Seanz0rz
05-05-2009, 06:49 PM
I've had some questions posed to me concerning my plastic projects. i have probably a few thousand hours of research into the subjects, and heres a quick run down of what ive learned:
know your plastic! its easy to say something is made of plastic, but what kind? most interior pieces in our trucks are a strange concoction, but luckily it will be stamped on the back of every piece what it is. most other items will tell you what they are, with a letter code in brackets like this: >ABS< or >PE< or sometimes the recycle triangle with the abbreviation underneath.
some examples of uses of common plastics:
ABS - alot of consumer electronics housings. ive sourced scrap abs plastic from old routers, mice, keyboards, VCR's, etc. also, you can find abs plastic in pipe and fitting form at your local home center. finding sheets requires finding a plastics specialty store, or somewhere online.
PVC - polyvinylchloride is often found as white water pipe at home depot. other thing are made of it, but not terribly common for our purposes.
acrylic - acrylic, often found in the glass section of home depot, is the most widely available in sheet form. commonly known as plexiglass and lexan. very useful plastic!
PE - both low density (LD) and high density (HD) PE, or polyethylene are by far the most common plastics in our households. everything from ketchup bottles to zip lock bags are a form of PE. they are both incredibly resistant to solvents, and are relatively inert, making them perfect for food storage.
PP - much like PE, polypropylene is relatively inert and resistant to most solvents. both PP and PE will often have a waxy feel to them, depending on their manufacturing process.
special note: My research was all based around the plastic that makes up a 3rd gen's center dash bezel. this is >PPE+PS<. PPE is much like PP and PE, and gives the plastic its waxy feel. however, the PS, or polystyrene, component, allowed me to adhere ABS to it. without this PS component, i would have been dead in the water.
next, find an appropriate solvent for your plastic. generally speaking, acetone and MEK will work for just about anything, except PE and PP. Acetone will evaporate faster than MEK, so take that into account for your project. typically acetone is the better choice, and by no means is it an instant cure time. never mix the two solvents!
we use these facts to our advantage to make glue and shallow fill material. for me, this means making "sludge." sludge is chips or shavings of your plastic of choice, dissolved in your solvent of choice. generally, you should always try to match your sludge material to the plastic your working on. the ideal consistency is up to you. what works best for me is the consistency of honey at a cool room temperature or so. the smaller the pieces going into the sludge, the quicker they will dissolve. now for a vessel. glass is always an option, but it is very difficult to apply this material from a glass jar. using our knowledge of solvents, we see that PP and PE are perfect containers for this material. personally, i use a plastic bottle i found at walmart in the cookware section. this one is clear and comes with a cap, they also have red and yellow ones for ketchup and mustard, but those lack caps. this bottle is perfect, and i have a few extras lying around for trying out different consistencies and solvents. i have also experimented with poking a very small hole in a quart size ziplock and using it like a pastry bag. both work well, but i feel i have much more control with the bottle.
this sludge works as a glue and filler. the acetone in the sludge will actually work to dissolve the plastic its applied to, and once evaporated off, will leave one solid piece of plastic, as opposed to 2 pieces joined with an epoxy or glue. this becomes an extremely strong joint.
i get my plastic sheets from a local supplier, S&W Plastics in San Bernardino, CA. you can order it online from McMaster-Carr, and other places. i pay about 2.25/square foot.
to cut plastics, i am using a bandsaw with a fine tooth scroll blade on it. you can also cut it with a razor knife, although i would recommend against it. a jig saw or any saw with a fine tooth on it will work great. you can also cut it with a dremel, though it is very difficult to keep the plastic from melting. of course the usual warnings apply, in addition to this: cutting generates friction, which in turn generates heat. molten plastic burns, bad. so be careful!
a great resource for research: http://www.ides.com/plastics/default.htm
plastic is SO easy to work with! so much easier than metal! please, if you have any questions about ANYTHING concerning plastics, please post it here and i will do my best to answer it, or point you in the direction of someone or somewhere that can help you. plastics are an amazing material, but can seem very intimidating. with a little basic knowledge of the plastics most common to us, you will find there are so many opportunities to do wonderful and creative things with the material.
