DIY, craft, materials, and such / Household and DIY substances

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Glues and sealants

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)

Wood glue, white glue, carpenter's glue, school glue and Elmer's glue (in the US), is based on polyvinyl acetate (PVA)

while PVA is the main ingredient, products vary in additives, so will vary in viscosity, strength, odor, and such
useful for porous materials
is slightly flexible itself
is nicer to paper and cloth than many other glues (polymer or otherwise), because it is non-acidic, or only mildly (just enough to help drive the reaction)
pretty cheap per volume


Superglue, crazy glue and a few other product names is typically cyanoacrylate, which is fast and works on quite a few types of surface (e.g. practical enough to use on metal). Note that it reacts exothermically with cotton so is typically a bad idea to let near clothing.

There are a few accelerants, some of which are very cheap and simple (such as baking soda, and steam), and some fancier chemical ones that will often make it be thinner, and dry more cleanly.

(cleaner seems to mean reacting faster, which gives it less time to vaporize and react with airborne moisture - which seems the main reason you frequently get a white-ish sheen near drying CA)



'Epoxy' is a general term, and can apply to many variations, most of which are thermosetting polymers that cure when mixed with a catalyst, and generally then very solid. As a result, it works as a glue on anything it sticks to. Also used by itself e.g. as floors or floor coatings, as it has a fairly durable surface.

https://en.wikipedia.org/wiki/Epoxy#Adhesives


Polyurethane is also used as a water resistant glue,

used in things like woodworking and bookbinding
https://en.wikipedia.org/wiki/List_of_polyurethane_applications#Adhesives


Names involving 'cement' are often vague:

'Rubber cement' could refer fairly generally to polymers, though is regularly latex mixed with a solvent(verify)). The drying process is actually the evaporation of the solvent, leaving the somewhat flexible polymer behind.


Plastic cement can refer to:

a specific cement (in the masonry cement sense)
one of a few (organic) solvents, probably one of:
dichloromethane, a solvent used to melt together plastics
tetrahydrofuran, a solvent that is the main part of PVC solvent a.k.a. PVC glue.
butanone, a widely used solvent including in some glues


Poly Cement can refer to

cements that uses polymers instead of lime
e.g. polyurethane cement?(verify)
a solvent - basically, see plastic cement
polystyrene cement, a.k.a. plastic model glue, seems to be this (verify)


Descriptions / typologies

Contact glue describes glues that are applied to both surfaces, dry separately for some time (often between seconds to minutes, up to maybe a day, depending on product and purpose), then be pressed together hard.

While it's a category, they are often specifically neoprene solutions(verify), and you may mostly know them by a specific brand.


Contact glue is practical when gluing larger areas, where the large contact area means the combined strength is plenty even in cases it is not a strong bond.

http://en.wikipedia.org/wiki/Adhesive#Contact_adhesives


Pressure-sensitive glue


Hot glue are [1] thermoplastics] (rather than thermosetters), meaning they can be molten and molded later.

The DIY Hot-melt glue is typically EVA, though there are others. These sticks melt at ~110C, high-temp sticks at ~190C. (cheap glue guns not temperature-controlled very well, meaning that won't know whether a DIY variant heats to, say, ~120C or ~170C)



Specific materials

Gluing wood

Gluing paper

Gluing metal

Gluing glass

Gluing plastics

Brick, mortar, 'n' stuff

Cement: (nl: Cement)

  • Ingredients: mostly oxides of calcium or silicon, plus silicates[2][3](verify)
  • cement is a binder that hardens. It is so fine that it only an ingredient of something bulkier
...although cement+water is sometimes used on walls and floors to get better adherence with the mortar added immediately after
(and some mixes that use cement can also add specific binding agent)
  • two broad classes:
hydraulic cement that hardens in reaction to water
non-hydraulic cement that hardens in reaction to CO2
  • Portland cement is the most common mix used in building (and is hydraulic)
there are many others used in specific uses, like Masonry cement, others[4]


Mortar: (nl: Mortel, specie)

  • Ingredients: cement, sand, sometimes lime
  • relatively fine
  • used for masonry, tiling, plastering, and more
    • probably more sand in mortar for masonry than in tiling

Grout: (nl: Grout)

  • Ingredients: water, cement, and sand
  • grout is thinner than mortar, and flows into gaps
Tiling grout used to finish tiling
Structural grout used to bond steel to masonry

Concrete: (nl: Beton)

  • Ingredients: (portland) cement, sand, large aggregate (gravel/rocks)


Stucco:

  • Ingredients: binder, smaller aggregate
  • may be relatively find or moderately rough, depending partly on whether it's used for protection or decoration



See also:


Plaster, gypsum and variants

Plaster is a generic term, describing function (indoor smoothing/decoration) more than a material. Something similar goes for stucco, though this more usually describes outdoor-resistant variants.

Plaster is often gypsum, lime, or cement. Stucco was originally similar (lime and sand) though later involved portland cement or such for durability, and possibly fibers for strength.


