Ask your WELDING questions here.

1 1/4" aluminum tube that was cut too short. Problem is, it was attached to a very expensive piece. How difficult would it be to weld the piece back onto the end of the aluminum tube? Wall thickness???? 1/8" or so. Oh, and the bead can't protrude out the outside of the tube.

it's not that hard. just have someone bevel and weld around. they'll need to grind or file the weld off afterwards. is a hand ground/filed surface acceptable or does it need to have an accurate od? also, the aluminum where is was originally welded and around the new spot will likely be as strong as butter (~15 ksi yield) without heat treatment. that depends on the alloy.

if it needs a clean OD, i would just cut the weld off of the expensive piece, and weld the correct tube onto it. its about the same amount of work either way. what is the expensive piece? casting, machined part?

ok, so this is not one of those ground breaking questions, but still I would like to know the best paint match for the Lincoln Red. I picked up a Ranger 8 recently. Unit runs great and only has moderate hours on it. So since I plan on owning this thing for the 10-15 years, just thought I would clean it up a bit with a new coat of paint.

Thanks for the help

I've got some old school questions concerning a TIG torch use on a really old welder.

I inherited from my Pop an old Wilson 220 volt ingle phase, 200 amp BumbleBee welder from the mid 1950's The welder is AC, but is outputted through an even older AO Smith AC to DC selenium plate converter, that can handle 250 amps. This converter has the ability to switch between AC and DC+ and DC- with a big lever.

My welding background includes 2 years as a bicycle frame manufacturer employee. I was mostly doing tubing prep and mitering, but we were encouraged to learn other workstation skills and that included some MIG, TIG welding and brazing. I got fair marks for my TIG abilities, I didn't do production work, but got good at in-house repairs and Jig fabricating. So I probably know enough skills to get myself in trouble.

Can I get by with this old welder, which BTW doesn't have the high frequencey start so I'll have to "scratch" to get the arc started. My father a few years back bought a regulator and torch W/ leads and piping for the inert gas for this very welder but never really used it much. The torch itself has a manual off valve.

I realize this is really old tech but I'm intereted in doing some TIG work with this machine if it's possible?

Question from a welding Noob:

I have one of those 120V "buzz boxes" (Firepower FP130) and am teaching myself to weld by experimenting on scrap pieces. I have the welder set-up to weld without gas (.030 flux core wire).

I know that if you use too much electricity (voltage), you can burn thru the material. But, how do you set up the welder to weld two pieces of dissimilar thickness? For instance, I have a rear fender support that's made of .062 (1/16") tubing. I want to weld a pre-fabricated rack to the support. The rack has .1875 (3/16") plates that will be welded to the tubing. So, do I set up the welder as if I were welding .062 tubing? If so, is that hot enough to get good penetration on the thicker material?

I hope that makes sense.

TIA, Dave.

For the different thickness pieces, you can often go with the voltage set for the thicker material and adjust the wire speed/current on some pracitce pieces. The trick is to aim the wire and the arc to penetrate more into the thick piece and not burn thru the thin piece. That's the art of the process, and takes practice to place the heat more into one side yet still fill the joint with penetration of both parts. Learning to lay an uneven weave heavier to one side is one way to manage it. Keeping travel speed up will help avoid burnthroughs as well.

Depending on the range of wire speed/current settings of your machine, you'll want to dial it in to where as you maintain about 1/2" stickout of wire, the arc sounds like bacon sizzling smoothly and evenly. If the wire tries to burn back into the tip or ends very time with a big ball on the end of the wire, add more wire speed/current.

