How to test homebrew mortar

[pluscwc]

I'm going to use the 3:1:1:1 recipe for home-brew. I'd like to know that my technique works before building too much. How should I test it?

So far I mortared in maybe 1/3 of my soldier course plus two test bricks. How long to wait before trying them out to see it it holds well? The mortar seems pretty crumbly. I'm using white portland that I have sitting around, and some fine sand I picked up a HD for a concrete leaf mold project.

Any tips? I'm spraying the surfaces of dryish bricks to wet them, then buttering with mortar the spreadability of peanut butter. And squishing the bricks together to try to get it to bond.

Should I cover with damp burlap? For those of you who never did brickwork before, what do you wish you had known at the beginning?

[mrchipster]

Re: How to test homebrew mortar

I'm going to use the 3:1:1:1 recipe for home-brew. I'd like to know that my technique works before building too much. How should I test it?

So far I mortared in maybe 1/3 of my soldier course plus two test bricks. How long to wait before trying them out to see it it holds well? The mortar seems pretty crumbly. I'm using white portland that I have sitting around, and some fine sand I picked up a HD for a concrete leaf mold project.

Any tips? I'm spraying the surfaces of dryish bricks to wet them, then buttering with mortar the spreadability of peanut butter. And squishing the bricks together to try to get it to bond.

Should I cover with damp burlap? For those of you who never did brickwork before, what do you wish you had known at the beginning?

If the portland was laying around for more than 6 months go and spend 6 bucks and get new. It can go off with moisture in the air and it is not worth the risk.

Wish I knew to mix real small batches
Build from inner arch brick first.
Get a nice looking joint spacing at back of oven that is what people will see
Use the reaching arch technique see Octoforno.
Build a brick cutting jig. See my post on this
Buy a 10 inch or larger brick saw. Harbor freight.
Create an Indespensible tool and use it.
Use thin fabric rubber coated gloves
Keep the top of all bricks pointed at the center of the oven
Plan for a 1 inch reveal on the inner arch.
Insulate the floor with at least 4 inches of good insulation.
Place you first brick on the next course up at the end of the working day so it is solidly set for the next days work.
Calculate and cut all of the bricks needed for the current course before resetting for the next course.
Build the inner arch first and make sure the reveal is almost perfectly square to the floor and as flat as possible. Build a flange on the arch form to guarantee the location of the bricks of the inner arch.

[Tscarborough]

Re: How to test homebrew mortar

I tested it by bonding small pieces of firebrick together and then throwing them in a hot fire. Not a fair test of bond strength, but I was checking for degradation of the mortar.

[brickie in oz]

Re: How to test homebrew mortar

For those of you who never did brickwork before, what do you wish you had known at the beginning?

The pay is lousy, your back will give out and people will cheat you......

[pluscwc]

Re: How to test homebrew mortar

I got a new bag of portland, it seems a bit better, still some bonds failed, I think due to jostling after the bricks had sucked some of the moisture out. Mortared the soldiers tonight with wetter mix, hopefully it will all hold. Chipping it off was easy but tedious.

I'll try to follow your tips. I already built a brick cutting jig in Chip's style. Deejayoh updated his spreadsheet to accommodate it.

[brickie in oz]

Re: How to test homebrew mortar

still some bonds failed, I think due to jostling after the bricks had sucked some of the moisture out.

Thatll do it, once the bond is broken the brick should/needs to relaid.