DIY Welding Questions

I think it might be nice to have a thread about welding questions. Questions about the process and how to trouble shoot. It might make a nice sticky.

Please anybody chime in and answer the questions others have. I believe welding is an art form and what works for one, may not work for the other. This could be a great info source due to the diverse crowd and experience levels here.

This was posted in another thread. So I am going to try and answer here.

LooyvilleLarry said:

This is for a new HLT (stepping up from a 10g cooler).

There are 5 1/2 couplers on it, all pulled. Some of the tig welds were real nice, others -erm, not so much.

Equipment - HF Tig, WP17 Torch w/ gas lens, 1/16" 2% Thor, 40a, 17cf Argon.
Most were friction welded. You'll see some "drops", because I used a piece of filler to start the arc (no HF here).

Here are a couple of pics. Comments welcome (I easily laugh at myself)..

Now for the tough question. The electrical (1 1/2") coupler. should I try and weld this in, or go with a weldless on this one.?

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I will start by asking you a couple questions.

Do you have a foot pedal or a rail type torch to control the heat while your welding?
If you pulled the coupling though, why do you have weld down so low?
Are you using any purge?
How did you prep the weld area and coupling? I see the trails of a grinding disc.


In your equipment you list the welder. Who makes the welder? It starts off with HF. That too me makes me think it is a HF unit. Does it not work? I am not familiar with using a piece of filler to start the arc. I have always just scratch started a TIG unit without HF. (Lift arc) The electrode is right IMO, the amps are right maybe a little cold. That depends on whether or not you have control. What size is your gas lens and cup? Depending on what size you have will change my mind on the gas flow number of 17 CFH. Any breeze blowing while you were welding?

On the 1 1/2" coupling, I would weld it in.

GreenMonti said:

This was posted in another thread. So I am going to try and answer here.
I will start by asking you a couple questions.
Do you have a foot pedal or a rail type torch to control the heat while your welding?

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No control, it is a Harbor Freight Tig with a WP17 torch

If you pulled the coupling though, why do you have weld down so low?

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I think it has to do with control issues. I was trying to melt the two pieces right at the line. I also felt that the arc was too wide.

Are you using any purge?

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I used Solar Flux on the back side

How did you prep the weld area and coupling? I see the trails of a grinding disc.

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I prepped with a brown 3" scotchbrite, followed by SS brush (only used for SS Keg work). Acetone wipe. The grinder was post weld.

In your equipment you list the welder. Who makes the welder? It starts off with HF. That too me makes me think it is a HF unit. Does it not work? I am not familiar with using a piece of filler to start the arc.
, the 249 one (http://www.harborfreight.com/240-volt-inverter-arc-tig-welder-66787.html). I was having problems with the scratch start sticking, so somewhere I read to use the (grounded) tip of the wire as a start. That seems to work well.

I have always just scratch started a TIG unit without HF. (Lift arc) The electrode is right IMO, the amps are right maybe a little cold. That depends on whether or not you have control.

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What size is your gas lens and cup? Depending on what size you have will change my mind on the gas flow number of 17 CFH. Any breeze blowing while you were welding?

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45V25 (1/16).
Cup is a 9 I think.
I did have a couple of times that breeze hit (I was inside garage, but doors kept opening ), but I stopped pretty quick on that.

@GreenMonti do you have any suggestions for pulse settings when welding on kegs. I already did my welds and I'm kinda sorta happy with them. I think I used too thin of filler, .45 vs 1/16th

Welder is a Dynasty 300dx with 9 series torch.

Also, I've noticed lately that I am having some trouble with HF starting when the metal is cold. I will often have to touch the electrode to the metal to get it going but once the I'm welding I can stop and then start again without trouble. Could this be poor grounding or is a board in the welder going? Think the manufacture date of the welder is 1998 or so.

LooyvilleLarry said:

No control, it is a Harbor Freight Tig with a WP17 torch


I think it has to do with control issues. I was trying to melt the two pieces right at the line. I also felt that the arc was too wide.



I used Solar Flux on the back side


I prepped with a brown 3" scotchbrite, followed by SS brush (only used for SS Keg work). Acetone wipe. The grinder was post weld.


45V25 (1/16).
Cup is a 9 I think.
I did have a couple of times that breeze hit (I was inside garage, but doors kept opening ), but I stopped pretty quick on that.

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Your prep sounds good to me. I don't bother with the wire brush after the scotch brite. Just the acetone wipe. Wire brush while the weld is still warm.

I like to run the weld just a bit biased to the coupling. It is heavier and can take a little more input. It also needs it to weld the different thickness together smoothly. How far away from the material were you holding the tungsten? You should be right in there for a nice small weld. How did you grind the tungsten? Like a needle or more blunt?

I would turn up the gas a touch. Give it about 20-22 CFH. How far out is the tungsten from the end of the cup? The bigger the cup the further out you can go. That is the main reason I use the large diameter gas lens and a number 12 cup.

I also see in your pics a pit in the end of the weld. It is gonna be more though for you to get a nice smooth end on your welds as you can't control the heat and tail out. That pit leaves you prone to a leak. I would try placing a drop of filler at the end and then go backwards on the weld and pull the torch away from the material. This should lessen the focus of the arc and allow you to get out of there without a pit/pin hole. A small dimple is ok. Its gonna take practice, its hard to enplane. You may also find a better way for you to do it.

