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View Full Version : Teaching myself to weld... Cleanliness?



cggorman
03-23-2016, 11:59 AM
Hey all! I'm an industrial brazer by trade (among other things) and cleanliness is quite critical for proper alloy adhesion and flow. To the point that I must be careful of what abrasives I use...

How careful do I need to be with cleanliness while MIG welding mild steel? If the sheet comes from the mill "clean" (no surface rust) and I wipe it off with alcohol is it clean enough? Any concern with aluminum oxide abrasives? What about finger prints and non-visible oxidation that is hard to reach in inside corners after I bend up, say, a 5 sided box?

Thanks! I'm hoping to strike my first arc tonight.

billybiltit
03-23-2016, 2:28 PM
the cleaner the better.
but,
mig is pretty forgiving when it comes to dirtyness.

i have mig welded through paint and dirt,it doesn't penetrate as well and is more apt to cold lap and smells horrible.

keep everything clean an inch either side of the weld and you will have no problems.

leon

cggorman
03-23-2016, 4:14 PM
Thanks! Is mineral spirits an acceptable cleaner?

Keeleyvision
03-23-2016, 4:52 PM
Thanks! Is mineral spirits an acceptable cleaner?

you don't even need to go that far

farmall
03-23-2016, 5:08 PM
You can't get too clean though welding is very tolerant. A flap disc is plenty sufficient in most cases.

Since you braze you know puddle control and you ain't skeered of a torch. You might REALLY like oxy-acetylene welding and it's insanely versatile.

Some evening fap material: https://www.tinmantech.com/gallery-of-metalwork/

Flabadabadingdong
03-24-2016, 8:02 PM
Cleaner is better but if you're just working with mild steel you don't have to go crazy. Just knock that mill scale off and you're fine.

ReRunCycleWorks
03-25-2016, 9:56 AM
for most occasions i use 3 levels of prep for MIG if its "clean" metal ill just swipe it real quick with brake cleaner (mostly cuz i always have it on hand), if its a little "dirty" wire brush/ brake cleaner, or if it needs some good attention a flap disc/ brake cleaner. but like its been stated MIG is super forgiving it really has to be roached to be unmanageable depending on the thickness of material.

matttatts
03-26-2016, 12:47 PM
for most occasions i use 3 levels of prep for MIG if its "clean" metal ill just swipe it real quick with brake cleaner (mostly cuz i always have it on hand), if its a little "dirty" wire brush/ brake cleaner, or if it needs some good attention a flap disc/ brake cleaner. but like its been stated MIG is super forgiving it really has to be roached to be unmanageable depending on the thickness of material.

You Wana be real careful with break cleaner around something you are going to weld. If you have a tiny puddle of break cleaner and you end up burning it and inhaling it poison as fuck. Serious bidness mayn.

farmall
03-26-2016, 7:10 PM
Yep, ensure no remaining brake cleaner if welding. Phosgene was a popular WWI war gas...

http://www.brewracingframes.com/safety-alert-brake-cleaner--phosgene-gas.html

Acetone is an old standard for precleaning weldments. It is a relatively safe cleaner (the human body produces a small amount) that is so effective it is "oxygen safe" meaning you can clean equipment such as welding regulator parts which are exposed to high pressure oxygen with it. (Obviously parts must be COMPLETELY dry before contact with high pressure oxygen.)

cggorman
03-27-2016, 7:39 AM
Thanks for all the tips! I always have acetone and mineral spirits on hand.

I don't have a torch at home but I'd heard that warpage was a major problem with torch welding.

I got a used MIG setup at auction but the shield gas cylinder is empty. I'll have to wait for payday to have it tested and filled.

Dragstews
03-27-2016, 11:49 AM
https://s-media-cache-ak0.pinimg.com/236x/1d/5a/6d/1d5a6dc08fd76085a6b7f33b58a0178a.jpg

some1else
03-27-2016, 1:08 PM
close the lids and put the rag away from any arc sparks be safe and good luck

Flabadabadingdong
04-01-2016, 5:03 PM
Thanks for all the tips! I always have acetone and mineral spirits on hand.

I don't have a torch at home but I'd heard that warpage was a major problem with torch welding.

I got a used MIG setup at auction but the shield gas cylinder is empty. I'll have to wait for payday to have it tested and filled.

Just a heads up, most places won't refill your cylinder if you bring one in. They generally make you rent one of theirs.

cggorman
04-01-2016, 5:29 PM
My local supplier is independent and doesn't care. I've been going to them with my CO2 (for fish tanks) for years. I took my empty to them on Tues to have it filled with C25 but the cylinder isn't rated for 2K PSI so I had to wait til yesterday to get paid so I could buy the right tank. Bought a new 144 cuft tank filled for $250. I'll have to get it recertified every 10 years but I prefer to own instead of rent.

Haven't had an opportunity to get it hooked up yet. Maybe tomorrow.

cggorman
04-01-2016, 5:36 PM
I did spark my first arc early in the week but it was with the old slightly oxidized .030 wire that was in the machine and some straight CO2 I had laying around with an improper regulator I stole from one of my fish tanks. Welding corners on a 20 gauge box I bent up. I wasn't real happy with the results so I picked up some .023 wire and the right tank/gas to fit the regulator/flow meter that's meant for welding. Hopefully that helps. Certainly can't hurt!

ReRunCycleWorks
04-01-2016, 5:47 PM
You Wana be real careful with break cleaner around something you are going to weld. If you have a tiny puddle of break cleaner and you end up burning it and inhaling it poison as fuck. Serious bidness mayn.

No worries I always wipe it down with NO! residual cleaner... Heard way to many horror stories

xMPRx
04-01-2016, 9:18 PM
You Wana be real careful with break cleaner around something you are going to weld. If you have a tiny puddle of break cleaner and you end up burning it and inhaling it poison as fuck. Serious bidness mayn.

using the NON Chlorinated break clean is just fine to weld with. Not ideal, but like farmall aid acetone is still the standard in alot of high end fab shops.

farmall
04-02-2016, 1:06 PM
Since OP has a good indy gas source (many peeps do not) I suggest constantly lurking Craigslist for more cylinders. You can never have too many or too much variety.

Helium and nitrogen cylinders have the same CGA 580 valve as argon and mixed MIG gas so you are highly likely to be able to exchange them.

Most places will take forever to refill a customer cylinder the first time, but after they hydro (if needed) and refill it then it's normal to be able to exchange those for full ones. I've had cylinders vanish for months then come back to me (my LWS doesn't fill or hydro onsite) but I get them so cheap I can wait and by not snivelling I become the "good" customer.

Owning beats the fuck out of renting because time passes quickly and rental fees add up.

Since OP already has CO2 cylinders for fish tank use, he could pick up another regulator (or use one he owns if it will do high output pressures) and hang a brass air chuck on it to use them as portable "power tanks". Having a couple hundred PSI for your impact wrench is damn useful.

I suggest hunting a mixed gas cylinder for welding though CO2 does work. Your existing welding regulator can be used with an adapter unless it is already a CGA 580 and comes with a common "CO2" CGA 320 adapter.

If your reg has a CO2 male nipple, this (example) http://www.amazon.com/Western-Enterprises-Brass-Cylinder-Adaptors/dp/B0029YB0LS will connect it to a "MIG gas" cylinder valve:

http://www.amazon.com/Western-Enterprises-Brass-Cylinder-Adaptors/dp/B0029YB0LS

For those with a typical CGA 580 regulator you can adapt to CO2 using:

http://www.amazon.com/Western-Carbon-Dioxide-Adapter-Nitrogen/dp/B0024LIUDM

Your local welding supply may stock these.

BTW if your .023 wire birdnests excessively take care to keep your gun cable straight. You'll like it for sheet metal.

Flabadabadingdong
04-02-2016, 4:24 PM
Pictures of your welds will help us give you advice on your technique and such too.

cggorman
04-02-2016, 4:40 PM
That's very generous. Thanks! Once I get back to that end of the shop and get the new stuff installed I'll post back.

cggorman
04-11-2016, 6:31 AM
I feel like I'm doing OK. Not cosmetic yet but I've got some heavier stuff to weld later on. This is only 20ga. I cut it, bent it, welded all four corners, formed the screens and spot welded them in. Not too bad for my first attempt I think. I burned thru in a couple places but got the holes filled in OK. My welder is old and only has 6 heat settings. I feel like I need something between "1" and "2"... Sorry, I didn't get pics of the welds before I ground them.

