Inverter Tig Welders

I need to weld some thin mild steel and find that my Mig is a bit crude and vicious on mild steel this thin. I'm wondering if one of the
modern DC Tig inverter welders would be better for thin mild steel. Of course a full AC/DC Tig would be nice for versatility but they never come anywhere near a sensible price.
Any direct experience of the current crop of DC Tig inverter welding kit welcomed.
Thanks
Charles
http://www.homeworkshop.org.uk
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Charles Ping wrote:

Charles
No *direct* experience, but as no-one else has answered....
I've got what you might call a 'first generation' cheap & cheerful inverter TIG set, it works, the HF (which is spark generated) seems to me too powerful when working at low currents as it can tend to swamp the welding current. Having said that, I've never really mastered TIG anyway.. It serves an excellent stick set, btw. Nowhere near as light & portable as some of the current offerings.
Not TIG, just a basic stick set, I recently bought an R 140i from
http://www.newarc.co.uk /
which is a brilliant little set, with the emphasis on little. If you could run to one of their TIG sets, I doubt that you would be disappointed.
im
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I've got a Cebora DC set-up, but it's not exactly at the cheap end of the scale, but certainly no where near the expensive end. I picked mine up of ebay a couple years ago for a good price. I think I paid about a 1/3 retail for a machine in as new condition.
It's mainly been used for repairing rusty body panels, but occasionally sees use on stainless. Personally I'd recommend paying more for HF start, as it makes starting welds far easier. I have used the lift start option, and although it's perfectly useable (might mainly be due to the cebora electronics which ramp up the current after you lift off), HF is just so much easier.
Plus as Tim has said, it doubles up as a very nice stick welder (although remember to swap the neg/pos leads around, otherwise it can make for some interesting welding attempts!)
moray
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 21 Jul 2008 07:37:24 -0700 (PDT), Charles Ping

For really thin stuff, TIG with a pedal and/or pulse mode would give the desired control. But they're expensive. Also, AFAIK TIG needs argon or argon mixes, which are expensive.
--
-Pip

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Do you have to weld this? Brazing may be a better alternative as it doesn't melt the parent metal. Have you considered gas welding? When I needed to weld some thin steel, I found a gas set beat a MIG welder. My technique was to use a thick filler rod as a thermal mass to avoid making holes in the steel. Preheating the end of the rod to almost meting point before applying it to the weld area helped as well.
John
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thin steel with compound curves - and there's a lot of it to patch up so silver soldering or brazing would be very expensive (even if I could keep the heat distortion at bay). Gas in my book has two big problems. The distortion is one and the cost of the bottles is another. If I tot up what I've paid BOC in rental over the past decade for just one argon bottle it'll be a lot more than the cost of a TIG welder. The fact that I have MIG already does mean that MIG and TIG can share gas and it becomes a sensible option.
Charles
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 28 Jul 2008 04:13:27 -0700 (PDT), Charles Ping

Charles
Do you use straight Argon on your MIG? I suppose it would be OK on thin material, I tried it on 4mm plate a few years ago when I ran out of mixed gas, panic job on a Sunday, I did struggle do get a decent result.
Tim
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I would have thought 4mm was a bit much even for mixed gas. pure argon would probably be dire at that thickness.
Pub gas in bought bottles is far more economic than BOC's extortion for MIG :-|
Mark Rand RTFM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 28 Jul 2008 22:23:58 +0100, Mark Rand

There are different mixtures for different thicknesses, BOC offer Argon with 5% CO2 for thin stuff up to 4mm, 12% for 4 to 10mm & 20% for 10mm & upwards, with a sniff of O2 for good measure.
Tim
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Conviently sold as Argoshield Light, Universal, and Heavy. The O2 trace helps burn impurities out of MIG welds, but it means it's useless for TIG welding, so you have to pay about twice as much for an equivalent sized bottle of pure argon.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.