# vnmg inserts  use ????



## umahunter (Mar 31, 2017)

What is the best use of these inserts I'm exploring different insert types and there best uses would these be effective on a g0602 10x22 it a 1/2 holder what would be there best use ???? Thanks for any explanation


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## 4GSR (Mar 31, 2017)

They are for light cuts and finishing cuts, .005 to .030" depth of cut with under .010" feed rate.  I have a few that I use just for finish cuts and nothing else.
Ken


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## Bob Korves (Mar 31, 2017)

They are good for tight places.  Next to a tailstock center is a common one.  I don't have any, but I do have the hand ground HSS equivalent...


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## darkzero (Mar 31, 2017)

I agree with Ken & Bob. But keep in mind it's also negative geometry, you may be ok with your lathe but often smaller lathes don't do well with negative geometry. I doubt you would find a holder for VNMG insert in 1/2".

VCMT is the same shape but in positive. That would better suited for hobby lathes. But it only has 2 cutting edges rather than 4 with the VNMG.

35° diamond is too pointy for me, I like 55° (DCMT) better but that's just me.


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## Bamban (Apr 5, 2017)

They make great crowning bit, cutting from the inside out at the spindle speed and feed out by hand.


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## Wreck™Wreck (Apr 9, 2017)

Excellent tool for it's intended purpose. 
As mentioned one may turn very close to a center and also do some limited back cutting, as a general purpose roughing tool they are not ideal, more of a finishing tool.

They will easily produce small undercuts as the work may require.


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## Ulma Doctor (Apr 9, 2017)

i love VNMG on delrin and aluminum
i use them for very light roughing and finish work


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## darkzero (Apr 9, 2017)

Ulma Doctor said:


> i love VNMG on delrin and aluminum
> i use them for very light roughing and finish work



Try VNGG or VNMP, you love them even more on those materials, especially the polished aluminum specific inserts. VNGG have sharper ground edges & VNMP is a higher positive profile.

The only negative insert holders I use are CNMG. I use CNGG inserts & I love them!


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## Wreck™Wreck (Apr 10, 2017)

A near 2 week long job on a machine not intended for this sort of work, 1" 360 brass hex bar, drill, turn and face, thread 15/16"-27 X 9/16" length, bore .781" thru and part off .75" long.

1500 parts.

Quick change tool post and a 3 jaw chuck, five tools per part X 1500 parts, do the math. No bar feeder/puller either so manual chuck/unchuck. Using a VNMG insert for turning, facing and the thread undercut thereby saving a tool change to a grooving tool for this operation, a CNMG insert would not do this. Flood coolant helps keep the chips down where they belong.

This is 1000 Rpm's with the door open and no coolant, at speed the chips will hit you right on the noggin.


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