Previously on part one.....
Without the resistance of the blower fan and suction of the vacuum filter assembly, this motor spins way faster than what the label states. So fast in fact it wants to tear itself apart while merrily dancing across the shop floor despite being mounted on springs (or maybe because it's mounted on springs?)
So, I need to figure out a way to slow the motor down or reduce the vibration component.
My first thought is to reduce the size of or modify the shape of the metal strip I added to the motor axle.
I think doing this only reduces the vibration. The motor will still be spinning way too fast and determining the right size of strip may be hit and miss to get exactly right.
How about controlling the motor speed? I think this will be the easier route.
Digging through my box of household electrical stuff, I found two incandescent dimmer switches that should work. They are designed for AC power (as is the electric motor) and this would add the ability to fine tune the vibratory effect for best results.
Before that however, I need to finish creating the parts bowl. First I inverted the bowl and traced a circle on a piece of spare lucite (plexiglass):
Cut the circle out using my bandsaw...... that's when I realized the centre section of the bowl sits above the rim:
To secure the new lid, I used a piece of hollow threaded rod. I screwed it into the top plate of the tumbler and l left it long enough to add a cap to hold it down tight to the bowl:
To hold the lid, I found an old powder scoop that fits perfectly over the bowl centre. That and a washer and nut hold everything down nicely:
Now that everything is built, back to slowing down the motor.
I added in the rotary dimmer switch. It has an off position when turned counter-clockwise all the way. I'll tide up the wiring once I figure out if this is going to work as designed. The picture was taken prior to creating the lid. Using the dimmer works!
Time to test the machine....
First, add the tumbling media, in this case a couple of scoops of clean clay cat litter. Then add some dirty, greasy and rusty test parts:
Close and fasten the lid..... all secure and "go for power-up!" The vibrating of the tumbler makes it hard to get a clear picture, but the media very quickly envelops the parts. As it tumbles, they occasionally come back up the top:
The tumbler is NOISY! I suspect the bolts between the levels of the tumbler are vibrating against the bowl. That should be easy to fix. Perhaps it might have to be run outside. After letting it run for about five minutes, I decided to have a look at the progress. Even after only 5 minutes, the parts are obviously cleaner and devoid of the grime they entered with:
Although the parts come out a bit dusty, clearly this method and machine I've built works very well, even at a short duration. I'm planning on running a longer test this afternoon and will post more details.
Time until takeoff
Husband, father and 911 dispatcher. Long time pilot with a licence that burns a hole in my pocket where my student loan money used to be. First time aircraft builder. Looking to fly my own airplane.