Haggismaximus said:

@GreenMonti do you have any suggestions for pulse settings when welding on kegs. I already did my welds and I'm kinda sorta happy with them. I think I used too thin of filler, .45 vs 1/16th

Welder is a Dynasty 300dx with 9 series torch.

Also, I've noticed lately that I am having some trouble with HF starting when the metal is cold. I will often have to touch the electrode to the metal to get it going but once the I'm welding I can stop and then start again without trouble. Could this be poor grounding or is a board in the welder going? Think the manufacture date of the welder is 1998 or so.

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Nice welder. Good for you. I can't afford one.

This depends a little IMO. Pulse settings will vary from weldor to weldor. Reason is we all like to run at different speeds. Also, I know a few that like to use the pulse to achieve the look of the weld.

If your not trying to get the look of the weld out of the pulse setting, then you might try this.

Amp setting= 68
PPS setting= 60
Peak setting= 45
Background setting= 10

I like those numbers when I weld a pre-cooler duct at work. It is .050" thick 718 Inconel. I weld the pieces in a butt weld fashion and I get little distortion with backing shoes on the joint. I use .025" filler. I also like to use the .025" filler when I weld up my keg conversions. I would use .035" filler if I was welding on a coupling without the pull out. So I think your .045 was fine. IMO the heavier the filler the more difficult you make the weld. The thinner material needs very little heat input and if you go sticking a large diameter fill rod in there, its just gonna suck up all the heat and lay on top. You then correct this by using more heat. Not good.
If your looking to make the bead look like a row of dimes using the pulse. You gonna need the PPS down around .5 or so. I don't weld this way so I can't say for sure. The titanium guys at work like it this way for their fillet welds cause the filler gets real sticky when it warms up. I don't. I like the dip method and, I like to think I am winning some kind of a war when I weld Titanium.:cross:

I know exactly what your talking about on the arc. Our Max Stars do it all the time. It is generally linked to a poor ground but, I do believe that Millers inverter machines have a bit of an issue with this. I have learned to just deal with it. One thing I do when I am welding on thin material, (.014" thick) I will start the arc on something and let the tungsten get hot. Then I stop, move to my piece and it will start right up. It is rare that I need to scratch the tip if I do this. 2% Thoriated tungsten is not very happy when being used with a pulse setting either. I get a little halo/mushroom head like build up on mine. It builds up fast when I am using the pulse.

Anyone here use O/A? I recently got a lincoln port-a-torch (actually made by Harris) and have been learning when I get the time. I've been working with mild steel as the puddle is much easier to manipulate....anyone got tips for gas welding SS? I've heard it's nearly impossible....I bet i'd get better results with brazing, but I don't want to overheat the stainless on accident and weaken it.

ScubaSteve said:

Anyone here use O/A? I recently got a lincoln port-a-torch (actually made by Harris) and have been learning when I get the time. I've been working with mild steel as the puddle is much easier to manipulate....anyone got tips for gas welding SS? I've heard it's nearly impossible....I bet i'd get better results with brazing, but I don't want to overheat the stainless on accident and weaken it.

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I would stick to brazing myself. Reason being...Saftey Silv 56 silver braze is NSF certified and it melts at 1200*F. If you gas weld it, you will need to get it up to 2550-2640*F to get your puddle. So, by silver brazing it you would be putting less heat into your parts. You can buy the Saftey Silv 56 from the depot for about $40. That comes with the flux you need too. IIRC, the catch is they only sell it on-line

What pieces are you going to join together?

@GreenMonti

Thank you for the advise, much appreciated. I got the welder on eBay some years ago for a steal (well it was still expensive, but much cheaper then retail, or most used ones) I almost feel like this machine must be cheating, I think it makes up for my total lack of skill.

Another question if you don't mind. I feel like I can do fillet welds pretty well and can get them to have that stack of dimes look, but anything round is a nightmare, I just have a real hard time positioning the electrode so that I can follow the curvature of the joint. Is it normal to have to reposition a lot for smaller tube items (welding some 1/2" ferrules onto 1" tube now.)

Haggismaximus said:

@GreenMonti

Thank you for the advise, much appreciated. I got the welder on eBay some years ago for a steal (well it was still expensive, but much cheaper then retail, or most used ones) I almost feel like this machine must be cheating, I think it makes up for my total lack of skill.

Another question if you don't mind. I feel like I can do fillet welds pretty well and can get them to have that stack of dimes look, but anything round is a nightmare, I just have a real hard time positioning the electrode so that I can follow the curvature of the joint. Is it normal to have to reposition a lot for smaller tube items (welding some 1/2" ferrules onto 1" tube now.)

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Yea, any round object is a pain. When doing flanges and such, a weld position er is a great tool. But, I only get that luxury at work. I don't even try to go far anymore. That's another beni to TIG welding. You get too sit there and bring it all back and then keep going. When I weld on couplings, generally I wont make it a full 1/4 of the way around in one pass. This is where being really good at your starts and stops comes in.

GreenMonti said:

Yea, any round object is a pain. When doing flanges and such, a weld position er is a great tool. But, I only get that luxury at work. I don't even try to go far anymore. That's another beni to TIG welding. You get too sit there and bring it all back and then keep going. When I weld on couplings, generally I wont make it a full 1/4 of the way around in one pass. This is where being really good at your starts and stops comes in.

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Yeah, I make takes me about 5-6 turns to get it all the way around. Thanks again.