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In lugnet.technic, Jason S. Mantor writes:
> The first one you cite is probably the right one for LEGO(R) Bricks.
> They're molded, not extruded and I don't believe they are impact grade.
They're clearly not extruded... that's the kind Plastruct(R) uses.
But if they're just plain molded and not impact grade I am hoping they are
from the higher end of the range. The low end mold temp (and I agree with
Thomas Avery's speculations about what it means although my molding
experience is with aluminium) of 109 scares me... it gets that hot in the
south (or in attics) on a regular basis.
HOWEVER, mold temp MAY mean the temperature you should heat the mold to for
best results... I dunno. But I know that the aluminium targeted molds I saw
were heated to 4-500 degrees Farenheit before the molt was introduced.
Regardless, LEGO(r) will discolor if not actually deform well below boiling
temps, I discolored some LEGO by putting it in a dishwasher.
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In lugnet.technic, Larry Pieniazek writes:
> They're clearly not extruded... that's the kind Plastruct(R) uses.
>
> But if they're just plain molded and not impact grade I am hoping they are
> from the higher end of the range. The low end mold temp (and I agree with
> Thomas Avery's speculations about what it means although my molding
> experience is with aluminium) of 109 scares me... it gets that hot in the
> south (or in attics) on a regular basis.
I measured the temp in my attic last summer and it reached 115 F. Needless
to say I don't keep much up there and definitely not my Lego collection!
ROSCO had a bad "melting" experience:
http://www.brickshelf.com/cgi-bin/gallery.cgi?i=42127
I think this was caused by prolonged exposure to direct sunlight, but I
forgot what he had said about it.
TJ
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In lugnet.technic, Thomas Avery writes:
> In lugnet.technic, Larry Pieniazek writes:
> > They're clearly not extruded... that's the kind Plastruct(R) uses.
> >
> > But if they're just plain molded and not impact grade I am hoping they are
> > from the higher end of the range. The low end mold temp (and I agree with
> > Thomas Avery's speculations about what it means although my molding
> > experience is with aluminium) of 109 scares me... it gets that hot in the
> > south (or in attics) on a regular basis.
>
> I measured the temp in my attic last summer and it reached 115 F. Needless
> to say I don't keep much up there and definitely not my Lego collection!
>
> ROSCO had a bad "melting" experience:
> http://www.brickshelf.com/cgi-bin/gallery.cgi?i=42127
>
> I think this was caused by prolonged exposure to direct sunlight, but I
> forgot what he had said about it.
IIRC, I thought it was from the back shelf of a car... cars with no windows
opened can easily get to 145 or even hotter. (hence the warnings about not
leaving dogs or ferrets or cats or whatever locked in cars on sunny days, it
will kill them)
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If you would just put your bricks in the kitchen oven you would make rapid
progress with this question.
Better yet, obtain a laboratory hot plate with fine temperature control and
put a brick between two slides with a weight on top. Do this at several
temperatures and observe the rate of deformation.
As a crude experiment, chop up a brick and pack it into a small crucible.
You should be able to fuse the particles in a kitchen oven at about 500 F,
but without applied pressure they will be easy to pull apart again.
Remember, experience without theory teaches nothing, so look up those terms
after you've been forbidden to put any more objects in the oven.
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In lugnet.technic, Erik Olson writes:
> If you would just put your bricks in the kitchen oven you would make rapid
> progress with this question.
I am in total agreement with this, including the 'you' (as long as it's not
'me'... advancement of science is fine but I ain't putting my bricks in no
oven thank you)
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In lugnet.technic, Larry Pieniazek writes:
> In lugnet.technic, Erik Olson writes:
> > If you would just put your bricks in the kitchen oven you would make rapid
> > progress with this question.
>
> I am in total agreement with this, including the 'you' (as long as it's not
> 'me'... advancement of science is fine but I ain't putting my bricks in no
> oven thank you)
Yes, I can see how this would help the progress of scientific knowledge, but
realize that technic pieces are hard to come by in the first place these
days.. you cannot walk into your local toystore and pick up a supercar...
that I'll take the pure conjecture that LEGO bricks melt at high
temperatures and not actually research this myself to see if it's true.
