Welding Rod Dia?

[stevejahr]

Been a long time since I held a torch... but one comment I have read here or as a result of stuff here that really stuck out to me dealt with thinking of the heat sink affects around your weld.  In this case you have one tube right at the end that does not sink as much heat as the other tube.  And sure enough that is the one that melted into a hole.  So need to move the heat over onto the intact tube more and less on the tube end.

Do not throw this weld away, instead see if you can "fix" it by welding up the hole.  That takes creating a mini-puddle at the edge and building it up with rod.  And working fairly quickly back and forth over the edge of the hole.

[Dan_]

One more attachment Pete...  

Print it out, and go to the recycler or sheet metal fab shop and buy some scrap...  Get some  1/32, 1/16 plates, and some 1/8 maybe.  

Do some thick to thin practice too perhaps.  

When you get the mojo working, jump back on the tubing.

Give it about a week of good hard practice, and see how it is going then.

Send in another pic...  Hell, send us one every day.  

[leshoman]

Another good practice, if you are just learning to weld, is to go to hardware or big box store and get short piece 1" x 1" square steel tubing and practice running beads, then wending tees. it is thick enough to learn the basics of melting, heat control, puddles and peddle.rod/heat control. once you get good with it then move to the thinner wall tubing.

[914pete]

Great advice guys, thanks! I practiced some more yesterday just trying to lay a bead down on the same piece of 5/8" .035 without burning a hole through it.  I tried the 3/32" RG45 and it seemed a little easier to work with.  I'm wondering if its because there is more material there to use as a heat shield.  I am getting a lot of sparks though.  Both the 1/16" ER70S2 and the 3/32" RG45 are by Weldcote.  I cheaped out on the equipment and bought the HF Medium duty OA set up.  Couldn't afford the $400 name brands.  I have to say, it seems to be of good quality. 

Question, this kit came with a VM-W-0 tip.  Trying to adjust to a neutral flame, the flame is a narrow cone, quiet, not positive about the color (i'm colorblind) and close to 12" long.  Is that normal?  Seems like a long flame.  Does a 00 tip produce less flame length and would that be easier for me to learn with?  Also, I seem to be getting a lot of slag.  I'm not sure where those chucks of metal in the pic came from but it was from me welding.

[Hugh Sistrunk]

May be a stupid question to ask here, if so just ignore me, but are you cleaning the tubing before you start welding.  Lots of that stuff comes with a oily covering to hold off rust.  Also helps to remove any 'Milling Scale' in the weld area if it is heavy on the tubing.  I think that may be what we are seeing there on the ends where all the rough stuff is, also maybe lending to your 'slag' issue... You should not be having any real slag with this type of welding.  Where did you get your tubing - Wicks Aircraft?  Unlike Dillsburg who only sold German tubing, I understand they sell Chinese and German tubing. -  Just some thoughts of what you have going on there.   Send a picture of your torch flame in the welding configuration, if you can...that may give more info to work with.

[914pete]

May be a stupid question to ask here, if so just ignore me, but are you cleaning the tubing before you start welding.  Lots of that stuff comes with a oily covering to hold off rust.   Send a picture of your flame at the welding configuration your using, if you can...that may give more info to work with.

They were cleaned with acetone prior, however, these scraps have been kicking around a very dirty work station and no, I didn't clean them again prior to practicing on them.  Stupid me.

This is probably a stupid question, should I be cleaning the rods as well? 

I usually use Acetone to clean steel when mig welding.  Ok for AO welding?

[Hugh Sistrunk]

I think the acetone is fine for cleaning the tubing -- I use a wire wheel on one side of my grinder for removing the Mill Scale after I fit the piece just before welding.  That seemed to work for me.  The only time I found myself 'cleaning' the rods was later in the build when some rust started to showing on them, and I would just grip some steel wool in my hand and around the rod to remove the heavier spots of rust... My shop 'sweats' at times and I can get condensation on nearly every metal part in it.  No Climate Control and when the humidity is up here in Texas with large temp swings even the underside of my carport drips... just the price to pay to stay out of the Northern Snow Drifts:-)

[Dan_]

Question, this kit came with a VM-W-0 tip.  Trying to adjust to a neutral flame, the flame is a narrow cone, quiet, not positive about the color (i'm colorblind) and close to 12" long.  Is that normal?  Seems like a long flame.  Does a 00 tip produce less flame length and would that be easier for me to learn with?  Also, I seem to be getting a lot of slag.  I'm not sure where those chucks of metal in the pic came from but it was from me welding.

2 years ago yesterday I made a post about how to set the max and min flame for the tip size.    

At the bottom of that post is a you tube, but it was just to show the inner cone has a fuzzy look to it.   The guy welding in it is working with some pretty thick solid round stock, and the total flame length looks about 6 or 7 inches long..

The information I posted about how to set the torch supersedes any gauge pressure numbers you will see in any manual as far as I am concerned.  But your that says you should be able to turn that thing down enough to weld .035...  If it pops you will have to go down to double or triple aught.  Pretty sure you have a Victor tip.

The RG 45 will throw some sparks, it is basically pure iron (no carbon).  I read that RG 60 has some manganese for a de-oxidizer, but will still spark some.  They all spark some...   I think your biggest problem with the RG 45 is it is 3/32.  Basically 3 times thicker than your tube.

