[dmcnally]

Hi,
I'm a 55+ hobbiest. I took an intro to welding class at the local junior college. It was 16 weeks long and we spent the first half of the course learning oxy-fuel welding. In the second half of the course we learned stick (SMAW) welding. For a teaser we got one day (3 hours) to run a few beads using a MIG welder and one day to work with TIG.

I recently bought an AHP AlphaTIG 200X inverter welder and I've been learing how to TIG weld. I'm following the same method we used in school.
1) make a puddle.
2) move the puddle across a piece of mild steel.
3) run beads on top of base metal adding filler metal.
4) start making joints (lap, butt, tee, etc.)

Being that I have my own welding machine in the garage I'm not under the time crunches (i.e. graded projects) I was when I was taking the welding class. I can take my time and work on something until I think I'm ready to proceed to the next step. I'm pretty patient and I believe in building a good foundation before moving on to more advanced, or complicated, processes.

Sorry for the long intro, but I wanted to give a good background. I'm currently working on step 3 (running stringer beads on mild steel). I'm working on getting consistent beads with good penetration, stacked dimes, and color.

I'm currently running DC- @100amps max with a foot pedal, 17.5 CFH Argon, 7 seconds postflow, 3/32" E3 tungsten, #6 cup, 3/32" ER70S-2 filler rods, and 1/8" thick 1.5"x5" cold rolled steel work pieces (coupons). I've run 7 or 8 practice rods and my beads are getting much better, but my consistency still needs a lot of work.

One of the issues I have right now that I'd like to improve is the color, or finish, of my beads. The instructor (and YouTube videos) had nice beads. Mine have a gray covering, which is not what I expect. I have an angle grinder with a wire cup and I can clean up the beads, but I'd like to learn how to not get the gray stuff in the first place.

100_2339.JPG (48.46 KiB) Viewed 1852 times

100_2346.JPG (36.52 KiB) Viewed 1852 times

Comments, advice, and suggestions, are welcome and encouraged.

thanks,
Dave

[RamboBaby]

Well, if it piles up on top of the base metal and rolls over and under (like your finger sitting atop the work piece) that is called cold lap. It means that you are not pushing enough amperage. There can be many causes for this including adequate amperage while pushing too much rod into the puddle or traveling too fast. In your case I would venture that you have a couple of things going on here. Too little amperage and too much rod chilling the puddle.
Try this: crank your amperage up to 125 and push about half as much rod into the puddle. Basically you will be just dripping one drop of rod onto the end of the puddle rather than actually pushing the rod into the puddle. Trust me because this works very well for running practice beads where there is no joint involved. Once you start doing groove and fillet welds then you will need to go back to pushing the rod into the puddle but without a joint to fill.....you're feeding way too much rod.
Rule of thumb is 1 ampere per 1 thousand of metal thickness. This doesn't necessarily hold true when you're not joining two pieces of metal but after a few beads you will begin to see the results of too much amperage and that will tell you how far to back off of your peddle. It's always better to have too much amperage than too little.
If you put too much rod into the puddle and see it begin to pile up, give ig a quick blast from the peddle and watch the puddle wick out like butter melting in a hot pan.
Extra amperage on tap is always a good thing to have. Just don't get silly with it.

[Poland308]

Working on thin metal plate. 1/8 I think you said. Means that by the time you run about 2 inches of weld you have heated up the whole bar to the point it's getting that gray oxide layer on it. I agree you should crank up the amps a bit but only go up about 3-5 amps at a time. If you want to make longer practice beads and have them come out shiny then you will need to go to a bigger practice plate. Maby find a plate that's 1/2 inch or thicker. Jody had a video about stacking beads on a plate where he dunked it in waster to cool. It's fine to do this on a practice plate. Keeping it cool between passes will go a long way to giving you the shiny beads you want.

[RamboBaby]

A gas lense really helps a lot but if you're making any welds of significant length then it is going to oxidize unless you lay a ton of argon to it, through a large cup, use a trailing cup behind the weld and have a ton of post flow ( 20 to 25 seconds).

Try this: turn your argon up between 25 & 30 cu-ft/hr and run a 1" bead. That weld should come out loking like bright and shiny nickel but that much flow through a small cup is likely to make funny impressions into your weld bead. A little bit of oxidation is just the nature of the beast and it is acceptable in noncritical applications.

[dmcnally]

Thank you for taking the time to post a reply. I don't have any larger and thicker pieces of mild steel, but I'll try the other suggestions and see what happens.

thanks again and enjoy what's left of the long weekend.

