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Machinable Thermal Insulator Good to > 500F?
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Doug White
Dec 7, 2012, 6:31:25 PM12/7/12
to
I am making an annealing "oven" for nylon rod out of a piece of 4" stove
pipe wrapped in fiberglass insulation. The rods will be suspecded
vetically in the pipe, and it will be heated with a heat gun from the
bottom. Nylon anneals at ~ 350F, but the termperature will be a bit
uneven, so places may get a good bit hotter.
BEFORE EVERYONE GOES OFF ON A TANGENT ABOUT 16 DIFFERENT WAYS TO DO THIS,
DON'T BOTHER. THAT'S NOT MY QUESTION. (Sorry, but I'm tired of everyone
trying to ignore my actual question in favor of redesigning _everything_.
I've had a cold for days, and I'm a bit testy..).
I will support the pipe from the side with a chemical ring stand setup.
To minimize the heat lost through the suspension system, I need something
that is a good thermal insulator to go between the 1/2" diameter metal
support rods and the stove pipe. My default will be threaded ceramic
spacers, which I can pick up from Mcmaster Carr, but they are over $4
each. Not fatal by any means, but mildly annoying.
If I knew of a good insulating material that could take the heat, I could
machine the spacers myself, but the only plastic I'm aware of that is
good to higher temps is teflon, but McMaster says it is JUST good to
500F. It's also not the best material from a mechanical rigidity
standpoint. I have some & might try it, but I was wondering if there was
some material that I'm overlooking.
Thanks for comments & ideas.
Doug White
pipe wrapped in fiberglass insulation. The rods will be suspecded
vetically in the pipe, and it will be heated with a heat gun from the
bottom. Nylon anneals at ~ 350F, but the termperature will be a bit
uneven, so places may get a good bit hotter.
BEFORE EVERYONE GOES OFF ON A TANGENT ABOUT 16 DIFFERENT WAYS TO DO THIS,
DON'T BOTHER. THAT'S NOT MY QUESTION. (Sorry, but I'm tired of everyone
trying to ignore my actual question in favor of redesigning _everything_.
I've had a cold for days, and I'm a bit testy..).
I will support the pipe from the side with a chemical ring stand setup.
To minimize the heat lost through the suspension system, I need something
that is a good thermal insulator to go between the 1/2" diameter metal
support rods and the stove pipe. My default will be threaded ceramic
spacers, which I can pick up from Mcmaster Carr, but they are over $4
each. Not fatal by any means, but mildly annoying.
If I knew of a good insulating material that could take the heat, I could
machine the spacers myself, but the only plastic I'm aware of that is
good to higher temps is teflon, but McMaster says it is JUST good to
500F. It's also not the best material from a mechanical rigidity
standpoint. I have some & might try it, but I was wondering if there was
some material that I'm overlooking.
Thanks for comments & ideas.
Doug White
Jon Elson
Dec 7, 2012, 6:56:05 PM12/7/12
to
Doug White wrote:
>
> If I knew of a good insulating material that could take the heat, I could
> machine the spacers myself, but the only plastic I'm aware of that is
> good to higher temps is teflon, but McMaster says it is JUST good to
> 500F. It's also not the best material from a mechanical rigidity
> standpoint. I have some & might try it, but I was wondering if there was
> some material that I'm overlooking.
Raw Teflon moldings are sintered at 350 C (Note the C). So, Teflon is
>
> If I knew of a good insulating material that could take the heat, I could
> machine the spacers myself, but the only plastic I'm aware of that is
> good to higher temps is teflon, but McMaster says it is JUST good to
> 500F. It's also not the best material from a mechanical rigidity
> standpoint. I have some & might try it, but I was wondering if there was
> some material that I'm overlooking.
almost loafing at 500F. It does get a bit soft above 300 C, but 500 F is
only 260 C - nowhere near the breakdown temp. I tried to make a very
complex Teflon molded piece some years ago, but was not able to fill the
mold uniformly, so the parts were misshapen when they came out of the
sintering oven. But, I got some experience with Teflon at high
temperatures.
Jon
anorton
Dec 7, 2012, 7:03:23 PM12/7/12
to
"Doug White" <gwh...@alum.mit.edu> wrote in message
news:XnsA122BC8907524...@69.16.186.7...
