Sometimes it happens that the effectiveness of sandblasting changes incomprehensibly. The added abrasive in the injector sandblaster is less effective (the air/abrasive mixture is poorer). Alternatively, the blasted mixture pulsates, "sizzles". Very often the change in weather or the change in relative humidity is to blame.
What to do in such a case?
Often, simply adjusting the false air intake will help. In our ITB pro sandblasters this is adjusted on the mixer (at the bottom of the box). The gap should be between approx. 3 and 8 mm. In wet seasons it is recommended to make the suction opening larger and vice versa.
The size of the required hole may also vary depending on the coarseness and type of abrasive used.
If this does not help, check the cleanliness of the sandblasting abrasive and pass it through a fine sieve. In doing so, check that there is no visible, excessive proportion of sandblasted glass grit in the abrasive. Of course, impurities of all kinds are undesirable in the mixture. If they are, replace the abrasive with a new one that should adhere better.
Note: Sandblasting workshops equipped with a compressed air dryer will obviously have fewer problems with moisture.
You can try out the box setup in our GDS ACADEMY training centre.