I've thought about doing this as well, as my 25W for CBs just doen't cut it
for taking care of my auto needs, although I have been using it.  Only one
thing you forgot to mention: What iron are you using with your rheostat?
Did you get a new one or are you just using your 40?

I'm trying to think of a project I saw once that allowed you to see how
much juice you were giving your appliance but I have no idea where it is,
nor the time to figure it out for myself (it had a nice digital display...)

Just curious...

J89

>I have lusted after the Weller variable temp irons for a while now
>but couldn't justify the cost for my limited tinkering and repair.  I
>have 2 irons, a 25W one I use for circuit boards and a 40W one that
>works nice for automotive wire.
>
>The problem is the 40W model just plain gets too hot and scorches my
>flux and degrades the tinning solder.  So, using some cross-platform
>technology from bee-keeping, i now have a variable temp iron.
>
>In bee-keeping, we use a 'hot knife' for removing the wax cappings
>from the frames of honey.  Same problem as the soldering irons-- the
>hot knife gets too hot sorching the wax and honey, even tho it has a
>crude on/off regulating thermostat.  I built a 110V rheostat that
>allows me to regulate temps or speeds on a variety of devices.
>Essentially, it is a rotary lamp dimmer wired to a 110V receptacle
>and placed on a line cord.  Plug the device into the outlet, set the
>dimmer to whatever output you need and the rest is Duck Soup.
>
>Here's what you need:
>-metal 2-gang junction box.  ~$2
>-600W dimmer.  $8
>-110V outlet.  $0.69
>-dual cover plate that has and opening for the 110v outlet and a wall
>switch. $1.
>-3M rubber feet. $2
>-old 3 wire extension cord.
>-metal line cord clamp for junction boxes.
>-a few wire nuts.
>
>Wire the dimmer to control the 110v outlet.   cut off the female end
>of the old extension cord and wire this to the dimmer. mount all
>this in the junction box.   as the old saying goes, if you need more
>detail than this you shouldn't be trying it.  add the cover plate to
>the box and put rubber feet on the bottom of it.  now all i do is
>plug in this rheostat box to an outlet, plug my solder iron or hot
>knife into the controlled 110v receptacle, and crank to the best temp.
>
>This allows me to have my iron on for extended periods without it
>turning to a black crust, yet have enough heat to really do a nice
>job.
>
>-dan

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