Hey guys, as you can see, I’m new to the forum and I’ve found it to be a wealth of knowledge so far. I am planning a DIY outdoor furnace but I have a few question regarding the design. I plan on using .5” carbon steel tubes as both the firebox and water jacket with a forced air fan. My problem is figuring out whether to add an ash pan and grate. I have no experience with outdoor furnaces so the information that I have is based only on research that I’ve done.
If I didn’t add the pan and grate, it would be much easier to fabricate. Not having these would also make it less likely to leak because there would be fewer welds and I wouldn’t have to replace grates every so often. I would have to shovel ashes but from what I understand, a forced air furnace provides a more complete burn and far less ashes. I’ve been told too that allowing the ashes to stay beneath the coals allows for better insulation and also allows for a better burn.
If I did add the ash pan and grate, it would obviously be easier to remove the ashes. However, it makes the furnace harder to fabricate, more likely to leak, and I would also have to replace grates every once and a while.
So what’s your opinion? I don’t mind shoveling ashes but will I really have to do it that much with a forced air system? The pros and cons seem to be telling me not to install the ash pan and grate. Is there anything that I’m not thinking of?