Rutland Furnace Cement - balooning...

[Alveprins 213]

Alright, so I bought one of these after my horrible clay-mixing and furnace cement experiences...

 

I applied it in a very thin layer to the blade, and let it dry for like... hour and a half. (from my understanding, this can be used right away, and does not actually need to dry for the purpose of differential hardening. Besides, instructions on the tube read "dry for at least an hour".)

 

But to my great surprise the thin layer expanded like a baloon as soon as I moved the knife into the forge... I mean - it was instantly. They blew up to large hollow bubbles on the blade.

 

I saw no other option but to scrape the damn stuff off (which proved quite the challenge btw.) and apply my old refracory cement and steel wire. (I just quenched the blade... no problems. )

 

Anyhow, is this bubbling of the Rutland Black Furnace Cement normal?

 

Sincerely, Alveprins.

[GBrackett 18]

 

I use this version all the time with no issues. I thin it down to pancake batter consistency, apply my base coat, let it dry, apply my build up coat, and then wait a couple of hours before heat treat.

 

Works for me.

 

[Brian Dougherty 1,175]

I use the same stuff you did Alveprins. I let it dry for a couple days, and then heat it slowly. If I don't do this, it swells up as the retained moisture expands.

[Kenon Rain. 15]

I used to slowly bring mine up to temp in a kiln after letting it dry in the sun a bit.

[Gabriel James 90]

ive used the same stuff George posted from right out of the can to HT. and it works great. Ive also thinned down with water substancially to pancake batter and applied and let it sit until the next day..... which also worked out fine.

[Caleb Harris 51]

It bloats up quite a bit for me, first couple of times it was too much, so I just toned it down by thinning the layer a lot. A lot of trial and error in getting your layer thickness right, I think it's one of those things each smith has to refine for himself.

[Caleb Harris 51]

I personally like to apply, then pass in then out of the forge quickly so it doesn't balloon up too fast, and so I can judge if I need to redo it

[Emiliano Carrillo 245]

The last piece I did was a part of a heat treat 'run' done down at Fire and Brimstone. While other pieces were being heated and quenched I was applying my clay, and then as soon as I was done it was thrown in the fire and then quenched. The hamon followed the clay pretty nicely and there wasn't any issue because of the clay ballooning up. So while it can be a little scary, as long as you don't knock it all off while going to quench you should be fine!

[C.Anderson 13]

I find the ballooning of the black Rutland's (as I used to apply it, and as most still apply it) a tiny bit irritating, as it absolutely does change the hamon. It will follow the 'line'...but the effects above and below that line will be different. The 'habuchi' for example, will not be the same as if the clay were dried properly. That said, you shouldn't be using a thick enough layer to balloon much, and if you dry that thin layer in a tempering oven for 30-60 minutes, you'll find the puffing up of the refractory to be pretty much eliminated.

[Alveprins 213]

I find the ballooning of the black Rutland's (as I used to apply it, and as most still apply it) a tiny bit irritating, as it absolutely does change the hamon. It will follow the 'line'...but the effects above and below that line will be different. The 'habuchi' for example, will not be the same as if the clay were dried properly. That said, you shouldn't be using a thick enough layer to balloon much, and if you dry that thin layer in a tempering oven for 30-60 minutes, you'll find the puffing up of the refractory to be pretty much eliminated.

Alright... I'll give it a shot then.

[Riggertrey 1]

Thinning it helps but let dry for hour or so then into oven at 300 deg for 30 min to fully dry. Still some ballooning but not as much

[Alveprins 213]

Thinning it helps but let dry for hour or so then into oven at 300 deg for 30 min to fully dry. Still some ballooning but not as much

I suppose I will do with the Rutlands cement as I do with my Norwegian bought one - put in on top of my heater in my living room, and let it rest there over night. After like 12 hours on that thing - it is completely dried up and hardened.

[Salem Straub 168]

I tried that stuff and I hate it... the ballooning is exasperating. I much prefer satanite and have never had a problem with it. It sticks on just fine without wire or anything.

[Connor J. Myers-Norton 19]

I tried that stuff and I hate it... the ballooning is exasperating. I much prefer satanite and have never had a problem with it. It sticks on just fine without wire or anything.

I've added some red iron oxide and steel fillings to my satinite, it sticks really well and I think the filings bind it together and stop it from cracking. I've also added powdered fire brick to some that I use for added insulation