Welding techniques for 4130?

I am going to begin an aircraft project this winter and it looks like I have a
LOT of welding ahead of me. I'm curious as to the different methods, ie
brazing vs. arc, etc., and what the benefits or drawbacks of each method may
be. Is one style better? Stronger? Easier? I will be working with a buddy
who owns a machine shop and he has just about all the equipment I could ever
ask for. Given that availability of equipment, what would you welders out
there recommend or prefer?

Thanks.

Tig if not then oxy/ac
"Building The Perfect Beast" wrote in message
...
I am going to begin an aircraft project this winter and it looks like I
have a
LOT of welding ahead of me. I'm curious as to the different methods, ie
brazing vs. arc, etc., and what the benefits or drawbacks of each method
may
be. Is one style better? Stronger? Easier? I will be working with a
buddy
who owns a machine shop and he has just about all the equipment I could
ever
ask for. Given that availability of equipment, what would you welders out
there recommend or prefer?

Thanks.

Tig if not then oxy/ac
"Building The Perfect Beast" wrote in message
...
I am going to begin an aircraft project this winter and it looks like I
have a
LOT of welding ahead of me. I'm curious as to the different methods, ie
brazing vs. arc, etc., and what the benefits or drawbacks of each method
may
be. Is one style better? Stronger? Easier? I will be working with a
buddy
who owns a machine shop and he has just about all the equipment I could
ever
ask for. Given that availability of equipment, what would you welders out
there recommend or prefer?

Thanks.

On 28 Aug 2003 02:00 PM, Building The Perfect Beast posted the following:
I am going to begin an aircraft project this winter and it looks like
I have a LOT of welding ahead of me. I'm curious as to the different
methods, ie brazing vs. arc, etc., and what the benefits or drawbacks
of each method may be. Is one style better? Stronger? Easier? I
will be working with a buddy who owns a machine shop and he has just
about all the equipment I could ever ask for. Given that availability
of equipment, what would you welders out there recommend or prefer?

I'm going to assume you will be welding 4130 steel structures
exclusively. If you are a relative novice to welding, use oxy-acetylene
equipment and mild steel rod. Do a Google search on this newsgroup,
paying extra close attention to posts by Bruce Frank and a guy named
"Highflier." Also, the EAA puts out an excellent publication on
aircraft welding.

As for equipment, if I were buying new equipment I would buy one of the
standard cutting/welding kits from Victor or Harris (now owned by
lincoln electric) mainly to get the regulators and hoses. The torches
that come with those kits are on the large side for welding thin
material, so buy a smaller torch which will be more maneuverable,
especially around fuselage clusters. I've heard good reports about the
Meco Midget, the Smith Airline, and the Henrob (people who have used the
latter find it a bit heavy).

Unless you are already an accomplished welder, ignore suggestions to
purchase an expensive TIG welding machine. It is not necessary and may
lead to undesirable results unless you have already mastered the basics
of welding with oxy-acetylene equipment. I use a small TIG machine and
like it, but I also use it for other things (like aluminum and
automotive projects) and had quite a bit of oxy/acetylene experience
before trying it. If I couldn't afford a TIG unit, I would weld
together my airframe using oxy/acetylene with no hesitation.

----------------------------------------------------
Del Rawlins-
Remove _kills_spammers_ to reply via email.
Unofficial Bearhawk FAQ website:
http://www.rawlinsbrothers.org/bhfaq/

I'm going to assume you will be welding 4130 steel structures
exclusively. If you are a relative novice to welding, use oxy-acetylene
equipment and mild steel rod. Do a Google search on this newsgroup,
paying extra close attention to posts by Bruce Frank and a guy named
"Highflier." Also, the EAA puts out an excellent publication on
aircraft welding.

Thanks Del. That's what I was looking for. I did a Google search and just
came up on too many hits. I was hoping that I might get it narrowed down and
you've done just that for me.


Unless you are already an accomplished welder, ignore suggestions to
purchase an expensive TIG welding machine. It is not necessary and may
lead to undesirable results unless you have already mastered the basics
of welding with oxy-acetylene equipment. I use a small TIG machine and
like it, but I also use it for other things (like aluminum and
automotive projects) and had quite a bit of oxy/acetylene experience
before trying it. If I couldn't afford a TIG unit, I would weld
together my airframe using oxy/acetylene with no hesitation.


Luckily I've got a buddy who is going to build with me and he is a master
welder. I plan on learning a lot from him. As for my experience, well, most
of it is on farm equipment and about all I've ever used oxy/acetylene for was
cutting stuff up. I'm a fair stick welder but I know I've got a lot to learn.
And I'm looking forward to it.

Done properly, do you feel that there is any difference in the quality of weld
produced by oxy/ace vs. TIG? Is the TIG just less hassle or what?

