Sacrificial Embedded Heating Element

Hi TC,

What is the scale of the mesh - aperture size. House screen or chicken wire or somewhere between?

Also, are you laminating single sheets or is this a web process?

The heat that you can get from the mesh will depend on the voltage supplied and the resistivity of the mesh.

Mike

size will vary from 2' x 2' to 12' x 12' and variations there of.

I am thinking a very thin wire with as large a weave as possible (3/16"?) to allow surface heating of the entire area and penetration of the melt to adhere to the textile.

I'll have to do some research, but things are getting busy and I'll have to wait until I get home.

I'll catch up with you later.

Mike

With the right controls any wire can be heated to temp. A 12' by 12' wire mesh it maybe hard get every strand to conduct evenly. Couldn't you use a rollers. Rolling the three together thru infrared oven to laminate them.

the idea at present is to have a standard width mesh roll - say 3' roll - with current control to each segment. A 12' product would have 4 rolls/segments with independent controls. The length would be variable.

It would be nice to think that all the strands in the wire mesh are the same. If they are not you will face hot spots. The machine weaving it can scratch the wire, bend and deform it. Is the wire mesh to preform the function of heating in the product?

yes. i need as fine a filament is practical. dunno .007" or so. depends on the weave too. I want something very loose and pliable. fishnet in consistency.

the mesh will be embedded permanently but there should be no trace of it whatsoever. It should be light enough to just heat effect the top 33% of a .09 - .125" thick sheet of plastic.

if I have to have something custom woven that is not a problem. obviously would rather go off the shelf. $$$

TexasCharley I have many years of experience working with industrial hot melt adhesive, working temps from 150 to 170 degrees centigrade. We melted the adhesives in aluminum tanks outfitted with heaters and thermalcouples to control and maintain the optimum temperatures, a few degrees to high and you char the hot melt. My experience showed that if you were to pour this on to cloth it would not wet the material as much as it would just lay on top and adhere to the fibers standing up. You may have to do as suggested and run the cloth and hot melt between rollers to force the penetration of the cloth. We used nozzels to apply the adhesive and a few degrees to low it wouldn't penetrate and a few degrees to hot it would pass all the way through so controlling temperatures was critical to application. This is just some background and if you give more details of what your trying to achieve I might be able to supply additional info. Good luck, J.Conway

sending PM.

yes we will be using rollers. material is fibrous - like jute.

TexasCharley As strange as it sounds this product can be sprayed on. There are companies that manufacture systems to spray hot melt with nozzels that atomize and apply at variable rates. J.Conway

Take my word for it: when working around hot sticky stuff, make sure to keep your hairy, little body covered up.

TC,

Try a welder. They are used to heat frozen pipes. Connect one lead to each end of the mesh. You will have to experiment a little to see what amp setting gives you the desired temperature

Hope you don't mind tangential thinking

Ever thought of using a fine Cu alloy or steel wire and heting it by high frequency eddy current ? like induction heating/ Induction hardening process ?

This way you can go ahead with uniform heating of the surface withou bothering about other aspects.

Only problem as I see is you will not have sacrificial heating element you will have sacrificial heated element

Thanks all so far. And, no SB, I do not mind tangential thinking. Hell this whole thread is an exercise in tangential thinking.

I have a bit of tinkering to do - It involves a hot glue gun a soldering iron a meat thermometer some aluminum screen material and an estimated 8 cups of strong coffee.

Am convinced we can get the details worked out. One of the things I really enjoy about this forum; no-one comes out saying " oh no that will not work" around here and I can consider that point as a Green Light.

Now its just workin' it out. will keep you posted on results.

Why do you need to heat up the embedded wire mesh? Could you not grind your binding agent (glue, plastic, powder coat paint, whatever) into dust, sprinkle it on evenly, and then pass the whole assembly under a radiant heater? I envision a hopper arrangement full of cold powder sitting about a 32nd of an inch above the surface of your fabric. The fabric would be moving, being pulled under the hopper, and then under a radiant heater. Alternatively I suppose, you could have the hopper and heater moving and the material remain stationary, but then you would need to really good non-stick surface underneath.

To all who are suggesting the traditional radiant heat approach. I am aware of this technology. But I do not have the luxury of the cost of said equipment and I need to control the temp in a more localized manner.

Thanks.

Am wiring in some outdoor lighting at Mom's today. Should be in my garage tomorrow for inital build/protoyping of mesh system.

Be aware that this already exists.

Raychem had a heat shrink boot with electro thermal activation: a wire in the polymer heated the complete unit, melting the glue.

while shrinking the glue fills up all voids and seals.

They had it with two techniques: wire in the polymer and a conductive polymer which heats up by the passing current.

Several tube suppliers still have the wire in polymer system in their product bag for easy field adaptations of PE piping.

This is wonderful news. I will see if I can find more info. I am not looking to patent anything necessarily. Just need to improve my process.

Thanks Gwen.

Where ya' been?

TexasCharley Another item to add to your arsenal is hot air, a hand held hot air gun will rapidly melt this material. I don't know if you could expand on this method but this is how we cleaned the melting tanks and accessories. J.Conway

My only question is "who are you sacrificing to?"