Can you cast cement into the correct shape? Embed nuts if you need threads
at the ends. Mix in shredded fiber glass for extra bending strength if
needed. Can you do something with glass tubing? Use something like thinset
tile cement to bond nuts in place if needed. You can also make pretty decent
thermal insulators from a piece of stainless steel that has a narrow
cross-section at some point.
mike
Dec 7, 2012, 7:24:23 PM12/7/12
to
Carl Ijames
Dec 7, 2012, 6:47:19 PM12/7/12
to
Fairly loosely crumpled balls of aluminum foil, 1" od or so, if that fits.
Use three to wedge the pipe into the ring. Conduction won't be nearly as
bad as you think, and the price is right.
-----
Regards,
Carl Ijames
"Doug White" wrote in message
news:XnsA122BC8907524...@69.16.186.7...
Use three to wedge the pipe into the ring. Conduction won't be nearly as
bad as you think, and the price is right.
-----
Regards,
Carl Ijames
"Doug White" wrote in message
news:XnsA122BC8907524...@69.16.186.7...
DoN. Nichols
Dec 7, 2012, 7:46:50 PM12/7/12
to
On 2012-12-07, Doug White <gwh...@alum.mit.edu> wrote:
> I am making an annealing "oven" for nylon rod out of a piece of 4" stove
> pipe wrapped in fiberglass insulation. The rods will be suspecded
> vetically in the pipe, and it will be heated with a heat gun from the
> bottom. Nylon anneals at ~ 350F, but the termperature will be a bit
> uneven, so places may get a good bit hotter.
[ ... ]
> I am making an annealing "oven" for nylon rod out of a piece of 4" stove
> pipe wrapped in fiberglass insulation. The rods will be suspecded
> vetically in the pipe, and it will be heated with a heat gun from the
> bottom. Nylon anneals at ~ 350F, but the termperature will be a bit
> uneven, so places may get a good bit hotter.
> I will support the pipe from the side with a chemical ring stand setup.
> To minimize the heat lost through the suspension system, I need something
> that is a good thermal insulator to go between the 1/2" diameter metal
> support rods and the stove pipe. My default will be threaded ceramic
> spacers, which I can pick up from Mcmaster Carr, but they are over $4
> each. Not fatal by any means, but mildly annoying.
I'm not that sure about its thermal insulation properties.
> If I knew of a good insulating material that could take the heat, I could
> machine the spacers myself, but the only plastic I'm aware of that is
> good to higher temps is teflon, but McMaster says it is JUST good to
> 500F. It's also not the best material from a mechanical rigidity
> standpoint. I have some & might try it, but I was wondering if there was
> some material that I'm overlooking.
can machine yourself, have you looked at "lava" (Alumina Silicate
L911A). You machine it and then fire it, and it turns from a gray
machinable material to a pink material which you can't touch with any
metal tools. Here is a site about it:
<http://www.professionalplastics.com/LAVAa>
(And no, it is *not* a plastic. :-) It is fired at 1850º and 2000º F
(sorry if the degrees symbol does not come out right on your computer.
On mine, it is an underlined superscript '0', but it is what I got with
cut-and-paste from the web page. Based on the color, it is used to make
the "gas lens" for TIG welding guns.
No -- I don't know what it costs, but the $4.00 each ones from
McMaster Carr may be affordable by comparison -- especially if you don't
have the ability to fire it already at hand.
Enjoy,
DoN.
--
Remove oil spill source from e-mail
Email: <BPdnic...@d-and-d.com> | 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 ---
Doug White
Dec 7, 2012, 7:56:12 PM12/7/12
to
"Carl Ijames" <carl.delt...@verizon.net> wrote in
news:k9u1s...@news6.newsguy.com:
> Fairly loosely crumpled balls of aluminum foil, 1" od or so, if that
> fits. Use three to wedge the pipe into the ring. Conduction won't be
> nearly as bad as you think, and the price is right.
I was thinking of something smallish I can easliy run through the
fiberglass, which is already tubular, but it might work.
Hmm. I suspect three springs would also provide similar thermal isolation,
especially if they were stainless.
