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Coating for Cast Iron Shot Put?

Greetings,

I am a college track coach and I wanted to get some suggestions from this forum on what process would be most effective in protecting our cast iron shots. Some of them come with a paint coating, but over a few seasons it will begin to chip off. The shots are subjected to the abrasive action of landing in sand when thrown, so a durable process is the most important criteria.

I've tried stripping any rust off using naval jelly [on eBay or Amazon] and then spray painting, but the finish just doesn't hold up. I'd consider either a surface treatment or a protective coating treatment, but what would be best? Blackening? Plating? Powder coating?

Thanks,

Paul Markel
Track Coach - Holland, Michigan, US
2005

As they are going to be subject to heavy abrasives I would suggest getting them plated, a heavy chrome or bronze plate would be good I think (powder coat will hold up too, but I'm not sure which will be best for this application). You could always make polishing them a punishment for those in your program that misbehave......

Marc Banks
- Elizabeth City, North Carolina USA
2005

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Being an ex-hammer thrower, I found the best way of keeping the implement clean was to use it regularly and to wipe it off after use. The use and abuse that shots, hammers and discii suffer will not give any coating a real chance of long term survival. Constant use will ensure the rust is knocked off and the surface will be constantly polished. Sand or soil is an excellent abrasive! I must admit I have never tried plating the implement, but in the case of a shot I would be loathed to, in case the plating chipped and caused sharp edges to occur on it - the idea of being chased by an irate 250lb shot putter who has just ripped open his jawline on a piece of sharp metal doesn't appeal to me!

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2005