How far back should the fire go?

[Manatawny]

Hi, Everybody.

As I extend my block arch from 1 pan to 6, this year, I'm wondering how far into the arch the fire itself should go?
Is there a general rule of thumb, like, for instance, that there should be fire proper for, say, 1/3 of the total length, and then the ramp should start there? Or do you simply light a fire under the first pan, and trust the stack to draw the heat under the other 5 pans? In which case, how far in should the ramp start?

I'm looking to pick up a used fireplace grate; but, now I'm wondering if I need more than one?

Thanks for your help!

[motowbrowne]

I'm not sure about a rule of thumb. I think my 2x10 had 30" deep grates. It had a fairly shallow ramp. I haven't measured my 4x14, but the grates don't seem longer than 48". It was set up with a very steep ramp.

Of course, both of those were flue pan rigs, so your setup will be different. In answer to your question, though, yes the stack will pull the heat under the length of the pans. Make your firebox deep enough to burn the size wood your want.

[madmapler]

I agree with everything Moto says. Maybe keep a few inches between the top of the ramp and the flat bottom pans. You can always play with the opening before it goes up the stack.