[PROJECT] Spin Indexer Tailstock

[EdK]

(08-03-2014, 06:21 PM)PixMan Wrote: Noted. What material are you milling with it and what grade of insert do you have in it? Tell me and I'll give you come conservative numbers for cutting speed and feed rate.

Looks like 1018 steel and WKP35 inserts. While the book recommends 820 surface feet per minute, preserve tool life at 500 sfm. That's about 1000 rpm. Feed rate would be .008" per tooth, so .032" per rev or 32 inches per minute. That's cooking! If anything, slow the cutting speed but try to keep the inserts working on feed rate per tooth. Speed kills, not feed (unless excessive.) Don't dip below 350sfm, you'll be hammering the inserts. At a .075" depth of cut you would be pulling about 1.5HP at the spindle, so it'll be working.

Ken,

I'm pretty sure it's 1018. I got it off of ebay years ago. I'll have to check the inserts to see what type they are.

I don't have power feed on the mill yet. That's another project on my long list. Actually it's probably right after this project since I have the power feed and just need to make the mounting brackets. Hmmm, maybe I should tackle that first.

Ed

[EdK]

(08-04-2014, 06:14 AM)Mayhem Wrote: Nice looking shoulder mill there Ed. Is this your maiden voyage with it?
...

Yup, been saving it for a worthy project.

Ed

[PixMan]

Just run it, Ed. Feeding by hand is no problem, just don't baby it. The cutter and inserts can take it.

[EdK]

The inserts are WSP45. I'm going for it. I don't have a tachometer currently hooked up to my mill so I'll just go by feel.

Ed

[EdK]

I thought I'd post pictures of the first pass. It looks worse in the pictures than in real life, at least I think so. The mill was noisier than usual and I don't know if it's from the bearings or the gears. I'll do one more pass on this side and then flip it and mill it to dimension, assuming the mill hangs in there.

I know for an end mill it's advised to cut half the diameter of the end mill in one pass. Does that apply to a tool like I'm using now?

Ed

       

   

[DaveH]

(08-04-2014, 03:36 PM)EdK Wrote: I don't have a tachometer currently hooked up to my mill so I'll just go by feel.

Ed

I'm not sure I understand, doesn't the 'speed selector' say what the spindle speed is ?

DaveH

[DaveH]

(08-04-2014, 03:58 PM)EdK Wrote: I know for an end mill it's advised to cut have the diameter of the end mill in one pass. Does that apply to a tool like I'm using now?

Ed

In a word yes but you could go up to 2/3rd the diameter of the cutter.
And don't forget to mill conventionally - not climb milling

DaveH

[EdK]

(08-04-2014, 04:09 PM)DaveH Wrote:

(08-04-2014, 03:36 PM)EdK Wrote: I don't have a tachometer currently hooked up to my mill so I'll just go by feel.

Ed

I'm not sure I understand, doesn't the 'speed selector' say what the spindle speed is ?

DaveH

No, I installed a VFD shortly after getting the mill. I'm sure one could do the math and figure it out but I'm too lazy.

Ed

[DaveH]

Ed,
Oh I see, now I understand.

DaveH

[PixMan]

(08-04-2014, 04:23 PM)DaveH Wrote:

(08-04-2014, 03:58 PM)EdK Wrote: I know for an end mill it's advised to cut have the diameter of the end mill in one pass. Does that apply to a tool like I'm using now?

Ed

In a word yes but you could go up to 2/3rd the diameter of the cutter.
And don't forget to mill conventionally - not climb milling

DaveH

Dave! I hope you're just joking.

Carbide insert milling cutters should ALWAYS be used climb milling unless impossible to do otherwise. Heavy in, light out. Conventional milling can cause several problems, including higher power requirement, excessive insert wear, chip recutting (and subsequent insert chipping) and more.

I do NOT advise conventional milling approach with that cutter unless the machine has excessive backlash in the screws. If it does, you should still have the entering edge of the cut just past the centerline of the cutter as it traverses the workpiece.

And BTW, that cutter can easily take full width if you want to and have enough power to drive it.

So Ed, how did it work and feel? The chips look like they barely got hot, so your cutting speed is probably low. You want to get the heat out with the chips, not into the workpiece.