Introduction: Air Assist / Vacuum Port for Small Engraver
I'm starting to work with machinable wax. This carving is approximately 1" in diameter and 1/8" thick.
It was cut using a 0.005" tapered ball end mill. The bit is so fine, the tip of it is smaller than a pin.
It makes very fine dust that needs to be blown out of the cracks, or it is a real pain in the butt to deal with after the fact.
It took 7 hours to run this job. The bit moves 0.02 milimeters each pass. Watch the video and you'll see the action.
Go to the next step to see how I solved the problem of killing an entire day and also hyperventilating.
Step 1: Measure Your Spindle and Cut a 3/4" MDF Support
I used the shopbot at TechShop to make a support out of MDF.
I measured the diameter of the spindle and made a 3 1/2" x 5 1/2" plate with a hole that was 1/16" larger in diameter than the spindle.
I used a nylon tie to hold it on to the Z axis. I wanted something that would go on and off easily and I did not want to have to tap something.
I went to Harbor Freight and bought a couple pneumatic parts. A quick disconnect, and also an air gun. I used the cylinder from the air parts to serve as the air assist that blows the dust particles and swarf from the surface of the part as it is cut.
The only trial and error part of this project is making sure that the air nozzle lines up properly so that the major force of air is hitting the router bit.
You need a hefty air compressor to keep up with the constant stream of air that is coming out of the nozzle. I find that it needs about 25psi to blow all the small chunks of wax off. You can see, some adheres to the wax anyway.
I also cut a hole the size of a shop-vac hose and mounted it at the end of the X axis. The air stream from the nozzle along with the vacuum port picks up all of the little pieces of wax dust.
This is a great system. You can keep an eye on the progress without having to babysit the CNC machine for all day.
I made it at Tech Shop.