Homemade Polystyrene for piston
- jrrdw
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From here on out if you guys (jsr) are going to quote me, make sure you quote me entirely, (jsr). If you had done so anyone else who reads this entire threat will ba able to understand whats going on.
@JSR, partly quoting me like that is a cheep shot, and I don't deserve that!
@carlman, my member name is "jrrdw" get it right all ready.
@JSR, partly quoting me like that is a cheep shot, and I don't deserve that!
@carlman, my member name is "jrrdw" get it right all ready.
- jackssmirkingrevenge
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Amended and linked to the other thread.
My apologies, didn't mean to cause offence or make you look bad. On the contrary, you're just doing your job and it's understandable. I just thought it was a shame that a legitimate and useful construction technique (and I can see many applications for spudgun fabrication) was being suppressed on the off chance that it might be abused.
My apologies, didn't mean to cause offence or make you look bad. On the contrary, you're just doing your job and it's understandable. I just thought it was a shame that a legitimate and useful construction technique (and I can see many applications for spudgun fabrication) was being suppressed on the off chance that it might be abused.
- Carlman
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Well soooory mr jrrdw!jrrdw wrote: @carlman, my member name is "jrrdw" get it right all ready.
I have mistyped you name a couple of times...
I get called cartman, carman and various other variations of my username.

Aussie spudders unite!!
- jrrdw
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I'm more concerned with safety issue's then abuse, and I'm glad members understand that, or hope they do and will.
Side note: How about Rumpilstilskin, ever been called that?


Side note: How about Rumpilstilskin, ever been called that?





- Technician1002
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Not in the last 425 years.. But I've been called older than the hills. Most hills are older though.jrrdw wrote:
Side note: How about Rumpilstilskin, ever been called that?

***EDIT*** I should say something on topic..

Due to the strength of the method to create the part, would it be plausible to work in a layer of either fiberglass mat or carbon fiber for strength and impact resistance?
Last edited by Technician1002 on Mon Apr 20, 2009 9:59 am, edited 1 time in total.
- mark.f
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I don't see what safety issues there could be.
Most if not all PVC primers contain much worse than acetone. Think M.E.K. and other nasty stuff. Not to mention carcinogens. Hell, most <strike>epoxy</strike> polyester resin hardeners contain a diluted high explosive.
The finished parts would be good for zero-pressure applications, like valve-pistons and other components, but not for holding pressure. Too many imperfections and faults.
So, to get to the point, yes, this would be good for a piston.
Most if not all PVC primers contain much worse than acetone. Think M.E.K. and other nasty stuff. Not to mention carcinogens. Hell, most <strike>epoxy</strike> polyester resin hardeners contain a diluted high explosive.

The finished parts would be good for zero-pressure applications, like valve-pistons and other components, but not for holding pressure. Too many imperfections and faults.
So, to get to the point, yes, this would be good for a piston.
Perfect material, but isn't solid polystyrene quite brittle? Surely expanding PU foam moulded into the right size would work too?
I saw that how to and only just remembered about it's less safe uses when I read through this topic. If we wanted to cause trouble or hurt ourselves, then almost every how-to on this site details one way or another (spudgunning isn't exactly as safe as cloud watching! )
I think if we can be trusted with lethal weapons, we can be trusted with some melted plastic.
Please don't read this as sounding angry or preachy, you can cut out the off topic if you want. I am pleased that you didn't just delete the topic altogether, as censorship is something I feel strongly about.
I saw that how to and only just remembered about it's less safe uses when I read through this topic. If we wanted to cause trouble or hurt ourselves, then almost every how-to on this site details one way or another (spudgunning isn't exactly as safe as cloud watching! )
I think if we can be trusted with lethal weapons, we can be trusted with some melted plastic.
Please don't read this as sounding angry or preachy, you can cut out the off topic if you want. I am pleased that you didn't just delete the topic altogether, as censorship is something I feel strongly about.
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety. -Benjamin Franklin
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Well if the mods said that it is dangerous, must I delete the post? I´m not going to discuss it.
I hit the catridge with a metal hammer 4-5 times and It didn´t break. My piston isnt going to run at very high pressure. I will usually pressurize
at 85psi, the same as my PVC gun.
I only wanted to make a piston stronger than hot glue.
I hit the catridge with a metal hammer 4-5 times and It didn´t break. My piston isnt going to run at very high pressure. I will usually pressurize
at 85psi, the same as my PVC gun.
I only wanted to make a piston stronger than hot glue.
- jackssmirkingrevenge
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It was discussed and approved, non te precupeseuskalspud wrote:Well if the mods said that it is dangerous, must I delete the post? I´m not going to discuss it.

