Annealed 4140

[EdK]

Thanks Ken. I do have the catalog and the page I posted was just an example. You did clear a couple of things up for me. I thought it might be low alloy steel but not so. I found the SFM from the chart for the insert I'll be using and did a .

I'll try to do a video. I've never used my DSLR in video mode but I guess it's time to learn.

Ed

[PixMan]

By the way Ed, from the catalog pages hown, you can see two dots below the icons of a faucet and faucet with a line through it. That means the inserts can be run fine with or without coolant. I generally run steels dry, letting the hot blue chips carry away the heat. The roughing ships should be big and heavy enough to just drop, though a few may hit the chuck and fly.

Which DSLR do you have? I've got an older Nikon D200 that doesn't take videos, and was thinking of upgrading to one that does. The Nikon D600 has my eye!

[EdK]

(01-12-2013, 09:11 PM)PixMan Wrote: By the way Ed, from the catalog pages shown, you can see two dots below the icons of a faucet and faucet with a line through it. That means the inserts can be run fine with or without coolant. I generally run steels dry, letting the hot blue chips carry away the heat. The roughing ships should be big and heavy enough to just drop, though a few may hit the chuck and fly.

Which DSLR do you have? I've got an older Nikon D200 that doesn't take videos, and was thinking of upgrading to one that does. The Nikon D600 has my eye!

I think I'll run dry. Less smoke that way since my shop is in the basement I don't want to risk setting off the smoke detector.

I've got three Canon cameras that will take videos besides stills. The Canon G12 is considered a bridge camera because it's looks like a point and shoot but has a lot of features of a DSLR but you can't swap out lenses. I use that one to take most of my shop related pictures. My Canon T2i was my first DSLR and was one of the higher end consumer DSLRs that Canon sold at the time I bought it. I also have a Canon 7D which is Canon's top of the line crop sensor camera.

I don't know much about Nikon cameras but the D600 looks like a decent camera just looking at the specs. It's a full frame sensor camera while my Canon cameras are crop sensor cameras. You really can't go wrong with either a Nikon or a Canon. The Canon has a slight edge in that there are a lot more lenses available for the them than the Nikons and they are generally a bit cheaper to.

Ed

[bobm4360]

Ed:
If you don't get the finish you want, raise the speed, especially when you get closer to the center of the workpiece. I usually try to make my finish cut at least .010, cuz carbide doesn't do well with light cuts. For example, 3/4" to 1/2", 2 cuts of .050, and finish with .025; 1200-1500 RPM, and feed to give the surface finish you want.
A "Little Mister" or similar coolant setup is about $100, and really lets you work the carbide. Mist coolers can be set up so there is NO smoke or steam, and the workpiece stays cool too!

Regards,
Bob

[PixMan]

The PF4 and PF5 chipbreakers on most of the Walter inserts I sent have a minimum depth of cut of .004" per side, or .008" on diameter. While that light of a dpeth of cut probably wouldn't fly in a stringy material like 1018 cold rolled steel, it'll work well in 4140.

Sometimes it's best to just not use coolant at all. Carbide can be sensitive to thermal shock, resulting in micro cracks at the cutting edge. This kills insert life. Also, coatings such as TiAlN and AlTiN do work better if the coating is allowed to take some heat. Too slow and cool can result in material building up on the edge of the tool. When it builds up too much, the force can cause catastrophic insert failure at worst or a horrible finish at best.

[EdK]

(01-13-2013, 08:39 AM)PixMan Wrote: The PF4 and PF5 chipbreakers on most of the Walter inserts I sent have a minimum depth of cut of .004" per side, or .008" on diameter.

I'm glad you mentioned that. I didn't realize the depth of cut was per side. I think I'll start with about .010 depth of cut, .020 on diameter, and tweak it from there.

Ed

[PixMan]

Those PF4's max out at .157" per side and the PF5's at .197" per side, so don't be afraid to let 'er rip for roughing!

[EdK]

What angle of attack should the insert have to the workpiece, if it matters? Here's the rough angle I usually use.

Thanks,
Ed

   

[PixMan]

That's the right way to do it, Ed. The 80º included angle of the inserts, oriented in that way with the holder, allows you to turn and face without moving the tool.

[EdK]

(01-14-2013, 01:53 PM)PixMan Wrote: That's the right way to do it, Ed. The 80º included angle of the inserts, oriented in that way with the holder, allows you to turn and face without moving the tool.

I kind of figured that's the way to orient it but thought I better ask the expert.

Ed