Soapstone blocks in cookstove oven?

[szmaine]

Spent the day blacking the old cookstove (oh, why, oh, why didn't I paint it).

Do to the remoteness of the kitchen L from our new stove it looks like we may be firing it up more on those really cold nights to keep the pipes from freezing (yeah, we have a furnace but even if we use it the kitchen heats poorly)

I'm having this potentially hair-brained idea that if I filled the oven with soapstone when not in use we could get more out of it.
A quick search of the internet revealed shocking prices for soapstone brick - but perhaps I could pick up rough scraps from somewhere, I think there may have been
some quarries in my state.

Do you think it would help keep the room warm longer? Or is it not worth flexing another brain cell over?
Is there another cheaper material that would do the same?

 

[tickbitty]

The middle school around here remodeled a few years ago and apparently tossed the soapstone countertops in the science rooms, which kills me!
Many stone sellers who sell marble for countertops and etc also sell soapstone. I imagine you could get some pcs from somebody like that.

 

[KeithO]

Call (broken link removed to http://www.greenmountainsoapstone.com/masonry_heaters.html)

Their thick (60mm) soapstone slab material was the most reasonable I found anywhere and if you are close enough to collect it will be a winning deal.

 

[littlesmokey]

Quarries may not be able to help you, because of the size of pieces they mine. You should be able to find a processor close by. They usually have off cuts or seconds that are cheap, sometimes free. I get glass this way, always free. Jagged and irregular pieces can be cut to standard shapes often with a handsaw. SS is soft and a good one time carbide blade will do the job. One time, because it might cost more to retip and sharpen than replace. clamp stone to a solid surface outside, put on eye protection, a face shield and a good respirator and cut. Don't do it all at once, take shallow cuts, the blade will track after a few passes.

Old stove stones were usually about 1 to 1-1/2 thick. They seem to heat best. don't stack them tight, but sticker them (like wood drying) small shims from your cuts work well. When they are heated, I would take them out of the stove, so they heat your room and not simply go up the stack.

I might not be a fan of this idea, but there were, "summer-stoves" insulated boxes that would slow cook food all day made from the civil war on. Real popular around the turn of the 20th century. Morning the stove was heated, breakfast cooked bread backed and dinner in the old fashioned crock pot was put on for the evening meal. It was hot enough to cook food, so might add some reasonable heat to the house.

 

[Corey]

As I always say every time this comes up...technically yes you'll get more heat - practically, not very much. Even if you can stuff the oven with several hundred pounds of stone and get it up to several hundred degrees, the amount of heat stored is probably only going to amount to 15-30 minutes of the stove output anyway.

As for soapstone, there is nothing terribly 'magic' about it - sure it's pretty and has a decent balance of specific heat capacity and thermal conductivity - but most stone has similar properties. You could just as easily fill the oven with cheap clay pavers, sand or slabs of rock and not make a huge difference in the heat storage.

 

[szmaine]

Thanks - for the responses.

Well maybe I check it out a bit more unless someone is of the opinion that I don't have much to gain vs the cost/effort.

But I think I could just leave the stone in the stove if it came to it. The is no air coming and going in the oven of an old cook stove - rather the combustion heat from the fire box is diverted by sliding a lever from "kindle" to "oven" and travels in an air space that surrounds the oven compartment. While the stove is a big hunk of iron and holds alot of heat, the fire box is pretty small - like a little box stove- I was hoping to make it hold heat even longer as the fire doesn't last very long without attendance.

 

[pen]

I was hoping to make it hold heat even longer as the fire doesn't last very long without attendance.

And that right there is my concern. It would take a lot of work to get that stone heated up. Basically, "per-fire" you are only going to get "x" amount of BTU's. You have 2 options.

1. They go to the room as the stove was designed.

2. The room warms less as the added thermal mass in the stove is heated but maintains a lower temp longer.


To get something different than these two options, you need to keep attending the fire.

All in all, I think the small firebox is your enemy more than anything else. Now, if you were to keep that cook stove going all sunday I bet the house would stay warmer overnight into Monday with the stone in it than w/out. But without an extended burn in advance of an overnight where the stove will go out regardless you aren't going to gain much unfortunately.

good luck. I wish I had a good cook stove in my home!

pen

 

[SteveKG]

I used an old cookstove for some years. Both the ones I've had were built with the small fireboxes you mention. I tried setting some large pots of water on the top and getting them hot to extend the heating of the room at night [poorly insulated old mine cabin in a cold region]. I didn't do any scientific tests to back up my info', but I don't think it did much good. However, as someone just pointed out, the stove itself is all iron and steel and holds a lot of heat. If it's been burning for some hours, it will stay warm for a long time at night. Obviously, stacking the firebox just before bed will help. But like others, I doubt you will be satisfied by the warmed soapstone.

You could experiment, for free, with any dense stone to test your idea, though. I now have a more modern Rais kitchen stove with oven and use that for baking/heating. It is lined with firebrick and is heavy steel. It remains hot/warm a long time after the fire is burned down, just like my old ones except the firebox on this thing is large and I can load it up to burn all night if I close down the damper some. I do all my bread and other baking in the Rais, and used to do it on the old models, and like it, but the older stoves are a hassle to keep throwing wood in. Plus, they don't take larger wood or larger loads of wood.

Hey, they look great, though.

 

[szmaine]

As I always say every time this comes up...technically yes you'll get more heat - practically, not very much. Even if you can stuff the oven with several hundred pounds of stone and get it up to several hundred degrees, the amount of heat stored is probably only going to amount to 15-30 minutes of the stove output anyway.

As for soapstone, there is nothing terribly 'magic' about it - sure it's pretty and has a decent balance of specific heat capacity and thermal conductivity - but most stone has similar properties. You could just as easily fill the oven with cheap clay pavers, sand or slabs of rock and not make a huge difference in the heat storage.

Hi - I guess I didn't check for more replies before I answered the others, and I see others here agree with you...
Ok, scratch that idea. I guess I was under the impression that soapstone, relative to other types of stone, did indeed have some sort of magical properties...like Magic Heat does - now there's an idea...


kidding, kidding