I too disagree with the locked thread. Locking it does not seem right, it is still there that people can do it, but bars reasonable discussion. Thats like barring PVC related threads, PVC is used in solid and hybrid rocket motors, the two parts of epoxy are rated "3" in the health category, and one has a explosive property. PVC primer and cement can easily be made into a explosive. OH NOES!
Yes there are measures taken with these products that make it difficult to happen, but I can site at least one case from each example where someone did it.
I bet some of the people here didn't know about napalm until the thread was locked, and it was brought up.
@euskalspud: If a thread is locked (even if its not), you can't delete it. Sometimes people go back and remove the content though.
EDIT: weird... i wrote this yesterday, but my comp sent it out today....
Yes there are measures taken with these products that make it difficult to happen, but I can site at least one case from each example where someone did it.
I bet some of the people here didn't know about napalm until the thread was locked, and it was brought up.
@euskalspud: If a thread is locked (even if its not), you can't delete it. Sometimes people go back and remove the content though.
EDIT: weird... i wrote this yesterday, but my comp sent it out today....
Last edited by rp181 on Mon Apr 20, 2009 2:04 pm, edited 1 time in total.
- john bunsenburner
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Ironic that i had an instructable about acetone and styrofoam plastic in my sig for months...Oh well shows that the process is used, makes me happy(i didn't invent it, but seem to be one of the first to bring it up here, you are amongst the first 10). I am not sure if this can really be trusted with any pressure higher than 100psi(but bleroticon can!). What I like to use this for is for filling spaces up and to make projectiles, as it can be molded into most any shape with most molding materials and consistency can be adjusted(from watery, over cum like up until bread dough like). One suggestion I do how ever have! Use gasoline instead of acetone, its cheeper and easyer to get(also technically its a lot safer if you think about organic peroxides and how easily...ahem...)
Use lubricants in your molds, i am not sure about this stuff but i can tell you many stories of me standing on my work bench with a clamped down pipe and a pair of pliers trying to pry out epoxy pistons...
Look into the patato plastic too(hey jrrdw, can you fix the link, i cant get it to work
)
In the end really most plastics, be it epoxy or this should not be trusted with very high pressures, but I my self would be very keen to know exactly how high as I am unfamiliar with epoxy at higher pressures and do not wish to mis-inform you, perhaps JSR knows that.
Use lubricants in your molds, i am not sure about this stuff but i can tell you many stories of me standing on my work bench with a clamped down pipe and a pair of pliers trying to pry out epoxy pistons...
Look into the patato plastic too(hey jrrdw, can you fix the link, i cant get it to work

In the end really most plastics, be it epoxy or this should not be trusted with very high pressures, but I my self would be very keen to know exactly how high as I am unfamiliar with epoxy at higher pressures and do not wish to mis-inform you, perhaps JSR knows that.
"Did you ever stop to think that out of the seven deadly sins envy is the only one which doesn't give the sinner even momentary pleasure"-George Will
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So, What shoud I use for 80 psi mini coaxial, hot glue, this plastic, wood...?
- john bunsenburner
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hot glue will do for 80psi, i persume this would too, wood i dont really like to work with, jsr would suggest epoxy at this point, anything that comes to mind from a piece of cork to this is ok at 80psi in a mini.
"Did you ever stop to think that out of the seven deadly sins envy is the only one which doesn't give the sinner even momentary pleasure"-George Will