Shopbot User Tips
Post-Processors
When creating toolpaths for the PS1 Shopbot, there are now two distinct options:
- Shopbot TC_PS1(Inch) and Shopbot TC_PS1(mm)
- For general usage of the Shopbot (typically cutting)
- Shopbot TC_PS1-NO_SPIN(Inch) and Shopbot TC_PS1-NO_SPIN(mm)
- For dragging, engraving, and other tasks where the bit (may not actually be a bit) must not spin.
Be careful when creating a toolpath file that you select the right post-processor!
Positioning your work
Feeds and speeds
Spindle Speed
The Shopbot does not pick up spindle speed instructions unless you have first opened up the Spindle RPM Control menu (under Tools):
My speeds aren’t changing on my Spindle when I run the warm-up routine and during cut files. What is the problem?
- Note: On ShopBot desktops and MAX, the RPM must be manually adjusted.
The Spindle RPM Control window needs to be open in order for the spindle to change speed. If you see this window pop up during the warm-up routine or software start-up, do not close it. To open it manually, type TR in the ShopBot console (the blank box next to the ShopBot CNC logo). Click on RPM to open the fill-in sheet, and make sure that the correct VFD is selected. Start when SB3 start is set to 1, and the Hz scale is set to 60 for a V1000 spindle and to 100 for a 74X spindle.
The RPM Control window is not available on software versions earlier than 3.6.X.
Perhaps the fact that this can be done via console means that it could also be added to Gcode files by the post-processor? I'm not really sure. I did just notice this, though, a bit lower down in the FAQ:
If the VFD isn't reflecting the RPMs set in the control window, clos SB3, backup and delete shopbot.ini in "C:\ProgramData\ShopBot\ShopBot 3". Reload SB3 and it should work.
I want the RPM Control Window to open every time I start ShopBot 3
This can be accomplished in one of two ways:
1) ...blah blah blah...
2) Navigate to C:\Program Files (x86)\ShopBot\Virtual Tools. Open this file with a text editor like Notepad or SBEdit. Edit this one line of code:
VT = Spindle [&R]PM Control, Virtual Tools\Spindle Control\Spindle Control.exe, 0, 0
Change the last number, which is a zero, to one. It will now look like this:
VT = Spindle [&R]PM Control, Virtual Tools\Spindle Control\Spindle Control.exe, 0, 1
Save the file, close and reopen the SB3 software to see the changes take effect.
This needs to be done only once for your Shopbot login.
Drilling
Cutting Speed [CS] is based on Surface Feet per Minute [FPM or SFM]. RPM = (Cutting Speed(ft/min) x 12/1(in/fr))/Diameter of Cutter(in) x pi RPM = (12CS)/(pixD)
| Material | Cutting Speed (FPM) |
| Low Carbon Steel | 90 |
| Alloy Steel SAE 4140 | 50 |
| Cast Iron | 70 |
| Aluminum | 300 |
| Drill Dia.(in) | Feed per Revolution(in) |
| under 1/8 | .001 to .002 |
| 1/8 to 1/4 | .002 to .004 |
| 1/4 to 1/2 | .004 to .007 |
| 1/2 to 1 | .007 to .015 |
| over 1 | .015 to .025 |
Example: 1/2 in drill, Low Carbon Steel
Dia = 0.50 Material LCS : 90
RPM = 12CS/pi*D = 12*90/.5pi = 2160/pi = 687.5
Feed = .004-.007
| Answer: | 687.5 RPM |
| .004-.007 in. per Rev |
REAMING
Speed - 1/2 - 1/3 the speed for drilling Feed - 2-3 times the feed for drilling
MILLING
Recommended Feed and Speed Rates
RPM = (12CS)/(pixD)
Feedrate = RPMxfxn
n = number of teeth
f = feed per tooth
| Drill Dia.(in) | Feed per Revolution(in) | |
| Material | High Speed Steel | Cemented Carbide |
| Aluminum | 300-800 | 1000-2000 |
| Brass | 200-400 | 500-800 |
| Bronze | 65-130 | 200-400 |
| Cast Iron | 50-80 | 250-350 |
| Low Carbon Steel | 60-100 | 300-600 |
| Medium Carbon Steel | 50-80 | 225-400 |
| High Carbon Steel | 40-70 | 150-250 |
| Medium Alloy Steel | 40-70 | 150-350 |
| Stainless Steel | 30-80 | 100-300 |
Example - 0.50 in HSS two flute end mill cutting aluminum
RPM = 12CS/piD = 12x300/.5pi = 2292 RPM
RPM = 12CS/piD = 12x800/.5pi = 6112 RPM
Feedrate = RPMxfxn = 2292x.005x2=23 IPM
Feedrate = RPMxfxn = 6112x.005x2=61 IPM
| Cutter | Al. | Brass | Bronze | Cast | Low | Med | High | Stainless |
| Dia. | ---- | ----- | ------ | Iron | Carbon | Carbon | Carbon | Steel |
| ------ | ---- | ----- | ------ | ----- | Steel | Steel | Steel | --------- |
| 1/8 | .002 | .001 | .0005 | .0005 | .0005 | .0005 | .0005 | .0005 |
| 1/4 | .002 | .002 | .001 | .001 | .001 | .001 | .0005 | .001 |
| 3/8 | .003 | .003 | .002 | .002 | .002 | .002 | .001 | .002 |
| 1/2 | .005 | .003 | .003 | .0025 | .003 | .002 | .001 | .002 |
| 3/4 | .006 | .004 | .003 | .003 | .004 | .003 | .002 | .003 |
| 1 | .007 | .005 | .004 | .0035 | .005 | .003 | .003 | .004 |
| 1 1/2 | .008 | .005 | .005 | .004 | .006 | .004 | .003 | .004 |
| 2 | .009 | .006 | .005 | .005 | .007 | .004 | .003 | .005 |
| RPM Range: | 2292 - 6112 RPM |
| Feedrate Range: | 23 - 61 IPM |