On the building and DIY sides we have some more well-defined mixes.

Gypsum itself is calcium sulfate dihydrate (CaSO4·2H2O), a transparent mineral crystal. It is used in fertilizer, and also as a main ingredient in plaster, drywall, blackboard chalk, and a few other things.


Gypsum plaster, a.k.a. plaster of paris, is calcium sulfate hemi-hydrate (CaSO4·0.5H2O), a dry white powder produced by heating the dihydrate to 150 C. (there are four different hydrated stages, the two just mentioned are generally the most interesting.) With water, gypsum plaster reforms into gypsum,


Quicklime is calcium oxide (CaO)

Lime plaster is calcium hydroxide (Ca(OH)2), a colorless crystal or white powder, which you get mixing quicklime and water.

Also known as slaked lime, hydrated lime, caustic lime, builders' lime, cal, pickling lime


Limestone is calcium carbonate (CaCO3) is the set form of lime plaster, and is a modest portion (~10%) of sedementary rock out there, and e.g. what makes many caves.

Lime refers to calcium oxide or calcium hydroxide, though more broadly can include any of the above


See also:


Clay

https://en.wikipedia.org/wiki/Clay

https://en.wikipedia.org/wiki/Clay_mineral



Household and DIY substances

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)

Salt

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)


The salt we eat is mainly sodium chloride, NaCl.

Table salt is mostly pure sodium chloride

very usually with some anti-caking agents
In various places table salt is iodized.


Iodized salt (sometimes fortified table salt?), contains a few dozen parts per million iodine salt,

as a micronutrient we need and may or may not have another ready source of (like seafood, kelp, other sea vegetables).


Kosher salt is table salt without iodine - so may be pure, though

seems to often still have anti-caking, but may not, in which case it'll clump


Pickling salt - doesn't contain iodine or anti-caking, so is the purest form of NaCl you can easily get,

be aware it'll clump


Dishwasher salt is usually fairly sodium chloride salt, without anticaking - but might contain some processing leftovers so isn't food grade



Soda compounds

In everyday use, "soda" can refer to a few different sodium-based compounds.


In everyday use, it's often:


Sodium carbonate can refer to (Na2CO3) or one of its hydrated forms

  • a.k.a. soda, soda ash, sal soda, washing soda (the last often seems to be the decahydrate, the larger crystals(verify))
  • the unhydrated and monohydrate are powdery. It is hygroscopic, meaning it will absorb moisture from the air and over time become one of the hydrated forms, which clumps into crystals
  • Apparently the name 'soda ash' comes from the fact that sodium carbonate was once once largely extracted from seaweed ashes.
  • uses include
    • water softener: in washing machines, a little soda can be used in combination with detergent: hard water contains magnesium and calcium, which some of the detergent would bind to it instead of being effective; soda takes its place, which is a cheaper solution than using more detergent.
    • as a bleach for cotton, linen
    • in taxidermy, it can be used to clean bones of flesh (used as a fairly strong alkali solution)
    • in swimming pools, it can be used to balance the effect of chlorine, and raise the pH
    • helps certain types of dyeing
    • occasionally used in cooking or other cases of lyeing (where you might more typicall use NaOH)


Sodium bicarbonate (NaHCO3; reacted from soda, CO2 and water)

  • a.k.a. baking soda, bicarbonate, sodium hydrogen carbonate
(and a component in things like alka seltzer).


Sodium hydroxide (NaOH),

  • a.k.a. caustic soda, lye, soda lye, white caustic
  • In dutch: natronloog (not to be confused with bleekloog, which is NaClO)
A strong base, exothermic (generates heat) when dissolved into water.
Dissolves hairs and many fats, so is useful in unclogging drains.
Corrodes aluminium, so not a general-purpose cleaner.

Alcohol

Alcohol is chemical property, and we often see it as a series of related molecules.


The alcohol we drink is specifically ethanol (a.k.a. ethyl alcohol). Chemically, almost all other alcohols are rather toxic even in small amounts; ethanol is toxic only in large amounts.

(There is also tert-amyl alcohol (a.k.a. TAA, 2-methyl-2-butanol), a byproduct of fermented ethanol, found e.g. in beer. It's a minor product and has effects similar to ethanol so we typically ignore it.)

Ethanol is effectively a psychoactive drug, and somewhat addictive. But we had it before laws, we like it, are pretty well informed, and have decent social control, so we consider it fiiiine.


