I have been cleaning up some stock cast iron manifolds, removed surface rust with abrasive paper and wire wheels,and they are now as clean as possible without blasting. Next step is what to paint or coat them with to keep them rust free and looking presentable ? In the past I have not had much luck with the so called VHT spray can paints. I have read about an American product called callyx that is a paste that you apply with a small stiff brush, it bakes on with the heat and can be retouched.Sounds good but has anybody here used it or is there another product that will stay on hot cast iron ?
A pal of mine always used to get his hard chrome plated as used on hydraulic rams and industrial stuff, it seems to last a very long time and turns a really nice hue of dark blues, much cheaper than decorative chrome plating
As already mentioned, it’s down to surface prep rather than the product. They need to be super clean and keyed, not polished smooth with wire wheels. Get them sandblasted and coat them immediately, even leaving overnight can get surface bloom with cast iron from the moisture in the air. Even rattlecan VHT will work if you do this.
Thanks for all the helpful replies. I understand the point about cast iron being hard to prep.The casting is pretty rough in places and just about impossible to completely clean up.On old Jags they used to use a finish called vitreous enamel,but I have never seen any company offer it. I suppose stave enamel could also work, but not having tried it could be expensive on parts that are hard to coat because of the rough sand cast finish ?
I'll try to find the ad again, because it might have been vitreous enamelling rather than stove - I don't know the difference. You could probably phone them up for their opinion on what you have - I seem to recall the ad was aimed at exhaust manifolds. Whichever treatment it was, it was not suitable for a steel tubular manifold.
Just in case anyone else wanted to know I tried a little research on the TR6 an E-type forums and the word seems to be that stove enamel will not last and there is a vitreous enamel firm in the Black Country somewhere but they are very expensive and the finish just ends up looking like BBQ paint if you drive your car much. Think I will go with the stove polish, at least it is cheap and can be touched up when needed.