How many Coats of Satanite to High Temperature Wool

The wool gets mighty well toasted by the furnace. Well, strictly speaking there might be a difference in being pre-toasted with an O/A torch hot gases and simply being cooked in the furnace hot gases. I guess I would be very surprised if there were a major difference given that both involve carbon-rich fuels at high temp, oxygen at high temp, and fairly high velocity of those gases. That coupled with the fact that very recently exposed (late flaking areas) looked a good deal like toasted areas. But, who knows without trying? I guess I am so happy with the protection Satanite is giving and so impressed by the unprotected breakdown, that I am not too crazy about doing that test. But, for real science it should be checked.

Denis

 

Yes, from the looks of the O/A toasted surface, at least the way I did it, that surface is not smoothly gassified. There are globs of alumina sitting on a fibrous surface of PARTIALLY coalesced fibers. In the furnace damaged areas there are indeed small areas of glass maybe one square inch or so in size or so. But, some of those areas are deeply eroded and don’t seem protected. My impression was once started glassification promoted more glassification analogous to getting that metal puddle estabished when flame-cutting steel or welding.

Drnis

 

Glad the Satanite seems to protect the toasted surface. It is hard to understand why the toasted wool does not go ahead and melt during subsequent heats. I guess time will tell.

 

It is hard to understand these materials---ceramic wools, Satanite etc. They are complex mixtures of substances that are themselves complex. For instance, Satanite contains significant amounts of Kyanite. According to the minimal reading I have done on that mineral it does some interesting things on exposure to heat. https://en.wikipedia.org/wiki/Kyanite

And then there is ceramic wool. Evidently materials scientists are still at a loss to fully understand how kaolin,just one of its components, though it is a very common mineral, forms naturally given the assumed conditions under which it is thought to have been deposited in the earth's crust.

Now combine the mixture Satanite with the mixture ceramic wool, apply heat and a highly reactive atmosphere and then just try to reason out in our heads what will happen. It ain't simple.

Now, all of my above BSing aside, I have no way to know how well the toasted ceramic wool coated with a thin layer of Satanite will hold up. However, FishBonz says he has had good results with his Satanite/wool lid and my very limited experience is encouraging. Might as well give it a whirl and find out. I agree that time will tell. The nice thing is that if it does not work out, not much is lost. If it does work out, I'll be surprised and very happy.

Denis

 

Satanite MSDS

https://thinkhwi.com/safety-data-sheets/

 

Notice they have "several" products.

 

Well today I am installing my extended chimney liner an a renewed 2nd layer of 2600F Cerachem insulating wool in my lid. As reported above, after 5 heats or so, the wool started to fail at its exposed edge at the opening of the chimney. I think this was because my previous chimney liner only extended 1" under the steel top of the furnace lid thus leaving exposed the edge of the wool save for a thin coating of Satanite. The new liner has a 2.25" tube extending down into the furnace below its rim that sits on the top of the furnace lid. That does protect the approximately 2" of wool that lines the lid on my 30-gallon drum very low mass furnace. I did put some rigidizer on the first layer of wool and on the second layer and I did toast the wool of the second (exposed) layer of wool prior to applying a thin coat of Satanite.

And I did include a "control joint" in the chimney liner as it seems that rings of castable end up cracking no matter what. So, I'm hoping this will prevent more random cracks. Again, time will tell.

If the foot of snow we have now will melt in the next few days, I am anxious to fire up the furnace.