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Crushed wood is stronger than steel

nature.com

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Re: Crushed wood is stronger than steel

#71

Post by fiddlerwoaroof »

dghughes wrote: post #68
cdsboy wrote: post #57

Earlier quoted context omitted.

Doesn't having a cutting board as hard as stone defeat the purpose of having a cutting board?

Isn't the point of a cutting board to protect the counter top from the knife, mobility (move chopped food to another location) and being easy to clean? As opposed to a flat counter top which can get marred with marks, can't move, can be cleaned but not thrown in a sink.

They also protect the knife blade from damage: if you were to cut directly on stone, the knife hitting the stone would cause it to dull more quickly.

Re: Crushed wood is stronger than steel

#72

Post by tonyarkles »

dghughes wrote: post #68
cdsboy wrote: post #57

Earlier quoted context omitted.

Doesn't having a cutting board as hard as stone defeat the purpose of having a cutting board?

Isn't the point of a cutting board to protect the counter top from the knife, mobility (move chopped food to another location) and being easy to clean? As opposed to a flat counter top which can get marred with marks, can't move, can be cleaned but not thrown in a sink.

Also to provide a less damaging surface for the knife blade.

Re: Crushed wood is stronger than steel

#73

Post by keevie »

dghughes wrote: post #68
cdsboy wrote: post #57

Earlier quoted context omitted.

Doesn't having a cutting board as hard as stone defeat the purpose of having a cutting board?

Isn't the point of a cutting board to protect the counter top from the knife, mobility (move chopped food to another location) and being easy to clean? As opposed to a flat counter top which can get marred with marks, can't move, can be cleaned but not thrown in a sink.

I'd say a much more important purpose of a cutting board is to protect the edge of your knife. If you hit the edge of your knife on something really hard, it'll chip, or fold--basically just ruin it. This might not be such a big deal for home cooks with super dull knives (after all, glass cutting boards still exist for some reason!) but for a professional I'd think a cutting board that destroys your knives would be worse than useless.

Re: Crushed wood is stronger than steel

#74

Post by dkarl »

bpyne wrote: post #55
jacquesm wrote: post #6

The most expensive wooden floors have the end grain exposed facing upwards and this is then compressed down, much like the top of a good quality butchers block. Those floors are just about indestructible. The heavier such floors are used the stronger they get! The wood in the article is compressed crosswise to the grain (so they get thinner rather than shorter), using the original planks as the raw organic material t…

Sorry to go on a tangent, but your comment reminded me of a book I read about the Chinese culinary culture pre-revolution. Chinese chefs had, and may still have, wooden cutting boards that were conditioned somehow such that they were as hard as stone. (There was also an implication that they resisted bacteria unlike normal wood boards when not scoured properly.) These boards were passed down from generation to genera…

You'd destroy your knives/cleavers with a stone cutting board. The wood needs to give a little bit so the blade doesn't chip and holds an edge long enough to be useful. Sounds like pop writing sensationalism, as with Damascus steel, which TV shows imply (or outright state if they have no shame) is better than any steel we currently know how to make.

Re: Crushed wood is stronger than steel

#75

Post by jacquesm »

bpyne wrote: post #55
jacquesm wrote: post #6

The most expensive wooden floors have the end grain exposed facing upwards and this is then compressed down, much like the top of a good quality butchers block. Those floors are just about indestructible. The heavier such floors are used the stronger they get! The wood in the article is compressed crosswise to the grain (so they get thinner rather than shorter), using the original planks as the raw organic material t…

Sorry to go on a tangent, but your comment reminded me of a book I read about the Chinese culinary culture pre-revolution. Chinese chefs had, and may still have, wooden cutting boards that were conditioned somehow such that they were as hard as stone. (There was also an implication that they resisted bacteria unlike normal wood boards when not scoured properly.) These boards were passed down from generation to genera…

Hard as stone is probably meant in a figurative sense, not a literal sense. End-grain wood is pretty hard, especially when compressed (for instance: by beating it with a hammer), but it is nowhere near as hard as stone. That said, there are some pretty soft stones :)

I've broken more than one high quality steel bit on various kinds of wood, but that's usually not a measure of how hard the wood is but how much friction there is between the drill and the wood and how much of the drill bit is inside the wood. If the wood were really hard you would not be able to enter the bit at all and it would never break but just sit there spinning on the surface.

