generic 230 v heating coil element ?
 

Am trying to restore and antique theater popcorn popper that has a
burned out heater. This is a 230 volt element and I wonder if anyone
has found any place that sells just the coil element that I could use as
replacement. Was thinking of a clothes dryer element also. thanks.
Dale

Not sure what the shape is supposed to be but I would check out Johnstone
supply they carry electric range elements as well as dryer ones. They have
pictures of them so hopefully you can find one that matches the shape you
need!

http://www.e-johnstonesupply.com/scr...yes&category=1


Wayne


"dale" wrote in message
...
Am trying to restore and antique theater popcorn popper that has a burned
out heater. This is a 230 volt element and I wonder if anyone has found
any place that sells just the coil element that I could use as
replacement. Was thinking of a clothes dryer element also. thanks.
Dale

According to dale :
Am trying to restore and antique theater popcorn popper that has a
burned out heater. This is a 230 volt element and I wonder if anyone
has found any place that sells just the coil element that I could use as
replacement. Was thinking of a clothes dryer element also. thanks.

Conceptually, it's not too hard to get it operational again, but given
you call it an "antique", and "antique" implies that it could be
_VERY_ old and unsafe (ie: no thermal cutouts etc), I'd be very
nervous about it. Be sure to have a safety kill switch and
a fire extinguisher handy...

If the existing element has one or two breaks, you can often get
them brazed or silver-soldered to give it a few more years of life.

Alternately, if you can determine the wattage and dimensions of the existing
coil element, you may be able to find a clothes dryer element that has
the right wattage, roughly the same coil length and diameter, and cut
it out of the element frame (if the frame can't be reworked to fit) to
get to the raw coil and restring it.

It's also possible to make your own heating elements from raw nichrome,
but that will require considerable care in ensuring you get the final
temperature right. A really good appliance service center might
be able to do that.

If you can't braze the existing element, I'd take the unit into
a good appliance service center and ask if they can match the
voltage, wattage, and length parameters.

How many watts is this thing anyway? Dryer elements are in the
4500-6000W range - that seems a trifle high even for an industrial-duty
popcorn maker.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.

Thanks for the tips. I found out that the company no longer has parts
for this so I will have to improvise. I can braze and silver solder but
I think braze would be better as it would stand more heat. Don't know
even then if it gets red hot as they do on old hot plates that it may
melt brazing. I was thinking of just bolting it together at the break.
Worth a try I guess. Cant find the wattage but I may look on the
newer models. Thanks Dale

Chris Lewis wrote:

According to dale :

Am trying to restore and antique theater popcorn popper that has a
burned out heater. This is a 230 volt element and I wonder if anyone
has found any place that sells just the coil element that I could use as
replacement. Was thinking of a clothes dryer element also. thanks.


Conceptually, it's not too hard to get it operational again, but given
you call it an "antique", and "antique" implies that it could be
_VERY_ old and unsafe (ie: no thermal cutouts etc), I'd be very
nervous about it. Be sure to have a safety kill switch and
a fire extinguisher handy...

If the existing element has one or two breaks, you can often get
them brazed or silver-soldered to give it a few more years of life.

Alternately, if you can determine the wattage and dimensions of the existing
coil element, you may be able to find a clothes dryer element that has
the right wattage, roughly the same coil length and diameter, and cut
it out of the element frame (if the frame can't be reworked to fit) to
get to the raw coil and restring it.

It's also possible to make your own heating elements from raw nichrome,
but that will require considerable care in ensuring you get the final
temperature right. A really good appliance service center might
be able to do that.

If you can't braze the existing element, I'd take the unit into
a good appliance service center and ask if they can match the
voltage, wattage, and length parameters.

How many watts is this thing anyway? Dryer elements are in the
4500-6000W range - that seems a trifle high even for an industrial-duty
popcorn maker.

"dale" wrote in message
...
Thanks for the tips. I found out that the company no longer has parts
for this so I will have to improvise. I can braze and silver solder but
I think braze would be better as it would stand more heat. Don't know
even then if it gets red hot as they do on old hot plates that it may
melt brazing. I was thinking of just bolting it together at the break.
Worth a try I guess. Cant find the wattage but I may look on the
newer models. Thanks Dale


If you need to know the wattage measure the two pieces of old element with
an ohm meter and then do the math.

A handy calculator :

http://www.minco.com/support/ohm.php

A section of replacement element for a clothes dryer might work well........

--

SVL

Thanks for Ohms law calculator THat is neat for a guy who can not
remember it. Dale

PrecisionMachinisT wrote:
"dale" wrote in message
...

Thanks for the tips. I found out that the company no longer has parts
for this so I will have to improvise. I can braze and silver solder but
I think braze would be better as it would stand more heat. Don't know
even then if it gets red hot as they do on old hot plates that it may
melt brazing. I was thinking of just bolting it together at the break.
Worth a try I guess. Cant find the wattage but I may look on the
newer models. Thanks Dale



If you need to know the wattage measure the two pieces of old element with
an ohm meter and then do the math.

A handy calculator :

http://www.minco.com/support/ohm.php

A section of replacement element for a clothes dryer might work well........

