teflon and continuous heat

[darryl]

Wondering how good is teflon in continuous contact with soft soldering heat? I need to make a holder for my heating element housing for the desoldering tool I'm building. I would use a ceramic, but I don't have anything suitably shaped. I do have a piece of teflon tubing that could make a couple of mounting pieces.

A simple test with a hot soldering pen seems to soften the teflon just a bit, but it doesn't make it burn or slowly form under pressure from the hot tip. My concern is that I won't be able to keep the heated housing solidly mounted to the handle with the teflon standoffs- I think it will loosen on me, and probably will never reach the point where it would remain solid.

I think I should look harder to find some ceramic bits that could be used instead. I had considered using stainless straps to go around the element housing, then mount to an aluminum handle- figuring that the handle would get quite warm after awhile, but would never get too hot to hold because of the relatively poor heat transfer ability of the stainless straps. I'm second guessing this as we speak-

I do have a section of thinwall stainless tubing in the works for the initial connection between the hot tip and the hose leading to the vacuum pump, and I'm going to rely on the aluminum handle to keep the lower end of this tubing cool enough to not affect the hose. The handle will still get warm, but it will act as a heat sink and dissipate most of the heat coming into it- but of course I need to minimize the heat conducted from the element housing into the handle.

[Jim Shaper]

What element are you trying to support?

My cheapy weller soldering pencils have a stamped stainless (or chromed) shield wrapped around the element that would be pretty easy to add a couple brackets to and isolate the heat via more stainless and a little distance.

[Circlip]

Nozzle and piston face on my solder sucker are made from teflon/PTFE and take on a very dog eared appearance from new after few operations.

Regards Ian

[darryl]

Maybe I'm over-engineering it. The element is 60 watts or so, and it's inserted into a stainless tube that's 2 inches long and 1/2 ID. The handle will be two pieces of aluminum sandwiched together, which could pinch a pair of strap clamps holding the element. I think maybe if I did a neat job of wrapping a bit of fiberglass cloth around the holder where the straps would go, then put more cloth over the straps where they pinch between the handle sides- possibly all will be well.

I could silver solder two studs to the element holder, then plant those studs in holes in the handle using furnace cement. That might give a low enough rate of heat transfer, and it would look and feel solid. A couple of round heat sinks attached to the studs would help, and would keep the element housing from touching the desk top If I laid it down. Might be a good idea, and it could look zoomy-

[PTSideshow]

Just so you are aware, In two to five minutes on a conventional stovetop, cookware coated with Teflon and other non-stick surfaces can exceed temperatures at which the coating breaks apart and emits toxic particles and gases linked to hundreds, perhaps thousands, of pet bird deaths and an unknown number of human illnesses each year, according to tests commissioned by Environmental Working Group

DuPont wrote that "significant decomposition of the coating will occur only when temperatures exceed about 660 degrees F (340 degrees C).

In cases of "Teflon toxicosis," as the bird poisonings are called, the lungs of exposed birds hemorrhage and fill with fluid, leading to suffocation. DuPont acknowledges that the fumes can also sicken people, a condition called "polymer fume fever."

Have no Idea if the same affect happens with solid stock Teflon. But as with all things it is something to consider when it will be in contact with constant heat.

You may want to check out the local ceramic supply for the small ceramic bits, called kiln furniture. You can cut it to size on the small tile saws.

[Black_Moons]

Use steel or ceramics, Given a masonary bit, drill press, weight on the feed handle, dam for coolant around the hole and about 1/2 hours time, you can drill through many ceramics or masonary if needed

Id personaly just use some kinda steel. or just buy the $15 springy holders they sell with the little sponge holder (Do you have something to clean your iron tip like a sponge or the brasso pad looking things? they are EXCEPTIONALY important, especialy for SMT)

Yea it will heat up, but thats why you don't touch it where it holds the iron.
Being a 60W iron you don't have to worry about excessiveing 'cooling' it really, but it would be somewhat in your intrest to make your design not a heatsink. (ie the long curly wire design prevents heat from being conducted down into the base)

http://www.conestogac.on.ca/~rsibley...llerEC3000.jpg

Something like that.. I believe the neck is made outta bakolite or something. It gets small burn cracks and such marks in it over time but seems to hold togethor.

Other options include some kinda handle clasp: http://www.mobilephone-spares.com/pr...ion-936%2B.jpg

Note that some cheaper irons the handle can get to 60c+ so I would'nt exactly use any of the softer plastics for it like PVC/acrylic

[portlandRon]

Look this over before you use teflon http://tuberose.com/Teflon.html

[Evan]

You gotta engage the critical thinking muscle before you read this stuff.

In two to five minutes on a conventional stovetop, cookware coated with Teflon and other non-stick surfaces can exceed temperatures at which the coating breaks apart and emits toxic particles and gases linked to hundreds, perhaps thousands, of pet bird deaths and an unknown number of human illnesses each year,

If it causes an unknown number of human illnesses each year how do they know it cause any at all?

Teflon doesn't begin to decompose to toxic gasses until around 800 degrees F. It is exquisitely toxic to birds in that instance at levels that a human would never notice.

However, so is burnt butter in a teflon frying pan.

Birds are extremely sensitive creatures and keeping your bird's environment free of potentially deadly fumes is part of providing a safe home for your pet. Even the slightest exposure to certain airborne chemicals can be devastating. Birds are sensitive to carbon monoxide as well as airborne particles of insecticide sprays, hair spray, perfumes, paint fumes, room deodorizers and even bleach or ammonia fumes.

Birds are also sensitive to smoke, and cigarette, cigar and pipe smoke can be quite damaging. Burnt oil or butter or even smoke from a fire can also cause severe breathing trouble. The fumes from burnt pans with non-stick coating and fumes from self-cleaning ovens contain the toxic chemical polytetrafluoroethylene (PTFE). Any item with a non-stick coating should not be used around birds, even if it is not overheated.

http://www.petplace.com/birds/birds-...mes/page1.aspx

[bob_s]

Teflon melting point = 327*C (651*F)
Reduction in physical properties = 260*C (500*F)

Soft solder (non-lead) melting point = 381*C (718*F)

=Teflon ain't a good idea

Made soldering iron holder out of an old tube socket, of course if you are too young to know what an electron tube is .... moot

[Scishopguy]

An old ceramic ashtray works well for pencil type soldering irons. I have a round one with two notches for butts that let the iron rest easily in a cradle. Glass ash trays are almost free at any flea market. I'd nix the teflon idea and go with cheap and available.