[WerkSpace]

I've been kicking around the same idea, but with a section of Pyrex test tube.

Well, here it is! Practical, probably not. But it sure is cool!! I can't wait to give it a go and see how it works. -Jonathan

[Superiorwelding]

Well I was able to test out my copper cup tonight and have mixed feelings. I did not have a problem with the arc jumping through the cup if I was fast on the arc start. It only jumped when I had the cup beside a third hand and it was only or a split second. Once the arc was established I could touch the cup to anything and had no problems. I did not expect the Scotch Brite to hold up to any heat and it didn't. The beads in the picture were with the machine set at 100 amps but I have no idea where I actually was. The top bead was a normal weld and the bottom was a experiment of holding the TIG cup backward in a attempt to allow the shielding to flow over the already laid down weld. In order to get this set up to work at all I had to turn the gas flow to 30 cfh, anything much lower did not work. I had no problem with heat from the copper but I didn't weld for all that long. AC did not work at all, that was a total failure.

Lesson learned; While the cup set up looks sweet it is not practical in it's current configuration. It would work fine if it had a real gas lens but I think you would still need a higher gas flow. I heard Collin (ToxicFab) say he is up around 25-30 cfh so I don't think I am out of the park. The real drawback to putting in the gas lens would be you would have direct power to the cup.

So, I came up with another idea, 3D printer. Why not take my design I discribed earlier and have it 3D printed? I might see if Kevin Caron would be interested in giving it a shot.
-Jonathan

[Oscar]

SS mesh layers with a collet body in the middle as a tungsten guide

[dirtmidget33]

Superiorwelding, you said the AC arc was a failure I have my theories as to what the AC arc tried to do but since you have real world experience now what did it do? Some of my easiest assumptions would be. I would assume it was an erratic arc or I could see it jumping an arc from the collet body to the cup. Because if I understood your design you used the CK gas saver collet body and slid the cup over that. So oring on the collet body was your insulator. especially true if cup made contact with any ground. Correct me if I am wrong on the AC arc characteristics or your design.

As for the scotchbrite use for lens, I know there is at least one of the custom cup builders either using that material or one similar to it, but the biggest issue I have with it is you do not get a good true laminar flow With it. I was surprised to see new cup makers trying to go with using a porous substance to do that. Especially when the testing has already been done during the development of gas lenses and it was proven that multiple fine screens align the molecules up far superior. I could prolly find an article again where I read about the use of these type of porous spongy filters being tried I know I have a link somewhere.

On a side note was wondering if you could use a spray on ceramic coating on inside to help insulate your copper cup so you could use the gas lens without making the cup live. If coating gets scratched bad enough won't do any good but it's an option. The ceramic coating I refer to is what we use on pistons. Takes heat very well and the ones I tested with a ohm meter did not carry continuity.

[Superiorwelding]

dirtmidget33,
I didn't put a lot of thought into why the AC didn't work but here is what happened. When I first lit up the puddle itself looked like I was on DC. I quickly stopped and checked my machine and I was in fact on AC. I tried again and it was so erratic that after a few more attempts I just stopped. That and the fact the Scotch Brite material melted down into my puddle. I would have to guess two things. First, as you mentioned, the arc was in fact arcing across the cup then it headed back toward the tungsten/cup/torch and second I was on 3/16" material at that point with the machine set at 180 amps so with the Scotch Brite material melting into my tungsten I don't think that helped matters.

I do have that ceramic anti spatter stuff that I could try. That sounds like a good theory. I will give this a few more attempts before putting it out to pasture. I like learning and experimenting.
-Jonathan

[Oscar]

Superiorwelding, you said the AC arc was a failure I have my theories as to what the AC arc tried to do but since you have real world experience now what did it do? Some of my easiest assumptions would be. I would assume it was an erratic arc or I could see it jumping an arc from the collet body to the cup. Because if I understood your design you used the CK gas saver collet body and slid the cup over that. So oring on the collet body was your insulator. especially true if cup made contact with any ground. Correct me if I am wrong on the AC arc characteristics or your design.

As for the scotchbrite use for lens, I know there is at least one of the custom cup builders either using that material or one similar to it, but the biggest issue I have with it is you do not get a good true laminar flow With it. I was surprised to see new cup makers trying to go with using a porous substance to do that. Especially when the testing has already been done during the development of gas lenses and it was proven that multiple fine screens align the molecules up far superior. I could prolly find an article again where I read about the use of these type of porous spongy filters being tried I know I have a link somewhere.

