Cutting 6150 Rc 54-56 with Accupro AlTiN coated end mill

[Thad]

I have a small pocket that needs to be finished after HT. It's only .210 deep and I have to use a 3/16 end mill to get in there. We ordered some AlTiN coated Accupro end mills from MSC for this. I'm finding out that these cutters are junk. I can't find any recommended cutting speeds for these cutters. The pocket was roughed before HT so I only have about .015 stock on the floor and walls. The pocket is .210 deep and .500 X .875. Something this small, I'd think even a crappy end mill would work.

 

As a starting point, I tried 100 SFPM and .002 chip load (S2040/F12) and the cutter was dull before finishing the pocket. The tool isn't chipping, it's wearing. Does anyone have any recommendations for speeds and feeds for this application? I'm thinking I need to lower the RPM or increase the feed.

 

Thad

[Guest]

I typically "only" use Accupro either in pinch or in aluminum

 

If cash is the driving force behind using these cutters, take a look at Garr VRX series, otherwise I'd be looking at Hanita

 

JM2C

[Rotary Ninja]

A big +1 ^^^

 

In our experience here the Garr's are a bit cheaper and perform just as well as the Hanita. But both are kick@$$.

 

If I were to guess, your RPM is going to be closer to 1600 and the feed around 15 IPM. You may even try to run it conventional.

[Guyinthedesert]

+1 with Ninja, lower the rpm and up the feed. Also, on hard stuff like that, you'll get way longer tool life using oil instead of coolant

[Rotary Ninja]

+1 with Ninja, lower the rpm and up the feed. Also, on hard stuff like that, you'll get way longer tool life using oil instead of coolant

 

An old timer showed me that oil trick cutting some hardened stuff on a Bridgeport. It works pretty good.

[Thad]

Looks like I was in the ballpark. It cut much better at 1600 RPM and 12 IPM, though still wore prematurely, in my opinion. I was using an air blast.

 

Cost isn't necessarily the driving force. We just picked something out of the MSC catalog.

 

I think we're going to have the ISCAR rep come in.

 

Thanks for the input guys.

 

Thad

[?Mark]

I used this for all my hard milling up to 65rc (looked like it could handle even harder stuff, but never had a chance to try it)

http://www.niagaracu...emold/mz645.pdf

 

Great finish and tool life (dry cutting only)

 

Another great tool that I setup a library for was Hanita VARIMILL JAVELIN series.

Example: .375 JAVELIN TR4S47 S2649 F24.0 (under 62rc only)

 

Niagara worked better in harder stuff

 

hth

[habigga]

I use OSG Exocarb- WXS cutters for cutting D-2 at 60 and have great tool life.

[Machineguy]

Yea, That ^^^^^.

 

Cuts like butter on 63 RC. Not cheap, but the life span is great and good for finishing.

 

MSC has them.

 

Machieguy

[RayD]

http://www.hitachi-tool.co.jp/j/products/endmill/index_e.html

 

I used to think Hanita was the bomb... Pricey but the MMR/life of these tool's is amazing

 

Had a Production job, keyways in hardend Shafts

Mirus 3x cost of the hanita but:

 

Hainita EM 100-120 Shafts, Mirus 300+ Shafts and cut 1 minute 20 seconds of the cycletime per shaft

 

Cost per part was about equal for the endmill, but saving that time was huge in this case

[Brewster]

http://www.mscdirect.com/global/media/pdf/search/accupro/MSC_Accupro_Catalog_121.pdf?rdrct=accuspe here is a pdf for Accucrap endmills if you are still looking.

[rogkick]

Jabro HSM range. Top notch.

[Thad]

Brewster, thanks for the chart. It will come in handy for general purpose machining.

 

Everyone else, thanks for the suggestions.

[MotorCityMinion]

A few things no one mentioned. Heat shrink holder, Hydraulic chuck, precision collet, that's my preference for holding tools. Get that tool running true. More than a few parts? Use a bull mill, floor first, stay off the walls, hit the walls staying .002 above the floor then finish with the sharp for picking the floor corners. Your process may vary but I typically leave .005 prior to heat treat for finish, depending on the shape of the part.

 

"I use OSG Exocarb- WXS cutters for cutting D-2 at 60 and have great tool life." Same here. Nachi performs just as well. These tools are made with a very thick web and small radial relief. Stub flute length cutters work great in this scenario. One thing to bear in mind with these hard milling end mills and that there is very little relief. The .015 on the floor may create issues.