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View Full Version : ENCO: Cheap carbide inserts: Opinions?



Doc Nickel
12-16-2004, 03:49 PM
I'd just picked up some new carbide inserts from Airgas when this latest ENCO flyer arrived.

In it they have a listing of several common size inserts for dirt-cheap; basically $20 for a box of 10.

However, they don't have a brand name (just "ENCO") so I'm wondering- are these things worth it? I've never seen a "cheap" insert, or, for that matter, a no-name knockoff insert.

Cheap is fine, but if I never use 'em, or they don't cut well, it's still money wasted.

Has anyone tried these? Or ones similar? Has anyone ever gotten some "cheap" or poorly-made inserts? Do they even make "cheap" inserts?

Doc.

Spin Doctor
12-16-2004, 04:21 PM
What geometery and size. If they are TN's or CN's unless they have a really good chip breaker in the top of the insert they take too much horsepower to run in small lathes. TPG's if they are just the plain insert you had better provide some form of chip breaker otherwise you are gonna get strings. The other thing is the grade. Grade is every thing when it comes to carbide. The wrong grade in the wrong material is a recipe for disastar. Look at the CN series insert in the tool holder below. It provides an effective chip breaker plus it is also a positive rake top edge that performs well in low horsepower machines as long as the surface speed is high enough. Plus the radius is can be a killer as far as performance goes. Larger radii also require more horsepower especially if they are negative rake inserts.
http://img.photobucket.com/albums/v19/markandannie/tool%20holders/MVC-002S.jpg

http://img.photobucket.com/albums/v19/markandannie/tool%20holders/MVC-006S.jpg

[This message has been edited by Spin Doctor (edited 12-16-2004).]

jwaggs
12-16-2004, 04:29 PM
Go to EBAY and search on "carbide inserts". They usually have 5 or 6 pages of inserts listed, brand names in all grades and styles. Sometimes for as little as 50 cents per insert. I have seen cermets and diamond tipped inserts as well (more than 50 cents per).

Doc Nickel
12-16-2004, 04:38 PM
They list a bunch. SPU, TNMG, TPU, SPG, TPG, CNMG, VNMG, some others... all in various IC sizes, coated and uncoated, various grades from C2 to C7.

I'd have to double-check the numbers to see if the ones I'm interested in have the features I need (like chipbreaker) but mainly I was worried about quality.

I mean, I've gotten cheap HSS squares that weren't worth the ninety cents I paid, and I've already gone through the whole rigamarole with buying the $1.98 import 5/16" endmills and so on. Cheap's great, but I make my living at machining, and I've found that there's a limit to cheap.

It'd be really nice to have a boxful of inserts on hand- I only bought two of the threading insert for that new toolpost, and they were $10 each. But again, even at only $20 for a whole box of cheapies, if I can't use the inserts or they don't cut well, it's still money wasted.

Doc.

jmcmullan
12-16-2004, 04:47 PM
I've been using mostly Enco inserts since I got my lathe a few months ago. They actually seem to work about the same as the few expensive inserts I've bought from other suppliers, but I'm probably not using them in a very demanding application. For any given insert type, the geometry is the same. The more expensive ones are shinier which I assume means they have a better surface finish, but I can't tell any difference in the cut they make. For example, the Enco TCMM TiN coated inserts that I use a lot have an chip breaker and finish that looks essentially like that on on SpinDoctor's diamond shaped inserts. This is just a function of the insert type, not the manufacturer.

For me, the insert style has been largely driven by the insert toolholders I've acquired. But, like SpinDoctor say,s the important thing is to get the right grade (and coating) of insert for what type of metal you are machining.

This thread would be a great place for those that are experienced to share some knowledge on what grades they've had good experience with on specific metals - please!

[This message has been edited by jmcmullan (edited 12-16-2004).]

.RC.
12-16-2004, 05:04 PM
When I bought my insert tools with my first lathe they came with cheap chinese inserts. They were nothing but rubbish they chipped and snapped all the time. If I stalled the lathe it broke an insert. If i did an interrupted cut it broke the insert.

I then got some Iscar replacement inserts and have never chipped one of them yet. Even under some horrendous cutting conditions.

Quality inserts work out cheaper in the ling run.

Thrud
12-17-2004, 05:06 AM
Doc

I buy all my inserts if I can on ebay. I have some boring bars that take.160" i.c. triangular inserts and they cost $19 each here - I bought 30 on ebay for $5 total plus shipping.

It is a great way to get state-of-the-art carbide for almost nothing - but you need to learn how to recognise what inserts you need first.

wierdscience
12-17-2004, 07:33 AM
Like Dave says,Ebay and learn your grades/types.Even if you buy new those Kennametal $15 each inserts will outlast 30 of the cheap ones.

suprdvn
12-19-2004, 09:27 AM
Ringer: "...cheap chinese inserts. They were nothing but rubbish they chipped and snapped all the time. If I stalled the lathe it broke an insert. If i did an interrupted cut it broke the insert.
I then got some Iscar replacement inserts and have never chipped one of them yet."

Were the chinese inserts the exact same grade as the Iscar inserts? Sounds to me like they were different grades. If you are getting chipping you need to go to a tougher (softer) grade. If the edges are wearing down then you need a harder insert.

As far as breaking when the spindle stalls, consider yourself lucky if you can pull the insert out without it breaking, regardless of insert quality. On a small manual lathe that may be possible but not on a large lathe or CNC.