Hammer powder coatings

Hi,

I am a paint and coating engineer who works specially on powder coating. As I have seen, controlling the texture patterns in hammer finishes depends on many factors such as mixing conditions, type of metallic pigments which are used, etc. Could you please help me about the effects of spraying conditions (such as voltage, air pressure and so on)on the patterns?

Regards,

Hi Leila,

As in the production of "hammer" finishes, there are many aspects in the application that can effect the final texture of these powders. One of the main influences is the voltage at which you spray and the earth of the object. For a standard powder coating you would set your kV at ~70kV - ~80kV, for a hammer finish you will need to turn down the kV, use as a starting point 50kV. When you set this kV it is very important that you have a good earth. It is sometimes a case of trial and error, so keep adjusting the kV until you get the desired finish.

Other aspects that may effect the final finish are:

Air Pressure - Turn the air pressure down until you get desired results. Reclaim - Due to most hammer finishes not being bonded it is very difficult to reclaim the oversprayed powder. You will almost certainly loose texture and colour if you try to reclaim.