Non-drinkable alcohols you also see frequently include

see below
  • methanol, a.k.a. methyl alcohol (sometimes wood alcohol, because that was once a decent way to produce it)
toxic to us in more-than tiny amounts
itself not as effective cleaner compared to other alcohols, which is why you don't see it much by itself
but still useful in production of other things
and as a fuel
but used as an addition, e.g.
in things like denatured alcohol, where the point of adding it is largely "is toxic, tastes awful"
in/as antifreeze, because it lowers the freezing point of water-based mixtures

Solvents, cleaners, and related nasties

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)


Isopropyl alcohol, a.k.a. isopropanol, IPA, 2-propanol, propan-2-ol,


Turpentine

  • A distilled resin (mostly from pine trees), used to thin some paints and varnishes (yet there are cheaper and less nasty solvents)
  • http://en.wikipedia.org/wiki/Turpentine
  • Dutch: Terpentine; German: Terpentin


Mineral turpentine, a.k.a. turps, white spirit


Denatured alcohol, methylated spirit

  • ethanol-based alcohol (~90% in the US?(verify)) with an addition that makes it taste awful, and probably toxic
Typically using methanol, and/or other things (so that you don't get the bright idea of drinking it for the ethanol when you're out of vodka)
  • may be dyed an unusual color to help identify it
  • the exact composition varies per country
the denaturants used are similar in most places
the differences seem to come largely from alcohol taxation laws
and there are some localized names that can be more specific to content


rubbing alcohol is a generic name (mostly around the US)

  • ≥70% of either isopropyl (often?), or ethyl-based alcohol
plus something to denature it and possibly bitter it, so really don't drink it
if sold as an antiseptic, then often at most 70%, because apparently effectiveness as an antiseptic decreases above that(verify)); rubbing alcohol seems a household name partly for this reason
the name originates from use in massage, though what was originally used for that is actually different(verify)
not recommended in wounds, because it would hurt a lot more than necessary (and dry out the wound a little, which is not what you want for healing)
https://en.wikipedia.org/wiki/Rubbing_alcohol

Surgical spirit seems to be a UK name that is quite comparable to rubbing alcohol

95% denatured alcohol (e.g. 90% ethanol, 5% methanol?)
and, according to the British Pharmacopoeia, 2.5% castor oil, 2% diethyl phthalate, and 0.5% methyl salicylate.


Cleaning alcohol may often be isopropyl or ethanol-based

and may (or may not) contain fewer additives(verify)
also may be anhydrous, containing little to no water (for contrst: the leftover percentage in rubbing alcohol and surgical spirit is water)



White gas (verify)

  • There are a number of products that are a mix of hydrocarbons, useful as a solvent and as fuel, often (CnH2n+2)
with some variation of for what range of n, e.g. dutch wasbenzine is apparently between 5 and 15 (verify)
'white gas' has varied through time (apparently started life referring to additive-free gasoline?)
so in the broadest sense may mean nothing more than petroleum-based fiel
yet now usually refers to a mix of shorter flammable hydrocarbons (apparently mainly cyclohexane, nonane, octane, heptane, and pentane)
camp fuel, particularly a specific brand like Coleman, is likely this -- and more specific
also
naphta can now often mean white gas, but see notes on naphta
Note that white gas is not the same as white spirit.
arguably more of a fuel than a solvent. Its use as a solvent may be milder than things like turpentine or thinner, vaguely comparable to isopropyl, but more likely to leave a residue
Dutch: wasbenzine


Ammonia

Acetone (a.k.a. 2-propanone)

Ethyl acetate

  • cheap solvent/thinner, relatively harmless (to the point it's a natural byproduct in wine), sweet smelling
  • e.g. used in nail polish remover, PCB cleaning


Nail polish remover is one of many (organic) solvents

  • ...but often one of:
    • acetone (probably most common, but also the least gentle)
    • ethyl acetate[6] (often with some isopropyl alcohol)
    • isopropyl alcohol
    • propylene carbonate(verify)
    • acetonitrile[7] - but is more toxic, and banned for cosmetic use in the EU (but currently not america)
...and may include oils, scents, and coloring



spirit vinegar, distilled vinegar, cleaning vinegar (nl: Schoonmaakazijn)

  • more concentrated acetic acid (CH3COOH) than in typical vinegar
typically fermented from alcohol (not distilled, despite the name)
so is often also purer than food-grade vinegar, in that it avoids planty byproducts, sugar, and more
note some possible confusion with food-grade fermented vinegars, like sherry vinegar
useful for cleaning limescale, some fat
cleaning vinegar
is a little more concentrated than typical white vinegar
may have additives like scents
but usually nothing that is visible, because people use it to clean glass
industrial vinegar
20% acid (rather than the five-ish of most others), so be careful with this


For context:

Naphta (Dutch: Nafta) is a mix of hydrocarbons that comes from distilling raw oil.


Some things that are more functional description than anything specific:


Paint thinner (in the context of painting)

Paint stripper

Kwastenreiniger (Dutch, literally 'brush cleaner')

  • May well be turpentine(verify) (when for alkyd/oil paints)


Sticker remover could by many things

though often reasonable amount of xylene, with the rest less defined, often various hydrocarbons



Removing stickers

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)

You can throw a solvent at it, but if you worry solvents may affect the surface it's on, you can try to start gentler and slowly work your way up.


