Fuselage

[Brock]

These bits and pieces of tubing are all starting to look like something organized.  Looking forward to cleaning off the bench and unclamping to set this bird free.

[Brock]

Tacking up the first flat-cluster made me feel good, like hey I can do this.  But then there was what I call the 3D-clusters.  The first one was a dismal failure (though I claim part of it was due to another project already started).  Nice thing about failures, we learn more from them than we do from the easy successes.  I've some ideas already to see if this cluster can be salvaged.  Well finally, after all the clusters have been done, I know how to make them come out the way they need to be.

[Chuck in Indiana]

Nice work..(looking for that thumbs up emoji again..)

[Brock]

Today I declared this frame fully tacked. Just after this pic was taken I had the joy of unbolting it from the table.  Now to get serious about welding.

[Dan_]

[Chuck in Indiana]

Attaboy. 

[Brock]

Welding every little cluster (big ones too) is taking longer than I had figured.  Clusters can be tricky like this one with eight tubes!  One important lesson, it takes less time to carefully cut and cope the tubes to fit tight than it does to weld up large gaps that should not be there.  I'm not proud about this welded cluster as far as quality and beauty of weld but I am quite satisfied that it is done and looks like it's not going to fail.  Might touch it up a bit.

So, the progress has been, cut-cope-tack-weldsome-weldSomeMore-weldAgain(to fix missed spots).  I've not yet done the last 'weldAgain' part. Skill keep growing.

Question: almost every day I have a puddle "JUMP" up to the tig electrode.  At first I thought i was just dipping in the puddle but now I'm certain the puddle is jumping to the electrode.  Whats up with that and how do I stop it?

Trial fit.  Like a new pair of jeans that need to be checked for fit, today I decided to try-on this airframe.  Looks like I'll need a shorter stool.

[Dan_]

Prolly something causing an unstable arc... 

May have a plugged gas lens or leak in shielding gas hose.  May have contaminated tungsten.  May have bad ground.  May have regulator turned up too high...  

Is the tungsten tight in the collet?  

Might try the ground clamp closer to the joint you are welding...
Could always sell the tig rig and get oxy-acet.

[Chuck in Indiana]

Yeah, that is the toughest cluster on the airplane. I'm guessing, and only guessing is that you are adding filler too close to the electrode. It should be in the first third of the puddle, but I'll bet you have figured that out.  I *may* have mentioned before that learning TIG is a steep hill to climb.  Welding clusters adds a degree of difficulty.
Nice job.. that's not coming apart.

[Brock]

Yes Chuck that's the big one.  The underside of that cluster is pictured about 6 posts earlier (left side).  So you can see with the gaps it was a real challange and I had to go over the weld several times.  The good news is that I'm getting good at fixing blow holes and gaps.  My welds are big as I'm using 3/32 filler.  Haven't yet felt comfortable with the smaller filler.  Everything is a compromose, especally when learning.

[Chuck in Indiana]

My welds are big as I'm using 3/32 filler.

"Maybe" that large filler rod increases the size of the puddle as you dip it to cause a Q tip. (?) The largest I've ever used is 1/16".

[Brock]

Today I picked up a Harbor-Freight "tube roller" and installed a set of 5/8" roller dies from "swagoffroad.com".  Not sure how much use this will get in the future but it's always fun to have a new tool to work with and increase possibilities.

So next was to figure out what diameter to use for the seat tube bend.  Thanks to Chuck's post (https://www.eaglersnest.com/forum/index.php?topic=2197.msg13491#msg13491) I've a starting radius of 34.75". But, at 21" my XL is a bit narrower than plans 24".  I'm thinking it might be more comfortable to use a slightly tighter bend.

Does anyone have comments on changing the bend for the seat back based on the narrower airframe?

[Kamcoman77]

Probably the most ergonomical way to shape the seatback tube is to stretch a heavy cord across the seatback area. Lean back against the cord and have a helper pull it to varying degrees of tautness. When the curve feels just right, take a photo or measure the amount of curve. Bend your tube to match. At least, that's the way Forest Gump would have done it.

[Chuck in Indiana]

Man.. I wish I had that tube roller. I gave up trying to make a round engine mount for the Verner. Now, I have to make a bigger heavier one for the 90 Lambert I'm going to use on the Pietenpol project.

[Brock]

Chuck you are welcome to come over (from IN to WA) and use this bender.  It's much simpler to use than I expected.  Bending the seatback 5/8" tube took about 5 minutes.  I wiped the roller dies and tube with WD40 slid it in and ran it back and forth.  Not even a scratch on the tubing just a nice smooth bend.

So Today I installed the last major tube and hope to start on the landing-gear/strut brackets.