Pinholes in coating
05-10-2016, 08:22 PM,
#1
Pinholes in coating
I can't seem to find any information about this problem....pinholes.
I have sprayed a lot of rotors and have not had any issues, but every once in a while, I get pinholes in the coating....only in the valleys/lows. The traverse speed and rotational speed are the same. Gun angle is about the same....not exact with each rotor, but very close. Kerosene is the fuel and it is kept outside in barrels...in partial sun. Any ideas people? I am sure that you all will have some ideasSmile

Thanks!!
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06-01-2016, 03:49 PM,
#2
RE: Pinholes in coating
Not sure of " pin holes" in coating - this is generally a welding issue! However, if pin holes refers to voids / porosity in coating - I would check the surface temperature during coating as well as the distance of spray.... you should try to control the surface temperature during spray to 100 deg C and spray distance of no more than 8" from the center of the substrate for most guns...

Shantanu Newar
Eastern Metallizing, Kolkata



(05-10-2016, 08:22 PM)PrecisionCarbide Wrote: I can't seem to find any information about this problem....pinholes.
I have sprayed a lot of rotors and have not had any issues, but every once in a while, I get pinholes in the coating....only in the valleys/lows. The traverse speed and rotational speed are the same. Gun angle is about the same....not exact with each rotor, but very close. Kerosene is the fuel and it is kept outside in barrels...in partial sun. Any ideas people? I am sure that you all will have some ideasSmile

Thanks!!

Reply
07-11-2016, 02:41 PM,
#3
RE: Pinholes in coating
Shantanu,
Thank you for your reply! I was indeed referring to porosity in the coating. I will definitely look into the surface temp of the part that is being coated and the gun distance from the part. We are currently running tests on gun spray angles and location of gun relative to the part being sprayed. I will add temperature to the testing matrix.

Thanks Again!!
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