Learning to Tig questions

[triathloner]

So I have a Miller diversion 165 and am currently practicing on some tubes from two old road bikes that were damaged. I have tried doing a slip joing as one of the tubes fits tightly into another and had some halfway decent success. The few miters I have done fit well but when I tried welding them I have trouble controlling a puddle and burn through easily, it seems any less heat I have a hard time getting a puddle and adding filler. I am using the tungsten that came with the welder and am not sure what size filler I should be using on chromoly. Any pointers you experts can lend? Are there any charts that list sizes of filler or tungstens to use? Thanks Al.

[Alistair]

So I have a Miller diversion 165 and am currently practicing on some tubes from two old road bikes that were damaged. I have tried doing a slip joing as one of the tubes fits tightly into another and had some halfway decent success. The few miters I have done fit well but when I tried welding them I have trouble controlling a puddle and burn through easily, it seems any less heat I have a hard time getting a puddle and adding filler. I am using the tungsten that came with the welder and am not sure what size filler I should be using on chromoly. Any pointers you experts can lend? Are there any charts that list sizes of filler or tungstens to use? Thanks Al.

I am not an expert on tig welding, but I'll pass along what I know. For tubing around 0.030" wall thickness I've been using the following:

1/16" 2% Thoriated tungsten (I know some builders prefer 3/32"), sharpened to a long needle point on a dedicated diamond cup grinding wheel eg.,
6 x 1 2" Diamond Cup Grinding Wheel D6A2C 150 Grit 6A2C | eBay

and polished on a Scotch Brite EXL deburring wheel eg.,
https://beta.mscdirect.com/product/01174721

For filler I'm using 0.045" ER70-S2 rod (I know some builders prefer 0.035").

The torch is one of the smaller ones (CK 130) with the large gas lens and no. 8 cup, although I've been trying out no. 10 cups too. Argon flow is 15-18 cfh.

Regarding your machine, I have read that the Diversion machines don't have great low amp arc stability. For an experienced welder this might not be a problem, as they will typically run beads faster and hotter. For a beginner it might make things tricky. You'll probably want that low end arc stability as you work your way up to being able to run a bead with more authority.

Hope this helps.

Alistair.

[RCP FAB]

Regarding your machine, I have read that the Diversion machines don't have great low amp arc stability. For an experienced welder this might not be a problem, as they will typically run beads faster and hotter. For a beginner it might make things tricky. You'll probably want that low end arc stability as you work your way up to being able to run a bead with more authority.

Not sure where you heard that. Check this review out Tig Welder Demo

If you are using the torch control, I would get a foot pedal for it.

I weld my frames with a Diversion 180

[Alistair]

Not sure where you heard that. Check this review out Tig Welder Demo

If you are using the torch control, I would get a foot pedal for it.

I weld my frames with a Diversion 180

I'm not sure where I read it either, but I remember coming across it a few times when I was researching welders. I recall that being one of the knocks on those machines which I thought was a shame, because they seem like they have a really good combination of features, for a good price.

I'm much more inclined to listen to the experience of someone using one of these machines for building bikes though, than some comments on a random welding forum.

Good to know about this because the Diversion has a lot going for it from what I can tell from the spec's.

Alistair.

[triathloner]

Thanks for the help, wow it's nice to see that weld so I know it's capable on my machine, though a little dis-heartening to realize that I still have a lot to learn. Thats ok, though I have a heated shop and need something to do in the Minnesota winters. Now I will be ordering a few tungstens and checking my rod size. Thanks. Al.

[RCP FAB]

If you are ordering tungsten's get a pack of 1/16" 2% Lanthanated. If you have some thoriated they will work also, but lanthanted is a better blend.

[suhacycles]

I first learned TIGing with pulse but I'm wondering if there any folks who don't use the pulse feature. Any tips for those learning without pulsing?

[RyanHeller]

I first learned TIGing with pulse but I'm wondering if there any folks who don't use the pulse feature. Any tips for those learning without pulsing?

My advice is to learn without pulse. It helps develop a rhythm for feeding the filler on your own, and not relying on the machine to do it for you. Also, pulse on lower grade machines can actually be more difficult because of the lack of adjustability, particularly on the low side. It leads to your puddle turning cold and makes it almost impossible to have a quality weld.

[Zukas Cycles]

Not sure where you heard that. Check this review out Tig Welder Demo

If you are using the torch control, I would get a foot pedal for it.

I weld my frames with a Diversion 180

So glad I saw your reply! I just bought a diversion 180 and feared the worst but seeing your work has motivated me to keep on practicing!

[Doug Fattic]

I've made a few tig welded frames over the years. I took the first titanium welding class UBI offered 20 years ago. Only experienced framebuilders attended that class. I was the only guy that hadn't tig welded before. Back then UBI had Miller Maxstars with high frequency start and pulsers. After class when I wanted to learn how to weld steel, I needed to practice with short sections of mitered tubing to get the hang of it.

As a teacher I recommend a sequential level of difficulty in order to catch on how to weld. Master easy before trying something more complex. The principles of welding aren't much different than brazing with a heat source melting a filler rod. Start with the simplest possible straight pass without filler to get the feel of the torch. You can do this right along a section of .035" tube of almost any diameter. You begin to get the hang of having a torch in your hand and keeping a constant distance at a constant speed. I actually recommend using a pulser at the start because it is an automatic heat control device that eliminates one distraction. The principle being that a learner has a hard time keeping track of 2 things at once. If they start thinking of how to operate their foot while keeping their hands moving at the right speed, etc. they can become a bit overwhelmed. Once a person catches on to melting a straight line, they can start adding filler. Eventually one can start doing short mitered joints.

I found it easier when doing my steel practice joints to use a smaller tungsten (like .045") and filler rod (.035") if I remember right. It is sort of the same principle I use when I start students brazing with a smaller tip so it doesn't heat up so fast and gives them more time to react at what is going on. I got the rod from my framebuilding friend John Cherry so it wasn't the standard stuff. I used to paint a lot of frames for him. One other practice helper I discovered was to hold the practice joints in a Panavise that could be swiveled into about any position. I learned that trick from Gordon who used to be a welder at Moots. I replaced its regular jaws with aluminum V jaws that better held the tubes. I also used wooden blocks (sometimes in a stack) to support and help position my torch hand. They were actually halves of pieces eventually designed to make into tube holding blocks.