TIG experts, inside please.
10-15-2005, 11:48 AM
#21
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[QUOTE=Brains] I also need to get my motion a little better, I'm currently more or less moving in a steady forward direction and only pausing slightly to add filler. From what I've read, it says the proper motion is to back up, dip the rod, and then move back over the puddle again?
QUOTE]
a little motion with the torch is fine, but you don't have to do it the way you read about......with a butt weld like what you are doing, i would just keep the torch moving steady and straight, and get a nice "rod dipping" rythm going.....i don't weld very much pipe like that , but when i do i usually only weld in inch or so increments before i adjust myself, it's easier for me to keep the torch angle relatively consistent....
QUOTE]
a little motion with the torch is fine, but you don't have to do it the way you read about......with a butt weld like what you are doing, i would just keep the torch moving steady and straight, and get a nice "rod dipping" rythm going.....i don't weld very much pipe like that , but when i do i usually only weld in inch or so increments before i adjust myself, it's easier for me to keep the torch angle relatively consistent....
10-15-2005, 04:11 PM
#22
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Just a couple of suggestions-
-Clean the zinc or whatever is on that metal befor you weld it and it will turn out a lot better. It isn't real good for your health to breath those fumes and it is real easy to contaminate the tungsten with it. Try and remove on both sides of the metal if it is coated.
-Get a very bright light and iluminate the weld . You'll be amazed at how much difference it makes. A reflective lens will help too. I have a pair of glasses with a focal length ideal for welding. Friends of mine use 'cheaters' to good effect. Try different lens density and see if there is one you like better
-get a 'gas lens' for your TIG torch
- Your fit-ups should be line to line. That sometimes makes the joint hard to see, so I'll sometimes put a indelible pen mark about 3/16 from the joint as a guideline to keep the weld straight.
-Tack the tube in three places before you start welding. I try to weld between the tacks continuously.
-Use more filler, or
- Holley or Hooker make a 'welding ring' that you can buy for cheap that is basically a sleeve with an upset in the middle that is consumed as you weld the tube, so you don't need any filler and the tubes are perfectly aligned. I assume you butt welded the tubes. You'd be suprised how the uniform filler will make your welds look good.
-Use an old bicycle inner tube to check for leaks. Take one end and clamp it with a worm clamp to the tube and fold the other end up a few times and secure it with a clamp. Use two tubes if you can't get one to reach. Fill it up with air from your compressor and look for leaks with some soapy water.
-Make yourself a back purge setup for the inside of the weld to make sure it is covered in argon.
-Clean the zinc or whatever is on that metal befor you weld it and it will turn out a lot better. It isn't real good for your health to breath those fumes and it is real easy to contaminate the tungsten with it. Try and remove on both sides of the metal if it is coated.
-Get a very bright light and iluminate the weld . You'll be amazed at how much difference it makes. A reflective lens will help too. I have a pair of glasses with a focal length ideal for welding. Friends of mine use 'cheaters' to good effect. Try different lens density and see if there is one you like better
-get a 'gas lens' for your TIG torch
- Your fit-ups should be line to line. That sometimes makes the joint hard to see, so I'll sometimes put a indelible pen mark about 3/16 from the joint as a guideline to keep the weld straight.
-Tack the tube in three places before you start welding. I try to weld between the tacks continuously.
-Use more filler, or
- Holley or Hooker make a 'welding ring' that you can buy for cheap that is basically a sleeve with an upset in the middle that is consumed as you weld the tube, so you don't need any filler and the tubes are perfectly aligned. I assume you butt welded the tubes. You'd be suprised how the uniform filler will make your welds look good.
-Use an old bicycle inner tube to check for leaks. Take one end and clamp it with a worm clamp to the tube and fold the other end up a few times and secure it with a clamp. Use two tubes if you can't get one to reach. Fill it up with air from your compressor and look for leaks with some soapy water.
