# Welding questions



## SE18 (Feb 21, 2008)

These are beginner questions but I thought perhaps I can post them here in this section. Hope you don't mind. Quick background: I was going to buy myself a lathe for Christmas but after seeing the prices, I decided that can wait another year or 2, so I can get a better one with more working clearance. So, I've decided to spend less on a tool I feel I could really use a lot and have always wanted. That being welding gear, to make those cool bridges you guys are always posting, and also to make some 7/8 scale trains from steel. After all, if it ain't steel, it ain't real.

I've been rumaging through the HF website and am totally confused by all of the welders listed including: spot welder, bandsaw blade welder, Mig and flux wire welder, arc welder, inverted arc/tip welder, and plasma cutter. It's daunting! And further more it seems you have to know which accessories to get as they don't seem to come in a complete package, ready to use out of the box.

So here goes with all the questions. I'll number them to simplify:

1. of those I've listed (or maybe not listed), which welder would suit me best for what I want to do?

2. given the one you recommend, which accessories do I need (e.g., helmet, welding wire, welding gloves, clamps, multiple welding tips, oxygen and acetylene and the tanks which hold them, weld hose, plasma cutting tips, regulator gauge)?

3. Are heat sinks necessary like when you solder for doing close-in, fine work?

4. can the welder you suggest also be used to cut metal?

5. Can all types of metal, including copper, aluminum, be welded with the one you suggest (my main metal I wish to weld is steel, others would be nice but not a must)

6. Can metals be sweat soldered using welding techniques similar to what plumbers do in joining copper pipes? 


7. Are fluxes needed and do the surfaces have to be sanded or cleaned before welding? 

8. Can broken bandsaws be rejoined (I know the bandsaw blade welder can but what about other types) again, this a a nice to have but not necessary feature

Thanks so much for any advice you can give. My main factor in answering the above is cost. I want to keep the cost way down and not get the Cadillac plan.

Merry Christmas and Happy Holidays

David Vergun


----------



## altterrain (Jan 2, 2008)

http://www.lincolnelectric.com/know...xcored.asp 

-Brian


----------



## xo18thfa (Jan 2, 2008)

David. For building steel bridges I would recommend a small 110 volt Mig welder from Home Depot. They are inexpensive and easy to learn. I bought one a while back and use it for 1/16" and 1/8" thickness with great success. The welder uses a wire that contains the flux. You pull the trigger and the wire feeds out and it welds. The set I got came with all the accessories needed to get started. A spool of wire, a face shield, chipping hammer, wire brush, instructions good to go. Wire spools are available everywhere when you run out.

There is a bit of a learning curve so you should practice with it before starting a real project. I found that the lower voltage setting is better. You have to weld slower, but you get a bigger molten puddle, deeper penetration and less chance of burning a hole.


The flux wire smokes a little and there is some splatter. Some guys complain about that, but it's not that big of a deal to me. Once in a while you have to clean the surface, but quick rub down with the wire brush and you are in business.

I would say for a hobby project like a steel bridge, a little Mig set up is a good way to go.

Mig will not cut metal, or weld non ferrous or solder. 

Review the Lincoln document Brian referred to because it helps greatly to learn how to cut "V" grooves in the stock for deeper penetration and nicer fillets.


----------



## xo18thfa (Jan 2, 2008)

A friend of mine has a plasma cutter to cut sheet metal up to 1/8" It is sweet, but pricey. I think it cost him about $1000. t also requires a bottle of inert gas you get from a regular welding vendor.


----------



## armorsmith (Jun 1, 2008)

David, 

xo's advice is generally accurate with the following corrections/additions. 

1. MIG welding is easy to learn. It is also easy to make cold welds that will not hold up over time. DO practice and practice and practice before dong a real project. I would also advise cutting one or two of your parctice welds in half (crosswise) and inspect the weld to make sure you are getting good fill and penetration. 

2. You can go to your local welding supply (if the box store doesn't have it) and purchase an anti-spatter spray. This will make cleanup of any spatter a breeze. Just spray the area to be welded before you start (it is weld thru). 

