Sir,

I am a technician helping to improve coating quality (Coating Specification PWA 1347). I have a titanium part with has a "U" shaped channel, not more than 0.150 inches wide, and that needs a plasma repair to restore it dimensionally. One side is blind, the ends are open. Currently we are using a twin wire spray system to bounce the coating off a surface opposite the blind side to coat the blind side. Needless to say it's a mess. The system being used does not offer much in spray adjustment. It's a royal nightmare for the machinists to clean the channel out without chipping the coating. The bounce technique is verbatim out of work instructions to coat the part. Any ideas on how to improve on this?

Thanks in advance for all imput.

Best regards

tdougher

tdougher Wrote:Sir,

I am a technician helping to improve coating quality (Coating Specification PWA 1347). I have a titanium part with has a "U" shaped channel, not more than 0.150 inches wide, and that needs a plasma repair to restore it dimensionally. One side is blind, the ends are open. Currently we are using a twin wire spray system to bounce the coating off a surface opposite the blind side to coat the blind side. Needless to say it's a mess. The system being used does not offer much in spray adjustment. It's a royal nightmare for the machinists to clean the channel out without chipping the coating. The bounce technique is verbatim out of work instructions to coat the part. Any ideas on how to improve on this?

Thanks in advance for all imput.

Best regards

tdougher

Dear tdougher,
unless we have drawing of the part it will be very difficult for any one to visualise the actual problem and give you solution.
You can send me the drawing on my E-mail
Vijay Deshpande

tdougher Wrote:Sir,

I am a technician helping to improve coating quality (Coating Specification PWA 1347). I have a titanium part with has a "U" shaped channel, not more than 0.150 inches wide, and that needs a plasma repair to restore it dimensionally. One side is blind, the ends are open. Currently we are using a twin wire spray system to bounce the coating off a surface opposite the blind side to coat the blind side. Needless to say it's a mess. The system being used does not offer much in spray adjustment. It's a royal nightmare for the machinists to clean the channel out without chipping the coating. The bounce technique is verbatim out of work instructions to coat the part. Any ideas on how to improve on this?

Thanks in advance for all imput.

Best regards

tdougher

Hi tdougher

to the Surface Engineering forum.

I can visualise your problem to some extent and find it interesting that you are trying take advantage of an effect that most would wish didn't occur . I agree with Vijay that a little more info on the part geometry would help. What is the depth of the channel and what sort of spray angle can you achieve? What is the coating? May be the answer lies with machining the channel to suit the your spray conditions.