-Make yourself a back purge setup for the inside of the weld to make sure it is covered in argon.
10-16-2005, 09:03 AM
#23
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Originally Posted by Brains
I didn't photo the inside, but it did indeed flow. I was actually surprised how it looked quite a bit like the top! I still need to work on torch position as I work around a round pipe, I find myself not at the correct angle in relation to the tube as I travel -- I need to learn to follow the curve with the torch instead of "stepping" the angle as I move. I also need to get my motion a little better, I'm currently more or less moving in a steady forward direction and only pausing slightly to add filler. From what I've read, it says the proper motion is to back up, dip the rod, and then move back over the puddle again?
I guess all my years of working over a soldering iron made it a little easier to pick up tig pretty quickly.
I guess all my years of working over a soldering iron made it a little easier to pick up tig pretty quickly.
10-16-2005, 12:32 PM
#24
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Thanks guys, welded some stainless last night and learned exactly what you guys are posting 
I've got 3/32" rod, and its too thick IMHO. Every time I'd dip, the puddle would widen considerably -- so I used filler only when I saw the joint "droop." I had the heat down to ZERO and I still was not going full pedal. I managed to stick the tungsten in the weld pool twice 
I spent a good amount of time on joint prep. I cut the tubing in a chop saw, then took a carbide burr to clean up the ends. I'd prep back about 1/4" to ensure there was nothing but bare stainless (didn't do that with the aluminized pipe I posted pics of). The fitment was perfect, I couldn't see a gap anywhere before I started welding and it made it a lot easier. I was welding directly under a bright flourescent light and I could see the joint relatively well. I like the idea of using a pen to mark a guide, because there were a couple times I was on the edge of the joint rather than in the middle
How long should a 40cu.ft. cylinder last me? I didn't even finish the weekend before it went dry! I've got the regulator set to 20CFH. Guess its time to step up.
I've got 3/32" rod, and its too thick IMHO. Every time I'd dip, the puddle would widen considerably -- so I used filler only when I saw the joint "droop." I had the heat down to ZERO and I still was not going full pedal. I managed to stick the tungsten in the weld pool twice I spent a good amount of time on joint prep. I cut the tubing in a chop saw, then took a carbide burr to clean up the ends. I'd prep back about 1/4" to ensure there was nothing but bare stainless (didn't do that with the aluminized pipe I posted pics of). The fitment was perfect, I couldn't see a gap anywhere before I started welding and it made it a lot easier. I was welding directly under a bright flourescent light and I could see the joint relatively well. I like the idea of using a pen to mark a guide, because there were a couple times I was on the edge of the joint rather than in the middle
How long should a 40cu.ft. cylinder last me? I didn't even finish the weekend before it went dry! I've got the regulator set to 20CFH. Guess its time to step up.
10-16-2005, 01:15 PM
#25
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I was tacking my pipe joints and then using a sharpie right down the joint before welding it up. Did not seem to affect the cleanliness at all. I went through my first couple tanks pretty quick. Got a bigger one. You figured out that its a light foot on the pedal. Are you prepping the tugsten to a point? A cheap tailpipe expander will be your best freind. It will round the pipes and make better joints.
Also a disk sander works well after the cutting the pipe.
Also a disk sander works well after the cutting the pipe.
10-16-2005, 05:47 PM
#26
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Yes, prepping to a point and I usually flatten off the very tip leaving maybe .005" flat. I have a cheap tailpipe expander, but already stripped the damned bolt I'll fish around at work for some super grade 8 (200,000 psi tensile) bolts to replace it with. Wished I had one yesterday, I straightened out the pipe by hand (small body hammer and dolly).
Thanks for your help and insight in this thread guys, I REALLY appreciate it !!!
I'll fish around at work for some super grade 8 (200,000 psi tensile) bolts to replace it with. Wished I had one yesterday, I straightened out the pipe by hand (small body hammer and dolly).Thanks for your help and insight in this thread guys, I REALLY appreciate it !!!