Food for thought...
Thanks!
Doug White
news:k9u1s...@news6.newsguy.com:
> Fairly loosely crumpled balls of aluminum foil, 1" od or so, if that
> fits. Use three to wedge the pipe into the ring. Conduction won't be
> nearly as bad as you think, and the price is right.
fiberglass, which is already tubular, but it might work.
Hmm. I suspect three springs would also provide similar thermal isolation,
especially if they were stainless.
Food for thought...
Thanks!
Doug White
Doug White
Dec 7, 2012, 7:59:27 PM12/7/12
to
Jon Elson <jme...@wustl.edu> wrote in
news:z86dnUXayJxx4l_N...@giganews.com:
I _thought_ Teflon would handle it, but I was a bit surprised to see
McMaster only rated it to 500F. They don't exactly say what parameter
degrades by what amount to determine that, so it sounds like it would be
OK.
Given that I have some on hand, that's probably the place to start.
Thanks!
Doug White
news:z86dnUXayJxx4l_N...@giganews.com:
McMaster only rated it to 500F. They don't exactly say what parameter
degrades by what amount to determine that, so it sounds like it would be
OK.
Given that I have some on hand, that's probably the place to start.
Thanks!
Doug White
Doug White
Dec 7, 2012, 8:17:15 PM12/7/12
to
"DoN. Nichols" <BPdnic...@d-and-d.com> wrote in
news:slrnkc53fo.l4...@Katana.d-and-d.com:
I did a little digging. Steatite ceramic is the off white stuff
typically used in electrical insulators. It has 1/8th the thermal
conductivity of stainless steel. However, teflon is a factor of 8 better
than Steatite, so that looks like the winner.
Doug White
news:slrnkc53fo.l4...@Katana.d-and-d.com:
typically used in electrical insulators. It has 1/8th the thermal
conductivity of stainless steel. However, teflon is a factor of 8 better
than Steatite, so that looks like the winner.
Doug White
dca...@krl.org
Dec 7, 2012, 8:25:39 PM12/7/12
to
On Dec 7, 6:31 pm, Doug White <gwh...@alum.mit.edu> wrote:
> If I knew of a good insulating material that could take the heat, I could
> machine the spacers myself, but the only plastic I'm aware of that is
> good to higher temps is teflon, but McMaster says it is JUST good to
> 500F. It's also not the best material from a mechanical rigidity
> standpoint. I have some & might try it, but I was wondering if there was
> some material that I'm overlooking.
>
> Thanks for comments & ideas.
>
> Doug White
I think Teflon generates Phosgene when over heated. So not something
> If I knew of a good insulating material that could take the heat, I could
> machine the spacers myself, but the only plastic I'm aware of that is
> good to higher temps is teflon, but McMaster says it is JUST good to
> 500F. It's also not the best material from a mechanical rigidity
> standpoint. I have some & might try it, but I was wondering if there was
> some material that I'm overlooking.
>
> Thanks for comments & ideas.
>
> Doug White
I would use.
Vermiculite and Perlite mixed with portland cement is one
possibility.
Or mixed with Waterglass ( Sodium Silicate ).
Or insulating fire brick.
Or look at the A.P. Green catalog for castable refractories.
Your local hardware store probably has furnace cement.
Dan
Jim Wilkins
Dec 7, 2012, 10:13:49 PM12/7/12
to
"Doug White" <gwh...@alum.mit.edu> wrote in message
news:XnsA122BC8907524...@69.16.186.7...
Could you suspend the ring with fiberglass thread taken from an auto
body patch?
Spark plugs are ceramic insulators and some have threads on both ends.
jsw
news:XnsA122BC8907524...@69.16.186.7...
>I am making an annealing "oven" for nylon rod out of a piece of 4"
>stove
> pipe wrapped in fiberglass insulation.
>
> Doug White
>stove
> pipe wrapped in fiberglass insulation.
>
Could you suspend the ring with fiberglass thread taken from an auto
body patch?