3. No, MIG will not CUT, but with the proper wire AND shielding gas, it WILL weld non-ferrous (aluminum, brass). That being said, for non-ferrous in the thicknesses we work in, I would much prefer a TIG torch. TIG will also weld steel, however the cost of a setup will be higher than the inexpensive MIG units you can purchase from the box stores. 

Welding is an art. I would recommend an 'adult night course' maybe at your local trade school or college. They can be an invaluable launching point 

Good luck and Merry Christmas. 

Bob C.


----------



## SE18 (Feb 21, 2008)

thanks all, I did read Brian's article on way home on VRE and the MIG looks like the one to use for hobby use (thinner metals, less spatter, easy to use). It does look like I'll have to purchase/find the gas that goes with it. 

Recommends using it indoors so the gas won't blow away, but isn't the gas toxic? I'd use it in my garage on cement floor w/lots of clearance, of course, not in the house. 

Thanks


----------



## daveyb (Feb 28, 2009)

mig is good for steel and aluminium, for steel the gas is co2 or an argon/co2 mix the purpose of which is two exclude oxygen in the area of fusion,,,, thus preventing oxidation,,,

ie,,the black sooty deposites.....and splatter

the cleaner the material the better the finish and less splatter

better to use it inside as outside the gas can blow away leading to oxidation, splatter, poor quality weld , gasless wire is available for windy conditions but the results are not as good

some migs are also capable of spotwelding,,, ie automotive type spotwelds,,, with an add on contraption,,, but usually i drill a hole in the top piece and fill the hole fusing the pieces together

aluminium can be welded,,, bit more tricky,, use pure argon gas and the wire must be changed to aluminium,,,

i imagine stainless can be welded this way also,,, unsure of the gas req


my top tips,,,,,,

clean the materials

the reacting face masks are brilliant and are relatively cheep

wear ear muffs,,, a spark fizzing down your lughole is v v v unplessant,,

fireretardent overalls and take precautions against fire,,, clear area and have a fire xtinguisher handy

if you live in a damp climate remove the migwire as it will go rusty,,,, wrap it in clingfilm and hide it in the house where its warm


----------



## armorsmith (Jun 1, 2008)

Yes, Stainless steel can be welded with a MIG unit, however you will need to be careful with the specific alloy of stainless to use the correct wire. Pure argon will work for almost any material, including steel. 

In general, be sure to have ALL parts of your body covered with a dark colored material. The arc flash produced by MIG or TIG is VERY bright and will give you a severe burn (sunburn) if you are not covered. I speak from personal experience. Wear a good quality welding glove, hot metal will hurt when you grab it. 

Happy Holidays 

Bob C.


----------



## Les (Feb 11, 2008)

Daveyb wrote:" ...but usually i drill a hole in the top piece and fill the hole fusing the pieces together."

Brilliant. Simply brilliant technique.

Les


----------



## MasonsDad (Feb 7, 2008)

Some really good questions, I would like to recomend the Clarke EN 180 wire feeder it come ready to weld with or without gas at no additional cost to the machine outside of getting the mix gas or argon, and in that i recomend the standard mix gas Co2 and argon mix its useable in just about all carbon steel welding . and using a smaller wire than .030 helps too, I prefer .024 wire as it is alot easier to handle in those delicate thin sheet metal and or tubing. As far as cutting the sheet metal i have my own shear and pressbreak however in some cases i also have a small Hobart 250 ci plasma cutter that really does the trick , it requires nothin outside of the machine except a good 15 amp 110 volt circuit and has a built in air compressor so its virtually self contained and really simple to use and its good up to 3/16" steel or whatever you may be cutting. Aluminum can be used in the clake wire feeder i mentioned use the .030 and striaght Argon, and if you can find it if welding stainless try to get the dual sheld stainless weld wire because the spatter you get with standard stainless hardwire can sometimes be hard to get off / cleaned and i use Co2 with my stainless wire. Gasless wire is good but it too leaves alot of spatter and cleaning, I will go further into detail with your other questions later on but i hope with all the replies you get from this post helps you out. 
My Clarke welder is also a Miller welder knock off too, I prefer Millers as it tends to drive a more stable arc in fine detail welding which you will find better when approaching a finished product, and what I meant by " knockoff" means it says Clarke otside but inside is all Miller.