On a side note was wondering if you could use a spray on ceramic coating on inside to help insulate your copper cup so you could use the gas lens without making the cup live. If coating gets scratched bad enough won't do any good but it's an option. The ceramic coating I refer to is what we use on pistons. Takes heat very well and the ones I tested with a ohm meter did not carry continuity.

The porous media strives to serve a slightly different purpose, from what I've gathered. Fine mesh screens do provide laminar flow, but this in and itself does not necessarily provide better coverage---it serves to conserve gas flow or extend allowable tungsten stickout. Porous media can serve to disperse a given amount if gas flow for a larger cloud cover (works as if the cup size was actually larger) for sensitive reactive metals, not necessarily conserve gas flow rates.

[dirtmidget33]

Oscar porous material creates a turbulent flow the gas is bouncing everywhere. think of all the different directions a molecule will have to change its course by just going threw a quarter inch of scotchbrite. yes it is dispersing but at same time will never create a dense flow of argon like the screens do. The reason they call it a gas saver is the flow is so much more efficient by aligning the flow and compacting argon molecules closer together far better then any scotchbrite pad will ever do. You can run a little lower flow to achieve better coverage then you could by using the same size cup with a diffuser running at a higher flow. Hence they started referring to it as gas saver.

Here is a link will give you the orginal patent numbers for the lens. Union Carbide listed on patents . Gene Gorman originally tried a porous brass material but found screens far more efficient. The design was later improved by Cliff Hill. the CK designs are just jumbo versions of this design.

http://www.netwelding.com/history_tig_welding.htm

Gorman patent
http://www.google.com/patents/US3053968

Cliff hill patent
http://www.google.com/patents/US3180967

Invented in 60's and yet we argue about this today. What really irritates me is new designers make a flashy cup with an inferior porous junk (scotchbrite ) that tests from 50 years ago has already proven porous materials to not be as efficient as other methods available. If you want to improve on a design learn from what others have already done, tried and dismissed. Then the new age designers use a pad that is meant to clean and not take high heat. history does repeat itself we fail to learn from the elder generations

[dirtmidget33]

Superiorwelding, don't take my previous post as an insult or dig to what you are trying. I realize you are missing around duplicating some designs that others have made and charging high dollar far. Also the ceramic coating I spoke of isn't an anti splatter for welding. I should have been more detailed. It is a ceramic coating applied to pistons in racing motors Normally. The coating creates a thermal bearer to keep heat out of the piston. Some ceramics that is also used is to aide in lubrication and wear. Most of these are normally sprayed on then baked. Depending on the manufacturer some might conduct electricity Depending on the formula they use. I put a meter on piston I had laying around with coating to check if it had continuity and this particular coating didn't. This piston was bought coated so not sure of the particular ceramic coating.

[GreinTime]

Personally, I think that a ceramic cup with a Furick diffuser in it would be the cats meow if you didn't want the Pyrex nozzle kits.

[Superiorwelding]

Superiorwelding, don't take my previous post as an insult or dig to what you are trying. I realize you are missing around duplicating some designs that others have made and charging high dollar far. Also the ceramic coating I spoke of isn't an anti splatter for welding. I should have been more detailed. It is a ceramic coating applied to pistons in racing motors Normally. The coating creates a thermal bearer to keep heat out of the piston. Some ceramics that is also used is to aide in lubrication and wear. Most of these are normally sprayed on then baked. Depending on the manufacturer some might conduct electricity Depending on the formula they use. I put a meter on piston I had laying around with coating to check if it had continuity and this particular coating didn't. This piston was bought coated so not sure of the particular ceramic coating.

dirtmidget33,
I really appreciate you posting those links. I have read some of them before and it was good to read them again, especially while I am trying to play around. Although I am messing around this is quite fun. I have a few more ideas to try out as well as order some fine screen mesh material for fun.
As for the ceramic coating, I do know you were referring to a totally different ceramic coating but just thought of this anti spatter as a quick try. The coating you are referring to would work well I believe. I might start a thread soon or dig up someones exsisting thread about custom cups, I think it is of interest to a lot of us.

I did not take anything as a insult. I can be quite difficult to make mad. Although I have been known to hold things in longer than I should and just explode.
-Jonathan