Spark plugs are ceramic insulators and some have threads on both ends.
jsw
Spehro Pefhany
Dec 7, 2012, 10:53:42 PM12/7/12
to
$8.77 for 1'
Thermal conductivity of Ti is 22 W*m^-1* K-1
Cross sectional area is (6.35^2-5.461^2)* pi = 33mm^2 = 3.3E-5m^2
Thermal conductivity of the tube is 7.3E-4 W*m*K-1
Say 50mm pieces = 0.05m
Say 250°C difference
Heat flow is 7.3E-4 * 250 / 0.05 W = 3.65W
Four pieces will conduct about 15W
Not bad, IMHO, only 1% of a 1500W heat gun.
Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
sp...@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
Steve W.
Dec 8, 2012, 3:48:55 AM12/8/12
to
of a clay flower pot?
Or get a couple of fire bricks and cut and form them as needed. The ones
I used to line my melting furnace could be cut and shaped easily with
common woodworking tools.
--
Steve W.
Spuckle
Dec 8, 2012, 8:31:46 AM12/8/12
to
Bob Engelhardt
Dec 8, 2012, 9:20:14 AM12/8/12
to
'Twere me, I wouldn't worry about it - I'd just use bolts. Given that
you're using a heat gun and not heating elements, _most_ of the heat is
going to be blown out the exhaust anyhow. Even if you used elements and
sealed it up, I don't think that the loss through the supports is worth
worrying about.
Bob
you're using a heat gun and not heating elements, _most_ of the heat is
going to be blown out the exhaust anyhow. Even if you used elements and
sealed it up, I don't think that the loss through the supports is worth
worrying about.
Bob
Spehro Pefhany
Dec 8, 2012, 9:29:37 AM12/8/12
to
reasonable size won't be all that significant.
I'm not a big fan of Macor.
Doug White
Dec 8, 2012, 10:10:42 AM12/8/12
to
"Jim Wilkins" <murat...@gmail.com> wrote in news:k9ucbl$s0l$1@dont-
email.me:
Now that is thinking out of the box! I'll probably stick with Teflon, but
that is a very clever idea.
Doug White
email.me:
that is a very clever idea.
Doug White
Doug White
Dec 8, 2012, 10:17:52 AM12/8/12
to
"dca...@krl.org" <dca...@krl.org> wrote in
news:c602d309-6e88-4e24...@4g2000yqv.googlegroups.com:
> On Dec 7, 6:31 pm, Doug White <gwh...@alum.mit.edu> wrote:
>
>> If I knew of a good insulating material that could take the heat, I
>> could machine the spacers myself, but the only plastic I'm aware of
>> that is good to higher temps is teflon, but McMaster says it is JUST
>> good to 500F. It's also not the best material from a mechanical
>> rigidity standpoint. I have some & might try it, but I was wondering
>> if there w
> as
>> some material that I'm overlooking.
>>
>> Thanks for comments & ideas.
>>
>> Doug White
>
> I think Teflon generates Phosgene when over heated. So not something
> I would use.
High molecular weight Teflon only does that above about ~800F. I
shouldn't get anywhere near that hot. Low molecular weight Teflon can
give off fumes that kill birds down around 375F. I am a featherless
biped, with much larger mass, but I may run this where there is at least
a little ventilation to be safe.
Doug White
news:c602d309-6e88-4e24...@4g2000yqv.googlegroups.com:
> On Dec 7, 6:31 pm, Doug White <gwh...@alum.mit.edu> wrote:
>
>> If I knew of a good insulating material that could take the heat, I
>> could machine the spacers myself, but the only plastic I'm aware of
>> that is good to higher temps is teflon, but McMaster says it is JUST
>> good to 500F. It's also not the best material from a mechanical
>> rigidity standpoint. I have some & might try it, but I was wondering
>> if there w
> as
>> some material that I'm overlooking.
>>
>> Thanks for comments & ideas.
>>
>> Doug White
>
> I think Teflon generates Phosgene when over heated. So not something
> I would use.
shouldn't get anywhere near that hot. Low molecular weight Teflon can
give off fumes that kill birds down around 375F. I am a featherless
biped, with much larger mass, but I may run this where there is at least
a little ventilation to be safe.
