Deburring in a Vibratory Tumbler
Author: Brian Boyle Date Posted:27 April 2015
The bowl should be filled about 2/3 full with plastic or ceramic media. Start the tumbler while the media is dry. Immediately add a small amount of water (a few splashes) until the media pieces are wet, but not saturated.
Add a few drops of soap or detergent until a very light foam begins to form. If a foam does not form, add a little more water. On the other hand, if the foam becomes too heavy, the work pieces will be cushioned and the cutting action will be decreased. A heavy foam means there is too much soap or detergent or too much water in the mixture and the entire mass of media should be rinsed out and started again.
Once the mixture is correct add the work pieces - about 5 parts media to 1 part work pieces. If the work pieces are shaped so that they will tend to hook together, make the ratio 10 parts media to 1 part work pieces. In the initial run, the load should be watched carefully to determine the cycle time for that particular part. The normal cutting time is between 20 minutes and 6 hours.
For the longer runs, a splash of water should be added every 45 minutes to 1 hour to restore the action as the water will evaporate and the slurry will build up as the work is being done causing the cyclonic action to begin to slow. This procedure will keep the action going for a while, but eventually the whole mass may have to be rinsed and started again until the desired finish is reached.
To determine the end of the cycle, inspect the work pieces to be sure all of the pits and scratches have been removed and there is a uniform finish over the entire part. Most of the work will be done on the outside edges of the parts as they are more exposed to the moving media. The flat surfaces will be scrubbed, but very deep scratches cannot be removed by this method.