Can of worm alert....

[FyreBug]

Sorry about this folks, but there was a heated debate a while back regarding pumice bricks vs. heavy silicate bricks to line up the fire chamber.

Some folks contented that pumice (light weight) bricks were far superior in efficiency and would provide the best performances.

As a manufacturer who use various material including the above I maintained it did not make a big difference and hence the can of worm and hot debate. I maintained that if it made such a big difference why would not all MFG use the light weight? Unfortunately I did not have the numbers to back me up then.

Firstly, those advocating light weight bricks were right and ... wrong. Pumice bricks do have better insulating performance than heavy duty brick due to the amount of air in them.

However, Our own internal testings between various material shows it hardly makes a difference between these 2 bricks on wall & floor of the fire chamber.

Where it really makes a difference is in the baffle area. So there...

While I'd love to share the hard data, it is proprietary so you'll just have to take my word for it.

 

[NW Walker]

Not to nitpick, but you really should qualify that statement as being specific to your stove design, rather than comprehensive for all stoves. In some designs, the difference is great, and the entire firebox being insulated is crucial. Heavy bricks will hurt performance significantly in some designs. I think that rather than it being a case of better or worse, it's just a simple matter of different properties in the different bricks, and using the right one for your application.

 

[begreen]

If this were universally true you would never see skamol in a stove.

 

[FyreBug]

Not to nitpick, but you really should qualify that statement as being specific to your stove design, rather than comprehensive for all stoves. In some designs, the difference is great, and the entire firebox being insulated is crucial. Heavy bricks will hurt performance significantly in some designs. I think that rather than it being a case of better or worse, it's just a simple matter of different properties in the different bricks, and using the right one for your application.

Hence the can of worms...

A plate steel wood stove between models and MFG are inherently the same. They are square boxes made of metal and bricks. Truly as far as design is concerned you cannot get simpler. Where design truly makes a difference is in air flow and tweaks where combustion occurs.

Materials being the same, Laws of physics (conduction, convection) will apply similarly.

 

[FyreBug]

If this were universally true you would never see skamol in a stove.

Did not say skamol which we use as well. We're comparing between bricks.

 

[BobUrban]

and there is the DBL edge sword so to speak of OVER insulation. You can insulate a forge that gets internal temps to 2500+ and the outside can be touched with your bare hand. Great for forge welding damascus steel but does not offer much convection into the room when you want to heat the space it sits in. So you can insulate too well. Sure you get extream internal temps and long burn cycles but no heat. I will stick with the harder bricks because I would tear up the softies to fast.

Not an engineer and no "real" science in my testing process but I will say that without doubt - the pumace bricks insulate better in my forge than the hard ones but my rake and shovel would eat them for lunch in my NC30. Other stoves may work differently and therefore require the pumace.

My 2cents

 

[rijim]

No can of worms, use the product reccomended by the manufacture for your particular stove. End of story.

 

[corey21]

No can of worms, use the product reccomended by the manufacture for your particular stove. End of story.

There be the answer to this thread.

 

[Bub381]

Ayuh! but we appreciate the help.

 

[Jags]

Hey, I am all for full info

Pumice bricks do have better insulating performance than heavy duty brick due to the amount of air in them.

Is / was the only part that I needed to read. As I have said before...ya can't go wrong with installing what the mfg's used for your stove.