Slight Change

The airplane I am building is an almost exact copy of the Piper Vagabond with some changes to make it suitable for homebuilding.

When Piper designed the Vagabond they essentially took the Piper Cub, widened and shortened the fuselage, moved the back seat up beside the front seat, and shortened the wings slightly. 

I chose the Wag-a-Bond for a variety of reasons, not the least of which was the Cub heritage.  A big driver for choosing the Wag-a-Bond over the Wag Aero Sport Trainer, which is an almost exact copy of the Piper Cub, was that I harbored a hope that my wonderful wife, who is very supportive of my aviation activities, would, herself, develop a love of flying in small aircraft. That has not happened and is not likely to happen. 

So I have re-evaluated the comprises I made in choosing the Wag-a-Bond.  The Vagabond, and the Wag-a-Bond are great airplanes. The main reason for choosing the Wag was the side-by-side seating. Getting in and out of the Cub back seat is a bit of a chore. My wife actually had the opportunity of flying in a friend's Cub and found entry and exit to be difficult.

However, by shortening the fuselage in designing the Vagabond, Piper changed the ground handling characteristics of the airplane from quite docile to what is usually described as "quick".  By shortening the wings the airplane was made faster, but changed the flight characteristics that make the Cub such a good low and slow airplane. The side-by-side seating, while friendlier, actually reduces the visibility for both the pilot and the passenger. 

The upshot is that I have decided to switch from building Wag Aero's Wag-a-Bond to their Sport Trainer (Cub-a-like).  Fortunately all the work I have done on the Wag-a-Bond translates directly to the Sport Trainer. I will not have to start all over.  Wag Aero, like the old Piper company, uses as many common components in it's aircraft as possible.

Another consideration is that the Sport Trainer fits more easily into the Light Sport Aircraft (LSA) designation.  The effort necessary to maintain an LSA certificate is less than for the Private Pilot certificate, especially as it relates to the medical requirement.

The plans for the Sport Trainer are on their way.  After I build a couple more ribs and compression struts (longer wing) I will be off and running again.

 

Welding

So where has Reg been?  Reg has been off learning new skills.  Gas welding has come along, but it became apparent that I needed to add TIG (Tungston Inert Gas) welding to my bag of tricks.

After much research and agonizing I broke open the bank account and purchased a TIG welder.

The old timers, and those with deep pockets, will tell you that you MUST purchase a Miller, Lincoln or Hobart welder.  That the Chinese welders (which all the other brands are) are pure junk and not worth the price.

The folks who are actually using the Chinese units have a different perspective.  It is true that some, even many, of the Chinese welders are junk and should be avoided.  However, there are a handful of brands that are very decent units.   Some of the them are designed and engineered domestically and manufactured in China.

Eastwood is one such company.  Eastman has been around for a long time, and the reviews show very few units with problems and excellent customer service when one does develop  a problem.  Their welders come with a three-year warranty.

Obviously, the rub is price. A Miller unit with comparable capabilities and features to the Eastwood that I purchased raids the bank account for just shy of $2,000.  And that is with a one year warranty on the "the box" only.  My Eastwood was $900 (OK, $899.99) including shipping and that aforementioned three year warranty on all components.  The Miller may be a better machine, but it is not over twice as good. I prefer to buy "Made in the USA", but I am not going to cut off my nose to spite my face.

Surprisingly, I have read almost nothing but good reviews about the Harbor Freight TIG welder.  It doesn't have quite all the features of the Eastman, but it is even a few hundred dollars less.  So one can get into TIG relatively inexpensively.

So far the Eastwood has performed flawlessly. The only problems being due to my inexperience. I am constantly having to stop and regrind my tungsten due to touching either the work or the filler rod.

In addition to the welder, you will need a cart, a bottle of argon gas, and a good welding helmet. I bought the cart and a welding helmet from Harbor Freight.  The cart is completely satisfactory.  The helmet not so much.  Buried in the instruction manual it states that the helmet is not suited to TIG welding.  You would think they could put that on the box. All is not lost. It is suited to gas welding and the instant dark feature is pretty handy.  I purchased the argon bottle, filled with gas, from my local welding supply.

And thus started an extended period of practice. Which is why this blog has not been updated lately.  But I am back on track actually fabricating airplane parts.

