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View Full Version : Kennametal new tools purchase



Alistair Hosie
02-06-2010, 12:40 PM
HI I just treated myself just before Christmas to a whole new conglomeration of cutting tools/toolholders with indexing cutters I went kinda wild, and so far am really impressed with them I was finding cutting with my old cheapie set a struggle and these are great.It seems there are tungsten and tungsten the oldies were crumbling all the time and cutting poorly.
Anyway the reason I mention it is I wonder if anyone else has tereated themselves to (anything) and would like to hear about it.Alistair

Ken_Shea
02-06-2010, 01:01 PM
Did not buy quality tooling at the first, do now though, however, always as needed only and not in any assortment unless it may be a set, like ER collets etc.

Always the same experience with quality tooling, you never look back.

PixMan
02-06-2010, 04:57 PM
Did not buy quality tooling at the first, do now though, however, always as needed only and not in any assortment unless it may be a set, like ER collets etc.

Always the same experience with quality tooling, you never look back.

Yes, you do look back. With regret. ;)

The latest addition here was a Valenite MVJNR 16-4D holder and a variety of inserts for profiling tasks, and a set of anvils for the lay-down threading insert holder. Next up, a set of the anvils for the internal threading bars.

Ebay can offer some really good bargains if you're patient, diligent, know what you're looking for and know what it's worth (in money spent, time reduced and frustration eliminated.)

Ken_Shea
02-06-2010, 05:01 PM
Yes, you do look back. With regret. ;)
)

I stand corrected :)

cuemaker
02-06-2010, 05:40 PM
Hope I am not stealing the thread with this question, but I feel its sorta inline..

My question is how important is the holder vs. the insert itself?

I am close to purchasing a set to Toolmex (Bison) carbide insert holders, but I am placing Mitsubishi inserts in them on the recommendation of my insert supplier...

I am honestly torn between buying the Toolmex holder which are very reasonable vs a set of Valenite (a bit less than 3x the cost)....

PixMan
02-06-2010, 06:39 PM
The Toolmex holders should be fine. They're made to a fairly high standard. I have a Toolmex (a.k.a. Parfana) 1" S20-MCLNR 4 boring bar and the only thing I'm not impressed by is the quality of the top clamp. I'm hopeful that if it does fail, I can replace it with Valenite hardware.

Go ahead and get the Toolmex holders. However, do buy the Valenite inserts for them if your cutting steels (grades 5615/5625/5635), stainless steels, hardened steels or high temp alloys (grade 9605). From Mitsubishi, I only like their polished inserts for aluminum.

lakeside53
02-06-2010, 08:35 PM
The BEST way to buy holders is when they go on special.... Right now MSC has a deal on Seco MCNLR/L xxxx. $119 includes 14 inserts... basically, the holder is free. I'm getting a left and right hand set next week. I got the MDJNR has week :)


http://www1.mscdirect.com/CGI/NNPDFF?PMCTLG=04&PMPAGE=1

Each month they choose another model.. Be patient and you'll have an entire collection :) Last week they had Hertzel 16-4 holdlers (no inserts) for $69 each. Sign up for their weekly email specials.

cuemaker
02-06-2010, 09:47 PM
Thanks for the replies... I am going with SCLC tool holders that take ccmt 32.5 inserts, including the boring bars (the small ones take the smaller ccmt insert)

Black_Moons
02-06-2010, 10:46 PM
Im not very convinced that high quality holders are much better other then the fact your set screws won't marr the hell out of them as the body is often hardened. Of course, there is a diffrence beween holders that do or don't use the pin and/or clamp. Many of the cheaper holders seem to just use a pin and higher end holders often use pin and clamp.

However, inserts definately vary greatly! Not just in quality but application and grades. for any perticular common holder theres like 20 diffrent inserts you can get for it, beween diffrent coatings, material grade, Material (Carbide, Cermet, ceramic, CBN), thickness (Yes, inserts of the same size come in diffrent thicknesses), Nose radius, relief (Your holder may or may not be able to take diffrently relieved inserts), Coating (3 diffrent coatings are common nowdays afaik), accuracy of the insert (Some are roughly cast +- a few mils, others are ground and polished to tenths). And then likey a few diffrent types of chipbraker, some with additional features like raised cutting edges to provide posative rake, etc.

If it seems overwhelming, thats because it is. you'll have to do some research on what you plan to cut and do some trial and error with feed rates, nose radiuses and SFM.
an insert that does absolute wonders on aluminum might die in seconds if you attempt to cut steel with it.
an insert that cuts steel with a wonderful finish might leave ulgy toolmarks in (some) aluminum alloys, but might still produce a good finish at just the right SFM/feed rate.
Another insert might be able to cut hardened steel at 1000SFM, throwing sparks flying (See: CBN/cermet/ceramic, but $$$$$). No idea what those inserts do to aluminum/steel.

PixMan
02-07-2010, 08:37 AM
Ceramic and CBN inserts shouldn't be used in softer materials because of the edge prep used on them. It's usually a heavy hone because of the brittle nature of the insert material. That doesn't work well on materials that need an upsharp edge to prevent a build-up of work material on the cutting edge. The ceramics and CBN inserts' main feature is wear resistance on superalloys and hardened steels. Ceramics in particular have high hardness and compressive strength to really push high rates, but they don't like interrupted cuts much. ;)

As for holders, it is a good deal when suppliers offer the "kits" of a holder with 10 or 20 inserts. Holders made for negative rake insert geometry can use a variety of clamping systems. The traditional and most common style is the carbide seat with an eccentric cam screw to push the insert into the pocket, and a top clamp to hold it down. A few years back the makers all started producing the type with the seat screwed down with a flat head screw and top clamps that have an integral pin that pull the insert down and back. These use a single Torx or hex key to snug the insert.

Those "quick clamp" style holders are excellent for most applications, but are usually a couple of bucks more money to buy. Where they don't work so good is the very heavy turning jobs, typically those with 5, 6, or 8 size inserts. That pin-type top clamp just isn't quite as secure as the older system when extreme vibration and pressures of truly heavy depth-of-cut and feed rates are employed. That's why you don't see those holders in the big I.C. sizes.

Smaller lathes (usually 13" and under) are better-off with small I.C. screw-down inserts, though cost-per-edge is higher. Those tend to be more upsharp edges and lower cutting pressures. The advantage is that you get to use the same inserts on small-diameter insert boring bars. A smaller inventory of inserts is always easier on the wallet and storage.