According to PrecisionMachinisT :

"dale" wrote in message
...
Thanks for the tips. I found out that the company no longer has parts
for this so I will have to improvise. I can braze and silver solder but
I think braze would be better as it would stand more heat. Don't know
even then if it gets red hot as they do on old hot plates that it may
melt brazing. I was thinking of just bolting it together at the break.
Worth a try I guess. Cant find the wattage but I may look on the
newer models. Thanks Dale

If you need to know the wattage measure the two pieces of old element with
an ohm meter and then do the math.

A handy calculator :

http://www.minco.com/support/ohm.php

A section of replacement element for a clothes dryer might work well........

Ah, to a certain extent, yes. But if you try to shorten the length dramatically
while keeping the same voltage, you'll probably burn out the element. Even
with active and tightly coupled thermostatic control (an "antique" may not have
such a thermal cutout let alone thermostatic control) the lifetime will probably
be dramatically shortened.

Heater wire has a positive temperature-resistance coefficient. Which means,
as the temperature goes up, the resistance does too, _tending_ to self-regulate
power consumption and keep the temperature constant even with reasonably
minor voltage variation. Which means that the cold resistance is often very much
different than operating resistance, and depending on the composition of the heater
wire, the old coil might have the same resistance as the new coil when cold, but have
radically different resistance at operating temperatures.

[Tungsten lightbulb filaments do the same thing, but not as dramatically as
traditional nichrome heater wire.]

The best way to measure operating resistance (assuming nowhere on the device is
a plate saying what the wattage is) is to somehow get the breaks fixed
temporarily, fire it up, measure operating current, and do the resistance
calculation _then_. But keep in mind that's the hot resistance, not cold.

Reducing the length of a dryer element is presuming that the dryer wattage is
_lower_ than the corn popper (unlikely). Halving the length of the dryer
element doubles the wattage and quadruples the heat output per inch (assuming
constant resistance, which it really isn't, but...). Given how they engineer these
things with relatively close design tolerances (higher wire guage costs money),
I'd expect the lifetime to be shortened no matter how good (the likely non-existant)
thermostatic control is.

So, the most convenient yet reasonably inexpensive method of replacement would
be to find a dryer element that roughly matches in length and wattage.

If it turns out that the OP can only find a dryer element with double the wattage
and roughly double the length, he could cut it in half and rewire the
corn popper for 120V.

He could probably obtain the nichrome wire himself and wind his own
heater coil easily enough. I'm _sure_ there's web sites that show you
how to design heater coils using nichrome wire, ie: how to select wire
gauge for given desired lengths, wattages and supply voltages. But
I haven't looked for any such sites.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.

"Chris Lewis" wrote in message
...
According to PrecisionMachinisT :

"dale" wrote in message
...
Thanks for the tips. I found out that the company no longer has parts
for this so I will have to improvise. I can braze and silver solder
but
I think braze would be better as it would stand more heat. Don't know
even then if it gets red hot as they do on old hot plates that it may
melt brazing. I was thinking of just bolting it together at the
break.
Worth a try I guess. Cant find the wattage but I may look on the
newer models. Thanks Dale

If you need to know the wattage measure the two pieces of old element
with
an ohm meter and then do the math.

A handy calculator :

http://www.minco.com/support/ohm.php

A section of replacement element for a clothes dryer might work
well........

Ah, to a certain extent, yes. But if you try to shorten the length
dramatically
while keeping the same voltage, you'll probably burn out the element.
Even
with active and tightly coupled thermostatic control (an "antique" may not
have
such a thermal cutout let alone thermostatic control) the lifetime will
probably
be dramatically shortened.

Heater wire has a positive temperature-resistance coefficient. Which
means,
as the temperature goes up, the resistance does too, _tending_ to
self-regulate
power consumption and keep the temperature constant even with reasonably
minor voltage variation. Which means that the cold resistance is often
very much
different than operating resistance, and depending on the composition of
the heater
wire, the old coil might have the same resistance as the new coil when
cold, but have
radically different resistance at operating temperatures.

[Tungsten lightbulb filaments do the same thing, but not as dramatically
as
traditional nichrome heater wire.]

The best way to measure operating resistance (assuming nowhere on the
device is
a plate saying what the wattage is) is to somehow get the breaks fixed
temporarily, fire it up, measure operating current, and do the resistance
calculation _then_. But keep in mind that's the hot resistance, not cold.

Reducing the length of a dryer element is presuming that the dryer wattage
is
_lower_ than the corn popper (unlikely). Halving the length of the dryer
element doubles the wattage and quadruples the heat output per inch
(assuming
constant resistance, which it really isn't, but...). Given how they
engineer these
things with relatively close design tolerances (higher wire guage costs
money),
I'd expect the lifetime to be shortened no matter how good (the likely
non-existant)
thermostatic control is.

So, the most convenient yet reasonably inexpensive method of replacement
would
be to find a dryer element that roughly matches in length and wattage.

If it turns out that the OP can only find a dryer element with double the
wattage
and roughly double the length, he could cut it in half and rewire the
corn popper for 120V.

He could probably obtain the nichrome wire himself and wind his own
heater coil easily enough. I'm _sure_ there's web sites that show you
how to design heater coils using nichrome wire, ie: how to select wire
gauge for given desired lengths, wattages and supply voltages. But
I haven't looked for any such sites.

Chris,

Nice post.

--

SVL