Filler Rods and Wings

[subnoize1]

Yes, I can read, no welding on the wings

Actually I have two questions;

1. I'm still learning to weld. I have a Meco Midget and a set of B tanks. I'm still trying to lay down a perfect bead on a sheet so I'm burning through filler rod like crazy. I ran out of filler rod last night and was looking to find a quick supply of ER70S-6 somewhere and lo-and-behold! Amazon popped up with an OK deal. I've found copper coated ER70S-6 for as low as $6 per pound other places but I ran across 10 lbs for $35 including next day shipping at Amazon.

The question is this rod isn't copper coated, would this effect the weld strength when I build? I always heard that copper was to keep the rod from rusting. It's mostly burned off during the weld. At the moment I'm learning to weld so this doesn't mater but will it during the build?

Here is the product at Amazon to which I refer: http://www.amazon.com/gp/product/B0089VZPK2/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1

2. Learning to weld is a lot tougher than it looks. Is riveting as hard? I would love to start building but the welding parts may take a little longer than I anticipated. So, I would love to start on the wings while I get better at welding. Now, is riveting tough too and I'm going to be frustrated again? Should I buy short pieces of aluminium and drill and rivet it together and practice riveting until both skills are 100% before starting?

Thanks,


JB

 

[schines]

JB,
Sounds like a good deal on the rod, but depending on your climate, it will rust rust quick without proper storage. Have you tried welding .035 tubing yet? It seems easier to me and might make you feel like you are making progress.
As for the wings, if you start on them it will be quite a while before you need to rivet anything! The plans call for cherry pop-rivets, which is too easy to do. Even solid riveting is pretty simple with a few minutes practice.
Scott

 

[subnoize1]

Well, supposedly the rods are coated or polished;

"New proprietary copper free finish for long shelf life and lower fume emission, Rods made from high quality steel"

We'll see just how well they hold up to Georgia fall weather (it does get very humid down here).

I might just start on the wings first. A problem I'm discovering is I need a place to weld that is climate controlled and doesn't have a draft. Right now I rent a crappy house and don't have a good place to weld. I can rivet in these conditions though! I can get the wings done and then at the end of the year when I move to a better place I can start welding stuff.

I might find some tube and start working on that. Right now my little brother thinks I should stay on the plate making beads until my eyeballs pop out. Every so often I cheat and weld together two test plates just so I feel like I'm doing something other than melting wire in a straight line

Thanks, Scott!

JB

 

[EricAos]

Welding Rod storage can be pretty easy. I bought a couple of lengths of PVC pipe, 2 or 3 inches diameter, and a hadfull of caps. Cut the PVC into pieces slightly longer than your welding rod. Glue a cap on one end. When its dry, stick your rod in, and slip a cap on the other end. I use a sharpie, and write what is in each on the cap. Then you can stick a bunch of them in a bucket for easy storage, and keep all your rods seperated. I have rod that has been in mine for several years, and no rust.

 

[n3480h1]

Practice laying a good straight bead on plate is worthwhile, but practicing .035 wall tube T joints and angled joints will teach more about heat control. You'll find that point where you'll blow a hole through the tube, then you'll find out how to get good weld penetration without the holes.

Tom

 

[subnoize1]

Actually, I found the same brand but with copper here;

http://www.amazon.com/ER70S-6-36-Inch-10-Pound-Welding-Manganese/dp/B0089VZPM0/ref=sr_1_3?s=hi&ie=UTF8&qid=1377564351&sr=1-3

Darn good price and you can still get them tomorrow-

I guess after I have the bead down I will go buy 12 feet of the tube and use a pipe cutter to make a bunch of 3 or 4 inch long pieces. That way I can practice coping (fish mouthing) with a pair of MidWest aviation snips and then welding the tubing together.

Speaking of the snips, which should I get? They are either straight or to either side. What is it I am looking for in a pair of aviation snips?

Thanks,

Jb

 

[TrickTransAm]

Others may correct me here, but I think you are "over thinking" a lot of this. It has been my experience that your best tool will be a grinder for getting your tubes to fit tight. Fit is EVERYTHING when it comes to how the finished product will appear. Big gaps require lots of filler rod...your weld will not look consistent if you have to fill big gaps on one side and have a nice, tight fit on the other.

As for your filler rod while practicing, use anything cheap that is a similar metal. Cheap steel filler rod is fine for practicing...as strength does not matter. Also, keep some stainless rod handy...when you get bubbles and porosity, use a dab of ss rod to clear that up. Metal cleanliness will help wonders in making a weld turn out nice. All the scale and oil should be rubbed off with some emery paper (sand paper) so you have fresh, clean steel.

 

[subnoize1]

Others may correct me here, but I think you are "over thinking" a lot of this. It has been my experience that your best tool will be a grinder for getting your tubes to fit tight. Fit is EVERYTHING when it comes to how the finished product will appear. Big gaps require lots of filler rod...your weld will not look consistent if you have to fill big gaps on one side and have a nice, tight fit on the other.

Over thinking it would be coping the tubing with my CNC machine. I'm sticking with the aviation snips. I have enough swarf running around my work bench right now, any more would be a fire hazard.

Besides, even on a good day my oxy-acetylene bead will be every bit of 1/8 to 1/4 of an inch wide so close fits are wasting time. I feel bad for the guys TIGing on this! Now they have to get it close from what I understand. I've been told a small gap that I can fit my filler rod into is where I start with oxy-fuel.


Jb

 

[schines]

Jb,
The rule of thumb I used in building the fuselage was ABOUT a 1/16" gap. Most had slightly more or less - I never measured. I was going for strength, not looks. At one point I expressed concern over my welding skills (or lack there of) to an A&P friend. He showed me a Cub he was re-covering. Most of the factory welds looked better than mine, but a few were worse. The point was that perfection is a dream. Just make it the best you can.
For what it is worth, I tried every method I could think of to make fishmouths. I found that snips are too much work and drill jigs take too long to set up. I ended up just cutting the approx. shape on a band saw and grinding to fit.
As for the snip question, I would get a set of Wiss or another quality brand. Just don't get the cheap Harbor Freight ones. I also found that a large long handled straight shear was good for cutting out rib blanks, etc. Hope this helps,
Scott