Does anyone know of a plastic that I can buy at my local hardware store that
I would be able to melt and pour into a mould? I just want to practice and
create a few parts from plastic before I try and use metal?

How about using wax..it would IMHO be a bit more suitable. Plastics do
not flow well even when melted. Usually plastics use a high pressure
injection system to fill a mold, where metal can be sand cast,
pressure cast, centrifugal cast etc etc......so unless you have a
means of injecting or forcing the melted plsatic into the mold it may
be a big headache to try plastic. Just my 2 cents worth..

For all I know you may already have a plastics injection machine. What
type of molds are you using and what metal do you hopefully intend to
use for a finished item? Common plastics used are styrene and
polyethelene types, both of which can be found pretty easy in any
Wally Wolrd store in the toys department or use some old milk jugs,
plastic buckets etc.

On Mon, 9 Jan 2006 14:32:50 -0500, "HotRod"
wrote:
Does anyone know of a plastic that I can buy at my local hardware store that
I would be able to melt and pour into a mould? I just want to practice and
create a few parts from plastic before I try and use metal?


--
\\\|///
( @ @ )
-----------oOOo(_)oOOo---------------


oooO
---------( )----Oooo----------------
\ ( ( )
\_) ) /
(_/
The original frugal ponder! Koi-ahoi mates....

this is usually called lost wax. look for something called victory brown
casting wax. you can also use silicone and/or various types of rubber, which
you'll need if your mold has any undercuts in it, or you don't want to
destroy the mold to get the object out of.

regards,
charlie
http://glassartists.org/chaniarts

"HotRod" wrote in message
...
Does anyone know of a plastic that I can buy at my local hardware store
that I would be able to melt and pour into a mould? I just want to
practice and create a few parts from plastic before I try and use metal?

You could use hot melt glue. Or polyester resin or even acrylic resin
dust from sawing sheets of plexiglas. disolve it in methylene chloride.
Easiest is the polyester resin. I did itwhen I was twelve years old

I want to cast some basic copies of parts and then make some additions and
changes to the plastic mold. I will then re-cast a negative mold to create
the metal part. Right now I'm thinking of aluminum parts but right now this
is more hobby than anything. How would I tell if a product is made of
styrene or polyethelene and what do they melt like? Making an injection
system will be simple if thats whats needed.

"Roy" wrote in message
...
How about using wax..it would IMHO be a bit more suitable. Plastics do
not flow well even when melted. Usually plastics use a high pressure
injection system to fill a mold, where metal can be sand cast,
pressure cast, centrifugal cast etc etc......so unless you have a
means of injecting or forcing the melted plsatic into the mold it may
be a big headache to try plastic. Just my 2 cents worth..


Yep, injection molds use very high pressure. I think wax would work much
better.

On Mon, 9 Jan 2006 14:32:50 -0500, "HotRod"
wrote:

Does anyone know of a plastic that I can buy at my local hardware store that
I would be able to melt and pour into a mould? I just want to practice and
create a few parts from plastic before I try and use metal?

A good hobby store will have pourable casting resins. You mix two
liquids and pour the mixture into the mold, where it hardens into a
plastic.

The urethanes work better but they cost more. Alumilite is one
brand.

HotRod wrote:
I want to cast some basic copies of parts and then make some additions and
changes to the plastic mold. I will then re-cast a negative mold to create
the metal part. Right now I'm thinking of aluminum parts but right now this
is more hobby than anything. How would I tell if a product is made of
styrene or polyethelene and what do they melt like? Making an injection
system will be simple if thats whats needed.

Polyurethane of the two-part type are commonly used for casting limited
quantities of plastic parts. Rigid and flexible are available for
making both molds and casts. Some have fillers, some are fast to cure,
some are slow to cure, etc. Here is a link to one of a multitude of
suppliers: http://www.smooth-on.com. They have an informative site with
sufficient information to get you started.

As to injection molding, thermoplastic resins like polystyrene, need to
be heated uniformly, and not overheated or held to long at their
processing temperature, which might resemble cold honey, not very
pourable. Most recylable plastic products have a recycle symbol
somewhere with a number or abriviation like PS for polystyrene. Good
luck with your project.
--
Billy Hiebert
HIEBERT SCULPTURE WORKS
Small Part Injection Molding
http://www.hieberts.com

For ease of use, would plaster of Paris do?

