Welding a Small Part

[Teachu2]

I just bought this scratch start Tig torch a couple months ago. Really like it.:thumbsup:
WP 26V 25R 25' 200Amp Air Cooled TIG Welding Torch Gas Valve Ready to Go Package | eBay
http://www.ebay.com/itm/140514184508?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT

That looks pretty sweet.

 

[Fawken]

Just to clarify, I in no way claim to be an expert welder. I think I'm pretty darn good with a stick machine and am catching on to TIG pretty well. Here is what I've used for the past 42 years and it has never missed a beat. I think it is a Lincoln, but never opened it and really never thought about it until recently:


Here is the WWII knife I referenced. Belonged to my dad and I found out that one of the grandkids must have broken it playing with it. Mom couldn't find the parts so I had to make new ones. Had to use 1/16" stainless steel rods to build the tang and tap off the tiny studs that hold it together:

 

[CNC Dan]

The oil is an old trick that a guy who makes custom springs taught me. I used to just cool things down with water and you do get some tempering, but the oil works much better. Now on larger pieces you just have to let the air cool it down and be more careful with over heating.

I may be nitpicking here, but when you cool hot metal it's called quenching. It will make the metal harder, possibly too hard. The metal can then be re-heated to a lower temperature to remove some of the hardness, and give it more toughness. That re-heating process is called tempering.

 

[Shield Arc]

That looks pretty sweet.

You can even weld aluminum with them.

 

[Fawken]

I may be nitpicking here, but when you cool hot metal it's called quenching. It will make the metal harder, possibly too hard. The metal can then be re-heated to a lower temperature to remove some of the hardness, and give it more toughness. That re-heating process is called tempering.

Never knew. Too bad you're so far North we could use another machinist/fabricator in the shop. I think the greatest asset to these kinds of forums is when people share their ideas and knowledge.

 

[downsizingnow48]

On TIG that looks pretty tempting, as if I need any help acquiring tools. I'll have to look at that a bit.

Quenching I could do. Drop it in the bucket of oil, I got that. Tempering, what do you do?

 

[Teachu2]

On TIG that looks pretty tempting, as if I need any help acquiring tools. I'll have to look at that a bit.

Quenching I could do. Drop it in the bucket of oil, I got that. Tempering, what do you do?

Heat it evenly to a light straw color, then air cool.

 

[downsizingnow48]

Tempering -- OK that I can do - many thanks.

On TIG, good grief. This is from that ebay listing:

"Tungsten Electrodes
Pure, Thoriated, Ceriated, Lanthanated Tungsten electrodes with varied diameters"

I give up, have just barely got used to MIG.

 

[Big Barn]

I may be nitpicking here, but when you cool hot metal it's called quenching. It will make the metal harder, possibly too hard. The metal can then be re-heated to a lower temperature to remove some of the hardness, and give it more toughness. That re-heating process is called tempering.

Ha ha. They taught me that in high school. Thanks for the refresher, Dan!

Terry

 

[Teachu2]

Tempering -- OK that I can do - many thanks.

On TIG, good grief. This is from that ebay listing:

"Tungsten Electrodes
Pure, Thoriated, Ceriated, Lanthanated Tungsten electrodes with varied diameters"

I give up, have just barely got used to MIG.

Probably not the best time to learn a new process....

 

[k0ua]

Tempering -- OK that I can do - many thanks.

On TIG, good grief. This is from that ebay listing:

"Tungsten Electrodes
Pure, Thoriated, Ceriated, Lanthanated Tungsten electrodes with varied diameters"

I give up, have just barely got used to MIG.

Get some Lanthanated or Ceriated .. I use Lanthanated 1/16 for most of these small things. Blue band. It is not all as complicated as it first seems. TIG is the most enjoyable process of all. Not very fast though. MIG eats its lunch for good beads quick.

 

[Teachu2]

I agree with kOua completely.

 

[DuckSlayer1017]

If I remember correctly from my material science class oil quenching cools the steel slower than water so the hardness is not quite as high as water quenching. It also makes the steel less brittle. Annealing or tempering is done by heating to a lower temperature for a period of time then air cooling. Every steel has a different annealing time and temp. Another trick with the used oil is that the steel will absorb some of the carbon from the oil and become stronger. If I'm wrong let me know, it's been 17 years since I took that class.

 

[Fawken]

If I remember correctly from my material science class oil quenching cools the steel slower than water so the hardness is not quite as high as water quenching. It also makes the steel less brittle. Annealing or tempering is done by heating to a lower temperature for a period of time then air cooling. Every steel has a different annealing time and temp. Another trick with the used oil is that the steel will absorb some of the carbon from the oil and become stronger. If I'm wrong let me know, it's been 17 years since I took that class.

Don't know the science, but you could be right. The dirtiest oil makes the absolute best springs.

 

[Mace Canute]

That's the sort of job that begs to be done on a lathe but welding up a clevis is a good work around. I don't gas weld but a couple of friends do and the jobs they do look fantastic.

 

[Shield Arc]

Another trick with the used oil is that the steel will absorb some of the carbon from the oil and become stronger. If I'm wrong let me know

I remember an engineer telling me that once.

 

[Mysfyt]

Another tip for welding anything is to clean the metal with a grinding or sanding disc B4 you weld. You will see the difference on the edges of your MIG puddle. A 4-1/2" grinder should be a mandatory piece of equipment to go with any welder. Just my .02

 

[Fifelaker]

Dirty oil has a bit of carbon in it as a by product from the combustion process of the engine. Tempering in dirty oil, a little of the carbon is transferred to the surface of the steel raising the carbon content which makes it harder and more brittle. Tempering makes it less brittle but it still retains the carbon it picked up in the quench which makes it stronger. It won't raise the carbon content much but it does raise it some. Even clean oil will raise it some because you are burning the oil when the hot steel hits it.

 

[downsizingnow48]

That's the sort of job that begs to be done on a lathe but welding up a clevis is a good work around.

Mace hi. I thought of making it in one piece on a lathe. Either way get to the same place. This way I don't have to do 9/16" of internal 3/8-24 threads, or cut flats to take a wrench. Probably other ways to skin this cat too!

 

[downsizingnow48]

And also now I learned about quenching and tempering, that is good to know. Plus learned some tricks on how to weld that small part that I wouldn't have thought out on my own.