South Jersey Skybolt :: A Radial Engined Biplane

Aircraft Welding 101:
Wanting material things... a putter just won't do it.

May 16, 2007

Out to practice for a half hour that turned into an hour and a half.

Pushing my luck and skill on "advanced" welds 'cause I haven't purchased the flatstock that I need to practice with. AND I haven't taken the time to cut up some thin-walled tubing with notches to fit up to other pieces of thin-walled tubing. THAT's what I need to be practicing on. I'm notorious for thinking like that; thinking that prepping for the job, by cutting practice pieces, is a waste of time, when in essence I need to do it so my "practice practice practice" time wrings out every second of time and makes it productive. Building this plane isn't just a matter of putting in time. It's putting in quality time.

Want to make good use of your time ? Be prepared to practice. aka... have the correct practice material. Kinda like going to play golf and only having a putter. Ever try teeing off with a putter ? Right... same goes for everything, including welding.

The more you practice the more intuitive you become with it. At least that is what I'm finding. Trying harder weld joints ('cause I didn't have the correct material) I attempt to replicate the same "scene", the same look, of easier weld joints. It's work, it isn't always easy, but you at least have a foundation, knoweledge, that you can build on now that you've been welding for sometime. And it does work. All that time you've put into practicing pays off with being able to build on that knowledege and tackle harder welds.

Another point. (You'll find that I repeat myself here. Here meaning right here, now, and here on the site. Repeating reminds me of stuff I know. Just brings it to the front of my cranium.) Know the thickness of your metals. A thin-walled piece being welded to a thick-walled piece won't need any pre-heating beyond the weld area (or hardly any) ... you want that cold metal to suck some of the heat out of it otherwise it's going to burn away. Wanna know how I know this ? It's because I didn't have the material to practice welding thin-walled to thin-walled (thinking positive here.) I knew there was a reason I hadn't done any of that prep work I had mentioned earlier. : )

Tonight... not a complete waste of time. It's actually never a waste of time, "time in the saddle." It's just that I feel I should be making good welds consistently. Then again... if I got the material for practicing maybe I would.

Did I mention having the correct material for praciticing ? I think I now know why I never started playing golf. That putter I have in the closet just ain't gonna do it.

May 23, 2007:
It's a tubular thing...
and a few tips for welding

Back at it. This time using thin-walled tubing.

Welding thin-walled to thin-walled. Fun, interesting... a lot more difficult. Most of the welding you're doing is at various angles. I'm practicing on "T" joints right now. The easy welds... I'm assuming. Not easy right now. It's not a matter of heating the metal, running the bead and adding the rod. Try orchestrating the flame and the rod in harmony around an arc, or 1/4 arc for that matter. All that time spent pushing the puddle and practicing on the straight lines has helped. But I'm beyond the help right now. I'm trying to be coordinated in an un-coordinated environment. The angles that you need to have the torch is one thing and the weld rod is another. Try patting your head and rubbing your stomach. Same thing !

As I had mentioned previously. I know the look of what is suppose to be happening so I play the flame and work it to achive this "look." An hour went by before I knew it.

Either I'm not preheating enough of the tubing or I'm not using a large enough tip. I think I need a tip between the two I have. The large one just seems to be putting out TOO much heat and the smaller one just isn't doing the job. I'm waiting and waiting and waiting for the puddle to form, even AFTER I've preheated the areas surrounding it. AND there isn't too much tubing to begin with. I'm working with pieces that I've cut down to about 6".

Another problem with the practicing. I'm not letting the puddle "age" enough, because of the tip issue, and when I stick the rod in the undeveloped puddle it sticks. When I go to pull it away I pull the entire piece I'm working on with the rod. I'll need to make a little jig for holding these pieces while I practice. Seems like half the building of a plane is in the jigs you make.

Getting back to the welding topic. I was happy with my progress with the first two "T" joints but my third, and final, joint I just couldn't get the right heat, which I'm alluding back to my earlier comment on needing additional size tips for the sizes in between the two that I have. That's a part of the learning too... knowing and getting the right equipment.

Lessons learned... I hung the torch up for the night... ready to put in another hour of pushing that puddle tomorrow night.

June 6, 2007
...finding the groove

Another night of practice practice practice... practice. It's been about a week since the last practice session.

I had trouble finding that groove I had earlier when welding flatstock to round tubing. I couldn't find the right flame length to keep it from POPPING. I couldn't find the right flame length to generate enough heat to get the weld puddle going. I couldn't get both metals to form puddles that would allow me to add the weld rod to make a decent weld joint. I couldn't find much... to say the least.

The only thing that kept me going tonight was thinking back on the nice weld lines I was getting welding flatstock to round tubing. I knew I could do that. That use to be as perplexing to me as this is now. I know it's just a matter of time, aka practice, before I'm making nice weld lines with the thin-walled to thin-walled tubing.

The first steps in learning something isn't necessarily doing it right the first time out but to chip away at the misunderstanding. The more I chipped away tonight at that misunderstanding the more I learned.

A carry over from my last session... whenever I worked on a 90° weld joint I was getting an undercut ahead of the weld. I really had to work at getting anything that really looked nice. Another "I couldn't figure it out" until tonight. You need to run the flame of the torch down the groove of the "V." Up until the moment that this was revealed to me I was working the weld joint from the side of the joint. Running the torch down the "V" of the joint also seemed to run the puddle evenly on both metal surfaces.

It wasn't until the last 10 minutes of this practice session that I discovered this "trick." I found the groove. The puddle started flowing, the rod stopped sticking, the torched stopped POPPING. The heavens opened and another mystery revealed. After all these hours of practicing I know when everything gels and comes together. Tonight my world was in harmony (after hours of hell.) You get that excitment going when the puddle flows and the rod you're feeding it .... ahhh it's hard to explain. You just know it's right.

I finished the weld line I had started. A nice looking one at that ! : ) A total of 2.2 hrs in the garage workshop. I refused to leave before I learned something. As it turned out, it was a nice weld line on a 90° weld joint. Tonight I got a glimps of that groove again.

Puddle flowing... I quickly took my lesson, packed up and called it a night. Now if I can only recall what I learned when tomorrow comes.

June 7, 2007
staying in the saddle

Fired up the ol' torch again tonight. A lot of learning going on. Found that groove last night... tonight it just seems like I'm falling out of it every now and then. More nows than thens.

Had the puddle flowing tonight. Just never really seemed to flow nice. Rod sticking... more popping... more adjusting... Ran out of cut and filed "practice" tubing to use. Went through that stack fast. Had to practice on what I had which wasn't much.

I know what I'm looking for. I've been there a few times. Just more of that practice, practice, practice. Time in the saddle as I say... I only wished it had a seatbelt.

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