Mild things that may work

  • just your fingernails - whatever you can get off without chemicals is not risky.
Possibly get a guy, their nails are often little harder(verify)
  • washing-up liquid and a soft cloth - tends not to work. But if it does, is nicely mild.
  • tape - apply, press down, tear off. Idea is that you take a little each time. May take a while, if it works at all.
  • oils things - you could start with peanut butter, as an applicant of a small amount at a time. If you're less afraid of affecting the surface, then maybe use pure oil and leave it soak for a minute or two. Tends to work pretty well on the sort of residue that you can sort of push around but have trouble pulling off, although there may be a lower layer of more dried-up glue that it won't get off.
(why does this work? is it that oil may get into the glue-surface interface and peanut butter just happens to be a nice way to dose low amounts of oil?(verify) maybe there's some mild abrasion too?)
  • sticker remover - (usually xylene and hydrocarbons)


be careful with:

  • warming - warm glue is easier to remove, yes, but heating more than a little without locally heating a lot can be difficult
(also works for price tags - I've seen someone in a CD store skillfully use a lighter)
A cloth with hot water may work, but doesn't hold heat very long
Filed under careful because some ways of heating are bad ideas
  • nail polish remover
because you may not know whether it's the harsher acetone, the gentler isopropyl alcohol, or something else


  • wasbenzine (TRANSLATE) - depends on the plastic. Tends to make glossy plastic less glossy. If you use it, have another damp cloth to clean it off immediately.
  • aceton - more so


  • lamp oil - is an oil that might leave residue. Also can be one of a few different things


Unsorted / untested:

  • WD40 (both oil and solvents, so presumably works)


Maybe a bad idea:

  • turpentine - harsh on many surfaces
  • thinner - harsh on many surfaces

Dehumidifiers / Dessicants

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)
  • Hygroscopic substances, often adsorption. Some can be reused (water separates out easily), others are more bothersome
    • Silica gel - often seen in small packages shipped with products. Reusable through (careful) heating.
    • Calcium chloride - one of the cheapest and easiest chemical variants. Anhydrous CaCl (crystals) adsorbs water, which dissolves it (with some minor heat heat). That solution is often collected.
In small quantities it's perfectly safe, e.g. used as a food preservatives and in some doughs. You wouldn't want to drink the amounts used to dehumidify, of course.
  • Electric dehumidifers - e.g. condensation. Don't need refilling, but may still need maintenance


Examples:

  • A few grains of rice is useful for salt shakers, because that works two ways: the rice helps keep the salt from lumping (perhaps more because of mechanics than because of absorption of water), and the salt means bacteria won't like the rice



See also:

Hydrogen peroxide

Vinegar

Bleach

Bleach refers to anything that can whiten clothes, lightens hair, remove stains, and/or disinfects.

Bleaches will mess with proteins, which is also why they're good against bacteria and viruses (and many other small alive things), and also why it's a quick way to make a bunch of water safe to drink (with the footnote that using more than a small, well controlled amount is also not great for you).


Most general purpose bleaches are oxidizers. There are also reducing bleaches, but they are less generic in their use(verify) so rarer.

Stronger household bleaches are typically chlorine-based.

Gentler bleaches, e.g. the stain remover sort, are often a peroxide, typically hydrogen peroxide, in this use known under names like 'oxygen bleach', 'color safe bleach', and others.


Chlorine bleach

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)

Chemically

The more typical and more aggressive household bleach, e.g. used to clean nasty floors and take color from certain fabrics, is typically a chlorine-based bleach, often a hypochlorite (which is alkaline), typically sodium hypochlorite.

Sodium hypochlorite is unstable in solution, and wants to decompose (into sodium chloride and sodium chlorate), so household bleach usually also contains some amount (usually relatively little) of sodium hydroxide (a.k.a. caustic lye) to slow this decomposition - and which also dissolves hair, fat (which is why it's great at dealing with grease), irritates skin, corrodes aluminium. As such, bleach is not really a great general-purpose cleaner.

The active ingredient is chlorine (which is a gas, and dangerous in larger quantities), which is released mainly on use, in an oxydizing reaction.


Uses


In household cleaning use, 'concentrated' means the order of ~5% (sometimes up to 9% or so), which is already too strong for most cleaning use (Stronger variants are used for industrial processes).

Mixing 5% bleach with water in a 1:15 mix becomes ~0.3%, still strong enough for a most cleaning. Relatively few cases call for stronger.

Mixing 5% bleach with water in a 1:40 mix becomes ~0.1%, still effective to against most bacteria and a lot of viruses, and gentler towards people, so safer and cheaper if you want to regularly disinfect surfaces.

Drinking water that uses chlorine to neutralize bacteria and such will usually have less than 0.0004% (4 ppmv / 4mg/L), frequently also via regulation, though this varies per area, and can be rather lower than that.

The necessity varies with e.g. source of the water, infrastructure (typical methodology used (chlorine, UV light, or ozone), state of maintenance of all pipes and the material used)), to the point that people in different countries and different areas associate more chlorine - or less chlorine - with better-quality water.
You can do this yourself (from ~5% solution it's a few drops per liter) but there's a few mistakes you don't want to make (and you probably don't want bleach with fragrance either), so boiling the water is a safer alternative.

