Most standard 60HZ AC motors come in approximately 3600 RPM or 1800 RPM. The barrel sander needs to spin at about 30 RPM. To achieve this, the following approximate pulley sizes will be used:
- 1800 RPM motor
- Shaft to 2″ Pulley
- Belt to 7.5″ pulley
- Shaft to 1.75″ pulley
- Belt to barrel (approx 23″)
- End Result is approx 30 RPM
(This was from memory so might be fractionally off).
Here is a render of the pulley assembly (draft):
The inside of the barrel tumbler needs a polygon (made from wood) in order to (a) give enough “traction” to turn the contents, and (b) protect the barrel from repeated impacts. I’m going to use Oak or Maple to do this. Based on the width and thickness of available material, I chose a 9-sided polygon.
Here is a picture of the CAM operation prepared using Fusion 360. I will make nine of these with just a fraction of an inch extra that I can remove on the jointer while getting a tight fit.
Machine M002 is in the works. It is a barrel tumbler for wooden parts. This project will allow us to knock sharp edges off of small wooden products by the hundreds at a time. More to come!
Here is a screenshot of some of the parts we’ve designed for the Stain Dipper. All of the mechanical parts are in the design and correctly positioned and all the hardware has been ordered…
Here are several of the parts from Fusion 360
Here is a servo motor mount and custom made pulley.
Here is a small piece of Nylon used to connect a 1/16″ cable with a aluminum tube.
We’ve been doing some research into air knives and considering ways to make staining of thousands of small parts faster. Dip it into the stain, and have a captive air knife blow the excess off (dripping back into the bucket) as the part is pulled out.
The PVC tube will be hinged so it can be opened for cleaning. The air knife assembly will be near the top of the tube.
Did some checking on PVC compatibility with stain and it seems to be acceptable: https://www.berlinpackaging.com/insights/chemical-guidelines-for-plastic/
Here is a possible air knife kit. http://www.exair.com/index.php/products/air-wipes/super-air-wipe/saw-kit.html
Now just need to design the servo motor mounts, air knife mount, and misc. other structural components.
Here is a render of the shoe shelf design. This was done using Fusion 360 software.
Wouldn’t it be cool for the kids to have a shelf that looks like a pair of shoes, to put their shoes on?