http://i26.photobucket.com/albums/c130/cggorman/Harley/IMG_20160408_220143_zpsnifzz7de.jpg (http://s26.photobucket.com/user/cggorman/media/Harley/IMG_20160408_220143_zpsnifzz7de.jpg.html)

http://i26.photobucket.com/albums/c130/cggorman/Harley/IMG_20160409_234731_zpsfhti2qev.jpg (http://s26.photobucket.com/user/cggorman/media/Harley/IMG_20160409_234731_zpsfhti2qev.jpg.html)

http://i26.photobucket.com/albums/c130/cggorman/Harley/IMG_20160409_234751_zps8dxw2tja.jpg (http://s26.photobucket.com/user/cggorman/media/Harley/IMG_20160409_234751_zps8dxw2tja.jpg.html)

http://i26.photobucket.com/albums/c130/cggorman/Harley/IMG_20160409_234816_zps5qtwrlm8.jpg (http://s26.photobucket.com/user/cggorman/media/Harley/IMG_20160409_234816_zps5qtwrlm8.jpg.html)

http://i26.photobucket.com/albums/c130/cggorman/Harley/IMG_20160409_234706_zps1adrvukk.jpg (http://s26.photobucket.com/user/cggorman/media/Harley/IMG_20160409_234706_zps1adrvukk.jpg.html)

cggorman
04-11-2016, 6:36 AM
I also need to get a better helmet. Mine is probably from the 60s and the glass in mine is too dark and I get really bad reflections inside from the ceiling lights if I'm looking down at all.

Are the auto-dimming ones from HF a waste of money?

Keeleyvision
04-11-2016, 7:03 AM
I also need to get a better helmet. Mine is probably from the 60s and the glass in mine is too dark and I get really bad reflections inside from the ceiling lights if I'm looking down at all.

Are the auto-dimming ones from HF a waste of money?

Don't get a HF auto shade, if you are going to buy an auto shade buy a good one, don't play with eye protection. I have been a welder for over half my life, I have yet to find an auto-shade I liked, If you are having visability problems get a Lincon super visability 10 shade, it's a great lens that won't slow cook your eyes.

cggorman
04-11-2016, 7:30 AM
Thanks. Good to know. I may run out to the welder supply next payday and try some helmets. Is it possible to get something decent for less than $150? I hate fighting with cheap tools/equipment, but I'm not a pro wrench so I try to find good value too.

Ironman68
04-11-2016, 9:23 AM
They also make flux core wire that you don't need gas for,works good if your welding outside or in an area that you can't control the wind/air flow,gas will blow away easily,some shop mig welders do what's called duel shield which is flux core and gas combined,it gives a lot purer weld and works good with mild steel also I have never had a need for any chemicals on mild steel usually just hit it with a small grinder with a sanding disc on it,aluminum on the other hand is a very different story and it has to be very clean and it is better to use the tig process for heat control/concentration with aluminum

StinkyPete
04-11-2016, 10:00 AM
Looks good - no warpage that's usually a side effect, unless you did some straightening with your finishing.

I'm not sure about your prep, but making sure your edges are clean (filed) and not ragged will help with blow out as the ragged edges can hold oxygen that will flare. You probably already know that from brazing, but thought I'd share.

cggorman
04-11-2016, 10:05 AM
Nope, no warpage. I took small bites. Maybe 3/4" at a time. The edges were sanded on a belt sander.

I've read that flux core burns too hot for sheet metal, so I didn't even try it.

Had a little trouble tacking in the screen at the corners. The arc kept wanting to jump to the side wall.

Keeleyvision
04-11-2016, 1:50 PM
Thanks. Good to know. I may run out to the welder supply next payday and try some helmets. Is it possible to get something decent for less than $150? I hate fighting with cheap tools/equipment, but I'm not a pro wrench so I try to find good value too.

Yes they do, look for a hood called "huntsman" it's not pretty, nor flashy, but it's a great, inexpensive hood, with a slide lever on top that pulls the shade up and out of the way of the clear lens so you can use it as a shield for grinding
https://weldingsupply.com/cgi-bin/einstein.pl?PNUM::1:UNDEF:X:14534

cggorman
04-11-2016, 2:13 PM
Default
Wow, $33! I haven't yet seen a hood that cheap around here, but these all seem to be pretty flashy. Graphics, auto-tint, sculpted shapes, etc. I just need something I can beat up. Thanks for the tip!

StinkyPete
04-11-2016, 2:17 PM
I've read that flux core burns too hot for sheet metal, so I didn't even try it.

Yep - you should aim for .023 wire. I believe flux core is .03 / .035, which is pretty heavy for thin sheet.

Flabadabadingdong
04-11-2016, 2:30 PM
Thanks. Good to know. I may run out to the welder supply next payday and try some helmets. Is it possible to get something decent for less than $150? I hate fighting with cheap tools/equipment, but I'm not a pro wrench so I try to find good value too.