Doug White
Doug White
Dec 8, 2012, 10:23:25 AM12/8/12
to
Spehro Pefhany <spef...@interlogDOTyou.knowwhat> wrote in
news:efj6c8dtuqttf4f1k...@4ax.com:
> On Sat, 08 Dec 2012 09:20:14 -0500, the renowned Bob Engelhardt
> <bobeng...@comcast.net> wrote:
>
>>'Twere me, I wouldn't worry about it - I'd just use bolts. Given that
>>you're using a heat gun and not heating elements, _most_ of the heat is
>>going to be blown out the exhaust anyhow. Even if you used elements
and
>>sealed it up, I don't think that the loss through the supports is worth
>>worrying about.
>>
>>Bob
>
> I think you're right- heat loss through SS bolts, rods or tubes of
> reasonable size won't be all that significant.
>
> I'm not a big fan of Macor.
Rather than making a completely insulating threaded Teflon spacer, I may
start with a 6-32 SS screw & a Teflon washer. I don't actually have true
ring stand rings at this point, just rods & clamps. I was planning on
just running a 1/2" rod out from a clamp, with a screw in the end through
the stove pipe. The heat flow would be from the pipe to the end of the
rod.
Doug White
news:efj6c8dtuqttf4f1k...@4ax.com:
> On Sat, 08 Dec 2012 09:20:14 -0500, the renowned Bob Engelhardt
> <bobeng...@comcast.net> wrote:
>
>>'Twere me, I wouldn't worry about it - I'd just use bolts. Given that
>>you're using a heat gun and not heating elements, _most_ of the heat is
>>going to be blown out the exhaust anyhow. Even if you used elements
and
>>sealed it up, I don't think that the loss through the supports is worth
>>worrying about.
>>
>>Bob
>
> I think you're right- heat loss through SS bolts, rods or tubes of
> reasonable size won't be all that significant.
>
> I'm not a big fan of Macor.
start with a 6-32 SS screw & a Teflon washer. I don't actually have true
ring stand rings at this point, just rods & clamps. I was planning on
just running a 1/2" rod out from a clamp, with a screw in the end through
the stove pipe. The heat flow would be from the pipe to the end of the
rod.
Doug White
axolotl
Dec 8, 2012, 10:29:14 AM12/8/12
to
<http://www.foamglas.us/building/products/product_overview/foamglas_slabs/>
Kevin Gallimore
Carl Ijames
Dec 8, 2012, 12:17:11 PM12/8/12
to
So skip the washer and use SS tubing for the rod and wrap the first couple
of inches with insulation before it reaches the clamp. Slit and fold the
end over to make a vertical tab for the screw to go through with a nut on
the backside, and put a cork in the cold end to limit internal convection
losses. I guess one thing we don't know is if this is a one-use lash up or
something to be used for a long time that needs to be efficient and sturdy.
I'm assuming few uses, or else you'd wrap the tube with heating tape under
the insulation for a more uniform temp distribution, but you said we weren't
allowed to start redesigning that part :-) :-).
-----
Regards,
Carl Ijames
"Doug White" wrote in message
news:XnsA12369BA39390...@69.16.186.7...
of inches with insulation before it reaches the clamp. Slit and fold the
end over to make a vertical tab for the screw to go through with a nut on
the backside, and put a cork in the cold end to limit internal convection
losses. I guess one thing we don't know is if this is a one-use lash up or
something to be used for a long time that needs to be efficient and sturdy.
I'm assuming few uses, or else you'd wrap the tube with heating tape under
the insulation for a more uniform temp distribution, but you said we weren't
allowed to start redesigning that part :-) :-).
-----
Regards,
Carl Ijames
"Doug White" wrote in message
James Waldby
Dec 8, 2012, 1:45:36 PM12/8/12
to
On Sat, 08 Dec 2012 15:23:25 +0000, Doug White wrote:
> Spehro Pefhany wrote ...
<http://www.weldfabulous.com/p-27700-weldcraft-13n08-nozzle-alumina-4-14-pkg-10.aspx>
which is $13.54 for 10-pack. Some other sizes cost less on ebay, eg:
<http://www.ebay.com/itm/10pcs-13N08-4-Alumina-Shield-Cup-TIG-Welding-torch-Nozzle-WP-9-20-25-/180933453159?pt=LH_DefaultDomain_0&hash=item2a20796567>
--
jiw
> Spehro Pefhany wrote ...
