Looking for Insert.

[Al_The_Man]

Anyone come across an insert or equivalent TN35/08, I picked up some tooling on ebay and it included an older Face Mill, the guy claims it takes this common insert, I have searched the web and my catalogues and cannot find anything like this number.
There is nothing on the manuf site (Widia).
Anyone heard of it?
Al.

[ALEXCOMO]

I think tn35 is only the quality of the insert(hardness+-)...you can measure the insert and get the standard ISO codification(like APKT1604)

Sorry for my english!

ALEXCOMO

[Mitsui Seiki]

Isn't TN35 the quality of the insert and 08 the radius?
Sandvik and Krupp make inserts with that quality.Like Krupps CCMM 432 TN35 or DNMG 443 TN35.

[Al_The_Man]

Thanks, I will check it out.
Al.

[HuFlungDung]

What shape is the insert?

[Al_The_Man]

The pocket is 60° so I assume triangular?
Al.

[CarbideBob]

TN35 is an old Krupp/Wida grade grade number. (multilayer TiN on C-5 substrate)
This tells you nothing about the insert shape or size.
Any numbers on the cutter body? How about a picture?
Bob

[Al_The_Man]

The edge to the left of the tool pocket shown is horizontal when mounted (perpendicular to the spindle.
It is marked (theta)100 R-7 d2=31.75 H50826 WIDIA M40
Al.

[CarbideBob]

Al,
What you have is a Widax M40 square shoulder cutter.
It was available with three different insert pockets . A 1/2 inch triangle, a 3/8 inch triangle, and a 1/2 inch square.

Looking at your picture I believe that you have the 3/8 triangle pockets. If this is true the opening where the insert sticks out should be somewhere around 0.450 inch and the wedge should clamp a .125 inch thick piece.
The Wida insert for this is a TPK-32 PDR. Also known by it metric name TPKN-1603 PDR.
This is : (T) Triangle, (P) 11 degree positive, (K) precision ground +/-.0005 inch, (3) 3/8 inch inscribed circle, (2) 2/16 inch thick, (PDR) 90 deg right hand corner flat orientation.
Probably not cheap and definitely not standard. (well, standard to Wida but not to anyone else)

However I think you should be able to use a standard TPG-322 (or 323, or 324). The #2 radius will leave a fairly rough finish at medium/high feedrates. A 324 (or even a 326 or 328) will generate better finishes but the larger rads may not stick out of the body far enough.
Metric number would be TPG-16 03 08 (or 16 03 12, or 16 03 16).
My Wida catalogs don't show the clearance angle on the corner flat on the insert and the cutter dwgs don't show the axial rake angle but it appears that there is adequate heel clearance to use a standard 11 degree positive insert.

The nice thing about this style of cutter design was that when you smashed it you could just replace the insert seats without having to buy a new body.
You could also change to a 45 degree lead or round insert by changing the seats.
BTW, I don't know if you are aware of it but Widia is now owned by Kennametal.

Bob

[Al_The_Man]

Thanks alot for the info, as an occasional 'Machinist' I find it quicker to do alot of my own custom stuff for the retrofits I do.
What is the best way of getting a smoother finish with this type of face mill?
Using the recommended feed rates, I always seem to get the circular ridges.
Often slowing down F.R. does not improve that much.
Al.

[HuFlungDung]

The triangular insert is not likely to give a really smooth surface except at an extremely fine feedrate. You could actually check each insert for depth position with an indicator from beneath. You may find that one insert is lower than all the rest. This has the effect of turning the tool into a flycutter, because that insert has the final effect on the finish. You'd have to consider running .005" feed per rev of the cutter, rather than basing the feedrate on feed per tooth.

Having said that, get the largest radius insert that you can, to lessen the scallop effect. If you are looking for a number, I think a 3 digit number like 322, where the last digit is the tip radius in 1/64" excrements Get the largest radius that you can find, but that might only be 324 or something like that.

For best results in facing, you need a face mill with a wiper insert. This is a broader flat that is significantly wide enough to remove scallops from the other inserts, thus a coarse feedrate is possible. I am doubtful that you would find such an insert in a T shape for this tool.

Switching the pockets to take a 1/2" round insert would have a significant effect on improving surface smoothness. Of course, this limits how close you can get to a shoulder.