Chlorine levels in pools, useful to stop bacteria growth in pools, is typically similar to the last (somewhere between 0.5ppm and 2ppm (0.00005% .. 0.0002%), to be effective but avoid much eye irritation) - and may well be due to regulation or at least convention.

Public pools, outside pools, and particularly jacuzzis and such may be a little higher, for varied reasons (including ease of management).

It can remove stains and/or color from fabrics like cotton -- but will deteriorate others (e.g. wool, silk, various synthetics, leather).




Some reactions / Risks


That typical swimming pool smell significantly involves chloramine, roughly meaning chlorine-based bleach that has already reacted with germs, saliva, sweat, urine, or other amines common in that context. As well as various other organically based things, including cosmetics.

Note that you smell unreacted chlorine much less, so a stronger-than-usual smell at a pool signals there has been more muck it reacted with, so more byproducts. (though that's less certain if you separately also clean with strong bleach concentrations)

At these concentrations it is more the byproducts than the chlorine that are unhealthy.(verify) (If you're trying to manage a pool, there are more footnotes to this, though)


Note that various materials are damaged by bleach.

This includes a number of plastics you will have at home. Some plastics are perfectly safe from this, but others are not, but do you really know your plastics?

Bleach will tarnish some metals(verify).

Longer term exposure to chlorine gas may lead to respiratory issues(verify)


In general, don't mix hypochlorite style bleach with other cleaning products.

Plenty of combinations are safe, but a few are bad, and will you really remember the full list? It's not really something you want to figure out by trial and error...

The problem is that some combinations (e.g. vinegar, ammonia, cleaning alcohols, acids) cause reactions that quickly release much of the chlorine as gas, and/or interesting things like chloroform, chloramine, hydrochloric acid, chloroacetone, and more.


Other things you don't want

Since these weaken/damage proteins

don't use these on protein fabrics (wool, silk, mohair, leather).
synthetics vary - e.g. polyester, nylon, and acrylic seem fine, while e.g. polyether (so e.g. spandex) is not.



https://en.wikipedia.org/wiki/Bleach -->

Ingredients you might wonder about

Surfactants

Oils and waxes

Some oil terms

Cold pressed means the oil was never heated over a certain temperature (30 degrees or so, varying) during processing - which means more nutrients and less degradation. (though does it necessarily exclude solvent extraction?(verify)) This matters more to nutrition in food, but you may find some texture difference for massage as well.(verify)


Virgin, commonly associated with olive oil but also relevant to others, is often the same thing as unrefined.

This can be meant both in the sense that only physical pressing was used to get the oil, and no chemical process(verify), but also that it has more impurities, which seems to be why there are extra terms like extra virgin to be associated with not-chemical and high quality oil.


Refined, seen on many oils,

can mean a chemical process was used,
or sometimes that lower quality oils were mixed in (usually under quality controls), to give oils that are cheaper but still with most of the consistency and taste of the nicer oil in there.


The label 'organic' does not necessarily imply the absence of refining processes, but regularly does.


Fractionated oils refer to separation of different-length molecules, which is relevant when a plant produces a mix and you want a specific consistency of oil.

A good example is coconits, which produce several oils(verify), some of which are liquid and some solid at room temperature. So coconut oil as the original mix is chunky, 'fractionated coconut oil' usually refers to the smooth liquid-at-room-temperature part of it.[8] (note that not all fractionated oil is created equal, e.g. fractionated coconut oil for massage cares a little less about residues from the fractionation)

Vegetable and mineral oils

Castor oil

Cooking fats

Lamp oils

Candle waxes

Other things you might burn

Points

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)


Gel point - the point below which it is frozen enough that it can no longer flow

very relevant for fuels
There are similar concepts like cloud point and pour point, that most of us won't really care about.


Smoke point, sometimes burning point, is the temperature at which external will start to decompose it, and a little more temperature proably smoke as well

we mostly care about this around oils we eat, because this is bad for taste, and also not too healthy
note: doesn't mean it's on fire (but that's often not much higher)
Perhaps most interesting for fats, because unlike a lot of oils, they have a smoke point that is well away from the flash point.
Oils with higher smoke points can be more practical for stir frying, deep frying and such.


Flash point is the temperature above which something will light on fire if there is an ignition source.

does not necessarily mean that burning itself produces enough vapour for it to continue burning, though.


Fire point is the lowest temperature above which igniting it also produces enough vapour for the burning to also be self-sustaining.

This is often relatively close to the flash point, so safety-wise you care mainly about the flash point.


Auto-ignition temperature, a.k.a. self-ignition temperature, is the point at which something acts as its own ignition source (in a normal atmosphere).

