Breaking bricks

[JR 137]

Are bricks easier or harder to break than concrete pavers, all things being equal?

I'm staring at a stack of bricks that fell from my chimney. I teach middle school science and am contemplating breaking them during class to demonstrate strength of materials, forces, fulcrums, etc.

I'm going to practice a bit so I don't make an *** out of myself, or at least look less stupid. But I think if I successfully broke a brick in front of them with a knife hand strike, they'd probably remember that.
Edit: They've been inside for several months, so moisture shouldn't be an issue. The ones I'll potentially break don't have mortar or anything else on them either, just plain orange bricks. Not the rough kind.

 

[Buka]

Harder.

 

[jobo]

put them on a couple of pencils

 

[JR 137]

Harder.

Thanks. Maybe I'll use a paver instead. Gotta price them. Gotta try breaking one beforehand too. I broke 4 boards the other day, which a few in the dojo said it's about the same as a paver. Even if I broke 6 boards, concrete would mess with my head.

I'm not a big fan of breaking, but why not. And if it'll get my kids to learn something valuable (including DON'T hit bricks ), then all the better. I just have to get comfortable with it before I do it in front of them. And I'll confiscate all phones beforehand so my potential F up doesn't make it onto YouTube.

Edit: Home Depot has pavers for $1.65 a piece. I thought they'd be more, so maybe I'll go that route. Maybe a can of grill lighter fluid and some matches too for more dramatic effect. Ok, maybe I'm getting carried away now.

 

[JR 137]

put them on a couple of pencils

How so?

I'll have a brick on both sides to hold up the brick I'm going to hit. It'll be on a sturdy countertop. And the support bricks will be as far out as possible.

 

[JR 137]

I was also contemplating doing Frank Dux's dim mak with them

 

[jobo]

How so?

I'll have a brick on both sides to hold up the brick I'm going to hit. It'll be on a sturdy countertop. And the support bricks will be as far out as possible.

put a couple of pencils in the middle, put your weight on one,side of the brick and hit the other, it should just break.

alternatively, hold a brick in each hand and bang them together, one or both should break

 

[JR 137]

put a couple of pencils in the middle, put your weight on one,side of the brick and hit the other, it should just break.

alternatively, hold a brick in each hand and bang them together, one or both should break

I thought you that's what you meant with your first paragraph.

As for the second, they already know (or at least should know) that slamming them together will break them.

 

[jobo]

I thought you that's what you meant with your first paragraph.

As for the second, they already know (or at least should know) that slamming them together will break them.

on a more general note, bricks like,pavers have very little,shear strengh, that not what they are designed for. When quality testing they use a crush,strengh test, to see if they are up to standard,
bricks can with,stand,considerable crush forces, but very little in,shear force. I can break a brick in two with only the,slightest of hammer,strikes. Sometimes they break if you drop them 6 inches.
however as a note of caution, fire bricks , like,chimney bricks are made of much tougher,stuff, they have,a,different,clay and,are baked for much longer, so they can resist the expansion and,contraction arising from the heat of your,fire .

breaking them with a lump hammer can be a,challenge , in fact drilling them can be near impossible, so hard is the material. On the other hand, if they have had decades of being warmed and,cool them may just fall apart like they are made of dough, the stress fracture are all ready there.

y

 

[JR 137]

on a more general note, bricks like,pavers have very little,shear strengh, that not what they are designed for. When quality testing they use a crush,strengh test, to see if they are up to standard,
bricks can with,stand,considerable crush forces, but very little in,shear force. I can break a brick in two with only the,slightest of hammer,strikes. Sometimes they break if you drop them 6 inches.
however as a note of caution, fire bricks , like,chimney bricks are made of much tougher,stuff, they have,a,different,clay and,are baked for much longer, so they can resist the expansion and,contraction arising from the heat of your,fire .

breaking them with a lump hammer can be a,challenge , in fact drilling them can be near impossible, so hard is the material. On the other hand, if they have had decades of being warmed and,cool them may just fall apart like they are made of dough, the stress fracture are all ready there.

y

All very good points. Thanks.

 

[Runs With Fire]

I've never heard of anyone breaking actual bricks. The cheap pavers at home depot, like an inch thick, are a cinch. I'm 5'10" and 160#'s and I can brake 10 with 1/4" spacers ie. pencils under each block at the edges. Still working on 12. If you've split 4 pine boards, assuming they were 3/4" x12"x12", you'd definitely have the force output to break 10 pavers. *note* a taller stack requires a longer follow through and a larger weight drop.

 

[Gerry Seymour]

Thanks. Maybe I'll use a paver instead. Gotta price them. Gotta try breaking one beforehand too. I broke 4 boards the other day, which a few in the dojo said it's about the same as a paver. Even if I broke 6 boards, concrete would mess with my head.

I'm not a big fan of breaking, but why not. And if it'll get my kids to learn something valuable (including DON'T hit bricks ), then all the better. I just have to get comfortable with it before I do it in front of them. And I'll confiscate all phones beforehand so my potential F up doesn't make it onto YouTube.

Edit: Home Depot has pavers for $1.65 a piece. I thought they'd be more, so maybe I'll go that route. Maybe a can of grill lighter fluid and some matches too for more dramatic effect. Ok, maybe I'm getting carried away now.

