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Making transparent wood [video] (youtube.com)
89 points by camtarn on Nov 24, 2018 | hide | past | favorite | 28 comments



NileRed mentions this as a shout out to AvE.

I recommend both: AvE has a fantastically interesting folksy veneer hiding deep experience (a joy to watch).

NileRed has a much more polished style, although both are working out of garages.

To see a crossover is greatly appreciated: the core dream of internet mixing and remixing remains alive!


Dead tree carcasses? Sick!


Holy smokes! He cuts(with a lot of torque) towards his unprotected hand with a box cutter. This looks really cool, but that made me cringe.


As AvE would remind him: cut toward your chum, not your thumb.


For anybody watching this who doesn’t know how to use a table saw, he’s lucky he still has all his fingers. I could barely watch that part.


Maybe he ran out of scrap to push with :(. Also: no guard on the saw, blunt as can be and standing to the side instead of in front of the blade. Accident waiting to happen.

It gets worse around 25:45.


Why is it dangerous to stand to the side?


Standing out of the line of the blade is a good thing. Standing all the way around the side of the saw makes it harder to smoothly push through the cut.


Exactly. So the best spot to stand is to the right of the guard and to push with a stick when cutting long wood, and to the left of the blade when cutting sheets, and to make sure they are supported on the near and the far side so the blade doesn't get wedged.


My middle school wood shop teacher rolled over in his grave...


I moved around a lot as a kid, so I saw a lot of wood shop teachers. All were missing various parts of fingers.

Pretty good "mea culpa" video here from a guy that cut his hand up: https://www.youtube.com/watch?v=fifjjacjLBE


I went to school for furniture design in Savannah. None of the teachers were missing any fingers, but plenty of guys from shops in the surrounding area were. From what I recall all of them had lost fingers from jointers and routers, not table saws.

Loosing a digit from a table saw certainly happens, but some of the other tools are less obvious and equally dangerous menaces.


Table saws seem to top the statistics[1][2] though perhaps just because they are so common.

[1] https://www.wwgoa.com/article/shop-accident-statistics-woodw...

[2] https://www.popularwoodworking.com/article/table-saw-injury-...


He's not using a SawStop? That's insane... Promotional video: https://youtu.be/eiYoBbEZwlk


I rather dislike SawStop. It's a destructive system which is very expensive when triggered (whether legitimately or due to wet wood, etc) because it destroys both the stop and the blade. You need to repair your saw before you can continue working. Which is fine if people choose to buy it. But they have been pushing to make their device legally required for all saws, while fighting hard to suppress competing systems, thus removing consumer choice. In particular, they have killed the Bosch Reaxx, which is a non-destructive system that uses inexpensive gas cartridges to instantly drop the blade below the table. If it triggers, reset the blade, drop in a new gas cartridge, and get back to work. Love it. But I can't buy it. Thanks a lot, SawStop.


Sawstop is an innovative company that has some patents. Why wouldn’t they try to use them against a competitor?


If they were just preventing people from making SawStop knockoffs, I'd be fine with it. But they aren't. The Bosch system protects the user through a completely different mechanism. The only thing the two have in common is the sensing of contact with the blade, which is basic physics.

Worse, SawStop is trying to push legislation mandating their system. If they succeed, it would prevent any other system from being developed, even in the absence of patents.

Imagine Microsoft pushing for a law requiring all computers to run Windows. "Why wouldn't they try"? Sure, they can try. And they would be hated for it. As is SawStop.


They would try to use their patents offensively if their mission is to make as much money as possible.

They would encourage manufacturers to adopt some form of safety system, even if it wasn't theirs, if their goal was to keep table saw users safe.

There is some plausible deniability if the competing systems are not as good as theirs - is something better than nothing, or does it create a false sense of security, etc. - but it is pretty clear that Sawstop values profit over the safety of people who can't afford their system.


Yes, it is a company, not a nonprofit or an industry trade group.


I love my sawstop too, but even just using a miter gauge for the crosscut would have been a lot safer. Not to mention a push stick for the rip cut.


The end of the video mentions an application: a composite material made from a renewable resource (wood). The idea would presumably be to get a transparent, strong surface with mechanical properties different from either wood or epoxy alone.

However, the effort to process the wood, and the consumption of non-renewable resources highlight the limitations with this approach. And as was made clear from the video, the process is limited to pieces with thicknesses of a few millimeters at best.

A lot of the problems described in this video arise from the mechanical properties of the wood itself.

So, why not use sawdust instead? Its vast surface to volume ratio means that the resin should penetrate rapidly.

Also, wood-plastic composites are a thing; they're made from sawdust or whole wood:

https://en.wikipedia.org/wiki/Wood-plastic_composite

How such a compsite material could be made transparent is an interesting question with potentially many practical applications.


I think he missed the point that the long cellulose fibers are being filled with resin and then acting as a fiber optic channel, which is why it only works in contact with the page. And why the letters “jump” to the other side of the sample.


I was surprised that he stopped using lengthwise cut pieces. They seemed better suited to compare how easily different methods allow the epoxy could enter the cellulose channels/matrix.


Reproducing my comment from this video: Regarding the short cure time of the epoxy, why not put it in the vacuum with only the resin, and add the hardener only after the ethanol is evaporated?


I've infiltrated porous materials by diluting the epoxy with a miscible solvent and then replacing with less and less dilute solutions until you get just the resin. Commonly done for biological tissue samples for microscopy.


Could you explain this process in more details or link to a more comprehensive description please? Thanks.


Basically the mixture of solvent and epoxy is much less viscous and easily infiltrates the material. There are numerous protocols that describe the process. For example: http://web.path.ox.ac.uk/~bioimaging/bitm/instructions_and_i...

Start where it says "Dehydrate through a series of ethanols or acetones and propylene oxide." basically this is for replacing the water with solvents, if the sample is dry you can just immerse it in your solvent of choice, probably propylene oxide (toxic) or acetonitrile (less toxic), something miscible with your epoxy resin.

Follow the protocol up to the polymerization. I'm not sure if all resins are suitable for this type of infiltration but there are many suitable ones, see: https://www.tedpella.com/chemical_html/chem2.htm


The hardener would need to get into the crevices too, which would be difficult (especially since the vacuum insertion would no longer work, and it would harden near the surface before you'd have enough time for a good mix).




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