//hopefully this will become wiki-ized someday
know your plastic! its easy to say something is made of plastic, but what kind? most interior pieces in our trucks are a strange concoction, but luckily it will be stamped on the back of every piece what it is. most other items will tell you what they are, with a letter code in brackets like this: >ABS< or >PE< or sometimes the recycle triangle with the abbreviation underneath.
some examples of uses of common plastics:
ABS - alot of consumer electronics housings. ive sourced scrap abs plastic from old routers, mice, keyboards, VCR's, etc. also, you can find abs plastic in pipe and fitting form at your local home center. finding sheets requires finding a plastics specialty store, or somewhere online.
PVC - polyvinylchloride is often found as white water pipe at home depot. other thing are made of it, but not terribly common for our purposes.
acrylic - acrylic, often found in the glass section of home depot, is the most widely available in sheet form. commonly known as plexiglass and lexan. very useful plastic!
PE - both low density (LD) and high density (HD) PE, or polyethylene are by far the most common plastics in our households. everything from ketchup bottles to zip lock bags are a form of PE. they are both incredibly resistant to solvents, and are relatively inert, making them perfect for food storage.
PP - much like PE, polypropylene is relatively inert and resistant to most solvents. both PP and PE will often have a waxy feel to them, depending on their manufacturing process.
special note: My research was all based around the plastic that makes up a 3rd gen's center dash bezel. this is >PPE+PS<. PPE is much like PP and PE, and gives the plastic its waxy feel. however, the PS, or polystyrene, component, allowed me to adhere ABS to it. without this PS component, i would have been dead in the water.
next, find an appropriate solvent for your plastic. generally speaking, acetone and MEK will work for just about anything, except PE and PP. Acetone will evaporate faster than MEK, so take that into account for your project. typically acetone is the better choice, and by no means is it an instant cure time. never mix the two solvents!
we use these facts to our advantage to make glue and shallow fill material. for me, this means making "sludge." sludge is chips or shavings of your plastic of choice, dissolved in your solvent of choice. generally, you should always try to match your sludge material to the plastic your working on. the ideal consistency is up to you. what works best for me is the consistency of honey at a cool room temperature or so. the smaller the pieces going into the sludge, the quicker they will dissolve. now for a vessel. glass is always an option, but it is very difficult to apply this material from a glass jar. using our knowledge of solvents, we see that PP and PE are perfect containers for this material. personally, i use a plastic bottle i found at walmart in the cookware section. this one is clear and comes with a cap, they also have red and yellow ones for ketchup and mustard, but those lack caps. this bottle is perfect, and i have a few extras lying around for trying out different consistencies and solvents. i have also experimented with poking a very small hole in a quart size ziplock and using it like a pastry bag. both work well, but i feel i have much more control with the bottle.
this sludge works as a glue and filler. the acetone in the sludge will actually work to dissolve the plastic its applied to, and once evaporated off, will leave one solid piece of plastic, as opposed to 2 pieces joined with an epoxy or glue. this becomes an extremely strong joint.
i get my plastic sheets from a local supplier, S&W Plastics in San Bernardino, CA. you can order it online from McMaster-Carr, and other places. i pay about 2.25/square foot.
to cut plastics, i am using a bandsaw with a fine tooth scroll blade on it. you can also cut it with a razor knife, although i would recommend against it. a jig saw or any saw with a fine tooth on it will work great. you can also cut it with a dremel, though it is very difficult to keep the plastic from melting. of course the usual warnings apply, in addition to this: cutting generates friction, which in turn generates heat. molten plastic burns, bad. so be careful!
a great resource for research: http://www.ides.com/plastics/default.htm
plastic is SO easy to work with! so much easier than metal! please, if you have any questions about ANYTHING concerning plastics, please post it here and i will do my best to answer it, or point you in the direction of someone or somewhere that can help you. plastics are an amazing material, but can seem very intimidating. with a little basic knowledge of the plastics most common to us, you will find there are so many opportunities to do wonderful and creative things with the material.
//hopefully this will become wiki-ized someday