>> On Sat, 08 Dec 2012 09:20:14 -0500, Bob Engelhardt wrote:
>>
>>>'Twere me, I wouldn't worry about it - I'd just use bolts. Given that
>>>you're using a heat gun and not heating elements, _most_ of the heat is
>>>going to be blown out the exhaust anyhow. Even if you used elements
>>>and sealed it up, I don't think that the loss through the supports is
>>>worth worrying about.
>>
>>
>>>'Twere me, I wouldn't worry about it - I'd just use bolts. Given that
>>>you're using a heat gun and not heating elements, _most_ of the heat is
>>>going to be blown out the exhaust anyhow. Even if you used elements
>>>and sealed it up, I don't think that the loss through the supports is
>>>worth worrying about.
>>
>> I think you're right- heat loss through SS bolts, rods or tubes of
>> reasonable size won't be all that significant.
>> I'm not a big fan of Macor.
>
> Rather than making a completely insulating threaded Teflon spacer, I may
> start with a 6-32 SS screw & a Teflon washer. I don't actually have true
> ring stand rings at this point, just rods & clamps. I was planning on
> just running a 1/2" rod out from a clamp, with a screw in the end through
> the stove pipe. The heat flow would be from the pipe to the end of the
> rod.
Also consider tig torch nozzles as ceramic spacers, eg see
>> reasonable size won't be all that significant.
>> I'm not a big fan of Macor.
>
> Rather than making a completely insulating threaded Teflon spacer, I may
> start with a 6-32 SS screw & a Teflon washer. I don't actually have true
> ring stand rings at this point, just rods & clamps. I was planning on
> just running a 1/2" rod out from a clamp, with a screw in the end through
> the stove pipe. The heat flow would be from the pipe to the end of the
> rod.
<http://www.weldfabulous.com/p-27700-weldcraft-13n08-nozzle-alumina-4-14-pkg-10.aspx>
which is $13.54 for 10-pack. Some other sizes cost less on ebay, eg:
<http://www.ebay.com/itm/10pcs-13N08-4-Alumina-Shield-Cup-TIG-Welding-torch-Nozzle-WP-9-20-25-/180933453159?pt=LH_DefaultDomain_0&hash=item2a20796567>
--
jiw
whit3rd
Dec 8, 2012, 4:28:29 PM12/8/12
to
On Friday, December 7, 2012 3:31:25 PM UTC-8, Doug White wrote:
> I am making an annealing "oven" for nylon ...
pipe and clamp jaws, and use of tough but thin metal (brazed stainless
steel?) to make support brackets for the pipe.
Fiberglass is easily available (auto body repair stocks), and two inches of
thin metal should easily bridge from a hot pipe to a hold-in-your-hand
half inch rod.
You might also consider double-wall pipe, to control heat loss,
and stuffing with rock wool/ceramic wool, or applying ceramic
rope (firebox window gasket material) as a spacer.
> I am making an annealing "oven" for nylon ...
>at ~ 350F, but the termperature will be a bit
> uneven, so places may get a good bit hotter.
> uneven, so places may get a good bit hotter.
> I will support the pipe from the side with a chemical ring stand setup.
>
> To minimize the heat lost through the suspension system, I need something
> that is a good thermal insulator to go between the 1/2" diameter metal
> support rods and the stove pipe.
Two standard ways of handling this, are fiberglass pads between the
>
> To minimize the heat lost through the suspension system, I need something
> that is a good thermal insulator to go between the 1/2" diameter metal
> support rods and the stove pipe.
pipe and clamp jaws, and use of tough but thin metal (brazed stainless
steel?) to make support brackets for the pipe.
Fiberglass is easily available (auto body repair stocks), and two inches of
thin metal should easily bridge from a hot pipe to a hold-in-your-hand
half inch rod.
You might also consider double-wall pipe, to control heat loss,
and stuffing with rock wool/ceramic wool, or applying ceramic
rope (firebox window gasket material) as a spacer.