10-17-2005, 10:22 AM
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i can't even keep track of how much argon we use! i've gotten in the habit off turning of the valves after every time i use it(no one else in the shop will, oh well) cuz they all leak to a certain extent.....we kept going through 75/25 in the mig like it was water, until finally i looked at the gas gauge and realized it had been topped out at 50cfu
it sounds like you are right in step with what you need to know to do your projects! the only thing i would add is that "back purging" is really only required for butt welds of metals like titanium and stainless steel that are super-easily contaminated by oxygen.......even then i don't think it is something to worry about in an exhaust system(especially if you are doing a lap weld on a slip fit tube), although perhaps if you are gonna see high pressures in a turbo setup it may be useful.....in that case, it has also been shown that a tri-mix(helium/argon/co2) gas with a high silicon content filler can be used for a strong weld without a backing gas......
hey ls1sandrail,
i've never used a gas lens, so i was wondering what effect it has? i know it's supposed smooth the gas flow, so does it help you control the arc better? do you only use it with larger cups? thanks in advance
josh
it sounds like you are right in step with what you need to know to do your projects! the only thing i would add is that "back purging" is really only required for butt welds of metals like titanium and stainless steel that are super-easily contaminated by oxygen.......even then i don't think it is something to worry about in an exhaust system(especially if you are doing a lap weld on a slip fit tube), although perhaps if you are gonna see high pressures in a turbo setup it may be useful.....in that case, it has also been shown that a tri-mix(helium/argon/co2) gas with a high silicon content filler can be used for a strong weld without a backing gas......
hey ls1sandrail,
i've never used a gas lens, so i was wondering what effect it has? i know it's supposed smooth the gas flow, so does it help you control the arc better? do you only use it with larger cups? thanks in advance
josh
10-17-2005, 12:02 PM
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I'm going to upgrade to a 125cu.ft. cylinder today, but probably keep my little 40cu.ft. and get it filled as a spare, or for backing gas.
10-17-2005, 09:29 PM
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Originally Posted by RFERG43
A gas lense will remove the turbulence from the gas stream and you can have more stick out on tungsten.
10-18-2005, 08:09 AM
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Originally Posted by Brains
With 3/32" and a #7 cup, I'm at ~18CFH which is ~8.5lpm .. Seems to be working well so far?
10-18-2005, 07:57 PM
#35
If my tungsten is extended to get in a crevice or tight fit on a cage, Ill turn it up to 50 or 60 cfh.
Brian, I use .040 and .060 T308 rod. If youre welding 304, you want to use a grade higher stainless. 312 use 321 rod, 321 use 347 rod, ect.
I Never use 3/32 or 1/8th rod, thats just gigantus. Aluminum, I use thicker stuff, because you work 2x as fast, and it takes more rod, and the welds are 2x the size.
TIGDEPOT.com has some nice backpurging ideas, but they can be pricey.
Brian, I use .040 and .060 T308 rod. If youre welding 304, you want to use a grade higher stainless. 312 use 321 rod, 321 use 347 rod, ect.
I Never use 3/32 or 1/8th rod, thats just gigantus. Aluminum, I use thicker stuff, because you work 2x as fast, and it takes more rod, and the welds are 2x the size.
TIGDEPOT.com has some nice backpurging ideas, but they can be pricey.
10-20-2005, 10:56 AM
#37
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Originally Posted by smokinHawk
anyone know a good way to backpurg when welding stainless pipes.
what do people do, fill the tube up eith argon and cap off some how? what is used to cap off?
what do people do, fill the tube up eith argon and cap off some how? what is used to cap off?
I got another regulator/flowmeter and a 3000 psi rated tee, then screwed the two regulator/flowmeters together and hung them on the argon bottle. One for the welding machine, one for back purging, separately adjustable. Welding houses sell dual setups ready-made, but they are ~$100.
