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DSMITHLIB
06-24-2012, 06:55 AM
I recently completed an RV7 and want to move on to something more challenging. I have my sights set on a scratch building a Cub type. I am training in TIG welding and hoping to be proficient enough to build my fuse next spring.

I am looking for someone experienced with fuse welding that I can chat with to understand what is REALLY required?
Do I need a jig? Where in the US can I find one, or how to build one?
Does 4130 need to be annealled or normalized?
Tricks of the experienced builder/welder.
Best source of materials?
Who is the "go to" guy (or gal) for fuse welding?

Any pointers would be greatly appreciated.
Dave Smith
Libertyville, IL

Max Torque
06-24-2012, 11:12 AM
Dave,

Pick up a set of Tony Bingelis' books - they are a "must have" and the answers to most of your questions are in them.
Yes, you'll need a jig to do it properly - The Wag-Aero Sport Trainer plans show you how to build a simple wood jig and are a good investment.
You'll find proponents of "normalizing" and not "normalizing" 4130. To each his own. I've done both tig "normalized and "non-normalized" and both are plenty strong enough for a Cub fuselage.
"Go to" for welding would be our own EAA - they have a great Aircraft Welding book/video combination http://www.shopeaa.com/weldingbookanddvdcombo.aspx
Cheers,
Tom

Eric Witherspoon
06-25-2012, 12:45 PM
When you get closer to where you want to start welding on some aircraft tubes, you might consider a "tube kit". Yes, there are companies that make just the tube kits - your welding required.

http://cartesiantube.com/aircraftlibrary.html

Still plenty of time in building the jigs and all the rest of the stuff that goes into an airplane from there...

Dave Prizio
06-26-2012, 09:47 AM
Wag Aero sells plans and materials for their Sport Trainer which is pretty close to a J-3 Cub. They also sell prewelded fuselage cages for those who don't wish to do all the extra work. There are plans available for the original PA-18 Super Cub if you want something bigger than a J-3.

You will want to make some basic jigs for the major components to keep everything straight. I suggest you search the archives at www.supercub.org for photos and old posts about building your own Cub.

You can normalize your welds by heating them with a torch and allowing them to slowly cool in a draft-free environment. Not everyone agrees on how effective this is.

Wag Aero and Aircraft Spruce have all the material you need. You may be able to find a local supplier that will save you some shipping money, but you'll have to do some research on that yourself.

The good thing about tackling a J-3 or PA-18 look-alike is that there is a wealth of information and support available.

Best of luck on your project.

Darryl MacDonald
06-28-2012, 08:15 PM
Go to airbum.com and read Budd Davison's articles on welding tubing. Excelent writing and easy to understand.

DennisRRhodes
06-29-2012, 07:18 AM
Check Cartersian Tube Profiling . Not sure of the spelling . But they offer CAD precut tubing kits including the end scarf joints for a number of fuselages. I looked at a breezy at one time. The joint prep is the secret to a good joint fit up and weld out.

Richard Warner
06-29-2012, 08:33 AM
You stated you want to build a Cub type. Besides all the excellent Wag-Aero ones, take a look at the Bearhawk Patrol also. You can plans build it or buy a kit and Wicks sells the complete hardware kit for it. They also say it can be built to LSA standards as well.

tom_walter
07-21-2012, 07:46 AM
Take a look at Eric Newton's web site: www.mybearhawk.com

Eric did everything scratch build, but he was one quick builder!

Fuselage section:

http://mybearhawk.com/fuselage/fuseframe1.html

There are some excellent 4130 video's sold by Tinmantech.com Highly recommended,
DVD's these days, but I kept an old VCR to watch the tapes I have.

Have someone sit down with you and go through the steps on adjusting and lighting.

Tom

Aaron Novak
07-31-2012, 03:07 PM
I recently completed an RV7 and want to move on to something more challenging. I have my sights set on a scratch building a Cub type. I am training in TIG welding and hoping to be proficient enough to build my fuse next spring.

I am looking for someone experienced with fuse welding that I can chat with to understand what is REALLY required?
Do I need a jig? Where in the US can I find one, or how to build one?
Does 4130 need to be annealled or normalized?
Tricks of the experienced builder/welder.
Best source of materials?
Who is the "go to" guy (or gal) for fuse welding?

Any pointers would be greatly appreciated.
Dave Smith
Libertyville, IL

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