----------



## SE18 (Feb 21, 2008)

thanks! I knew I'd get answers here. A lot to chew over. Within a few weeks I'll make a selection and start welding. I'm already thinking of the possibilities--endless. 

I mention cost as being big factor. Was looking at this: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=55525

Is there a compelling reason to move up to a more cadillac version? Like this: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93793 

Dave


----------



## John J (Dec 29, 2007)

Check out "Welders two legged" in this form for some great tips on welding. The tips the guys gave me there inproved my welding skills by 100 % 

I found plasma cutters on E bay between 300 and 500 on Ebay. I got mine out of Albuquerque NM 

My Wire feed welder caome from Home Depot. 

Once you start there is no end to the stuff you can build for your RR. Bridges of all kinds. Bridge supports of all kinds. Even supports for Water Tanks. 

You will be so glad you made the effort to learn welding.


----------



## SE18 (Feb 21, 2008)

ok, now what's the plasma cutter? That might be beyond my price range. 

Just checked HD http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053 

Looks pricier than HF but might come with more accessories?


----------



## ShayCrazy (Dec 27, 2007)

I know everyone is onboard with the Mig welders but I am a big fan of oxy acetylene. With a small tip and a filler rod one can weld small tubing fairly easily. As far as versatility goes it is hard to beat a good gas rig. You can solder or braze with it and you can cut metals. It takes a little more practice but you can become very proficient with it. Best part is you can get set up for less than $200. For practice I used old wire coat hangers. They are super cheap and after a quick wipe with lacquer thinner they behave just like mild steel filler rods. I have repaired things around the house using them and the welds seem to be just fine. If you go with gas the learning takes a little more time but the versatility is well worth it. All you will need is a medium duty rig with a striker (don’t use a lighter, you will blow your hand up), goggles and heavy gloves. I would recommend reading Budd Davisson’s article on gas welding. http://www.airbum.com/articles/ArticleZenWelding.html It is focused on full scale aircraft welding but the techniques can be applied to small scale steel too.


----------



## MasonsDad (Feb 7, 2008)

As Far as Wire feed Welders from HF I personally stay clear of them, I found they have way to much plastic in the internal parts and they become overheated to easy, My Clarke was 599.00 with a cart and its paid itself off more times than the rest of my equipment.


----------



## armorsmith (Jun 1, 2008)

ShayCrazy, 

I agree with everything you said, right down to practicing with coat hangers. That is how I learned gas welding. However, the caveat to that is the heat pull that can be introduced into the structure. The additional heating time of the gas process creates a larger heat affected zone, spreading more heat through the structure, increasing the stresses. MIG is much faster making the weld, smaller heat affected zone, less stresses. 

SE18, 

The most base analogy I can make would be that a plasma torch to metal work is like a hot wire to foam board scenery. A plasma torch will cut just about any type of metal - steel, aluminum, brass, stainless steel, and exotic metals most modelers will never see. They are a great tool for a professional metal worker to have, but for a hobbiest, unless your budget has long arms and deep pockets, is a tool I don't see most modelers needing. I do most of my metal cutting with an abrasive cutting wheel in an 'angle grinder' type of tool (one specifically for this type of work). As long as it is straight lines, I have cut everything from 26 ga steel sheet to C8" channel at 11.5#/ft. I have an acetylene torch, but rarely use it unless the cuts need to be round in some form, or I need to bend heavier thickness which require heating first. 

Bob C.


----------



## SE18 (Feb 21, 2008)

ShayCrazy, 

I really enjoyed the Zen of the Puddle article. I'm very glad you've offered a different perspective, making my choice that much harder. One concern I have is what Bob mentions, regarding the larger area being heated. I'm thinking this could be addressed with heat sinks when doing relatively fine work in relatively close proximity to other parts. The other question I have is your practice with coat hangers. Of course those wouldn't be useable in an actual project b/c the rods you purchase for this purpose have some sort of inert gas in the rods that are released during the heating process, thereby avoiding oxidation. 


