Fast CNC

What is the big key to the speed of this machine?
http://video.google.com/videoplay?docidE50191913648686955#docid=-1684953814431369082
Looks like they are cutting about 1/4 plate at a really aggressive rate. Obviously ramping and spray lubricant help, but that is not all it takes to cut that aggressively or is this also a super high speed spindle?
My experience so far has been that if I try to take off more than about .003 by .250 per pass I can run about 20 IPM with aluminum with lubricant. This looks like they are taking about .250 by .1875 in a single pass after ramping in at something like 60 IPM.
Excuse my numbers if they are off since I can only judge this process by what is shown on the video and guess at the dimensions.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Bob La Londe wrote:

http://video.google.com/videoplay?docidE50191913648686955#docid=-1684953814431369082
Definitely a high speed spindle with a fair amount of HP, high pressure coolant to clear chips, and most importantly rigidity.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I was thinking spindle speed had to be the key. Everything else you can see. How fast do you think they are spinning to be able to do that?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
maybe 5" per second on the long runs would be 300ipm. 4 flute cutter, .003" tooth loading, would be 50k rpm. Tone down the tooth loading a bit would be a 30k rpm spindle. The chips are distinctly flat pieces so the tooth loading has to be right up there. Probably running an end mill in better shape than the ones I have laying in my tool box. :)
Bob La Londe wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Bob La Londe wrote:

Guessing based on sound at least 10k, perhaps 15k. Has to spin fast to keep the chip load per tooth low at those feeds.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I turn 10K with my machine and there is no way I could get a fraction of that speed or chip removal.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Bob La Londe wrote:

Not sure what machine is in the video, but some of Datron's machines run 40k spindles.
Jon
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
From the info I've read about them, these types of machines are referred to as HSM, for high speed machining.
Spindle RPMs in the tens-of-thousands and the overall machines are built specifically for this purpose, not just a standard machine with a powerful high speed motor retrofitted.
The videos are very impressive, but I could enjoy spending a day just watching various parts being machined.
They are so fast/efficient that they can machine a part from solid stock, that would've previously been made by fabricating the part with several pieces of sheet stock, such as airframe structural members.
--
WB
.........
metalworking projects
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Bob La Londe writes:

Gotta be that salsa music. Chukka chukka tick tick tick ...
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Given the typical use that the machines are sold for, it may well be 1/8" plate for panel fronts, with the square holes being for 1/2" push button switches.
Mark Rand RTFM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Bob La Londe wrote:

http://video.google.com/videoplay?docidE50191913648686955#docid=-1684953814431369082

I read a book on some early experiments at Boeing with high speed machining in the late 60's I think. They were running a huge Cincinnatti horizontal mill with a 1/2" end mill at 75,000 RPM and 80 Hp, 600 IPM feeds and 640 cu. inches of aluminum removal per minute. These numbers made my head spin, 80 Hp into a 1/2" end mill! YIKES! I put the book back and figured I'd never get into that class of machining.
Part of the trick is to maintain totally INSANE feedrates to keep the heat generation moving along as fast as possible. Much of the heat goes off in the chip, but you want to prevent the aluminum, especially, from warming up much. I think the tests I refer to may have been run dry, to protect the carbide tools and also because at these metal removal rates all you'd be doing is boiling a huge amount of water and not really cooling the work or tool much.
Jon
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.