This is generally higher than we need to worry about.
Even most fuels, which are very happy to burn, tend to have an auto-ignition temperature above 200°C



Examples

Olive oil has a gel point around 10°C, making it harder to pour

and starts to solidify (and thereby cloud up) around 4°C
and a flame point around 200°C


Gasoline has gel point around -70°C, a flash point around -40°C, and an auto-ignition temperature around 280°C.

Diesel has a gel point around 10°C, a flash point above 50°C and a self-ignition temperature around 210°C.

Kerosene has a gel point around -40°C, a flash point around between 40C and 70°F(verify) depending on variant, and a self-ignition temperature around 220°C

This means diesel is safer than gasoline (which will always happily burn) but also needs pre-glow, and kerosene is somewhere inbetween.


Pure alcohols tend to have a flash/fire point around 10..15C

e.g. methylated spirit burns very well

Drinkable alcohol mostly doesn't, because most of the liquid is water

below approx 25% the water vapour puts it out(verify)
at 30% you get tiny bit of flame, but not very exciting
even 40% is a lowish controlled flame
only really strong alcohol (50% to 75%) is any fun in terms of fire
used to be a simple test that a strong whiskey wasn't watered down(verify) (though today whiskeys are often ~40%)


Lamp oil is often a mix with an intentionally fairly high flame point, like 60..100C, to make it safe to store


Waxes have a high flame point - and often a melting point above room temperature ((malleable) solid at room temperature is what makes them consider them wax instead of oil)

e.g. paraffin waxes, though a melting point around 40C, have a flame point around 200..250C
which is part of why it's easy to burn them slowly around a wick


Linseed oil has a flash point around 50°C, and a self-ignition temperature around 340°C

Massage oils

Some massage oil terms

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)


I recommend reading up on massage oils elsewhere. There are far better resources than a few paragraphs here.

That said:


If looking to purchase a pure oil for massage, look for terms like carrier oil and base oil, because the purpose of these is to be neutral enough that you can add your own essential oil. This often few other additives as well, and will only have their natural smell, which for most oils is subtle.


Essential oils are distilled oils, typically vegetable. As-is, these are highly concentrated, highly aromatic, and easily irritants (or even toxic at that concentration) and are intended to be added to a much larger volume of base oil.

You may wish to avoid them - or perhaps get an essential oil you really like separately, so you can add your favourite essential oil to your favourite base oil yourself.



Practical hints

Massage oil and sexytimes

Linseed oil

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)


Linseed oil, a.k.a. flaxseed oil, flax oil (dutch: nl, nl) is the oil from ripe flax plant seeds.

It is one of the better known drying oils (alongside tung oil), which are the oils that harden when exposed to air.


Pure/raw linseed oil is edible, though more easily becomes rancid than various other oils, and has a low smoke point, both making it somewhat impractical for cooking.

It is used as an ingredient in some soaps, some putty, some resins. Also some varnishes and some paints, but now largely replaced there.

Even as a product by itself it may be mixed with solvents, resins, and other oils.

It is central to linoleum.


Boiled linseed oil is a variant that oxidizes / polymerizes / hardens more, and faster(verify) than raw linseed oil.

It's a chemical change, not just a temperature one. (The name comes from an old process of boiling it together with lead oxide. There are better processes now.)


Boiled linseed oil is useful for wood you put outside, because it's thin enough to impregnate it.

It needs more frequent upkeep over time because it is still softish, and not as protective as harder things like stains and varnishes, but is much better than nothing and is a natural rather than petrochemical oil.

There are some products for wood that are linseed mixed with other things.



Safety

The reaction of boiled linseed oil with oxygen is exothermic.


The point is that in theory it could heat itself to the flame point where an external ignition will make it burn well, or even catch on fire.


This won't happen easily, but it can.

There are too many youtube videos that try to convince you about a real risk with plain lies, which feeds an argument in a form that is stupid on both sides.

Linseed's flash point (where you can light it easily) is around 95°C , its self-ignition point (where spontaneous combustion happens) is around 340°C.


If you wanted to do this intentionally, you might

  • have a rag or paper containing a relatively small amount of oil
Too little might not have enough fuel to keep reacting long enough. But it also seems that drenching it might actually help distribute heat(verify) - there are a few interplaying reasons why an open pot of it is not going to explode.
  • put in a confined place where heat can build up much faster than it can leave
so that it actually builds up, and doesn't reach some equilibrium
  • with no draft, so probably a closed container, but with a way for some oxygen to convect in or it'll starve itself
  • it can't hurt to have some external heat, like a very hot day and direct sunlight to help heat that confined space a dozen or two degrees to start with,


...then add enough time for it to build to 95°C for a cigarette based accident.

Because having it build up to 340°C to burn your house down without help requires a much more specific of a situation, that I'm not sure I could even engineer intentionally.


That's such a specific list that most of the time, you still only end up with a mess that was temporarily fairly warm.

That said, trash cans actually fit that list fairly well, more so if multiple people used a lot of rags in a day... anecdotally, most reports of "yes this happened" seem to happen around woodworking shops.