The gas setup would certainly be useful for other things around the house, like, for example, adding fixtures to my home gym or making a rack for my kayak. 

An aside. Let's hope aircraft mechanics know the zen of the puddle so we can all fly safe. Enough things to worry about in the air, if you know what I mean. 


oh, 1 more question, would the gas type operate on 115V circuit (standard household electric). Also in using either the gas or MIG, would a separate electric circuit need to be devoted to the welder? (I read this in Brian's article link near beginning of this post). 


Dave V 

Thanks


----------



## ShayCrazy (Dec 27, 2007)

Dave, glad you enjoyed Budd's article. I really enjoy the way he writes. I found another web site that might be of interest to anyone who is welding... http://www.weldingtipsandtricks.com/index.html he is a little bias towards TIG welding but then again I would be too if I could afford a $2500+ machine. It is true that gas will heat a larger area however this usually isn’t a big problem. It can be hard to weld thin material to thick but with practice it will come. It is all about tip selection, they make small jewelers torches that weld gold rings together. 

As for using coat hangers, they work pretty well. For doing some "quick and dirty" welding I wouldn’t hesitate to use them. If the torch is set up correctly the puddle is quite quiet. You get a bit of oxidation but not enough to cause you any real problems with weld strength. In fact a lot of the time you can just butt up the two pieces together and melt the seam together with no filler rod. Actual mild steel filler rod has few additives that consume the oxidation and keep the puddle quiet but over all it is pretty much mild steel. 

Budd's site is aimed towards amateur aircraft builders. In Canada and the US it is possible to buy a roll of plans some metal tubes and start building your own airplane with no experience at all. That is why we spend a lot of time learning the techniques to build a safe airplane. Thankfully you won’t get into one of these airplanes with out knowing, they have the word "experimental" written in big letters in the passenger compartment. I am currently working on a Culp Special, it is an aerobatic biplane and the whole fuselage is welded from 4130 Chromalloy tubing. It is neat to work with a welding torch and stick metal together, very relaxing! 

For welding larger projects I would defiantly recommend a Gas set up over a MIG. It is possible with MIG to get a cold weld where you just add filler material and not get a lot of penetration resulting in a nice looking joint but not a lot of strength. With Gas you don’t add filler material till you have the base metals melted well and flowing together, it all comes down to tip selection. Plus with the fluxes and rods out there it is possible to weld exotic metals like aluminum or stainless steel with out changing anything. 

As far as electricity goes the gas set up needs no electricity. You might want 110V for a grinder or a lamp but it really isn’t needed. MIG it depends on the welder you get. There are ones that operate on 110V and some that need more. 

Hope this all helps. I know what ever set up you get you will wonder how you ever got by with out it. 

Cheers 

Adam


----------



## John J (Dec 29, 2007)

Posted By armorsmith on 25 Dec 2009 10:19 PM 
ShayCrazy, 

I agree with everything you said, right down to practicing with coat hangers. That is how I learned gas welding. However, the caveat to that is the heat pull that can be introduced into the structure. The additional heating time of the gas process creates a larger heat affected zone, spreading more heat through the structure, increasing the stresses. MIG is much faster making the weld, smaller heat affected zone, less stresses. 

SE18, 

The most base analogy I can make would be that a plasma torch to metal work is like a hot wire to foam board scenery. A plasma torch will cut just about any type of metal - steel, aluminum, brass, stainless steel, and exotic metals most modelers will never see. They are a great tool for a professional metal worker to have, but for a hobbiest, unless your budget has long arms and deep pockets, is a tool I don't see most modelers needing. I do most of my metal cutting with an abrasive cutting wheel in an 'angle grinder' type of tool (one specifically for this type of work). As long as it is straight lines, I have cut everything from 26 ga steel sheet to C8" channel at 11.5#/ft. I have an acetylene torch, but rarely use it unless the cuts need to be round in some form, or I need to bend heavier thickness which require heating first. 

Bob C. 

Coat Hangers?







Do they still make them?


