This is just a link to Vectric's Vcarve Pro's tutorials. They are a great resource.
Standard (fastest) seems to be fine for most jobs.
1. All jobs will be ALONG X and WRAP Y.
2. There is only one post processor and it outputs mm
3. You CAN design in inches and it will still output mm correctly.
4. Your rotary axis will be set up so 1mm jogged is actually 1 degree rotation.
5. Jogging your rotary axis must always be in mm. You can switch back to inches for jogging X and Z..
It's important to consider your model when wanting to do 3 axis rotary carving. it only can carve straight down, and only to the center point. So overhangs will not be carved, nor dips in the model that go beyond the center of the axis.
Things you need to know
On larger material, the end cuts next to the stock that's left can cause you to use excessive stick out of the bit or cause the collet to crash into the material. Avoid this by adding the 3D pyramid tabs to both ends the same height as the material. they can be stretched out left to right beyond the material boundary just to get the ramps to look correct in the 3D view. Use material boundary for roughing and add a box slightly narrower than the material for the finishing pass. leaves a nice ramp that ensures the collet will not hit.
Use my calculator to figure out your steps per mm. an example is:
100 current steps per mm (CSteps)
sent a jog 600mm (Dsent)
Only went 593mm (Dtraveled)
Gives me a new steps per mm of 101.180 (SPmm)
SPmm = ((Dsent*CSteps)/Dtraveled)
101.180 = ((100*600)/593)
JOB SETUP :
I used a set of helping hands meant for soldering to hold a piece of wire rod with a sharpened tip. I put a allen/hex wrench in the jaws of the rotary. I pointed the sharpened point at the corner of one of the hex points making sure that one, the hex wrench wasn’t too long that it would hit the base during rotation, and two it wouldn’t hit the pointer.
Use my calculator to figure out your rotary steps per mm. an example is:
200 steps per rotation stepper motor (MSPR)
Micro stepping of 8x (MS)
6:1 Drive ratio (DR)
360 degrees for 1 revolution
Gives me 26.667 Steps per degree (SPD)
SPD = ((MSPR*MS)*DR)/360)
26.667 = ((200*8)*6)/360
Select lower left as shown. You will zero your bit on the left side of your wood blank near the chuck.
How I probe :
Welcome to the world of rotary CNC! This design and strategy of GRBL configuration is the first of it’s kind. Up until now, people have been recalculating their rotary steps per mm for each job or using secondary software to wrap a flattened out rotary job. Vcarve has introduced a new Rotary job capability with the roll out of version 9.5.
first cuts video :
X AND Z AXIS:
Take a look at this Batman model. The parts that you see right away that will not carve is the ruffles on the shoulder and points between the ears.
Enter job size. If starting with and odd shape log or uneven surface, make sure to measure the diameter at the widest part of rotation and use number a little bit bigger. This will ensure your roughing will not cut too deep the first rotation and lose steps.
This is what is looks like imported into Vcarve.
Here is a simple excel calculator that helps figure out your rotary steps per mm to be degrees. the correct steps per mm will give you 1 perfect complete rotation when jogged Y360.
3D IMPORTED MODEL SELECTION :
After setting steps per mm, test for accuracy.
Set the jogging units to mm
Set the jog distance to 360
Send it once and see if the pointer is pointing to the exact same place on the hex.
If so, here is the absolute best way to check for accuracy. Any bit off on the steps per mm each rotaion sent would be stacked the more revolutions sent in the same direction. Send it around 5 times or more. If it still ends up in the same spot, you are good to go. Most rotary jobs only use the first 360 degrees of revolution.
* Added moving chuck over to access screws first. I found that to be easiest while squaring mine.
TRAINING AND SETUP
REDUCING SQUARE STOCK TO ROUND :
adding a post "tab" :
ALWAYS select Along X Axis.
SETTING UP TOOLING FOR THE DEMON :
Here are instructions on how to square your Rotary Demon CNC machine. The front to back alignment is actually not as critical as you would think because most carves will be 360 degrees. I was a good 1/8" off on the Groot carving and I didn't get any seam lines or imperfections.
Rotary AXIS ( Y ):
squaring your Rotary Demon:
Here’s how I setup my X axis steps per mm measurement. The M5 threaded holes on the side of the Openbuilds spindle mount is perfect for attaching a piece of wire to use as a pointer. I sharpened mine to a point. I start out sending it a small distance to make sure I was in the ball park with 26 steps per mm for the open builds 9mm 3GT3 belt pulley. It’s around 26.643 steps per mm, but calibrate your own. Belt tension can change this number a little bit. Once you are close, use a long send of like 600 mm to check your distance accuracy. Use my steps per mm calculator to calibrate. Z is the same concept but vertical and less distance sent.
Here is an excel sheet to help with adjusting your steps per mm:
To help with roughing, It's best to reduce the square stock to round or at least take the corners off a bit. Here are some charts showing corner to corner dimensions and starting diameters for reduction. It's better to use the corner to corner or a little bit more as your staring diameter, then your pocket depth should be deep enough to get you to the round or close.
This shows how I set up my probe and how I figured out my offset.
POST PROCESSOR :
Vectric training videos :
ALWAYS select Cylinder axis for zero point.
(pictures at right are what happens when you forget)
You will need material to me left so the part doesn't just break off. How much will depend on what you are carving and how heavy/strong the wood is. Every rotary job adds a zero plane automatically. If you add base height to it and set it and your model to combine type MURGE, it will add a post thru the model. The size you enter is the RADIUS, not the diameter. So don't forget the post will be twice as thick as the number you enter.
DESIGNS BY PHIL, LLC
Designs By Phil, LLC
vcarve job setup:
STEPS PER MM CALCULATOR
ROTARY DEMON CNC
Vectric Post Processor Location:
If you use the default install directories, then the private post processors should be moved to this directory:
Example: for Vcarve Pro version 9.5 the directory would be:
You must place the post processor in the directory before starting Vcarve or it will not show up until the next session.
MORE COMING SOON!!!
Calibrating your Rotary Demon:
This was my first test after nailing down the post processor and calibration. Just rounding a square piece that measured 4.0" x 4.0" x 17" long. I was using a 3/4" router bit going 130 ipm @ 40% step over and 0.05" per pass. I could definitely go way faster, deeper, and wider. Next I will try 150ipm to 200ipm, 80% step over, and 0.08" to 0.10" per pass. Needless to say, I'll be needing some dust control!
These are just my suggestions. the finishing pass may be faster along the X axis instead of stepping over. in that case you will want to slow the IPM feed rate to around 200ipm to 250ipm.
adding end ramps to avoid crash: