jasonb

ok, so i'm not even going to mention this in the tech section. my track record isn't good on fabricating stuff.

that said, i'm going to give an honest effort to get more serious and i've gone and bought a TIG welder. Its a computerized inverter style with all kinds of controls for the waveform, really kickass stuff.

except i don't remember an effen thing on how to setup one of these things up for aluminum or stainless. so this morning i enrolled in a welding class at chabot cc. so every tuesday and thursday i'm going to parking my *** from 7-10pm, in a chair, welding.

its a few years old - a thermal arc 185tsw


the goal is to make a few easy parts for the car - brake duct backing plates, anything small and easy. and then as i get better - a manifold ala bob's manifold. i'll start with schedule 10 304 and work myself up to 321 stainless if i can do it. then i'll do downpipe and an open wastegate dump.

if i crash and burn, i'll sell it to one of u'all

fooger03

iTrader: (2)

Welding is the next big skill that I want to learn.

I think I'll start on a MIG though...

jasonb

yup. get yerself one of those little lincoln 110v migs. they work really well for mild steel as long as u dont get too thick. ive tried aluminum and stainless. not so good.

lets see how i do on the tig. my mig these days is medium shitty. turns out i have to lay a bead down every now and then to remember how.

sure glad my bbq island has a 60amp outlet

dustinb

Enjoy it. I wish I had the money, time, and will power to learn how to weld.

Rennkafer

iTrader: (3)

The class at Chabot is fairly good if you're reasonably self-starting... don't expect a lot of one on one attention. I took the class last winter and it's proven somewhat useful, I stick stuff together once in a while at work and once I get a place to plug my TIG into I'll be getting a bit more practice.

jasonb

anybody who finds themselves in union city with two pieces of metal they want to stick together is more than welcome to bring them over. the more exposure i get the better.

i need to make a place in the garage to plug mine in. right now i only gots power outside.

what machine do u have?

chicksdigmiatas

iTrader: (11)

Good drunk buy. Last drunk buys I had were p90x and a beer boot.

ARTech

iTrader: (34)

That's the same welder I use. Awesome machine for the price.

Do you have a dryer plug in or close to your garage? You can make a 25' extension for about $40-50USD in hardware store parts. Even if you end up hardwiring your garage for 220v, an extension comes in handy if you ever need to work outside of your house, at a friends, etc.

jasonb

u also have? cool. i wasn't expecting one o y'all to have. got any pics of a manifold so i know what i'm shootn for?

i got a 30amp dryer outlet, currently being used by the air compressor, although no problem to switch back and forth. i'm very lucky all it needs is a 30amp. house itself only has a 200amp service and its a little bit pita to get permits to run big subpanels.

vw_nut

iTrader: (1)

Great welder for the $$! I have one and like it alot. The interface takes a little getting used to, but works great once you have it set up.

I need to get a thumb controller for mine as I am not the most coordinated person and working on car projects with the foot pedal can be a pain at times.

curly

iTrader: (25)

Huh. If only there was a picture of exactly what you are looking for directly under his screen name.

jasonb

u have a point (wear a hat so nobody will notice). 'cept i like my car pr0n more than 150x94 pixels. lay some 4mpixel pics on me then u talkin

jasonb

first day @ chabot welding lab. this stuff takes a fine touch boy howdy. tried out aluminum first. the middle one is my best - little bit shiny which is good. the others are dull which means i got it too hot.

now i need to plug in the thermal arc and see if i can do it with that one. thursday i'm gonna try stainless and see what thats like. good times.

jasonb

i was thinking about the thumb controller thing (even watched some youtube on a rotary thumb controller). i'm not sure i'm coordinated enough to work a thumb controller. i guess its sort of like using an air brush?

jasonb

crikey, mad props to u (and the other folks) who can do nice welds.

this **** is really hard for me. 2 months and this is my best:

Rennkafer

iTrader: (3)

Sorry for the late reply, this is the TIG I have... Miller Synchrowave 300. It's huge and old school but will do anything I'll ever need (and it only cost me $650 with a brand new water cooled torch). I just need to figure out a way to get it out of the truck when I bring it over to my house from storage, it's about 1100lbs. Wonder if one of my neighbors is hiding a forklift...

SKMetalworks

iTrader: (7)

Try to get in a rhythm and make sure your tungsten is sharp as ****. Also, try to get enough angle so your rod don't melt before you get to your puddle. Basically, act like a machine.

jasonb

nice machine. i was looking for one of those on craigslist for a while. and now i'm glad i never found one - 1100lbs!? the copper alone in that thing must be worth $650.

I have a harbor freight 700lb capacity dolly and a trailer. if you want to give it a go just holler. it might be worth the $50 bucks and rent a pickup with a lift gate from centerville rents tho.

i know what you mean about the rhythm thing. i've done it couple of times and it almost seemed easy. then i'll struggle for another couple of weeks before it happens again

i hope that the learning curve flattens out soon. its like cooking temperature is everything. and don't get your tungsten too close or it sticks (as in my pic). don't touch your filler to the tungsten or everything turns green and u can't see ****. when i look at some of the work done by the vendors here i'm amazed a whole manifold/exhaust can look that perfect.

they should go on walls not under cars.

Joe Perez

iTrader: (8)

Also late to the party...

I've been eyeing TIG machines on and off. If I may ask, what led you to choose the Thermal Arc over a more common brand such as a Miller Diversion 180, which is about the same price?

jasonb

my criteria was completely unscientific - it was used, but it was posted on a forum by somebody i trusted. it had very few hours on it and the specs looked like it would do all the stainless and aluminum work i would likely want to try.

your right tho about the service part, i was a bit concerned it would be hard to get serviced, but i read weldingweb etc and folks said it is a pretty reliable unit, so i pulled the trigger. in a strange sequence of events, it happened that a friend of mine flew up to portland and rented a truck to bring some stuff down the same week that i decided to buy this thing. this is good because you cant ship gas bottles unless empty.

i have limited experience but i'll offer what i've gathered on the various tig machines

stainless:

most of the stainless work i've done is with 14/16 gauge or so and you don't need much current. for the thicker stuff, maybe start at 75amps and then back down into the 60's when you got your puddle going. for thinner, i'm down in the 30's or 40's.

schedule 40 pipe for a manifold might need some more serious amps. i'll have to grab some and give it a try. i shouldn't think it would be much over a 100 though. (somebody correct me if i'm way off).

waveform: its just DC with a high frequency start for the arc, so all machines will be quite similar.

executive summary: all of the "hobby class" tig machines should be fine i think.


aluminum:

aluminum takes current. even relatively thin aluminum takes alot of current compared to steel, i don't recall ever going under 125A to start a puddle. you also use AC current with aluminum so you are "splitting" your current which also makes your machine work harder. by splitting i mean some of the current is spent putting heat into your weld puddle (electrons flowing from tungsten to metal), and some is spent in "cleaning" the metal (electrons flowing from metal to tungsten). you can see this in the first pic of the aluminum welds. that satin finish around the edges of the weld is the "cleaning" effect. (you want this because aluminum oxide is really hard to weld, and the cleaning effect is burning that layer of aluminum oxide off for you).

this is a long winded way of saying when you decide on what machine to get, do it based on your aluminum usage.

looking at the thermal arc duty cycles:
100A - 100%
130A - 60%
160A - 40%
185A - 30%

diversion 180 duty cycle:
60A - 100%
150A - 20%
180A - 10%

miller lists 3/16" as max aluminum, but it looks to me that its not going to be very happy spending much time above 150 amp.

waveform:

looks to me there are two different aspects to the waveform that you care about for aluminum (at least for inverter tigs). how much of the AC cycle is spent cleaning vs putting heat into your puddle, and how fast it alternates.

some machines will have a fixed 70%/30% split for the waveform which you can't change. this might be ok if you always work with the same material, but when purchasing, i would like a machine you can change that depending on how clean your metal is.

the transformer based machines have a fixed 60hz cycle time so no choice. the inverter machines have ability to vary this. i think it is kind of a neat feature because it changes the nature of the arc depending if you want shallow penetration or deeper penetration. i've read anything above 150hz is diminishing returns.

thats about the extent of my knowledge. the thermal arc also has pulser settings which is cool in theory. it would help limit the amount of heat you are putting into the metal etc, except that i've been told it is really tricky to get the timing right for adding filler. i'm not going to play with that until i can reliably do it the old fashioned way.