It's at the top of your budget but this is the hood I've been using for the past year until I got my Speedglass. I don't have any complaints about it.

http://www.bakersgas.com/LINK3023-2.html?gclid=CjwKEAjwlq24BRDMjdK7g8mD6BASJABBl8n3I 74x49moeSjIoFpvupZroWqbsXpP2Cw8aRgLZMptzBoCrW_w_wc B

cggorman
04-11-2016, 2:44 PM
Yep - you should aim for .023 wire. I believe flux core is .03 / .035, which is pretty heavy for thin sheet.

.023 silicon bronze is the wire I bought for this box. It's the only .023 we had locally. .030 was in the machine when I bought it. It didn't work for shit on this 20ga, but its old and discolored and I was using straight CO2.

olddog1
04-12-2016, 11:40 AM
I too have been welding most of my life "cpw-33yrs", and what was said about a Lincoln #10 SuperSensitivity is very good. Or a NextGen hood- or Speedglass & such. Just so you know if ever you wish to weld Alum.-Mild steel, you can buy Aluma-Weld(been around for acouple yrs.) wire(tig). Not that cheap, but reasonable. Mig welding is agood and forgiving process, But TIG is where it's at. Just saying. GoodLuck and enjoy it (slow n steady

cggorman
04-12-2016, 12:25 PM
Eventually I'll get a TIG machine and plasma cutter, but the upfront expense is keeping out of that game for now.

Have 20 years oxy/fuel torch brazing experience with both ferrous and non ferrous. MIG makes me miss the control and precision. TIG should bring some of that back.

StinkyPete
04-12-2016, 1:21 PM
Have 20 years oxy/fuel torch brazing experience with both ferrous and non ferrous. MIG makes me miss the control and precision. TIG should bring some of that back.

This may be a dumb question - what's keeping you from just gas welding this? Note - I have not gas welded yet, but plan to try it soon as a coordination-builder / practice before jumping up to a TIG machine.

Switching to TIG vs. gas welding - I know it's not exactly the same (burn a pool vs. arc a pool), but the filler application is the same. Controlling an OA torch is nowhere near what a TIG pedal & torch provide, but doesn't gas weld allow better heat control than MIG?

Not hijacking, just curious now.

cggorman
04-12-2016, 1:48 PM
I don't have a torch at home. I'm an industrial brazer, so my equipment is at work. (Actually I'm a "prototype technician" so my job actually requires me taking a product from concept thru to delivery...so I can do CAD, basic machining, cost/price, tube bending, tooling, etc.)

I always assumed torch welding would introduce way too much heat into the base metal to make it useful for sheet metal. I suppose if I got a jeweler's torch... I mostly do larger stuff at work. My minimum base metal thickness at work is around .035 copper lap joint (so .070 total). Brass and steel are closer to .125 or more. On some of my large parts, I've used dual rosebuds or quad nozzles. The rep from Smiths that I talk to said she'd never heard of anybody using dual rosebuds and couldn't help with regulator or flow settings. Lol.

Anyway, I always wanted to learn to weld. One of the few fab skills I was lacking. MIG seemed cheap and versatile. Buying a complete torch outfit (tanks and all) would probably cost near as much as a cheap TIG box. Buying a used outfit would obviously be cheaper but the tank cert code and/or test would be a potential issue. I know Acetylene tank specs changed several years ago and old tanks were supposed to be replaced.


I'm running on...sorry.

cggorman
04-12-2016, 2:15 PM
Oh. Based on my very limited arc welding experience, Yes, a flame and filler rod offers much better control than MIG. Flame is also slower and requires much closer joint fit for the filler alloys I'm familiar with. Mostly silver blends. I've never done bronze/copper fillers.

JWright
04-12-2016, 5:02 PM
My local supplier is independent and doesn't care. I've been going to them with my CO2 (for fish tanks) for years. I took my empty to them on Tues to have it filled with C25 but the cylinder isn't rated for 2K PSI so I had to wait til yesterday to get paid so I could buy the right tank. Bought a new 144 cuft tank filled for $250. I'll have to get it recertified every 10 years but I prefer to own instead of rent.

Haven't had an opportunity to get it hooked up yet. Maybe tomorrow.