----------



## ShayCrazy (Dec 27, 2007)

A good source for wire coat hangers is the local thrift store, sometimes they even give them away!


----------



## SE18 (Feb 21, 2008)

Thanks again Adam, John, and all the others who've been most helpful. 

I haven't made a decision and think it worthwhile to read, reread this post. I've already found a couple other welding posts in this section of the forum as well. I have a $100 amount on my HD card I need to use up too. I'd rather go with the lower cost HF instead, but you guys scared me out of that, with all the talk of plastic parts


----------



## SE18 (Feb 21, 2008)

OK, what about this: 

http://www.homedepot.com/h_d1/N-5yc...ogId=10053

Does all the way down to thin 16 gauge and all the way thick; probably a good compromise 

and does this helmet work? some are 3 times that expensive: 

http://www.homedepot.com/h_d1/N-5yc...ogId=10053

Are there more things I need besides this? I see dollars adding up rapidly. 

Thanks! 

BTW, a friend told me there are bargains on Craigs List. i checked the Washington DC listings for welding and the ones I saw were pretty darned close to the store prices.


----------



## John J (Dec 29, 2007)

If you are going to build things for your Rail Road than I think that is too big. The Mig or Tig wire feed is where you want to go for smaller projects. I have one of the big ones for welding on my back hoe and making big stands and tables to work on. 

It is amazing what you can do with Mig or Tig Wire feed welders.

I have a Self darking helmut from Harbor Freight that seems to work well. 

I have become a Pack Rat. I have been bringing home scrap steel I find around.

Got to constrution sites and take home ( With permission) Unistrut and other steel they may have around 


One of the rigging companies in here town call me when they have stuff from steel crates I can use.


----------



## ShayCrazy (Dec 27, 2007)

Dave, I think you need to get a little hands on experiance. If you have some local modelers with this equiptment they would probably be happy to show you who to operate their personal choice. A good source might be the local high school or trades school. I found that most shop teachers are very willing to share their expertise. 

The welder in your link looks to be a little large for your use. It is what they call a stick welder. You can weld thin materials but it is very difficult and it is very hard to make an attractive weld. 

They have a nice gas set up: http://www.homedepot.com/webapp/wcs...langId=-1&catalogId=10053&productId=100341070 

All you need is gas and gloves for that one. Gas is available from local welding depots on a lease agreement. 

If you have any more questions feel free to ask. 

Adam


----------



## John J (Dec 29, 2007)

I use a lot of 3/4 x 3/4 1/8 wall tubing for bridges and such. With my Lincoln wire feed I some times burn right through the tubing wall evan at the lowest setting.


----------



## SE18 (Feb 21, 2008)

Adam, 

That setup seems to do a lot and the price is perfect. Can the gas be purchased like you get propane for your BBQ (where you get a tank full and then bring it back when you're done and trade out for a full one)? I might only use it a couple time a month so I don't know about leasing as that implies doing a big job in limited time. I'd rather get a book from the library and learn on my own rather than take a class as I have a long commute and don't get home until late at night and busy weekends. 

I might pick up this setup today. 


Thanks so much for this info. 

John, thanks for the tips. 

Dave


----------



## SteveC (Jan 2, 2008)

Dave

Not trying to put a damper on your direction/choice, but since you're tending toward the gas side of things. One thing that as yet no body has mentioned is that you do need to learn about "what to do" and "what not to do." One thing that gas rigs do that electric types don't is explode, if not handled properly. So it might be a good idea if you've got a trade school, adult education, or some such available to take advantage of getting the basics learned from a source that is reputable. I know, now all the comments will come out of the woodwork about being overly cautious etc. etc., however when you don't have any knowledge in a given area it's a good idea to gain hands-on experience under the supervision of somebody that knows what they're doing.


----------



## ShayCrazy (Dec 27, 2007)

Steve is right gas welding can be very dangerous, if not respected properly. That being said if you follow the proper procedures the risk is minimized. If you follow this link, there is a great series of articles that will walk you through how to set up and take down a gas rig. http://www.weldingtipsandtricks.com/cutting-torch-safety.html I agree completely with Steve as far as getting a little help the first couple of times using a gas rig. 

