From: Sam Nichols
Subject: Re: Help creating a heating element from resistor.
Date: Mon, 09 Dec 2002 09:48:53 -0800
User-Agent: MT-NewsWatcher/3.2 (PPC Mac OS X)
In article ,
> Sam wrote:
> > In article ,
> > "George R. Gonzalez" wrote:
> >> "Sam" wrote in message
> >> news:sizam-6B65B5.firstname.lastname@example.org...
> >> > Hello,
> >> > I'd like to create a small heating element running on as low a
> >> > voltage/current as possible and heats up to about 250 deg C. I'd like
> >> > to pump a fluid over it and have that fluid vaporize.
> >> We need a bit more info. How much fluid do you want to vaporize
> >> per unit time? What's the heat capacity of the fluid? What is its
> >> boiling point temperature? What is its heat of vaporization?
> >> Witht hat info we can calculate how many watts is required.
> > I'm not quite sure what the flow rate will be yet, pretty low, I'll be
> > using as small a pump as possible. Everything togeather should weigh
> > 3oz or less and another 2oz of liquid, the 3oz includes a battery to run
> > this on. The fluid is oil, don't konw what the heat capacity is, flash
> > point is 240 deg F, API gravity is 38.3. I was looking at a site that
> > carries Nichrome wire and they had some tables to help figure out what
> > you need (http://www.wiretron.com/nicrdat.html). It looks like if I
> > used AWG 40 wire I could get by with only needing to generate about 8
> > watts which I could get from 2 1.2V batteries at 3 amps. Is Nichrome
> > more efficient at generating heat from electricity then a resistor?
> Why do you want to evaporate oil?
> Off-hand, I'd say it's not going to happen, as the battery would be
> too heavy.
Sure it could happen, I have 1000 mAh NiMhs that weigh 0.75 oz each,
which leaves 1.5 oz for a pump which will be mostly plastic and a tiny
motor, and some Nichrome wire which seems like it'll weigh close to
nothing. I guess it might be closer to 4 oz which could still work. I
want to vaporize oil for a tiny smoke machine.
Anybody know a place that carries Nichrome in the Bay Area?