I’m having a bit of a difficult time finding an inexpensive solution for my rocket mass heater riser. I stopped in a Moerke well drilling yesterday. They were willing to offer me a piece of well casing at cost, just under $10/ft. That would make the cost of the riser ~$50. Ouch. With the increase in metal prices, an inexpensive riser is a bit like hens teeth. All the scrap is being turned in for recycle. I’ve been haunting the recycle yard with no joy.
I could use round flue liner at ~$15/18″ length. I’d need 4 lengths to get the total height I need. The total $ for flue liner eclipses the cost of the well casing at cost from Moerke. Plus I’d have to figure out how to join then cut the resulting mess to 53 1/2″. Hmmm.
Alternatively, I have the option of pouring the riser using refractory cement. I have all the ingredients. I’m a bit hesitant to do this as I’m already veering quite a bit off the straight and narrow in building this rocket mass heater. I can test fire the constructed riser to ensure it doesn’t explode or disintegrate or . . . well, you get the idea. And if I’m pouring the riser, why am I not pouring the burn chamber . . . You can see if I’m given an inch I’m gonna try for the mile. It’s just the way my brain works.
The weather still sucks. Wad’s off work tomorrow and we’re going to start on the foundation for the sun porch. I hope we have nicer weather. The forecast is for rain both Friday and Saturday. I want to try and get a batch of refractory cement mixed so I can see how it works. I don’t need to mix much for testing . . . a little over a gallon total, I think, just enough to see how it holds up to being toasted. I will need to pack it firmly into whatever I use for a mold. Air pockets are a bit of a guarantee it will end up in bits when fired off.