When making my headers/exhaust, (304L stainless) I simply capped off one end of the tube with alum foil and a wire tie, and stuck the hose from the flowmeter in the other end of the tube and sealed it with masking tape. Poke a tiny hole in the alum foil, put that end of the tube higher than the rest of the tube, (argon is heavier than air) and set the flowmeter to around 10-12 cfm. Works great. No more black sugar inside now! The only down side is y'all only though you were going through a bottle of gas fast before.
11-07-2005, 04:41 AM
#40
Originally Posted by jdustu
i don't weld aluminum too much, but sometimes it can be fickle....
i work for dcx and our union has a training center set up that we can go to for different classes, so whenever i get the chance i go there for their welding offerings.....anyways, the last time i was up there a guy from work asked me to weld some al brackets onto some al skis, so i said no problem....the first couple of welds were pretty as pie, then the next couple i couldn't get to melt together worth anything, and it was kind of hit or miss on each weld(wouldn't start a puddle, got dirty, ect.)...so i had the instructor, who has over 50 years of experience, take a look at it..we checked the gas, the gun, the machine, the electrode, and he still didn't have any more luck than i did........the only explanation was that possibly the metal itself just wasn't that good of aluminum, and perhaps it was contaminated.......i got it together, but it wasn't so pretty
last week i welded some aluminum brackets, pry 3/8 thick and it was in a tight spot so i tried using a 1/16 electrode sticking out of a #4 cup....i kept blowing up the tungsten so i went back to the 1/8(we don't have any 3/32 right now) in a wider cup, stuck it out of the cup a little more than i would normally(so i could reach the spot to be welded) and cranked the gas up to 35 psi instead of 25, and it worked great......
make sure you have a good ground, try using a bigger electrode, and if you are using a brush to clean the material make sure it has ONLY been used on aluminum....i welded a r/c nitro car exhaust one time, i think that's pretty much the only time i've had to use the 1/16" tungsten, with the thicker stuff the electrode can't take the heat generated from a/c and continuous high frequency.....
i work for dcx and our union has a training center set up that we can go to for different classes, so whenever i get the chance i go there for their welding offerings.....anyways, the last time i was up there a guy from work asked me to weld some al brackets onto some al skis, so i said no problem....the first couple of welds were pretty as pie, then the next couple i couldn't get to melt together worth anything, and it was kind of hit or miss on each weld(wouldn't start a puddle, got dirty, ect.)...so i had the instructor, who has over 50 years of experience, take a look at it..we checked the gas, the gun, the machine, the electrode, and he still didn't have any more luck than i did........the only explanation was that possibly the metal itself just wasn't that good of aluminum, and perhaps it was contaminated.......i got it together, but it wasn't so pretty
last week i welded some aluminum brackets, pry 3/8 thick and it was in a tight spot so i tried using a 1/16 electrode sticking out of a #4 cup....i kept blowing up the tungsten so i went back to the 1/8(we don't have any 3/32 right now) in a wider cup, stuck it out of the cup a little more than i would normally(so i could reach the spot to be welded) and cranked the gas up to 35 psi instead of 25, and it worked great......
make sure you have a good ground, try using a bigger electrode, and if you are using a brush to clean the material make sure it has ONLY been used on aluminum....i welded a r/c nitro car exhaust one time, i think that's pretty much the only time i've had to use the 1/16" tungsten, with the thicker stuff the electrode can't take the heat generated from a/c and continuous high frequency.....
i turned the gas up to 35cfm vrs the 20-25cfm i was using before.
got a couple of wire brushes for aluminum, cleaned it some (even though it looked cleaned for just in case)
welded, cleaned, welded again, cleaned again, so every time i stopped i cleaned it.
The welds look ALOT nicer, welded awhole lot easier, wouldnt corrode and puddled alot better.
Definatly a major improvement.
thanks for the help.