Looking to TIG weld fine mesh to stainless frame.

[steve.hall30]

I'm looking to weld some stainless steel (304L) woven wire mesh, like this stuff (http://www.inoxia.co.uk/rw/category/9.aspx to a stainless steel frame.
The wire mesh ranges from 0.9mm (20SWG) wires spaced every 6mm, to 30μm (49 SWG) wires spaced 400 per inch, and everything in between. The frame is likely to be something like 3mm flat bar, or 1.5mm walled box section (30mm box).
So, questions:
1) I'm sure the 0.9mm wires will weld to the bar or box with no trouble, but how fine could I really get away with, surely you can't weld a woven mat of 0.03mm thick wires?

2) What sort of technique and set up should I use on the welder? I don't own the machine yet, but thinking this one should have the right selection of dials to get something to work. http://www.r-techwelding.co.uk/welding_equipment/Tig_Welder/Tig_Welder_R-Tech_Tig200PDC

I did manage to work out today from research, that a laser welder would be ideal, and that they cost a pretty penny, so looks like TIG is the only affordable choice.

I will really appreaciate any advice on this tricky weld.

 

[Shox Dr]

Tricky it will be, I've welded a lot of .9mm perforated sheet and that's not fun to begin with.

I would start the arc off on a 1.6mm rod and move it the mesh, you want 20/30amps 1.6mm tungsten with a very sharp point, I would also play with some bits, as you will burn a lot of mesh before you get the hang of it. I would also go with the 1.5 box as 3mm will be no fun at all

 

[Slim Shady]

With TIG you can weld anything, I worked with a welder who could weld the tin foil on his cheese and ham sandwiches without melting the cheese. I prefer using a standard inverter welder with no pulse or any tig controls. Lift Tig. You wont need any filler, turn it down to 10 amps, the smallest tungsten you can find and turn the gas to about 5lpm for the mesh.
For the welder I personally would go for THIS and THIS to make it a TIG. I am slightly against R-Tech because I bought a DC tig 5 minutes of welding DEAD, sent it back, got a new one 10mins welding DEAD. in the end I just got a refund
If you do need any help with it just PM me.

Sorry for the long post
OutCastReddyBoy

 

[gavuk]

i'm sure it can be done with tig ,but i did some mesh at work with a gas torch and silver solder was much quicker and easier than tigging ,as for filler rods there are much more knowledgeable people than me on here ,i do know the rods weren't cheap.It may be an alternative to consider ?...

 

[Slim Shady]

oh rods i forgot,
get a number equal or higher than the grade of stainless you are welding.
weldequip has good value, so does rapidwelding
silver solder is WAY too expensive.

 

[RapidResponse]

I did some work with this kind of mesh to some fairly heavy steel and we used mig brazing. Cu si3. Tig brazing also works but was too slow for the amount we did.

 

[Shox Dr]

Didn't think of brazing it, would be a lot easier than trying to weld it to 3mm, been so fine.


There's a guy on you know where that sells small amount of Tig brazing rod

 

[Master-of-none]

To deal with the finer mesh, consider crimping on a border strip or use adhesives.
these sieves use a 'proprietary polymeric adhesive' to secure wire mesh to a frame.

 

[steve.hall30]

Thanks for the ideas.
A bit more info, I'll have to complete about 30m of welding/brazing/soldering per job if I want to replace the current clamping method. How long would this likely take with tig vs brazing vs solder?

I know of the acid core silver soldering technique, which is used on small mesh to mesh joins. But 1) Will it join mesh to plate ok?, 2) Would a 30m silver solder joint be too expensive, can't actually find a propper UK supplier at the moment.

With brazing, what are the corrosion resisances of the stainless brazing rods like? The filters will be used in a tough environment, I can not have the joints fail. 304 minimum quality.

 

[Slim Shady]

sliver solder is very expensive depending on the silver content, it will hold no problem.
go to a refrigeration wholesaler for the rods