'65 Sidepipe Covers

[Joe Ciaravino]

Re: Anodizing

Jeff:

Although the NCRS judging manual states that the dull recessed areas of the N14 sidepipe covers are painted dull aluminum, I suspect that this is incorrect. In the process of polishing out some deep scratches with fine emery, I had to break through a hard surface layer (likely the oxide deposited from the anodization process) before the abrasive would start cutting through the scratches. I found this same condition on both the shiny and dull areas of the covers. At this point, it seems that the raised ribs were highly polished, and the recessed areas were left satin finish, then the whole cover was anodized to offer corrosion protection.

If you have any info on the anodizing process, or know of a shop that can do this, I would welcome the info. For now, I'm going to get more info. so I can do the job properly.

Joe

[Jeph South]

Re: Anodizing

I will be able to get the current commercial standard tomorrow. I will not be able to obtain any GM specifications, past or present. And it will not tell you how to actually perform the operation. But hopefully the information I provide will help you find somewhere that can do what you are looking for. The basic process works very well, and has been used extensively in the aircraft industry for decades. I have anodizing done at work, but unfortunately I cannot get private work performed. (Otherwise all of my chrome would be PERFECT!) I will talk with a plating expert friend of mine tomorrow (I include anodizing and conversion coating in plating) and see what else I can uncover. He may be aware of somewhere to have it performed. Jeph

[Andy]

Re: Annodizing (not so easy to "strip")

I am by no stretch an anodizing expert, but I am in the process of installing an anodizing line at work. What has been stated thus far about the anodizing process is correct for the most part. However, I don't think it will be as simple as just stripping the existing layer of anodize and adding a new one. A surface that is anodized, does contain a layer of film, but a portion of that layer contains the original surface. As stated previously, the surface is corroded before the sealing process creates a film, so the original surface is deteriorated before the hard finish is applied. So a portion of the resulting film actually consists of the original aluminum. Therefore, if you apply a 30 micron thick layer of anodize to an aluminum surface and want to mill it off, you will take about 1/3 (10 micron) of the original raw material away to get back to the unanodized material. Keep in mind, if you do strip the anodizing off, you will be taking some of the aluminum with it.

I hope this information if helpful. Good luck.

[Jephrey S.]