half-pint wrote:Have a question for everyone on this. My stove got a new set of triangular grates in it's restoration. Would like to hear some expert opinions on how to season these three sided grates for service before the heating season gets going. Going to be setting up my stovepipes here over the weekend. First time the temp drops below 50F here night or day I plan to warm this 'ol girl up just for the simple fact of doing it. I may have to keep the A/C on too, but I am impatient and a can't wait to try my hand at this stove.
This question comes up from time to time. So here's a bit of technical info on this. Your grates are likely grey cast iron. They are probably made to ASTM A319. (but only your foundry knows for sure )
Heat treatment of grey cast iron is done for four fundamental reasons: 1) improved machinability; 2) improved wear resistance; 3) improved strength and 4) dimensional stability and stress relief - this last case is what you want for your grates. There are lots of proprietary formulas for doing that, but here's a generic one:
Heat the parts slowly to between 900 and 1100 * F. Hold for an hour then cool slowly (about 100 * f per hour) to between 400 and 600 * F and then you can pull the parts out of your oven. The whole cycle take a good number of hours depending upon what all your set points are.... Note also that the temperatures are well above any home kitchen stove I've ever seen.
So really the best place to do this is in your stove where the grates are going to live. If you think about the parameters above, you'll see that all the advice you heard from others on here is pretty darned good . Take your pick of which process you want to try. Bear in mind that 1100 * F means the metal is actually glowing at a dull red. See the following link:
http://www.thefabricator.com/article/tu ... rfing-tool
Part way down the page there is a color chart "Steel color vs temperature".
Hope this helps....