For once I'll believe the axiom without trying to prove it myself.
Dave
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In lugnet.technic, Thomas Avery writes:
> In lugnet.technic, Larry Pieniazek writes:
> > They're clearly not extruded... that's the kind Plastruct(R) uses.
> >
> > But if they're just plain molded and not impact grade I am hoping they are
> > from the higher end of the range. The low end mold temp (and I agree with
> > Thomas Avery's speculations about what it means although my molding
> > experience is with aluminium) of 109 scares me... it gets that hot in the
> > south (or in attics) on a regular basis.
>
> I measured the temp in my attic last summer and it reached 115 F. Needless
> to say I don't keep much up there and definitely not my Lego collection!
>
> ROSCO had a bad "melting" experience:
> http://www.brickshelf.com/cgi-bin/gallery.cgi?i=42127
>
> I think this was caused by prolonged exposure to direct sunlight, but I
> forgot what he had said about it.
>
> TJ
That reminds me of a picture I just took in December at Legoland - the Grand
Central Station in Miniland had an amazing bit of damage due to sunlight!
Check it out at http://www.brickshelf.com/cgi-bin/gallery.cgi?i=132159 (big
file - sorry) - look in the bottom right corner of the 'window' where people
are getting on the escalator. First you'll see that the reflection of the
clear plastic window has significantly 'boiled' the bricks below, (okay, I
know it didn't physically boil, but it looks like it!) and you'll also see
that the wall has shrunk to such a point that it detached and bowed.
--
David Schilling
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In lugnet.technic, Larry Pieniazek writes:
> In lugnet.technic, Jason S. Mantor writes:
> > The first one you cite is probably the right one for LEGO(R) Bricks.
> > They're molded, not extruded and I don't believe they are impact grade.
>
> They're clearly not extruded... that's the kind Plastruct(R) uses.
>
> But if they're just plain molded and not impact grade I am hoping they are
> from the higher end of the range. The low end mold temp (and I agree with
> Thomas Avery's speculations about what it means although my molding
> experience is with aluminium) of 109 scares me... it gets that hot in the
> south (or in attics) on a regular basis.
My guess would be 109C may be more likely - I'd be surprised if they could mold
it at 109F. I'm guessing my bad experience with the heater was well over 109F
(they were quite close to it), and they didn't "flow" anywhere near enough that
I'd expect they'd need for molding.
> HOWEVER, mold temp MAY mean the temperature you should heat the mold to for
> best results... I dunno. But I know that the aluminium targeted molds I saw
> were heated to 4-500 degrees Farenheit before the molt was introduced.
>
> Regardless, LEGO(r) will discolor if not actually deform well below boiling
> temps, I discolored some LEGO by putting it in a dishwasher.
And you can see the discolouration in bricks left outside for prolonged
periods, though this may also be related to light exposure. Just look closely
at the Legoland models 8?)
ROSCO
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IIRC, ABS is a thermoset plastic. The first time you melt it it's workable
at a relatively low temp and solidifies nicely, but heating it again won't
melt it, only deform it and finally burn it : (
-Xanthra47
Ross Crawford <rcrawford@csi.com> wrote in message
news:GsIupy.Kv9@lugnet.com...
> My guess would be 109C may be more likely - I'd be surprised if they could • mold
> it at 109F. I'm guessing my bad experience with the heater was well over • 109F
> (they were quite close to it), and they didn't "flow" anywhere near enough • that
> I'd expect they'd need for molding.
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In lugnet.technic, Jason S. Mantor writes:
> IIRC, ABS is a thermoset plastic. The first time you melt it it's workable
> at a relatively low temp and solidifies nicely, but heating it again won't
> melt it, only deform it and finally burn it : (
That explains it. And it smells pretty bad too - that's what alerted me when I
had my "accident".
ROSCO
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In lugnet.technic, Jason S. Mantor writes:
> IIRC, ABS is a thermoset plastic.
No, it's thermoplastic. But too much heat, or even localized hot spots, can
scorch it and make it unusable.
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