MDF is currently glued together with something containing formaldehyde which makes it dangerous to burn and presumably also quite harmful to saw without inhaling. At the same time, there are perfectly nice bits of real wood hanging about which it seems a waste to set fire to but aren't big enough to use to make furniture, planks or daleks, and there are also trees which produce nice resins. Why not put the two together and make nice fibreboard?
Get some scraps of wood you can't use structurally, chip them then soak them in molten resin from an actual tree before pressing them into boards. The result (provided the resin isn't thermosetting) could be a versatile wood- like structural material without an appreciable grain which could also be burnt fairly safely. You could also strengthen joints made with it by heating, thereby melting bits of resin together, or mould "wooden" pieces.-- nineteenthly, Dec 13 2009 the resin isn't the thing that's holding wood together.-- FlyingToaster, Dec 13 2009 Not when it's alive. The idea is to take some sawdust and soak it in resin. Lignin sticks lumps of wood together. I'm suggesting that resin is used to cause particles of wood to stick together.-- nineteenthly, Dec 13 2009 I dunno. Resin is very brittle.
Also, why do you expect burning resin to be any less harmfull than burning man-made glues? Bubonic plague is natural too, after all.-- MaxwellBuchanan, Dec 13 2009 //Bubonic plague is natural too, after all.// Yes, but it makes a poor substitute for wood.-- xenzag, Dec 13 2009 It would be used to stick the wood together, not replace it, [xen]-- pocmloc, Dec 13 2009 formaldehyde-free MDF is available. Not sure how great whatever else in there is, though.-- oxen crossing, Dec 13 2009 You know what's a major carcinogen? Creosote. You know, pine sap. Natural does not equal safe, especially if you're heating and cooling it repeatedly.-- MechE, Dec 14 2009 I'm aware that creosote is carcinogenic. That's _one_ resin. It doesn't follow that all resins are carcinogenic, for instance myrrh and rosin. I'm not suggesting burning it, just melting it. Creosote is not generally from conifers in any case, but chaparral (which i don't use in case you were curious) and Betula, sorry, Fagus, or from coal tar.
The point of it being part of the biosphere is nothing to do with it being healthy, it's about approaching carbon-neutrality and avoiding the introduction of compounds which are likely to accumulate because they don't get metabolised.-- nineteenthly, Dec 14 2009 There are already hundreds of pressed board forumulations that have been experimented with. It's unlikely that much that is obvious has escaped the attentions of waste-recycling-for-profit in the building materials industry. Not to say that some fantastic, and very 'green' method will not be announced tomorrow; but what you've described is almost certain to have been attempted by now.-- outloud, Dec 14 2009 Natural resin : not going to pass flammability standards. Your house would burn like an E-Z LITE fire starting stick.-- WcW, Dec 14 2009 Lots of people seem to think that we stick shit together for sticky-ness. This is not true! Sticky-ness was solved a long time ago. We stick shit together for other reasons. Chief amongst those reasons is flame retardation. Why formaldehyde?Becuase it don't react! Well organically, anyway.
You want to make a friendly chipbaoard? Paint a fucking smiley face on the existing one...-- 4whom, Dec 14 2009 bwouo man! fushazazle on de boaord be wik'ed cou!-- WcW, Dec 14 2009 Booyakhasha! C to the H2 the izzo!-- 4whom, Dec 14 2009 // [M-D-F] recipe. bigsleep, Dec 13 // An idea crying out for this annotation - from the first sentence.-- gnomethang, Dec 14 2009 But i want it to burn well. Right now, i can't burn the MDF because it's not safe to do so. This stuff would go up like a firework. And [gnomethang], amazingly i didn't think of that at first.
Safety is overrated. I want asbestos sandwiches.-- nineteenthly, Dec 14 2009 //It doesn't follow that all resins are carcinogenic//
Actually, it does - more or less. Most organic gloop is carcinogenic when burned. Why? Because any organic gloop contains a bunch of complex (often aromatic) carbon compounds, which break down in all kinds of complex ways when heated (which also happens when sawing).
The worst effects happen when the stuff is burned at relatively low temperatures, or with inadequate oxygen. Under these circumstances, just about everything from coal to wood is carcinogenic, roughly to the same degree.
If you want to design a non-carcinogenic-when-burned glue, you would avoid natural products like the plague. At least with synthetics you have a chance of finding something simple whose breakdown products you can understand and whose combustion yields relatively few carcinogens.
[-] because this idea is based on a romantic misconception that nature actually gives a shit.-- MaxwellBuchanan, Dec 14 2009 Thanks Max. It's nice to learn something new. On a somewhat related matter, I recently wondered how it is that silica dust could result in silicosis when cowhands, sheep herders, Arab nomads, invading Huns, etc, etc, have been gulping lungfulls of silica dust for since, well forever.
The diference, I discovered, is how the grains are broken down. Our lungs have adapted to the vast majority of silica dust on the planet because it it microscopically pretty smooth. We just cough up a little mud. No harm done.
The dangerous variety is generally 'man made' by saws, chisels, crushers, blasters that fracture the grain rather than wear it smooth. It was hard to get siicosis in the old days using just a hammer and chisel, but still possible. It's just a lot easier today with powertools. This dust is microscopically jagged. It's difficult to dislodge from the lungs and tends to tear things up. It's exactly the difference between a shard of broken bottle on the beach that has been there for fifty years, or was just broken yesterday. Only the latter is likely to ruin your day.-- outloud, Dec 14 2009 And thanks to you, also, outloud - I too have acquisited new information, and am gluternaturally pleased.-- MaxwellBuchanan, Dec 14 2009 random, halfbakery