As far as tanks go, yep they can work just like BBQ propane. In Canada we have a company called Praxair. You can sign on for a lease with them I believe it is $40 a year per cylinder (1 oxygen and 1 acetylene) for that $40 they take care of all the valve maintenance, hydrostatic testing ect ect. All you do is go to the local Praxair depot and swap out your tanks for filled ones. It usually costs around $40 a tank to swap them. This is by far the easiest. You can buy your own cylinders, but then you have to worry about all the stuff I mentioned and the initial purchase. When I bought mine I bought MC size tanks. They look like little Scuba tanks and hold enough gas for some small welding projects. If you are just welding (not cutting) these should last quite a long time. The industry calls them Burglar bottles because they are so portable. If you look in your yellow pages, you should be able to find welding gasses under welding equipment. They might even know of a local guy who would show you a few things. 

Hope this helps! 

Adam


----------



## SE18 (Feb 21, 2008)

Thanks, Adam, Steve. 

The cool thing about the gas rig is that if you see/get permission to salvage something, you can use the rig to cut it up, avoiding oil or gas anywhere near, of course. That would call for the small tanks I notice they sell with this setup (I looked last night at some in Lowe's). 

I went to the bookstore last night and read a lot about gas welding and the 101 ways to blow yourself up. I didn't know there were so many ways. So what I'll likely do is find someone with experience with these and mentor along, as well as continuing to read all I can. Thanks again everyone for all the advice.


----------



## Les (Feb 11, 2008)

Posted By SE18 on 31 Dec 2009 07:18 AM 
Thanks, Adam, Steve. 

I went to the bookstore last night and read a lot about gas welding and the 101 ways to blow yourself up. I didn't know there were so many ways. So what I'll likely do is find someone with experience with these and mentor along, as well as continuing to read all I can. Thanks again everyone for all the advice. 


Dave,

I've been following the thread but had nothing better to offer than the excellent advice you are getting. As for finding someone else to mentor you, can I suggest that if you buy your rig, read up and start slowly, you might be better off. All welder-folk have personal tricks 'n tips, some of which are better than others. You might, if you're worried about your mustache (if any ) get a used, cheap arc welder's helmet and take the green glass out, just leaving the clear protective glass. I always wear gloves when using it as a cutting torch, and not when using the small tips. Anyway, you'll have face protection from 'Pops' and you'll get a few. After you gain confidence, lose the arc helmet. Use the welder's goggles underneath the helmet.

Just a thought.

One other thing I've been meaning to build myself for years is a foot-operated, bench mounted torch setup so you can heat and then bend quickly. You step on the pedal and it strikes the flame and admits gas. (Not in that order, necessarily, but you get the idea.) I forget what they're called in the trade, but I bet you can get some input from some of the guys who've already posted.

Les


----------



## Michael Glavin (Jan 2, 2009)

Smaller welding tanks are owned verses leased, they are typically 10, 20 & 40 cu.ft. The small 10 cu.ft. cylinders available at HD and Lowes are typical of portable rigs used for HVAC or refrigeration work, handy but you pay more for less when it comes to bottle exchanges verse the larger bottle sizes. Most HVAC wholesalers offer exchanges as well as local welding suppliers. It may or may not be of concern but some of these torch rigs are oddballs and hard to find replacement welding tips that fit. I'd suggest you look hard at a product from your local welding wholesaler for repairs and parts as they can't help with other stuff. 

The small mig welders available at HD are consumer products and are not the same as those available via a welding supplier, for a few more bucks you can purchase a better Lincoln mig at your local wholesaler... Been there done it, we have four of the 110v migs (Lincoln/Miller) in play in my company we use them in the field regularly primarily for welding .065-.095-.125 square and round tubing they work great for light material... 

Michael


----------



## John J (Dec 29, 2007)

This is the Welder I got. It is from Home Depot and was around 250 bucks 











This is What I built with it.












I also got this for about 350 Bucks on E bay Buy it now Auction.











This is some 2 x4 x 1/8 steel tube.

This is my very first cuts with this cutter. I am still learnging about it.


----------