The slag may be from an oxidizing flame or it could be coming from some of the burnt (oxidized) area you welded over from yesterday.

You may want to take the RG45 back and get 1/16" RG60 if they have it.  Other wise save it for something thicker.

[914pete]

I hope I'm not boring everyone.  This OA welding is very new territory for me.  I think I'm getting the hang of it though.  3rd welding attempt pic below.  Regarding the flame, You can see in the pic the flame goes out almost 13".  I'm not sure if it matters, just wondering if that's normal.  I think I had it set pretty much neutral.  There is one thing I can't seem to be able to do when starting the torch.  I followed the instructions below Dan, got a nice no carbon Acetylene flame going then with the Oxygen torch valve open 3-4 turns I started slowly opening the Oxygen regulator and as soon as Oxy starts flowing it puts my flame right out ever time.  The only way I can introduce Oxy is to open the regulator with the torch valve closed then slowly open the torch valve.  Any thoughts?

Also, I think the 1/16" rod is plenty.  I bent the end at a 45 this time which actually helped.  Oh, and I thoroughly cleaned the tubes Hugh.  Less sparks, no slag....good stuff!  I did order a 00 tip though to try as well.  Should be in next week. 
BTW-Thanks for all the info.  Really helpful!

[Hugh Sistrunk]

Yep, your getting the hang of it - A little next step planning may be in order at this time.... I cleaned my tubing in the amounts I was planning to weld at each setting, One day might have been two or 3 - 20 foot sticks, next time it may have been 3 feet to build the rudder pedals - Why am I saying this... once your oily junk is removed, plus the mill scale, this tubing is now open for rusting.  In fact, you may experience some 'Flash' rusting within minutes of removing the torch from the weld.  All normal stuff -   So, while you are continuing to practice up for your first true fuselage weld ups, start thinking about what kind of Primer Coat you want to use, just about any primer should be good.  I am sure there are good recommendation out there. I found it worked for me to plan a cleanup of welds by wire brush or wheel on a drill as part of my End of Day time block.  Then the next day or two when I went out, the last welds were 'inspected' with a fresh eye, touched up with the torch if needed, then hit the welds with the brush, pass some steel wool over the tubing between the welds, wipe off with shop rags and apply a light primer coat to beat back the rust.  Understand that you WILL miss welding areas as your going along, you WILL find open fitments where the tubes mate up and not understand how you missed it.  That was my reason for the 'Fresh Eye' look-over between sessions.  It just happens, and you will catch them so just be patient and vigilant.  Sorry if this seems like simple stuff, it is just things I found out on my on as I went into this ...  If you really want something to think about, consider this.  The first part of the fuse recommended to be put together is the station frames... Sta#1 then Sta#2 and so on... so now that I have finished my plane, I look back and realize the first part I welded was as recommended - Sta#1 - cool, the part that HOLDS the ENGINE ON - Yeah go figure, but everything is set and tuned to those stations, make them good and square... My point - hundreds have done it, you will too - just take your time with the welding, weld each weld with the idea that it is holding your butt up in the air - no rush - no time limit is the way to go.

[Dan_]

Regarding the flame, You can see in the pic the flame goes out almost 13".  

It looks long, but...  I loaned my equipment out 3 or 4 years ago so can't go out to compare.  I never noticed how long the flame was...

I would consider it normal if:

• You lit the torch and screwed the acetylene regulator in until the flame left the tip, then turned the regulator back out until the flame just touched the tip again with the torch valve opened all the way.
  

To know if you had the torch valve open all the way:  As soon as the flame came back to the tip, open the torch valve some more to see if the flame changes.  If it changes you dint have the valve open all they way.  

And:

• You had the oxygen torch valve all the way open when you used the oxygen regulator to set the flame neutral.
  

This gave you the max heat you are going to get from that tip, and the regulators are set, so the length of the fire is what it is.

Now you need the lowest setting...

• Close the torch oxygen valve.
  
• turn down the torch acetylene valve until it smokes.
• turn up the torch acetylene until it don't smoke.
• set the flame back to neutral with the torch oxygen valve.

I would not worry about it going out when you crank the oxygen regulator...  That could just be the coarseness on that particular regulator adjusting screw...  Just be sure you set the max heat with the regulators and the torch is wide open...

[stevejahr]

That flame looks huge and like a lot more heat than you need.  I think a smaller tip will help you a lot.

Looking at your weld, something you need to watch out for is the "cold weld".  This is a weld lacking penetration.  You can have a great bead but if it is only on top of the base metal and not fused in you will have no strength.  One of the indicators for potential cold welds is the edge of the bead.  Looking at the left side of your T the bead has a deep edge suggesting piled bead without penetration.  Up at the top it is much flatter showing good penetration.

This is why cutting apart your weld or destructive testing can be a good learning tool too.  Get in under the bead and see what lies beneath.  That is where the true quality of a weld will be found.

[Poorman2]

[Poorman2]

I have been trying to post this video all morning. It has some great information on how to oxyacytelene weld. I hope this helps.

[s johnson]

Great video.. Thanks for sharing.

Scott J.