As I was teaching myself a few years ago on my trusty Handler 120, I found that once I picked a decent voltage setting, I could weld better by ear than by watching - doing little beads with a gloved hand over it and listeing to what the arc was doing. I still tack like that, doing it by sound.

scratch starting is a pretty frustrating ordeal, especially if you are relatively new to welding. does it have any type of remote control like a foot pedal or a hand control? you can find old high frequency starter boxes on ebay, or craigslist sometimes. i have one, and will probably be selling it once i get a chance to round up all the cables for it.

as for steel, it may do well on DC. if it as no external control it can be frustrating to start and stop welds. thin stuff requires more skill on your part since you can't back off the heat if you start burning through.

on ac without high frequency, you can't do aluminum. the arc will die each time the voltage crosses zero.

since you just need a bottle, tungstens and some filler and if it all works, it can be a great learning tool for teaching youself tig. start with 1/8" and up steel to get used to it. things mch thinner may be too frustrating.
if you really like the machine, you can grab a HF starter and use it. if not, you can someday lavish yourself with a modern machine. all of the things this machine is missing will be icing on the cake. make sure you clamp your work down, scratch starting can easily turn into spot welding.

i bought a broken linde C300 ac/dc tig (from 1960) on ebay for cheap and fixed it about 6 years ago. it welded steel as well as anything modern. aluminum took more skill to get clean welds, but were very possible. enough of it finally died that i gave up keeping it going, but it was a great machine until then. it did have a foot pedal and hf. and i did learn on a more modern machine. old stuff isn't bad. either way, you have what sounds like a nice stick welder.

keep in mind transformer machines draw way more power than the new inverters for the same output. my linde made the electric meter audibly spool up when i did aluminum. if you're just doing steel under 3/16" you can get something like a maxstar 150.

good luck
Mike

I will find out what the paint code is. It was powder coated red at the factory.

Thanks Mike for the response,

I'm already using the machine for small weld jobs around our place, I'm fairly good at stick welding, and yes it's a good welder for vanilla purpose, 6011 "1/8th and "3/16th welding. I've already fabricated a removable wood splitter for my old I-H crawler, that runs off an additional hydraulic control.

My main concern was if the "scratch" striking method was too damaging for the tungsten tip. I've already learned about regrinding and shaping these at my previous job. The torch has a primitive plexi gauge with a small ball bearing for flow metering. FWIW...

Thanks Mark. Obviously, I have some practicing to do.

Also Bronco - as soon as you even start to get fed up with the smoke and spatter of using flux core wire, change the machine over (if possible) or trade for a machine to run solid wire with inert gas.

It didn't take me long to reach that point (about halfway thru building a cart for the machine, which is a standard learning drill for folks teaching themselves). After switching to solid wire and C25 (25% CO2 and 75% Argon), no more smoke or spatter and no more knocking slag off before continuing. Straight CO2 will make for a hotter arc and slightly better penetration in steel, but the C25 mix leaves a prettier weld and I can switch over and run 308 SS wire without changing the gas and only suffer a little oxidation to clean up on stainless.

The machine will run gas now. I just need to find a local place that sells the small bottles (or do you buy the gas and 'rent' the bottle?). I have solid wire. So, the switch over will be no big deal. I just need some scap to practice on. Thanks again Mark - Dave.

I've got a noob welding question ... if I try to weld to the underside of the GS gas tank will it destroy the paint on the top of the tank? I had an enlargement welded to the underside of my R1100S aluminum tank and I'd like to try to enlarge the GS's tank.

While we're talking fuel tanks ... I'm hoping to cut-and-shut an old crumpled XLV750R fuel tank to bring the capacity up to 30L or so ...

Anyone know what gauge steel the tank's likely to be made of, and if it'll be possible to weld it up with my little MIG (SIP 150, goes down to ~25A with 0.6mm wire) without blowing holes in it?

Any other tips on welding fuel tanks (other than washing it out *REAL* carefully first!)

-----sharks

PS: Yep, Bronco, the small disposable cylinders are a waste of money, hire ye a cylinder ...

my old honda v65 tank was made of something about 24 gage (~.58mm), i.e. really thin stuff. first, clean the old paint off of the outside of the tank, open it up and air out. maybe put some gravel and dish detergent to scrub out the fuel residue then rinse. if most of the tank is open, like you would do to splice in extensions, fire hazard is possible, by explosion is unlikely because the pressure isn't contained. it's hard to recommend to people what makes them safe. i was trying to explain to a friend accross country how to make a boat tank safe to ship and got many good responses here.

the best way to mig weld would be to lap joint the new metal in, have the new metal lapped under the old metal by 5-10 mm then do a series of mig tack welds to position it. make sure it is tightly pressed against the inside of the original sheet metal. practice on scrap first.