Finally, the whole trick to a cutting board is that end grain wood will wear very little and the knife will be sharp much longer specifically because it is not as hard as stone.

Re: Crushed wood is stronger than steel

#76

Post by logfromblammo »

willvarfar wrote: post #19

People may also find Pykrete interesting https://en.wikipedia.org/wiki/Pykrete Its adding wood pulp to ice to make the ice much much tougher. It was invented by the epitome boffin Geoffrey Pyke, who proposed they build an aircraft carrier of it! https://en.wikipedia.org/wiki/Project_Habakkuk

Did you mean to say "eponymic" instead of "epitome"?

Re: Crushed wood is stronger than steel

#77

Post by jacquesm »

nck4222 wrote: post #37
jacquesm wrote: post #6

The most expensive wooden floors have the end grain exposed facing upwards and this is then compressed down, much like the top of a good quality butchers block. Those floors are just about indestructible. The heavier such floors are used the stronger they get! The wood in the article is compressed crosswise to the grain (so they get thinner rather than shorter), using the original planks as the raw organic material t…

>making it effectively thinner, lighter and stronger at the same time. The article never says it's lighter, and the paper is behind a paywall. Interesting process none the less.

It does say it is lighter, it says it removes certain compounds from the wood and then compresses the remainder without further additives. So it is lighter than the original wood but much more dense.

Re: Crushed wood is stronger than steel

#78

Post by bobf »

dsfyu404ed wrote: post #70
burger_moon wrote: post #61

Earlier quoted context omitted.

This used to be very common for machine shops to have wood floors, I found an article detailing it with some pictures. I worked in a couple shops that had wood floors, they were nothing to look at, it was an industrial setting after all. https://web.pa.msu.edu/services/machine-shop/shopfloor.htm At Amazon in the new Day 1 building their main staircase to the lobby is built from wood ends and it is done very nicely. I…

>This used to be very common for machine shops to have wood floors That is done because wood is soft and if you drop a tool or part on the floor it's far less likely to be damaged. Wood has been superseded by (usually vinyl IIRC) tile and/or rubber/plastic mats in a lot of places.

It's also done for the comfort of the people working there. Standing on concrete all day is more tiring than on a wooden floor.

Re: Crushed wood is stronger than steel

#79

Post by MrLeap »

masklinn wrote: post #36
baud147258 wrote: post #26

Earlier quoted context omitted.

When the steel is inside concrete (in case of reinforced concrete), doesn't the concrete protect the steel? And since it's how most steel is used in construction, doesn't steel has an advantage here?

Concrete does provide some form of insulation as it has a fairly low rate of heat transfer. At the end of the day it'll still heat up though, and it's that heating up which weakens the steel, direct contact is not a requirement (there are specific methods like insulated concrete form which have higher fire resistance).

I have a technique I'd use to add heat resistance to steel.

Only necessary If we lived in a doomed world where engineers didn't exist and I was asked to make steel more heat resistant.

Cover steel beams in a relatively thick later of plaster of paris mixed with very find grain sand.

I built a charcoal forge out of that material (I used quartz sand I got from a pool supply store) and it's ludicrously heat resistant. It's lined with 4mm of aluminum (melting point 660°C) and the plastersand layer is about 25mm thick. I can melt steel bar above it without causing any visual changes in the aluminum body. I've used it about 20 times in the last year. Lots of spalling on the plaster layer but for most architectural applications I doubt you need to have a blower fueled inferno happen > 2 times a week during the summer.

I wager real engineers have more cost effective, data driven solutions. Just thought it was a neat fact.

Re: Crushed wood is stronger than steel

#80

Post by tbirrell »

cdsboy wrote: post #57
bpyne wrote: post #55

Earlier quoted context omitted.

Sorry to go on a tangent, but your comment reminded me of a book I read about the Chinese culinary culture pre-revolution. Chinese chefs had, and may still have, wooden cutting boards that were conditioned somehow such that they were as hard as stone. (There was also an implication that they resisted bacteria unlike normal wood boards when not scoured properly.) These boards were passed down from generation to genera…

Doesn't having a cutting board as hard as stone defeat the purpose of having a cutting board?

The purpose of a cutting board is to protect the things underneath it that are not as hard as stone.
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