Something tells me getting carried away - at least inside your mind - is not a rare occurrence, JR.

 

[oftheherd1]

I've never done it, nor even tried. Not required nor taught in the Hapkido I learned.

But years ago when I too TKD, boards were broken during demonstrations. I did it once myself. We had a brown belt who told us he had been in Korea and found that the bricks there were different than the ones here. He had liberated a couple of bricks from a construction site. To his consternation, he found bricks here had a higher tensile (whether or not that is the correct term) strength.

But I saw that same guy break a block of granite. He didn't think he could do and said so, and couldn't. Mr. Rhee told him he could, and to do it. He did. I think he was more surprised than those of us watching.

 

[JR 137]

Something tells me getting carried away - at least inside your mind - is not a rare occurrence, JR.

I'm like a squirrel on crack when it comes to thoughts entering my head. I honestly have no idea how I control what comes out as much as I do. It might not seem like it, but very little of it comes out here. I think I get a lot of it out during the school day.

 

[Gerry Seymour]

I'm like a squirrel on crack when it comes to thoughts entering my head. I honestly have no idea how I control what comes out as much as I do. It might not seem like it, but very little of it comes out here. I think I get a lot of it out during the school day.

Sometimes, when I'm delivering a seminar (corporate training), I just stop and share whatever my brain was serving up. I've been known to do that during MA classes, too. I laugh at the oddest moments (like, during dynamic leg stretching), then explain to them why I'm laughing so they don't think I'm crazy ("when we change sides, I feel like I'm dancing in the Thriller video"). Somehow, the explanations don't help.

 

[geezer]

...they already know (or at least should know) that slamming them together will break them.

^^^^Then use that. I did a little self taught breaking just for fun back in the 80s ("self taught" since the art I was studying at the time didn't do breaking). I did take a short course in "soft iron palm" but again, we never tested our progress with breaking.

Anyway, I found it pretty easy to figure out how to break a few concrete pavers with spacers. On the other hand I found standard red bricks and also river rocks to be damn hard ....unless you let the top one raise up a little bit and then slap down against the one below with the strike. That's what Jobo was getting at when he said that they were weak in terms of shear force.

Anyway, now that there's Youtube, I've noticed that this is pretty much the way people who are actually taught to break do it. Or they let the brick hang way over the edge of a hard "anvil" and use leverage to increase the force. And furthermore, as a ceramics teacher, I can tell you that there is a lot you can do to "temper" and weaken bricks.

Now, I'm not saying it doesn't take skill, ...just that it's totally understandable and within the realm of what normal humans can do with practice! Check out how the guy in the following video raises up the edge of the bricks and rocks he breaks to let them slap down on the "anvil" to break them (some of them look like pretty brittle bricks too):

 

[drop bear]

Thanks. Maybe I'll use a paver instead. Gotta price them. Gotta try breaking one beforehand too. I broke 4 boards the other day, which a few in the dojo said it's about the same as a paver. Even if I broke 6 boards, concrete would mess with my head.

I'm not a big fan of breaking, but why not. And if it'll get my kids to learn something valuable (including DON'T hit bricks ), then all the better. I just have to get comfortable with it before I do it in front of them. And I'll confiscate all phones beforehand so my potential F up doesn't make it onto YouTube.

Edit: Home Depot has pavers for $1.65 a piece. I thought they'd be more, so maybe I'll go that route. Maybe a can of grill lighter fluid and some matches too for more dramatic effect. Ok, maybe I'm getting carried away now.

A biker moustache and some rock music should do.

 

[JR 137]

^^^^Then use that. I did a little self taught breaking just for fun back in the 80s ("self taught" since the art I was studying at the time didn't do breaking). I did take a short course in "soft iron palm" but again, we never tested our progress with breaking.

Anyway, I found it pretty easy to figure out how to break a few concrete pavers with spacers. On the other hand I found standard red bricks and also river rocks to be damn hard ....unless you let the top one raise up a little bit and then slap down against the one below with the strike. That's what Jobo was getting at when he said that they were weak in terms of shear force.

Anyway, now that there's Youtube, I've noticed that this is pretty much the way people who are actually taught to break do it. Or they let the brick hang way over the edge of a hard "anvil" and use leverage to increase the force. And furthermore, as a ceramics teacher, I can tell you that there is a lot you can do to "temper" and weaken bricks.

Now, I'm not saying it doesn't take skill, ...just that it's totally understandable and within the realm of what normal humans can do with practice! Check out how the guy in the following video raises up the edge of the bricks and rocks he breaks to let them slap down on the "anvil" to break them (some of them look like pretty brittle bricks too):

Not to take anything away from the guy in the video, because it does take skill...
The bricks he's hitting have holes in them. Some seemed like they broke when they hit the floor.

The ones I'm contemplating hitting are solid and non-porous. Some survived a drop from about 3 stories up. Granted they hit dirt, but the ones he's hitting would probably have shattered.

I'll try to post a pic of the bricks I have. I didn't realize there was that much difference in bricks.

But I'll try the anvil approach. Maybe somehow rig them up on the edge of something and hit them with a hammer first to see if I have any chance.

 

[JR 137]

Maybe I'll do this (with the redneck accent)...

Nah. No tricks.

 

[JR 137]

These are the bricks I'm contemplating breaking...