bending iron rheostat

[raybomando]

anyone know the brand or part # for an ibex/sloane style bending iron rheostat, i see the heating element for sale but can't find any information on the rheostat, thanks

[HoGo]

Check evilbay fo temperature controller or thermostat, rheostat is different thing.
make sure the voltage/ wattage/ temperature range is correct for your use...

[Dave Cohen]

In fact, the StewMac bending iron and other similar devices DO use an AC rheostat. The OP's use of the term is correct. The AC rheostat is a variable resister/potentiometer which varies the current through the device, thus approximately regulating the temperature of the aluminum housing. I haven't checked on a while, but I suspect that an online search for "AC rheostat" would locate an appropriate rheostat available for sale.

[Dave Cohen]

.....But you do have to find one with the highest wattage rating available. My recollection is that for a bending iron, it would need to be in the 1500-4000 watt range.

[Dave Cohen]

Had to check myself on the wattage, and of course, I was wrong. StewMac's info says their bending iron has a 200W rating.

[HoGo]

In fact, the StewMac bending iron and other similar devices DO use an AC rheostat. The OP's use of the term is correct. The AC rheostat is a variable resister/potentiometer which varies the current through the device, thus approximately regulating the temperature of the aluminum housing..

I thought rheostat is quite outdated these days... I made my bending iron twenty years ago with old giant rheostat originating from russian army radar and always thougt it was very odd solution as the rheostat produces almost half as much heat as the iron :-) certainly it is not very economical and I had to find out how to get rid of the redudndant heat and not burn myself :-) see pic.
I always thought these commercial products use better control methods than that. Every clothes iron has simple thermostat that cuts the current once desired temperature is reached.
Luthier bench's iron specifies thermostatic control as well. Are you sure S-M uses rheostat? I see that dictum has iron that looks exactly same as S-M minus threaded hole for extension and they mention thermostat control as well... here:
https://www.dictum.com/en/bending-ir...ng-iron-703920
BTW, is OP looking for a replacement part or is he building his own? Replacement part should be easily obtainable from StewMac. Just drop them an email.
200W looks pretty lame compared to my 2000W heating element. Mine is up to temp in 5-10 minutes and have to reduce the current by the rheostat to keep it from burning the wood.

[Richard500]

None of the above. Small (200W is small) heating elements are usually run from a basic SCR control, or lamp dimmer. The usual household version is good to at least 600W. I don’t know if you are looking for closed-loop, that is, thermostatic control, which can be several other configurations involving a sensing element like a thermocouple, and a power relay to cycle the power. That’s the better arrangement, but maybe not needed for this application.
A 200W rheostat, that is, variable resistor, is a large (and hot) device. Alternatively, a variable transformer (generic: Variac) good for a few amps will also give good control, but these are fairly expensive these days. It won’t waste much power, and works better with inductive loads, like motors. Lamp dimmers don’t.
A clue, if you have the heating element is how many leads it has: two=just heat, four=heating coil and temp sensor.

[CarlM]

I thought rheostat is quite outdated these days... I made my bending iron twenty years ago with old giant rheostat originating from russian army radar and always thought it was very odd solution as the rheostat produces almost half as much heat as the iron :-) certainly it is not very economical and I had to find out how to get rid of the redundant heat and not burn myself :-) see pic.

Well that makes it fairly straightforward. Just find a Russian army radar to cannibalize.

[raybomando]

problem solved, went to an old school appliance parts store and he hooked me up, differant brand but same rating and connections. the problem lies in being 120v, it is in fact a rheostat. i have a sloane/ibex i purchased from international violin around 1999, i also bought a new element from lmi and changed all the wire connectors, all is good. i'm 70 nw, hope it last a couple more years. ha ha

[HoGo]

problem solved, went to an old school appliance parts store and he hooked me up, differant brand but same rating and connections. the problem lies in being 120v, it is in fact a rheostat. i have a sloane/ibex i purchased from international violin around 1999, i also bought a new element from lmi and changed all the wire connectors, all is good. i'm 70 nw, hope it last a couple more years. ha ha

Can you post a photo/ description of the item for future reference? Thanks.

Those old school part srores are rare these days even here where folks often repair their own applianced themselves.
I bought my heating element in such store (sadly doesn't exist anymore), but the rheostat was from junk left by the russian army when they moved back home in 1990 from our country. I remember I needed to make me a bending iron (buing one was nearly impossible here back in early 90's) so I went to the store and asked for heating element that would stand dry heating and fit into steel pipe. I welded the pipe and mounted it on piece of wood but needed some way of regulation and mentioned it to my father (he was an army officer). Next day he appeared with big box saying he asked some technicians at work and they had this old rheostat laying around :-)
Luckily the rheostat matched the power and work just perfectly, keeps the temp where needed when it is turned just half way but produces helluva lot of heat. You can cook eggs on the steel cover :-)
I wonder how th S-M iron deals with the rheostat heat inside the wooden base? I was thinking few months ago about building me a mandolin side bender using custom made shaped heating elements and digital controller, perhaps in the near future...

[Richard500]

Gosh, suppose I have to show pix. In the photo below, from left to right, A 100W rheostat, i.e. a variable resistor, a cartridge heater for a few hundred watts, a thermostatic switch, a wall mounted lamp dimmer, 600W. I also looked at the S-M device, and it almost certainly is a lamp dimmer and a 200W heater, which is a bit slow for this particular job: it is also not thermostatic, that is, like an electric stove element, so you need an accurate surface themometer, also vastly overpriced and the temperature is unregulated in the sense that using it on wet wood lowers the temperature. A silly device.
To be charitable, a guy in an appliance store, or even a few licensed electricians don’t know what a rheostat is, or how a dimmer actually works.
The other picture is a recent, low cost digital 600F thermostat, including a power relay and adjustable setpoint. It’s on my woodstove. This, plus a higher wattage heater, say 1kW (like a clothes iron) would make a fast heating, thermally settable, stable bending jig, if anyone cared.
The outlet is just to show sizes. A 200W rheostat is indeed quite large, and needs ventilation.