Originally Posted by Clawsie Machine Ok a couple of questions here first.
1. I usually use MasterCam's recommended feeds and speeds when setting up a tool, BUT how acurate are they?
2. How do I load in this "free" ME consultant 2.0 software. I tried to play with it and it looked up my system?
3. I would like to get a couple examples for some cutters I'm looking at:
A. 3/8 2 Flute carbide cutter for Aluminium. From there manufacturer site:
" Slottling up 1 X "D" .008 with SFM up to 5000."
B. 1/4 2 Flute carbide cutter for Aluminium.
"Slottling up 1 X "D" .004 with SFM up to 5000."
Now how would l figure these out? Basic, well explained process would be best, I don't want to assume anything with this due to the amount of work with this production job coming up. Machine has Max RPM of 6500!
Would like to run these E/mills under max RPM, say +- 5500 RPM or there abouts.
I have really know idea on how to figure out the IPM or RPM for a material by using the SFM rule. I usually use RPM X Chipload in load per tooth X # of teeth. Like 2500 RPM X .003 X 4 teeth = 30 IPM!
I want to convert ALL my programs to "G95" for inches per tooth in relationship to RPM and not IPM. I feel that with production this might be a better way to get the most out of each cutter?
Thanks in advance, John  |
This is what I can offer.
The first value needed for any material is the SFM in which that particular alloy can be cut and with what cutter material is being used. Obviously higher with carbide than HSS. This will relate to the spindle speed in RPM for the circumference of the cutter itself.
If the material has a SFM window of say 200-300SFM and the cutter is .375 in diameter, then:
RPM=(sfm*12)/(Cutter Dia * Pi)
2037 RPM=200SFM for a .375 cutter.
27,500RPM =2700SFM for a .375 cutter.
Use whatever the limit for the recommended SFM of that particular alloy and adjust accordingly. If your spindle does not meet that SFM, then go to the top RPM and chip load as you already are. It should not matter how the feed is applied, as long as the IPT feed rate is relative to the RPM while still in harmony with the present conditions. Ultimately the operator must make some of those decisions with the programmer. Preferably before the unforeseen is found too late?
The chip load that the OEM gives may very well be for perfect conditions in all other areas of rigidity. If the application can handle it, then push it as hard as you dare. Those conditions just do not happen very often. Something will put limitations on full tilt chip loading. Efficiency must take into account the weakest link, including susceptibility to chatter, surface finish and dimensions. Just because someone puts a spec on the capacity of the cutter, won't mean that it applies in all cases. To many variables to count on there.
DC