Most of the time they dont fill "your" tank. They just swap it with another full one the same size so as long as a bottle dosent expire while you have it you dont need to worry. I go through a bottle every few months and the closest to expiring that they have every given me was 2 years away

JWright
04-12-2016, 5:10 PM
I have the miller digital performance auto for work and have been using it for over 5 years, just had to replace the battery for the first time the other day. I have one of the lincoln auto darks from hd that I use at home. Its not as good or as comfortable as my miller but still no problems with it

cggorman
04-12-2016, 6:41 PM
My place fills my own personal tanks. They only exchange if I have a rent/maintenance agreement on file with them. You stand there in the shop and watch them fill them. They track tank serial numbers on the rentals and register the serials on owner tanks. Not sure how other places do it. This is the only place I've ever used.

cggorman
04-12-2016, 6:43 PM
Seems like we have split opinions on the auto darkening lenses. I'll have to see if Nowak will let me try/return. I'm honestly not at all concerned about comfort as long as it isn't painful. I'll probably never wear it for more than hour at a time at home. I just use flip-up glasses at work. I tried those. They're not dark enough for welding.

boomboomthump
04-12-2016, 7:51 PM
I'm also in the auto darkening club and would never use one w/o it. Been using one for several years and never had a single problem with it (Miller). Will never switch back.

seaking
04-13-2016, 6:16 AM
This may be a dumb question - what's keeping you from just gas welding this? Note - I have not gas welded yet, but plan to try it soon as a coordination-builder / practice before jumping up to a TIG machine.

Switching to TIG vs. gas welding - I know it's not exactly the same (burn a pool vs. arc a pool), but the filler application is the same. Controlling an OA torch is nowhere near what a TIG pedal & torch provide, but doesn't gas weld allow better heat control than MIG?

Not hijacking, just curious now.


Definitely not a stupid question. Gas welding--tack, then hand planish, finish weld, planish, then sand out the high spots. TIG centralizes heat and makes the parent metal brittle. MIG--planishing raises the weld, you sand to correct it and thin out the parent metal. No jewelers torch necessary.

JWright
04-13-2016, 9:55 PM
If you plan on ever going to tig than I would definitely suggest the auto dark for sure as its alot easier and you can also adjust the darkening. Hobart has a decent auto dark for under 150

cggorman
04-14-2016, 6:35 AM
If you plan on ever going to tig than I would definitely suggest the auto dark for sure as its alot easier and you can also adjust the darkening. Hobart has a decent auto dark for under 150


I absolutely plan on moving to TIG within the next year or two...finances depending...

cggorman
04-29-2016, 3:23 PM
Found a good deal on a discontinued Lincoln 2450 helmet. Gonna spend some quality time with it this weekend.

http://i26.photobucket.com/albums/c130/cggorman/Harley/IMG_20160429_171657_zpso1t3ixlr.jpg (http://s26.photobucket.com/user/cggorman/media/Harley/IMG_20160429_171657_zpso1t3ixlr.jpg.html)

farmall
05-01-2016, 5:00 PM
Don't forget to hunt deals on replacement outer lenses online before you need them.

ReRunCycleWorks
05-01-2016, 5:05 PM
I've had a few different lids around the shop over the years but to be honest I've been using a Tractor Supply special for the last year and i haven't had one issue with it.

cggorman
05-02-2016, 9:37 AM
It came with 6 outside and 4 inside shields. No more than I weld, that should hold me over forever.

This is the previous generation glass with the green tint. I went in looking to get the new one with the "4C" glass but this one was half off. I'm used to the green from work anyway, so no biggie.

Apparently the lights in my shop are really bright because even with only half of them turned on the glass went into welding mode even at the lowest sensitivity. I put a couple pieces of masking tape over each of the sensors and that helped but looked stupid. I had some adhesive vinyl tint film (smoke color, around 50% VLT it looks like, I can't remember) left over from a previous project so I tried that. One piece each worked a treat. Can't hardly see the tint and it lets me set the sensitivity near the middle and still function properly.

Life hack.

Keeleyvision
05-02-2016, 5:21 PM
It came with 6 outside and 4 inside shields. No more than I weld, that should hold me over forever.

This is the previous generation glass with the green tint. I went in looking to get the new one with the "4C" glass but this one was half off. I'm used to the green from work anyway, so no biggie.

Apparently the lights in my shop are really bright because even with only half of them turned on the glass went into welding mode even at the lowest sensitivity. I put a couple pieces of masking tape over each of the sensors and that helped but looked stupid. I had some adhesive vinyl tint film (smoke color, around 50% VLT it looks like, I can't remember) left over from a previous project so I tried that. One piece each worked a treat. Can't hardly see the tint and it lets me set the sensitivity near the middle and still function properly.

Life hack.

thats the downside to autoshades, anyone else in the shop strikes an arc, or uses a grinder, and poof, lights out.

cggorman
05-02-2016, 6:35 PM
The sensors are extremely directional but regardless I'll always be working alone so it shouldn't be a problem for me.