Dramatic youtubes are often either engineering it or probably just set it on fire themselves because it wasn't happening fast enough and I'm sure it's true right?

Grease and lubricant

Not too tight, not too loose

Lubricating rubber

Moderately specific products

WD-40

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)

The intent of WD-40 was to prevent corrosion (the WD stands for "water displacement", and apparently the fourtieth formulation in a series(verify))

WD-40 seems to be a mix of mineral oil and solvents.


It is sometimes through of as a grease, yet it is at best a mild lubricant, and sort of barely that.

If it's on top of something dry, great, if not necessarily for very long.

However, if something was greased, then the WD-40's solvents may have just washed much of that away, and replaced it with mineral oil which is less likely to stick around.


Brake cleaner

Loctite

Tape

Tape around electronics

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)


Electrical tape

Often PVC, sometimes other plastics (once upon a time, friction tape was used)
electrically insulating, heat resistant, a little stretchier and a little harder to tear than some other tapes you might think to use
there are variants with fiberglass cloth
the glue on some PVC tapes isn't ideal for the use, in that heat may lead to slip, is more easily left it behind, making it a sticky mess


Polyimide tape, e.g. kapton (kapton is a brand - that became genericised) - but note that not all things called kapton are the same

doesn't stretch
may not tear so easily (though may puncture)
seems happy within roughly -100°C to 300°C
chemically inert, resistant to a good deal of oils, solvents, acids
generally uses an adhesive that lasts (silicone or acrylic?(verify)), so less likely to come loose later
doesn't outgas (itself; the adhesive might)
typically peels off without leaving adhesive
doesn't wear nearly as much as PVC tape, so is also used where you would normally think of electrical tape even if the temperature rating is irrelevant
most variants won't create static electricity when peeling (like office tape does), can be useful around sensitive electronics
polyamide film is sometimes used around soldering - particularly rework with hot air
it's also great for controlling where solder won't go (a temporary solder mask), which can e.g. be useful for cleaner drag soldering
It's not that it prevents heat from passing (it does so only about as good as other plastics(verify)) - it's distinct from heat tape
it's the act of leaving an air gap that does that, and the fact that it doesn't melt then really helps

Mechanical, construction

Specialized

Heat tape

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)

Materials

Some plastics / polymers

These are primarily notes
It won't be complete in any sense.
It exists to contain fragments of useful information.

The word plastic refers to the ability to mold it.

In the set of "things that occur naturally, or we've managed to make", that turns out to most often describe polymers of high molecular mass, and often from hydrocarbons.


We've extended the idea - and also control the polymerisation process better than nature can - so we can get much more specific, and long-chained polymers, that don't appear naturally, which is why nature doesn't know how to deal with them: Polymers are chemically robust, and something that doesn't break down sits around.


Even a chemically specific plastic can vary in robustness, depending on how much you polymerize it. Also in feel - there are some plastics you know as hard glass-like panels or boxes that can also be extruded into thin threads and woven into a soft fabric. This also makes it harder to tell what any plastic is (sometimes even that it is a plastic, assuming you don't see a printed code, and/or have just held it in fire).


Some of the plastics most commonly used in everyday objects are labeled with chasing-arrow triangle () with a number in it.

This is the ASTM resin coding system / RIC (Which does not necessarily indicate that it is recyclable, but easy identification certainly helps separate the ones that are from those that aren't, and separate them from each other so you can repeat that recycling)

1 PET (a.k.a. PETE)
2 HDPE
3 V
4 LDPE
5 PP
6 PS
7 other (may mention another acronym)

RIC seems to refer to just these, and this seems based in the US.

The EU's is essentially an extension of RIC, so more fine grained

China's is a different extension.

Japan's looks a little different


There's also the angled bracket things, which seems more like a convention(verify), which looks like >PP<, >SAN<, >PC+ABS-FR(40)<, or >PA6-30< (Polyamide/Nylon), which seem to use the same sort of acronyms, with some additions, like that FR(40) seems to indicate the amount of fiber reinforcement.


(suggestions of where to find more about this coding is quite welcome)


A wider set of common plastics include:

Polyethylene (PE) (a.k.a. polythene, polyethene)

probably the most common plastic.
thermoplastic, so can be recycled decently

Seen in various forms[9], some of the common ones including:

  • low density polyethylene (LDPE) -
e.g. transparent plastic bags, dispensing bottles, tubing, white-opaque foamy wrapping, more
4 in the coding system
  • linear low density polyethylene (LLDPE)
In comparison to LDPE: can be thinner, somewhat harder to process (e.g. extrude)
e.g. plastic bags, plastic wraps, lids, tubing, more
  • high-density polyethylene (HDPE)
various (harder, stronger) bottles (alternative to PET), plastic bags, tubing,
2 in the coding system


Polyester is a fairly general term, though it is frequently used to refer specifically to PET [10]


