Cleaning excess mortar from inside of dome

[fremen325]

I have been trying to clean up mortar as I lay a course of brick. All the big glops and smears are gone BUT I still have a very thin layer of mortar (heat stop) on the face of the bricks in some areas. My rag was apparently too dirty and didnt do a good enough cleaning job.

Other than using the grinder, does anyone have any tips on how to remove the thin layer of mortar from the brick faces? I tried heavy sandpaper but that barely did a thing.

[Les]

Re: Cleaning excess mortar from inside of dome

Use a muriatic acid solution, start with 50/50 ( acid to water). Avoid breathing the vapors because it is NASTY stuff and wear rubber gloves, long sleeves, and safety glasses if there is a chance of the stuff splattering around. If you get to the mortar fairly fast it does a great job of dissolving the mortar.

[fremen325]

Re: Cleaning excess mortar from inside of dome

Thanks Les! You made the muriatic acid sufficiently scary sounding so I tried an orbital sander instead (I also have a sander so didnt have to buy something else). I used a P40 grit (very coarse) pad and it worked really well. As a side benefit, I think I have remove all the loose mortar bits that might flake off into my pizzas. If anyone else is reading this and thinking of using the sander to remove excess mortar, be sure you wear a dust mask and I did a full goggle mask for the eyes as the sander was throwing quite a bit of refractory mortar dust which isnt good to for your lungs and stings when it gets in the eyes.

[Tscarborough]

Re: Cleaning excess mortar from inside of dome

I would add that if you are going to use muriatic acid, the first thing you need to do before cleaning is thoroughly soak the brick before the application of the acid solution. You do not want the solution to be absorbed into the brick (firebrick have a high absorption level), so they need to be saturated. Obviously this will all need to be removed before hard firing.


(50/50 is very dangerous, 10 water to 1 muriatic acid is sufficient. Muriatic is itself a 30% +/- solution of hydrochloric acid, nasty stuff)

[fremen325]

Re: Cleaning excess mortar from inside of dome

Here are some before and after photos of the interior after using the orbital sander. The after photo includes the next course so it will need some cleaning up as well.

[Les]

Re: Cleaning excess mortar from inside of dome

I would add that if you are going to use muriatic acid, the first thing you need to do before cleaning is thoroughly soak the brick before the application of the acid solution. You do not want the solution to be absorbed into the brick (firebrick have a high absorption level), so they need to be saturated. Obviously this will all need to be removed before hard firing.


(50/50 is very dangerous, 10 water to 1 muriatic acid is sufficient. Muriatic is itself a 30% +/- solution of hydrochloric acid, nasty stuff)

I have found that 50/50 works quite well. The less time I spend screwing around with the stuff, the better. And you are correct - it is nasty!

[Aquaponicsguru]

For those that have laid ceramic tile, they know that the best way to clean the mortar (or grout when laying tile) is to use clean sponges and several buckets of clean water after the mortar (grout) sets up a bit. Have the buckets ready and as the water gets dirty rinsing the sponges out, change buckets. You have to do this as you lay the firebricks and you can't let the mortar harden too much as that will make it more difficult to remove. I usually clean them after each chain or when the mortar has set up sufficiently. You also don't want to do it too early either because you will weaken the mortar with excess water before it has a chance to stick the bricks together. I have been doing this as I go and it seems to be working well. However, I'm sure the last few chains will be more difficult as the opening gets smaller. I'm on my sixth chain now. I'm sure when I close the dome, there will be some cleanup at the top but hopefully not too much. The key is to keep your sponges as clean as possible so very little mortar residue, if any, is left on the brick surfaces.

[Les]

The key is to keep your sponges as clean as possible so very little mortar residue, if any, is left on the brick surfaces.

The key is to not use mortar on the inside of the oven

[Aquaponicsguru]

Yes...in a perfect world..

[dakzaag]

Perhaps an even more relevant key is the fact that this is the inside surface of a black oven...After a few Pizza parties, you will realize that the surface gets plastered with soot at every firing. Nothing says "I have so much time to waste" like obsessing about mortar smudges in a black oven. But that is just the way I see things thru the oven vent opening.

[joeykramer]

bringing up an old topic. while i am not too concerned about the oven walls, i am concerned about the mortar build up on the floor of my oven. i used cardboard to cover the floor, but it was not perfect and some has gotten onto the floor. some large clumps, which i will knock off, but there seems to be a film on top of many of my floor bricks. is it worth trying to sand them down? replace as many as i can? or leave them and the fires will clean it up just fine? i am not interested in using acid. thanks for the help

Joe

[Saluki]

Joe,

Easiest solution I found to cleaning up excess mortar is to take a sliver of firevrick,and use it as sandpaper. This works great for cleaning up,joints as well as floor bricks.