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Making Bulletproof Wood [video]

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Re: Making Bulletproof Wood [video]

#31

Post by mcpackieh »

beAbU wrote: post #16
spacebacon wrote: post #8

Earlier quoted context omitted.

From my experience shooting plywood, the 9mm would have no problem going through the same thickness. He is legitimately on to something with his process.

What are you on about. 45cm is INCREDIBLY thick, and a solid plywood block of that thickness will probably stop high caliber rifle bullets. I've used telephone books as backstops in the past and abour 3-4 of them is enough to stop a handgun bullet easily. We use 10mm mild steel plates for targets, and they don't even dent when shot with a 9mm round.

What are anybody in this thread on about with 45 centimeters? He stopped a 9mm with about four cenitmeters. Skip to 53:00

Re: Making Bulletproof Wood [video]

#32

Post by blamazon »

dylan604 wrote: post #30
blamazon wrote: post #26

Regarding the interior of the wood not being soaked by the stuff when it was cut open. (35:32) I suspect moisture content of the wood is a factor. A similar challenge is faced when cooking French toast, with particularly thick slices of bread. When making French toast, you want the custard to fully soak the bread, but a similar effect occurs if you use moist bread, where the middle is not soaked as well as the outsid…

are you using the whole egg or just the yolk for the custard?

Either works - adding only yolks yields a richer custard I think, but it's my belief that the albumen carries some important quality to the end product - somewhat mysterious, but anyway I usually use the whole egg. I sometimes throw an additional yolk or three in there if I'm feeling luxurious, exactness is not key to the ratios. If you mix the custard the night before too it develops a lovely flavor profile by morning.

Re: Making Bulletproof Wood [video]

#33

Post by mcpackieh »

gambiting wrote: post #12
spacebacon wrote: post #8

Earlier quoted context omitted.

From my experience shooting plywood, the 9mm would have no problem going through the same thickness. He is legitimately on to something with his process.

A 9mm would get through 45 centimetres of plywood???

Nilered didn't use 45 centimeters of densified wood, he used maybe four centimeters of it.

Re: Making Bulletproof Wood [video]

#34

Post by wongarsu »

curiousgeorgio wrote: post #7

There are two potential issues that I wish he either explored or explained in more detail: 1. When he cut the post-treated wood and the middle looked very much like untreated wood. He kind of glossed over that and explained that he thought the chemicals were penetrating all the wood, but that shot looked really suspicious. I’d be surprised if the chemicals were really effective for that thick of a piece with only one…

I suspect the benefit of the multiple layers was mostly from the different grain orientations stopping the splintering. I agree that more layers of thinner boards would have performed better, but I'd wager this would hold true even for the weakest of glues, or no glue at all.

Re: Making Bulletproof Wood [video]

#35

Post by wongarsu »

tromp wrote: post #14

That's some amazing amount of effort! I was hoping to see him contact the authors of the paper to get their comments on his methods, and in particular on the seemingly incomplete chemical treatment shown in the cut block. He could try starting with e.g. 3x thinner blocks to ensure chemical treatment reaches the core, and then glue 3 of those together to end up with the same thickness as his single layer. Curious to s…

He even mentions that the paper found that treating the wood for longer lead to worse results. That combined with the incomplete treatment of the middle leaves me suspicious how much the chemical treatment really contributes, compared to just compressing and heating wet wood.

Re: Making Bulletproof Wood [video]

#36

Post by mondocat »

It seems there was a conflation of two expectations. The first being a material so hard that bullets just bounced off of it. The second being a material so effective at dispersing energy that bullets could not penetrate it. Kevlar is the well known example of the second category. In the end, the compressed wood seemed to improve a little in both categories, but not much. For reference from the video the same bullet that was stopped by 7 untreated boards of wood only required 3 treated pieces.

Re: Making Bulletproof Wood [video]

#37

Post by langsoul-com »

A_D_E_P_T wrote: post #23

I hate to rain on his parade, but as a bulletproof material that stuff is effectively worthless. An equal density of plain transparent polycarbonate has substantially more ballistic resistance, and is far easier to make and mold to shape. The same can be said for equal densities of steel, aluminum, magnesium, titanium, etc. However... As a material for musical instrument construction, that hyper-densified wood might…

It was never about practicality, it's more about the interest and whether it can be done.

Otherwise just go buy a normal bulletproof vest and be done

Re: Making Bulletproof Wood [video]

#38

Post by itronitron »

blamazon wrote: post #26

Regarding the interior of the wood not being soaked by the stuff when it was cut open. (35:32) I suspect moisture content of the wood is a factor. A similar challenge is faced when cooking French toast, with particularly thick slices of bread. When making French toast, you want the custard to fully soak the bread, but a similar effect occurs if you use moist bread, where the middle is not soaked as well as the outsid…

You can also skip the searing in a pan step and just bake all of the soaked slices in a casserole dish in the oven for bread pudding :)

Re: Making Bulletproof Wood [video]

#40

Post by gambiting »

mcpackieh wrote: post #31
beAbU wrote: post #16

Earlier quoted context omitted.

What are you on about. 45cm is INCREDIBLY thick, and a solid plywood block of that thickness will probably stop high caliber rifle bullets. I've used telephone books as backstops in the past and abour 3-4 of them is enough to stop a handgun bullet easily. We use 10mm mild steel plates for targets, and they don't even dent when shot with a 9mm round.

What are anybody in this thread on about with 45 centimeters? He stopped a 9mm with about four cenitmeters. Skip to 53:00

You are literally replying to a comment thread where OP said [about plywood] "While not suitable as personal armor due to thickness (generally around 1.5ft/45cm)"

Did you skip that entire part of the conversation and just went to the final comment in the tree?

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