On 30 Aug 2003 19:08:53 GMT, onloser (Building The
Perfect Beast) wrote:

I'm going to assume you will be welding 4130 steel structures
exclusively. If you are a relative novice to welding, use oxy-acetylene
equipment and mild steel rod. Do a Google search on this newsgroup,
paying extra close attention to posts by Bruce Frank and a guy named
"Highflier." Also, the EAA puts out an excellent publication on
aircraft welding.

Thanks Del. That's what I was looking for. I did a Google search and just
came up on too many hits. I was hoping that I might get it narrowed down and
you've done just that for me.


Unless you are already an accomplished welder, ignore suggestions to
purchase an expensive TIG welding machine. It is not necessary and may
lead to undesirable results unless you have already mastered the basics
of welding with oxy-acetylene equipment. I use a small TIG machine and
like it, but I also use it for other things (like aluminum and
automotive projects) and had quite a bit of oxy/acetylene experience
before trying it. If I couldn't afford a TIG unit, I would weld
together my airframe using oxy/acetylene with no hesitation.


Luckily I've got a buddy who is going to build with me and he is a master
welder. I plan on learning a lot from him. As for my experience, well, most
of it is on farm equipment and about all I've ever used oxy/acetylene for was
cutting stuff up. I'm a fair stick welder but I know I've got a lot to learn.
And I'm looking forward to it.

Done properly, do you feel that there is any difference in the quality of weld
produced by oxy/ace vs. TIG? Is the TIG just less hassle or what?

TIG is easier to control. The heat is more intense and localised. The
"flame" is always neutral.

On the other hand, the flame on Oxy Acet is more forgiving. You don't
polute the electrode every time you get the tip too close to the
puddle.

A lot easier to learn to weld with ocy Acet than with TIG.

On 30 Aug 2003 11:08 AM, Building The Perfect Beast posted the following:

Done properly, do you feel that there is any difference in the quality
of weld produced by oxy/ace vs. TIG? Is the TIG just less hassle or
what?

Well, many knowledgable and experienced welders believe that the
narrower heat effected zone (HAZ) causes more stresses to be
concentrated right next to the weld, rather than spread out over a wider
area adjacent to the weld. The problem is that while the weld may be
sound, these stress concentrations might cause cracking right next to
the TIG welds. The cure for this is to either weld using oxy-acetylene,
or to post heat the TIG welds using an O/A torch with the "rosebud"
heating attachment, which stress relieves the joint, moving the stresses
away from the more highly loaded weld clusters, and preventing the
cracking. For every welder who holds this opinion, you can probably
find another equally qualified welder (including the guy who helped FAA
revise the welding portion of AC43.13) who believes it to be a non-issue
and the post heating to be unnecessary.

As a mostly self-taught amateur welder, my position is that I don't know
enough to say either way, but that nobody has been able to convince me
there is a downside to post heating the TIG welded joints, other than
the time and cost of the gases used. My plan is to do as Bruce has
suggested in the past, and not worry about it for the most part, but to
also go over some of the more highly stressed critical areas with the
rosebud. Places like the wing and landing gear attach fittings, and the
tailspring and engine mount points.

For the record, I *really* like my TIG unit (a Lincoln square wave 175)
and I feel that the precision, cleanliness, and convenience of the TIG
process outweighs the disadvantages of cost and possible need to strain
relieve welds. But in your case, since you will need to develop oxy/
acetylene skills anyway before you can even think about trying the TIG,
you should just use the O/A torch for your welding since it is easier
and more forgiving. I already had plenty of O/A welding experience
under my belt and I did quite a bit of welding on non-aviation stuff
with the TIG before I ever started putting aircraft parts together with
it.

----------------------------------------------------
Del Rawlins-
Remove _kills_spammers_ to reply via email.
Unofficial Bearhawk FAQ website:
http://www.rawlinsbrothers.org/bhfaq/

On 30 Aug 2003 19:08:53 GMT, onloser (Building The
Perfect Beast) wrote:

Luckily I've got a buddy who is going to build with me and he is a master
welder. I plan on learning a lot from him. As for my experience, well, most
of it is on farm equipment and about all I've ever used oxy/acetylene for was
cutting stuff up. I'm a fair stick welder but I know I've got a lot to learn.
And I'm looking forward to it.

Done properly, do you feel that there is any difference in the quality of weld
produced by oxy/ace vs. TIG? Is the TIG just less hassle or what?

Done properly there is not much difference and both can produce
similar looking welds although it often takes a while to build up the
skills to produce quality looking welds every time.