Jordan

HotRod wrote:
I want to cast some basic copies of parts and then make some additions and
changes to the plastic mold. I will then re-cast a negative mold to create
the metal part.

Jordan wrote:
For ease of use, would plaster of Paris do?

Jordan

HotRod wrote:

I want to cast some basic copies of parts and then make some additions
and changes to the plastic mold. I will then re-cast a negative mold
to create the metal part.

So you already have a plastic mold? If so, does it have proper draft so
that the rigid cast can be removed? Will plaster have sufficient
strength for the type of part to be cast?
--
Billy Hiebert
HIEBERT SCULPTURE WORKS
Small Part Injection Molding
http://www.hieberts.com

you might look at the hot-melt glues. Some have "fibers" in them and
others don't. Those without would probably be prefered. A good release
agent would be required.

Hul


HotRod wrote:
Does anyone know of a plastic that I can buy at my local hardware store that
I would be able to melt and pour into a mould? I just want to practice and
create a few parts from plastic before I try and use metal?

daniel peterman wrote:
You could use hot melt glue. Or polyester resin or even acrylic resin
dust from sawing sheets of plexiglas. disolve it in methylene chloride.
Easiest is the polyester resin. I did itwhen I was twelve years old



------------------------------------------------------------------------

Till the Next Time

I'm just wondering, but not offended. I noticed there was this little
bit of HTML coding in your post:

*******************

htmlbody bgcolor=darkcyanfont color=alicebluefont size=5font
effect=shadowblackfaceTill the Next Time/blackface/html

*******************

And I wondered how it made it to my news client (Netscape 7.2) so that
it did its thing.

I thought that newsgroup processing somehow stripped off any HTML code.

My inquiring mind wants to know...

Thanks,

Jeff

--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)

"Truth exists; only falsehood has to be invented."

Check out this on my homepage.

http://www.gardenofwar.gq.nu/CASTING...ics/Page4.html

According to Jeff Wisnia :
daniel peterman wrote:

[ ... ]

I'm just wondering, but not offended. I noticed there was this little
bit of HTML coding in your post:

*******************

htmlbody bgcolor=darkcyanfont color=alicebluefont size=5font
effect=shadowblackfaceTill the Next Time/blackface/html

*******************

And I wondered how it made it to my news client (Netscape 7.2) so that
it did its thing.

I thought that newsgroup processing somehow stripped off any HTML code.

Some news servers toss into the bit bucket anything with *any*
kind of attachments. (And yes, HTML *is* an attachment.)

Others (most) do not.

So -- what you see is a function of which news servers it has
had to pass through.

Those that toss are likely to toss the whole article, instead of
trying to clean it up.

This makes it better for anyone to make sure that their news
articles have *no* HTML in them, so they reach the maximum number of
possible readers.

And -- you are safer (from virus infections) using a newsreader
which does not even *understand* HTML, so it can't process it. HTLM
processing makes it possible to hide nasties.

Enjoy,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

This is a TEXT by definition news group - as many users are in various I/O connections.

Some actually pay - or once paid by KB downloaded. So text was mandated.

Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder



Jeff Wisnia wrote:
daniel peterman wrote:

You could use hot melt glue. Or polyester resin or even acrylic resin
dust from sawing sheets of plexiglas. disolve it in methylene chloride.
Easiest is the polyester resin. I did itwhen I was twelve years old



------------------------------------------------------------------------

Till the Next Time


I'm just wondering, but not offended. I noticed there was this little
bit of HTML coding in your post:

*******************

htmlbody bgcolor=darkcyanfont color=alicebluefont size=5font
effect=shadowblackfaceTill the Next Time/blackface/html

*******************

And I wondered how it made it to my news client (Netscape 7.2) so that
it did its thing.

I thought that newsgroup processing somehow stripped off any HTML code.

My inquiring mind wants to know...

Thanks,

Jeff


----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

actually Eastwood Company sells a kit that you can make your own plastic
parts from a 2 part plastic ,anything from car emblems to shift knobs
and anything you can come up with ,and the plastic is very durable.

