Milling Large knurls

[Roger]

Any one here mill diamond knurls using the rotary? This parts finished diameter is 1.3" x 7" long. If so, what was the angle of your tool? (45 degrees?), or ???

[jeff]

Any one here mill diamond knurls using the rotary? This parts finished diameter is 1.3" x 7" long. If so, what was the angle of your tool? (45 degrees?), or ???

Never tried it, but that's a nice lookin knurl right there!

[crazy^millman]

Yes and I like using a saw type of cutter verse an endmill style cutter. Something like this: http://www.harveytool.com/prod/Double-Angle-Shank-Cutters/Specialty-Profiles/Browse-Our-Products_196/Double-Angle-Shank-Cutters---Pointed_210.aspx

 

You get aware from Zero Surface speed at the tip which will give a poor finish. Using a tool like above you get get tool life and better looking parts.

 

Far as the angle goes really comes down to what you are looking to achieve. Remember this will be a 4 Axis toolpath not a simple 3 + 1 toolpath to machine the knurl you have shown there. That has an impact on what angle you will use.

 

HTH

[AMCNitro]

Yes and I like using a saw type of cutter verse an endmill style cutter. Something like this: http://www.harveytool.com/prod/Double-Angle-Shank-Cutters/Specialty-Profiles/Browse-Our-Products_196/Double-Angle-Shank-Cutters---Pointed_210.aspx

 

You get aware from Zero Surface speed at the tip which will give a poor finish. Using a tool like above you get get tool life and better looking parts.

 

Far as the angle goes really comes down to what you are looking to achieve. Remember this will be a 4 Axis toolpath not a simple 3 + 1 toolpath to machine the knurl you have shown there. That has an impact on what angle you will use.

 

HTH

So, you're spinning the rotary as you advance the tool?  Its never crossed my my mind about doing a knurl on the mill, interesting.  

[Roger]

Ron, I understand, and like your tool suggestion, but I was planning on doing this using full rotary motion on a 3 axis vertical, and I don't see how your tool would work doing it that way.

[AMCNitro]

Ron, I understand, and like your tool suggestion, but I was planning on doing this using full rotary motion on a 3 axis vertical, and I don't see how your tool would work doing it that way.

The way I see it, and Ron correct me of Im wrong(probably will be), you set the tool on side of the part on centerline, and you spin the rotary as you feed on X.  Like a thread...

[crazy^millman]

The way I see it, and Ron correct me of Im wrong(probably will be), you set the tool on side of the part on centerline, and you spin the rotary as you feed on X.  Like a thread...

 

Correct, but you will go clockwise for one set of serrations and counter-clockwise for the other. The overlap will create the diamond pattern your are looking for. Again where the angle of the cutter you use will be important. To much then you have to worry about not getting the desired effect. Need to map out our circumference and then figure out how many you will need. I could model up an example if you want me to.

 

Now you need to decide how many serrations? If you go with 30 then need to do a little math.  We know then our angle spacing is every 12 deg we are going to have a cut. Then we need to decide on the helix angle we are going to use to draw the helix along the diameter. Once you have that figured out pretty straight forward from there I would think.

[Robert Ouellette]

i have used an endmill to do the same thing. just instead of cuting on center line and rotating as you you feed along x axis you set the tool so it is on the 45deg point of your part and then rotate and feed. i have cut hundreds of parts like this and they come out perfect.

[crazy^millman]

i have used an endmill to do the same thing. just instead of cuting on center line and rotating as you you feed along x axis you set the tool so it is on the 45deg point of your part and then rotate and feed. i have cut hundreds of parts like this and they come out perfect.

 

Yes that would work well also.

[Roger]

Ron, an example would be FANTASTIC!  There are 26 revolutions, and the outer diameter is 1.3", any other information you need?

[crazy^millman]

Here you go sir.  https://www.dropbox.com/s/1op4ua8ex8dsis0/5th%20Axis%20Knurl.mcx-9?dl=0

[Robert Ouellette]

that is what my parts look like also. very sharp and they are very sharp. oh did I say they were sharp. don't ask how I now they are sharp.

[David Colin]

Here is a toolpath example on part designed by Ron. Can't really be machined like that though but perhaps it will help.

 

https://www.dropbox.com/s/2dkrvejuceqkin5/5th%20Axis%20Knurl.mcx-9?dl=0

[crazy^millman]

Here is a toolpath example on part designed by Ron. Can't really be machined like that though but perhaps it will help.

 

https://www.dropbox.com/s/2dkrvejuceqkin5/5th%20Axis%20Knurl.mcx-9?dl=0

 

Bigger diameter tool and that would get you very close. See you like Morph between 2 Curves.

 

Thanks I like reading French.

[David Colin]

Helix is pretty big so i m not sure a bigger cutter can do it better.I ll try it. And yes I like this toolpath too ☺powerful, versatile with a lot of control.

(Et je préférerais pouvoir écrire en francais

[Roger]

Ron, David,  FANTASTIC!!  I might be experimenting this weekend on this, and you've both been very helpful on this.  I think for now, I'll try it with an endmill.  I'll let you know how it goes.