Dell mentioned that the cost did not bother him. For me, cost is a
huge issue. I don't weld all the time, and once the fuselage was done
the welding dropped off to a bit here and there, maybe once every four
to five months, if that. So having a $1300 rig sitting in the shop
that wasn't being used doesn't make sense to me when the Oxy/Acet
torch welds tubing just fine. Remember, before there was TIG, ALL
fuselages were built using the torch, and none of them pulled apart.

Remember, you are welding a fillet entirely around each joint. When
you do that, you encapsulate the cluster with filler and fused metal.
It's as indesctructable a connection as there is.

TIG has a lot going for it but ease of use when welding a fuselage
isn't one of them. The handle is heavier to hold for long periods
than a torch and you have to have the foot pedal near by to be able to
use it, or you must buy a hand operated trigger. The handle gets hot
after a while unless you have water cooling, which adds weight and
complexity.

A torch setup will cost around $300 new. The gasses aren't expensive
to rent, and besides, you need Argon for the TIG welder too.

The TIG machine is more versatile and is capable of welding thicker
metals with less distortion, if you need to do so.

Corky Scott

On 28 Aug 2003 22:00:46 GMT, onloser (Building The
Perfect Beast) wrote:

I am going to begin an aircraft project this winter and it looks like I have a
LOT of welding ahead of me. I'm curious as to the different methods, ie
brazing vs. arc, etc., and what the benefits or drawbacks of each method may
be. Is one style better? Stronger? Easier? I will be working with a buddy
who owns a machine shop and he has just about all the equipment I could ever
ask for. Given that availability of equipment, what would you welders out
there recommend or prefer?

Thanks.

Welding means to fuse two metals together by melting them, often with
the addition of a filler.

There are many ways to do that: Stick, Oxy Acetylene torch, TIG, MIG
and some kind of friction method has been developed now. Of those
mentioned, stick and O/A are by far the least expensive. Of those
two, only O/A is recommended as it's very difficult to make a
satisfactory weld on thinwall tubing using a stick welder.

Thinwall 4130 tubing was developed originally to be welded using the
O/A method with a mild steel filler rod. The people who joined the
tubes using this method were really good at it and the welds are a
marvel to look at.

Anyone with the desire and a little understanding and practice can
manage a decent weld on thinwall tubing. The best method for learning
is to take a course, like those offered by Ron Alexander in
conjunction with EAA. You learn by doing yourself under close
supervision and can see with your own eys what constitutes a good weld
and what doesn't.

Brazing hasn't been tried much for several reasons but I understand
that there are brazing rods that are easily up to the task. The only
difficulty is that the brazing process is less able to fill gaps than
welding, so the joints must necessarily be closer in tolerence.

The bottom line is O/A welding is a proven method for joining thinwall
tubing and is no more expensive than brazing so why not weld?

Corky Scott

Actually, brazing is probably more expensive than welding.

Corky Scott wrote:

On 28 Aug 2003 22:00:46 GMT, onloser (Building The
Perfect Beast) wrote:

I am going to begin an aircraft project this winter and it looks like I have a
LOT of welding ahead of me. I'm curious as to the different methods, ie
brazing vs. arc, etc., and what the benefits or drawbacks of each method may
be. Is one style better? Stronger? Easier? I will be working with a buddy
who owns a machine shop and he has just about all the equipment I could ever
ask for. Given that availability of equipment, what would you welders out
there recommend or prefer?

Thanks.

Welding means to fuse two metals together by melting them, often with
the addition of a filler.

There are many ways to do that: Stick, Oxy Acetylene torch, TIG, MIG
and some kind of friction method has been developed now. Of those
mentioned, stick and O/A are by far the least expensive. Of those
two, only O/A is recommended as it's very difficult to make a
satisfactory weld on thinwall tubing using a stick welder.

Thinwall 4130 tubing was developed originally to be welded using the
O/A method with a mild steel filler rod. The people who joined the
tubes using this method were really good at it and the welds are a
marvel to look at.

Anyone with the desire and a little understanding and practice can
manage a decent weld on thinwall tubing. The best method for learning
is to take a course, like those offered by Ron Alexander in
conjunction with EAA. You learn by doing yourself under close
supervision and can see with your own eys what constitutes a good weld
and what doesn't.

Brazing hasn't been tried much for several reasons but I understand
that there are brazing rods that are easily up to the task. The only
difficulty is that the brazing process is less able to fill gaps than
welding, so the joints must necessarily be closer in tolerence.

The bottom line is O/A welding is a proven method for joining thinwall
tubing and is no more expensive than brazing so why not weld?

Corky Scott

--
Bruce A. Frank, Editor "Ford 3.8/4.2L Engine and V-6 STOL
Homebuilt Aircraft Newsletter"
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| on all aspects of alternative |
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*------------------------------**----*
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0 0 TIG welding

While trying to find the time to finish mine.