Sorry I misread what the poster had said but wax is a good way of trying
out pouring a mould and allot more affordable ,even the high end machine
shops are using wax to use as a way to machine a part without the
expense of using a piece of metal and if it's wrong and don't work you
can remelt it and try again,with wax once you find out something is
going to come out right ,you just remelt it and use it again next time
you need to do a test part.
Just an added note ancient romans used to use wax to make bronze items
with very intricate designs ,what they did was they made the item from
wax with all the design work on it
and since it was softer it was allot easier to make the most intricate
details on the surface
then they would take the wax plug and cover it in clay and then cure it
in the air til it dries then they put it in an oven to harden it and
melt the wax which I believe they turned it upside down to let all the
wax drain out then they took it and poured the molten bronze into the
mold and after it was done they just broke the material away and they
would have an excellent piece of art whether it be a helmet or a pitcher
or just ornate decoration or jewelry ,which they still use this method
in mexico or spain in some jewelry shops that make custom pieces but
they use plaster of paris instead of clay.
Good luck and have fun

On Mon, 9 Jan 2006 14:32:50 -0500, "HotRod"
wrote:

Does anyone know of a plastic that I can buy at my local hardware store that
I would be able to melt and pour into a mould? I just want to practice and
create a few parts from plastic before I try and use metal?

Sorry, no. Metal is dense, plastic isn't. So moulds designed for
gravity-poured metal just won't fill properly when used for plastic. I
don't see this "practice" approach as really telling you that much
useful. IMHO you'd be better of making some simple pours with the same
techniques and materials you're planning to use in the end.

Bronze into lost foam/sand is a good metal casting technique to begin
with.

WOW, thanks for all of the replies. I think for now I'm going to start with
plaster of Paris to make some molds and then try some plastic. I have a few
plastic parts that I actually want to make so they will never be converted
to metal. Thank you for all of the ideas, I'd like to try and find some
local plastic at my hardware store that can be melted and injected so that I
can just run down the street and get more if needed. But first I need to
work on some ventilation.

Sorry Jeff
That's a sig line I usually drop when posting to newsgroups. I musta
fergot this time

daniel peterman wrote:

Sorry Jeff
That's a sig line I usually drop when posting to newsgroups. I musta
fergot this time


No offense taken Dan, I was just curious.

The responses seem to once again bear out that there's no 100 percent
certainty about much of anything on the internet. G

Jeff

--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)

"Truth exists; only falsehood has to be invented."

HotRod wrote:

... Making an injection
system will be simple if thats whats needed.

Famous last words, as we used to say. "Simple" is all relative to ones
abilities & experience. For me, making an injection molding system is
probably possible, but certainly not simple. YMMV.

Lindsay (Lindsy, Linds... ??) Publishing has a DIY molding system book
by Dave Gingery, if you do decide to go that route.

Bob

"DoN. Nichols" wrote:



Some news servers toss into the bit bucket anything with *any*
kind of attachments. (And yes, HTML *is* an attachment.)

HTML is *not* an attachment. HTML may reference an attachment or an
external site, but HTML *is* plain text.

Pete C.

According to Pete C. :
"DoN. Nichols" wrote:



Some news servers toss into the bit bucket anything with *any*
kind of attachments. (And yes, HTML *is* an attachment.)

HTML is *not* an attachment. HTML may reference an attachment or an
external site, but HTML *is* plain text.

An HTML copy of the text in the article is a separate mime
attachment. It may be plain text, but newsreaders need a way to
distinguish between the HTML and the plain text. My current newsreader
suppresses display of the HTML copy, focusing on the plain text.

And "vcards" (Microsoft's re-invention of the .sig block) tend
to have such mime wrappers.

Now -- it is *possible* to put a chunk of HTML in the middle of
an article in plan text without such a wrapper. In an HTML capable
newsreader, it will do what it was designed to do (which may or may not
be what you would like it to do). In a plain-text-only newsreader, it
will simply look ugly.

Enjoy,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

I've created text pages left and right with ed and Emacs creating web pages
for Mosaic and Netscape.
Lot of cut an paste. Now a little more complex.
But still text. Tools see it and translate. Just like Gerber - the right tool and ...
Or postscript file - I have the manual. Wonderful graphic language set.


Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder



Pete C. wrote:
"DoN. Nichols" wrote:




Some news servers toss into the bit bucket anything with *any*
kind of attachments. (And yes, HTML *is* an attachment.)


HTML is *not* an attachment. HTML may reference an attachment or an
external site, but HTML *is* plain text.

Pete C.

----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----