Hard Milling

[Ron L.]

How about machining hardened steel in a production state instead of tooling (molds die steels etc.)We are quoting parts that are MIM 440ss. (Metal Injection Molding) Then the parts are hardened to 57 58 rc and finished machined. >.001 tol. .02 and .030 dia. mills,Tool Life? 1000 pcs.- Anybody doing production?

[CNCme]

??? Welcome to the forum

 

Im unemployed and I would not want this JOB.

 

 

Try EDM

 

Tony G

Unemployed Programmer

N.E Massachusetts - Sothern New Hamshire

[Brent Wilkerson]

Definitely EDM ram/sinker job. We do wire work .... no sinker here. But you need to machine a graphite electrode and sink the mold.

 

Good luck....

[CPeast]

quote:

---

Im unemployed and I would not want this JOB

---

well said

 

I dont see it happening.

 

We've done a fair amount of hardened 440C(Surface Grinding, Jig Grinding, Wire/Ram EDM and Hard Turning.)

 

I can hardly imagine making a scratch in 58 Rc 440 with a .02" end mill.

 

Any chance of milling in annealed cond. ?

Althogh Im not even sure annealed 440 will make for a very good production milling process with tooling that small.

 

[ 03-18-2003, 09:31 PM: Message edited by: CPeast ]

[fboike]

Ron,

Tooling or production, the same factors apply. speed, feed, amount of stock, vibration.

With the proper tooling and equipment. 58 Rc 440ss can be machined easily. but ther are to many variables to give you an answer.

for .02 and .03 endmills I would think 18000rpm

would be minimum. sorry I couldnt be more help.

[Greg Williams]

Well sorry guys but I think you are all a bit soft,

These moulds would be a great job and I would love to have it.$$$

Milling this would be the best approach, as long as your machines are up to it.

Enough spindle speed

A fast enough controller

A Data server

some good running true rigid toolholders

and you are in business,

 

Check out this mould, it was machined with a .005" ballnose, to better than the tolerance you speak off.

 

http://www.aebishop.com/man_prod.htm

 

Now I am not trying to blow my own trumpet I am just pointing out that anything can be made, It's only a matter of cost! After all that's how man got to the moon.

 

Good Luck

[McRae]

Sandvik is pushing their new Solid Carbide endmills for this type of application. I know that they are hellishly expensive to buy but with the right setup and machine combination - you should be able to mill this successfully. Programming will need to be right - never let the tool leave the surface.

[Ron L.]

We have a deckel maho 30000spindle, I`ve done hard milling, but this jog has a .020 slot that is cast in and needs to be finished. .042 deep.

I`ve test cut with .030 by .04 deep no problem.

I don't have .020s to test with yet!! thanks for the input and I'll let you know.. Ron

[Lucky]

We are cutting various tool steels (S7, H13, D2, M2, 440SS, etc) in the 55-60 Rc range with tools as small as 0.010" dia. We use a Mikron HSM with 42,000 rpm spindle. I believe you can be successfull with your 30k spindle, but I would be running 42k on my machine with tools this small.

 

Try tools from Fraisa USA (fraisa.com) or Jabro Tools available from Tesco in VA. The tool life of the Fraisa tools is superior but the Jabro tools are available in a wider variety of diameters and lengths and the guys at Tesco are great to work with and can provide extensive speed/feed info.

 

Good luck. If you encounter too many problems, I would love a crack at this job. Check out our website.

[TREV]

hello ron,

i have to agree with lucky on this one. i to havecut hardened ss with tools as small as.0078 diameter. we used a boston digital with a 30000 spindle. our cuts were aprox .oo5 deep. as for tooling i'd go with tesco there tolerances are great and hey who else is grinding secondary relief accuratley on a .005 dia. cutter. get the tooling and have at it.

enjoy,

trevor

[CPeast]

Ron,

 

Please let us know how you make out.