[Oscar]

keep your arc length short and consistent. Too long of an arc will dump more unnecessary heat into the part, making ugly dull welds all but a certainty. Shoot for <1/16" arc length, and hold it consistently.

[Diesel]

You need to make lines with a grinder or sharpie to give yourself a guide. And it looks fairly cold. Put it at 150 and let yourself learn to control the puddle by feel not a number.You can control it with more than a foot pedal and a dial. Wire chills it, sometimes I use my wire as a buffer to do thin metal at higher amps. Arc length and angle will also give you more or less heat. I assume you have a foot pedal so that climates the need for these tricks.

[weldit321@gmail.com]

All of these suggestions are good. Using a gas lens is great, cooling the piece will help for practice (watch out for hardening carbon steels), and closer arc length would be my remedies. I would also however overlap your beads by about 50% to practice keeping a straight line, as well as amperage control to keep a consistent bead width. Another thing would be, dont be afraid to go slow and let it melt in with less heat just to get the feel for things. Looking good so far man.

[dmcnally]

I ran a few more practice beads last night and this afternoon. I upped the Argon to 25 CFH and I upped the Max amps to 125. I made a special effort the keep the electrode as close as I could and I dunked the work piece in water after each bead. Below is the practice coupon I did this afternoon. Note: the finish was a lot better than an few days ago, but I still cleaned it up with the wire cup on the angle grinder.

100_2363.JPG (65.27 KiB) Viewed 1730 times

100_2370.JPG (71.13 KiB) Viewed 1730 times

Thank you for the advice and suggestions.
Dave

[LtBadd]

I ran a few more practice beads last night and this afternoon. I upped the Argon to 25 CFH and I upped the Max amps to 125. I made a special effort the keep the electrode as close as I could and I dunked the work piece in water after each bead. Below is the practice coupon I did this afternoon. Note: the finish was a lot better than an few days ago, but I still cleaned it up with the wire cup on the angle grinder.

Thank you for the advice and suggestions.
Dave

Keep at it Dave, looks good

[RamboBaby]

Your beads still look cold but your ripple spacing is improving dramatically. Looks like you're starting to get a feel for the rythm.
Don't keep your argon up that high because there is no need in wasting it like that. That suggestion was just for test purposes. There's really no need to worry about your welds being gray because they will clean up just fine.
I rarely ever switch from a #7 cup with gas lense, 3/32 electrode (2% lanthanated) and 15 cu-ft/hour argon (really wish I had a tank of helium to add into the mix - for aluminum - but that's too rich for my blood at the moment). Jody mentioned that particular setup in one of his videos and it really works for almost everything that you will encounter.
Show us what your workshop looks like brother. I just added a bunch of the kit hanging on the wall a few days ago which is why a lot of it is still in the packaging. Here's mine:

[dmcnally]

Thanks. Here's my welding table. I inherited some dollar coin vending machine stands and I never threw them out. I screwed a base on both ends and that's my welding table. The bases are cast iron and won't catch on fire. On top of the base I have a 12"x12"x3/8" piece of steel plate that's my welding surface. This works fine, and is comfortable, for doing practice beads.

100_2387.JPG (47.1 KiB) Viewed 1401 times

100_2389.JPG (67.4 KiB) Viewed 1401 times

My welding cart is a Harbor Freight moving dolly.

100_2388.JPG (64.77 KiB) Viewed 1401 times

I move my car out of the garage and setup my little table when I want to use the welder. I'm in the process of getting rid of a few bikes (83 Honda CR480 and 92 Honda XR250) that I don't ride anymore. After the bikes are gone, and I have some room, I'll figure out a more permanent arrangement.

Dave

[RamboBaby]

Nice. My table is an old transmission build table that I covered with a sheet of 3/32" aluminum. The aluminum is about 50 times as conductive as steel so nothing ever even thinks about trying to weld to it.
I bought my welder specifically with the idea of being able to weld thick aluminum so the water cooler on the bottom of my welding cart was an invaluable addition.
I forgot to plug it into the welder one time when I move things around and fried the water cooled torch that came with the welder. Then i melted the "9 aircooled torch that came with it while I was waiting for my CK torch to arrive. I really should have bought a flex head or flexloc torch because when I stopped practicing and started building stuff I discovered why the aforementioned torches are made and sold. All in all I think that the rigid torch is making me a better and more versatile welder though. Still wishing that I had a flexloc regardless.
Do yourself the same favor and get a sheet of aluminum to cover your table.....youll be glad that you did.