down the fuzzies, and it's good to go.

If you don't have a ton of rpm to play with............alter your DOC, and feed. Increase depth, and push your feed up. Long as the thing breaks a chip, you'll be in the zone for a somewhat decent finish.

I'm constantly watching the chips as the diameter gets smaller. I change parameters accordingly as the work progresses. Sucks to have a small, or low rpm, machine, but it is what it is.

 

[EmGo]

By glitter paint I mean the kind was typically on boats at the time. BIG flakes. Like kids use in school...

Kinda like this but green ?

I was imagining you in a green glitter paint caddy with a fur cowboy hat on and collar out to the edge of your shoulders.

I could go for that ! But .... reality strikes :

https://files.catbox.moe/zziyls.mp4

 

[Fadriver]

For starters, I’m admittedly not super experienced with cnc machining so take it easy on me. over The past year or so I’ve taught myself how to program the cnc lathe at my job. As you might expect this has been a pretty monumental task but I’ve gotten the hang of it for the most part. One issue I’m running into is tooling. The machine is a fryer et18 lathe and the max spindle speed is ”only” 2000rpm. It seems like most all the inserts I’m finding, if I go off of the speeds and feeds on the packages will want spindle speeds in excess of what this machine can do along with feeds and depth of cuts that Are also likely beyond the ability of this machine. In all honesty, once above about 1500 rpm it Seems kind of sketchy. I use a lot of cnmg inserts but I know I’m burning Them up sooner than I should be by running them outside of what the package says which I assume is their efficiency range. I use mostly sandvik stuff because they have the most useable website in my opinion, but it seems like they only have the newest highest tech high speed machining in mind . The turret takes 3/4” shank holders. I guess my question is, where can I look for inserts that are happy running at lower speeds than the newest industry standard stuff. Work with a2, 4140, and cold roll a lot. Small amounts of aluminum Here and there. It’s a job shop not a production shop. If there’s anything I need to clarify just let me know

Lathe insert market messed-up, expensive need quantity, and you need their boring bars or
stick tools, try Kyocera, kennametal, Iscar also look for their surface speed, on steel you running
like aluminum, if have a small manual lathe do a test, but again i have lathes and go insane once
i see their prices, mills different so many choices, i guess production methods different your guy
next door maybe making endmills, some buy a 50k cnc grinder and bunch of carbide blanks
and do custom endmills, at least i know one man operation, doing endmills

 

[john.k]

I see on a new Chinese site .....set of boring bars plus a box of 10 inserts ..$2.34 ..........toolholder plus box of inserts $2.34 .pretty hard to beat that ...........And also see on the telly finance guru .... new Temu site is going after Bezos.......Chairman Xi really likes the idea of a spy doorbell,too..........It will be called the "Ling" doorbell ......get it ..Ling Ling .

 

[triumph406]

Lathe insert market messed-up, expensive need quantity, and you need their boring bars or
stick tools, try Kyocera, kennametal, Iscar also look for their surface speed, on steel you running
like aluminum, if have a small manual lathe do a test, but again i have lathes and go insane once
i see their prices, mills different so many choices, i guess production methods different your guy
next door maybe making endmills, some buy a 50k cnc grinder and bunch of carbide blanks
and do custom endmills, at least i know one man operation, doing endmills

Nothing messed up about the availability of inserts and holders on ebay. well at least that's been my experience