Today I started the final welding on the compression struts.  The welds are not pretty, but they are structurally sound and getting prettier.

Here are the first four compression struts all welded up and ready to be primed and painted.  It takes about an hour to final weld each strut. Please do not blow this photo up and look closely at the welds. They are not exactly the "stack of dimes" appearance for which everyone strives.  But, as said before, they are structurally sound.

Once the remaining struts (8) are final welded and painted, it will be on to the next step.  Which is fabricating the aileron hinges.  Those will be a lot more complex than the compression struts.

First Compression Struts

Spent the afternoon fabricating and tack-welding the first four compression struts.

These are pretty simple parts, but they are the first metal parts I have fabricated in a long time.  I have been kind of reluctant to work on these.  They are not difficult, but my confidence in my abilities has been a bit low.  But these look great.

There are a total of 12 compression struts.  The remaining eight are of a somewhat different configuration.  Some of them are built from 5/8" tube instead of the 3/4".  The ends, which are Piper Cub parts and not easy to fabricate are sized for the 3/4".  I am thinking of fabricating short 3/4" transition pieces.  So far my attempts in that direction have not been particularly re-assuring.

Standard procedures requires a bird-beak transition in the larger tubing.  So far I haven't been very successful in figuring out how to cut the bird-beak. 

It will come.

COMPRESSION STRUT JIG

This project has been on the shelf for far too long.  This evening I finished up the jig for fabrication of the compression struts.  The compression struts are braces between the wing spars counteracting the pull of the drag wires.

The upright on the left has a rail on the bottom that runs in the groove, maintaining alignment between the uprights while allowing that one upright to be adjusted for length.  It is held in place with a C-clamp.

The components of the first strut are in place ready to be tack welded.  Actually, not.  They need to be cleaned up first. The metal on the jig will, hopefully, prevent me from setting the plywood on fire.  The middle brackets ensure that the tubing will not drop out while the tacking is under way.

Stuff

While the focus is on the interior of the Cessna 150, there is still some progress on the Wag. The materials and parts for the compression struts have arrived and I will start the jig for the struts in the very near future.

Side Track

The Wag-a-Bond is going on the shelf for a short period of time while I do some work on my Cessna 150.

Go to N8346J.blogspot.com link to go to that blog and follow that project.

I will be back here working on the "Wag" in a few weeks.

"Airline" Torch

Some time ago I scored a Harris 15-3 "airline" torch handle on eBay.  I got it for about 1/5th of retail for a new torch.  It was advertised "with box" and looks like it has never been used. The box was beyond salvation.

It took awhile to get all the rest of the pieces to turn the "handle" into a complete torch.  But here it is beside the Victor medium duty torch.

It is the torch on the left.  It is much lighter and works great on small items.  I made a few welds with it last night.  I am very pleased with the lightness and balance.  And, truth to tell, it is a higher quality tool than the Victor. 

Having said that, there are a few adventures in dealing with Harris.  Both Victor and Smith, the other two big torch manufacturers, have easy to figure out tip charts that help choose the tip for the application.  Not so Harris.  It is difficult to figure out what you need.  Complicated by the fact that, whereas Victor (at least) has just a handle and tips, the Harris has a handle, a mixer, a tip tube, and the tip, all that must be matched to the application.

Fortunately, there was someone at the Airgas franchise in Aberdeen, WA  knowledgeable and helpful regarding the Harris line.  He helped me determine what I needed, though it all had to be special ordered, and others at the shop had some difficulties when the one guy was on vacation. 

The Harris 15-3 torch (and other "airline" type torches) was, at one time, very popular with auto body shops.  However, with the way modern cars are built, the auto body shops do very little, if any, welding anymore.  What welding they may do is TIG. With that, the demand for this type of torch has dropped off.  It is now pretty much relegated to us airplane builders (and just the rag-and-tube folks at that) and the few hard core car builders. With the limited market one can hardly expect the local welding supply shop to have much in the way of supplies and accessories on the shelf.

And the welds?

Well, here is one.  It still leaves something to be desired, but that is not the torch's fault.  I am still working on getting a good rhythm in order to produce a nice even weld pattern.  However, though this weld is not as "pretty" as it could be, it is, structurally, a good weld.

I feel that just a bit more practice and I will be able to start on the real thing.