go back and split the difference between tacks with more tacks, and cool each one with a wet rag after welding. keep splitting the difference and cooling each weld until you have welded the perimeter. grind the welds flat then go back and touch up any pinholes/pits/craters with more welds. don't even try to do a continuous weld. you may get away with 1/2-1" stiches, but you will be more likely to burn through or warp.

test the tank for holes using water, and if you can't fix a spot by adding weld, grind out the small pitted area and reweld. you can make a copper backup spoon from a piece of copper water pipe if you blow through any local spots. you hold it behind the area to fill with weld, then weld very simple. it acts like a heatsink and won't stick. after you take care of all the holes, then bondo up the joint and paint. you can try a butt joint if you don't like to use bondo, but it will be much harder to keep from burning through and making it liquid tight.

good luck.
mike

I have been playing around with a new Lincoln 135 (it rawks!) to put in a brand new set of underwear on my old '62:



Drivers side is all done. My question, being sort of a noob when it comes to mig, is with technique. I am welding all butt joints (20 gauge steel) and I have found that a slight side-to-side motion (perpendiicular to the joint) seems to flatten out the bead and bite into both pieces. Is this correct? Or should I not have any motion at all?

My gas supplier used to be a Holox store here on the Island, and they were bought out by Air Liquide. Same staff, no real changes. But anyway, I bought my bottle (40 cu ft IIRC) outright which is good because they don't really refill the same bottle, but swap for a filled one so I don't get stuck with a botlle going out of hydro testing dates. The cost to fill the small bottle is almost the same as as the big bottles, but I needed the small one to fit my cart under some shelves in the shop and to help with portability of the whole rig.

I haven't had a problem when the store changed ownership, but I've read horror stories. If you buy a bottle instead of renting (or either way) make sure you keep a file of all receipts and paperwork in case your vendor ever does change ownership. Otherwise you may get in a pissing contest over ownership of your bottle with a new store owner.

Don't forget when switching to gas, you will probaly need to change polarity of the machine. If you have the manual, no prob. If not, its usually just unbolting and switching two leads somewhere in the cabinet and usually close where the torch lead plugs in at the drive system.

Watch out Dude, that can be addictive. I got all wrapped up in a 78 Merc wagon hotrod project for a few years as I was teaching myself to fit and weld. Reskinned most of the hood in sections and replaced huge sections of the "D" pillars and their transition into the rear fenders back at the rear end. Too much fun.

But to your question, yes - I found that on some sheet metal joints where it was too easy to slow down travel speed and burn through, that using a weave pattern spread the heat and made for a bigger weldment and more strength. The down side was on seams that had to be ground smooth it meant more metal to remove and more chance for warping from the grinding heat.

Just recently - like this past year, I was welding up some rotary jigs for a neighbor to hold aircraft wing sections while spraying paint. The material was .120 wall 2X2 square tubing. On a whim I tried some butt joint holder/spacers/clamps that I picked up at Harbor Fright and never got around to trying. The space they leave for laying the bead in a butt joint (about .060 - .100" - I haven't measured them ) makes the weld go so effortlessly. Good penetration, less burn through, easier to track a straight bead, flatter beads. Dohh! Why didn't I try these before? And even with them stuck inside tubes or squares, you can unscrew the wing nut and shake the inside pieces out the end of the assembly. They come in a bag of about a dozen for a couple of bucks.

Never heard of such a thing ... could you post a piccy or two? I'm too scared to ask Google about "butt clamps".

EDIT: Never mind ... found some on Ebay, they look perfect for my fuel tank project, will go check out the local welding place.

EDIT2: Now if only I could find some in Australia! Anyone's seen 'em, let me know!

-----sharks

I passed up on a weekend bike trip to Montreal (wimmuns and booze mandatory) so I could spend it under the old beast (in the dirt) this weekend. Alone.

I think I have a fever. Or need to start saving for another visit to the shrink. Addictions are a bitch.

A friend of mine told me about those clamps. So far I am just "practicing" on the welds where it more or less can't be seen and doesn't matter. I will do the cab corners last. When I get up the nerve.