Bob Engelhardt
Dec 8, 2012, 5:28:50 PM12/8/12
to
On 12/8/2012 9:20 AM, Bob Engelhardt wrote:
> ... use bolts. Given that
My main point here was "use bolts", but it should have been "you're
wasting most of the heat". With a heat gun, air is blown over heating
elements and onto/into the heat-ee. And then continues on its way! 90%
(95? 98?) of the heat is just going out the end of the pipe that you're
using as an oven. The minuscule amount that conducts down & out via the
supporting structure is irrelevant.
Bob
> ... use bolts. Given that
> you're using a heat gun and not heating elements, _most_ of the heat is
> going to be blown out the exhaust anyhow....
My main point here was "use bolts", but it should have been "you're
wasting most of the heat". With a heat gun, air is blown over heating
elements and onto/into the heat-ee. And then continues on its way! 90%
(95? 98?) of the heat is just going out the end of the pipe that you're
using as an oven. The minuscule amount that conducts down & out via the
supporting structure is irrelevant.
Bob
Doug White
Dec 8, 2012, 7:09:38 PM12/8/12
to
axolotl <munge...@shorecomp.com> wrote in news:k9vmc4$1i9$1@dont-
email.me:
> http://www.foamglas.us/building/products/product_overview/foamglas_slabs/
Interesting stuff, but absolutely no indication where to buy it...
Doug White
email.me:
> http://www.foamglas.us/building/products/product_overview/foamglas_slabs/
Interesting stuff, but absolutely no indication where to buy it...
Doug White
axolotl
Dec 8, 2012, 7:46:04 PM12/8/12
to
supply industrial boiler installations and manufacturing lines. Such as:
http://www.industrialinsulation.com/
Kevin Gallimore
Martin Eastburn
Dec 8, 2012, 11:22:34 PM12/8/12
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I found that you call the factory as it is specialized material.
If you can fit a 'standard' product - then the volume is needed...
Looks like they don't deal with you and me - but with builders needing
volume.
Many products are like that.
Martin
If you can fit a 'standard' product - then the volume is needed...
Looks like they don't deal with you and me - but with builders needing
volume.
Many products are like that.
Martin
Larry Jaques
Dec 9, 2012, 12:14:01 AM12/9/12
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On Sun, 09 Dec 2012 00:09:38 GMT, Doug White <gwh...@alum.mit.edu>
wrote:
330 pounds sterling for a cubic meter of foam? OUCH!
http://www.foamglas.co.uk/__/frontend/handler/document.php?id=841&type=42
--
...in order that a man may be happy, it is
necessary that he should not only be capable
of his work, but a good judge of his work.
-- John Ruskin
wrote:
http://www.foamglas.co.uk/__/frontend/handler/document.php?id=841&type=42
--
...in order that a man may be happy, it is
necessary that he should not only be capable
of his work, but a good judge of his work.
-- John Ruskin
Lloyd E. Sponenburgh
Dec 9, 2012, 8:10:04 AM12/9/12
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Doug White <gwh...@alum.mit.edu> fired this volley in
news:XnsA12369BA39390...@69.16.186.7:
> Rather than making a completely insulating threaded Teflon spacer, I
> may start with a 6-32 SS screw & a Teflon washer. I don't actually
> have true ring stand rings at this point, just rods & clamps. I was
> planning on just running a 1/2" rod out from a clamp, with a screw in
> the end through the stove pipe. The heat flow would be from the pipe
> to the end of the rod.
Doug,
Unless this has to withstand a lot of mechanical shock and weight,
How about making the parts from graphite?
It's got some mechanical strenght, good rigidity, and excellent
machinablilty.
Lloyd
news:XnsA12369BA39390...@69.16.186.7:
> Rather than making a completely insulating threaded Teflon spacer, I
> may start with a 6-32 SS screw & a Teflon washer. I don't actually
> have true ring stand rings at this point, just rods & clamps. I was
> planning on just running a 1/2" rod out from a clamp, with a screw in
> the end through the stove pipe. The heat flow would be from the pipe
> to the end of the rod.
Unless this has to withstand a lot of mechanical shock and weight,
How about making the parts from graphite?
It's got some mechanical strenght, good rigidity, and excellent
machinablilty.
Lloyd
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