Polyethylene terephthalate (PET, or occasionally PETE), perhaps best known for its use in soda bottles [11]

recycled, though avoid constant reuse yourself - the surface is mildly porous so retains bacteria and flavour - there are better choices for containers you reuse a lot
1 in the ASTM coding system


Polyurethane (PUR, PU) is seen in various forms, including flexible and rigid foam, gel, and an mildly flexible plastic. [12]


Polypropylene (sometimes PP), [13]

5 in the ASTM coding system
seen e.g. in straws, bottle caps (regardless of the container plastic)
also used around kitchens (e.g. alternative to PVC pipes) and food (e.g. our juicer's collection bucket is PP), in part because it is one of the more inert plastics(verify), which is also roughly why this is harder to glue


Polyvinyl chloride (PVC) under some specific uses (e.g. pleather), and also vinyl (even though PVC is technically one of various vinyls) [14]

3 in the ASTM coding system


Nylon (actually a grouping name) [15]



Acrylonitrile Butadiene Styrene (ABS)

frequently combined with polycarbonate (PC+ABS), which is stronger just ABS alone and cheaper than just PC


Polylactic Acid (PLA) (a.k.a. polylactide) is a thermoplast

derived from renewable crops
biodegradable
one of the plastics used in 3D printing
mechanically similar to PETE, but not very temperature resistant


Polystyrene (PS?)

thermoplast (~100C)
not very biodegrable
6 in the ASTM coding system
styrofoam (a brand name) is a specific form of polystyrene - (closed-cell) extruded polystyrene foam


High-Impact Polystyrene (HIPS)

Polycarbonate (PC) technically refers to a group of polymers, and practically often to sheets that look similar to acrylic sheeting. Such polycarbonate is stronger and less brittle under load (and costs perhaps 20-30% more).

Trade names include lexan, makrolon,

Harder to bend than acrylic/plexiglass, in part because it's more heat-resistant, and in part because it turns out that the softening and melting temperatures are closer together.


Polymethyl methacrylate (PMMA), more commonly known under names like acrylic glass, and brand names like perspex, plexiglass/plexiglas, lucite and others[16]

There is some variation in quality and construction.

Somewhat hard to work on, as power tools (drilling sawing) will easily create local stress that lead to local cracks in ways you don't want it to (and which easily spread), and you may also heat the plastic to melt to the tool, or at least stink a bunch.



Some tools are handier than others - bandsaws apparently work well to avoid stress, but may still be a problem in terms of heat.

It seems to be easiest to (like glass) create a weak line edge by scoring, then break it off at the edge. It'll bend before it breaks, and it doesn't follow weakness quite as easily as glass does, so for longer breaks you need to do more scoring than you would with glass.

While the glass transition phase temperature varies with the exact copolymer that a speciic product, most lie around 105C (220F), so you can shape these using heat. Often done with a strip heater (better controlled, avoids overheating), a more custom made wire resistance heater, or even a paint stripper gun. You can get creative with shapes, but most bends are probably straight-line bends, or sometimes slower wavy bending - but you usually want to support the new shape somehow if you do that.

Try to heat evenly, gradually, and don't overheat. You also want to work on dry sheets.




Flexible

Rubber, synthetic rubber, latex: Latex is the name of the sap, rubber a derived product.

...although various naming blurs that distinction - think moulding latex, liquid latex, latex sheeting. [17] [18] [19]


Nitrile rubber is a copolymer. It is also known as just nitrile, e.g. in 'nitrile gloves' [20]





Rubber

"Synthetic rubber"

Decomposing rubber

Foams and other fillers

Things you might for example consider to stuff pillows with

Note that firmness and compression over time varies not only with material but also with process.



In the widest sense, foam means 'gas trapped in anything', from soap bubbles to packing materials to the insulating walls of the International Space Station.

Most of the time it refers to some lightish springy stuff that we e.g. can sit on, use for padding, use for isolation, and such.



Ratings

Open cell structure foams

This article/section is a stub — probably a pile of half-sorted notes and is probably a first version, is not well-checked, so may have incorrect bits. (Feel free to ignore, or tell me)

These breathe.

polyurethane foam

Polyester foam
Rebond foam
HR foam
Memory foam

Dryfast foam

melamine

Closed-cell foams

Neoprene Foam

Syntactic foam

EVA

Polyethylene Foam

Purposes

Lessening sound reflection

Sound isolation

Dealing with moisture

Unsorted

Wood

Engineered wood

Refers to wood made for a specific use/strength, look, or such.

Regularly composite wood, regularly pressed wood, though not necessarily either of those.

Plywood

Underlayment

Oriented Strand Board (OSB)

structural composite lumber

Laminated veneer lumber (LVL)
parallel strand lumber (PSL)
laminated strand lumber (LSL)
oriented strand lumber (OSL)

Fiberboard

Particle board
MDF (Medium Density Fiberboard)
Hardboard

Parallel-strand lumber

Glued laminated timber

High-Pressure Laminate

Stamina wood

Translations

Semi-sorted

Wood in saunas


Walls and bricks