Welding techniques for 4130?

On 2 Sep 2003 18:41:07 GMT, Del Rawlins
wrote:

On 02 Sep 2003 04:24 AM, Corky Scott posted the following:

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.

That's not totally accurate, since the cost of the unit was definitely
an issue. If all I were going to do with it was weld together one
fuselage, I wouldn't have wanted the TIG unit.
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Sorry Dell, didn't mean to imply anything. Should have said that I'm
speaking only for myself. So it's very accurate for me. :-)

Corky Scott

"Joe Maj" wrote in message
m...
I was one of those instructors, and I always state that R45 is

Anybody interested in a gas welding aluminum class for next year? It
gets asked for a lot, but we haven't done it much since Lloyd Toll
stopped instructing.
\

I would be there.
--
Jim in NC

On 02 Sep 2003 06:32 PM, Joe Maj posted the following:

In fact, a young guy who was
supervising the welding said that if you followed the older guys
advice you would blow up your shop, cracking the valves before
attaching the regulator.

I didn't say it, but I agree, don't crack valves.

Why not crack the valves? I was taught in welding class years ago to
always crack the valve briefly before installing a regulator. The idea
was to blow out any dust that had settled in the outlet so that it
didn't get into the regulator. Have I been on the verge of disaster all
this time?

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On 3 Sep 2003 04:01:49 GMT, Del Rawlins
wrote:

:On 02 Sep 2003 07:41 PM, posted the following:
: Define "crack."
:
: Open slightly, for a moment?
:
: Or open slightly, and leave open slightly?
:
: If the first, you're fine. I suspect people are worried about the
: second.
:
:I meant the first. To do the second would be retarded and useless.

Yes. But stupidity is the only universal capital crime. And you
should never underestimate the human capacity for stupidity.

This is really getting some odd information presented here. The filler
rod intended for use with 4130 tube used to build a fuselage is MILD
STEEL. The weld is stronger than the tube even though welded with MILD
STEEL. Choices for filler are things like ER70s-6 or -3 or -6. And
several variations, some with additions to the designation like D2. All
will do the job from a metallurgical point of view. I find ER70s-6 to
suit me best with both Oxy/Acet or TIG, though you might want to sand
the copper plating off before welding with it (some find the copper
interferes with the flow of the filler in the molten puddle).

The only time 4130 should be welded with 4130 material is when the part
is going to be heat treated. A novice welder can get into trouble with
undetectable cracking when welding with 4130 filler wire. Heck, even the
experts can find problems with 4130 material used for filler.

A small side note, there are fillers that exceed the strength of heat
treated 4130 that weld as smoothly as if shaping soft butter with a
table knife. You can weld the part more easily than you can with mild
steel then heat treat with no chance of cracking or embrittlement of the
fillet. Sorry, TIG welding only...and expensive.

--
Bruce A. Frank, Editor "Ford 3.8/4.2L Engine and V-6 STOL
Homebuilt Aircraft Newsletter"
| Publishing interesting material|
| on all aspects of alternative |
| engines and homebuilt aircraft.|


"Matthew P. Cummings" wrote:

On Sat, 30 Aug 2003 13:30:40 -0700, Joe Maj wrote:

I was one of those instructors, and I always state that R45 is
completely satisfactory for gas welding 4130 steel. I use it myself.

The older guy giving it said that nothing but 4130 is acceptable now, and
furthermore you do not need to stress relieve, but then a younger guy,
maybe you, disagreed with what he said. In fact, a young guy who was
supervising the welding said that if you followed the older guys advice
you would blow up your shop, cracking the valves before attaching the
regulator.

What did people think of the OSHA-industrial-grade lecture on gas
welding safety? Having listened to it twice a day for a week, I think

I thought for a person who's never been behind the torch it was
appropriate, however, if you've welded it was much too long.

don't express an opinion, we'll all have to go through that again next
year.

I suspect you need to give it since you have a lot of people who've never
welded before. It could be shortened up by not parroting what the video
tape says.

What I believe needs to happen is to have consistency between instructors,
as was I found the EAA welding forum to be next to worthless due to the
conflicting information. How is a newbie to differentiate between the
instructor who says do this, and then he moves on the hands on part and
they say don't do that. Your forum in my opinion created confusion in the
minds of some of the participants, or so I noticed when I was watching
them.

One of the most outstanding issues was if you attended any of the other
welding forums, Budd's or Kent's, what they did and said was not at all
what the EAA said. I'm not good enough to judge the correctness of what
the EAA instructors said, but I will do what people have been doing for a
very long time in contrast to what the EAA instructors said and as the
other two whom I respect have said.

On Tue, 02 Sep 2003 17:12:07 +0000, Richard Lamb wrote:


Acceptable to Whom?

The EAA I assume since they're the ones who made that claim.

I'll be
receiving my A&P this coming May

Del,

That's great newes. Did you manage to get a job at an airplane-fixing-place?

Bob

On Wed, 03 Sep 2003 13:03:03 -0500, "Matthew P. Cummings"
wrote:



I agree it's odd, and I won't be doing as the volunteer at the EAA welding
forum suggested because everything he said flies in the face of what the
rest of the world is doing. He was the guy who said to crack the valves.
I don't have an opinion one way or another on it, but the other guy said
to not crack it at all, and by that he meant a quick open and shutting of
the valve. He claimed that the Acetylene might blow up if you crack it
and the other problem was you released that gas in the shop you are going
to weld in. I can't disagree with that however.

Acettlene goes unstable when the pressure goes above something like
15? psi undisolved. It is stored disolved in Acetone. Cracking the
valve gently, and closing it gently, will NOT get free acetylene
anywhere close to the critical point, and will make sure you do not
get dirt into the regulator, which CAN cause the reg to stop
regulating, and put free acetylene over the critical pressure.

How much gas are you going to release?? The average welder likely
releases as much every time he lights his torch.

On 03 Sep 2003 04:47 PM, Bob Thomasson posted the following:
I'll be
receiving my A&P this coming May

Del,

That's great news. Did you manage to get a job at an airplane-fixing-
place?

No, I'm squandering my inheritance and going to school full time on the
accelerated version of the program here in Anchorage. With the credit
overload I am taking I don't think I could handle a job right now; last
semester I took 26, this semester I could only get 20 to fit in my
schedule but in the spring I go back up to 24 again. For all practical
purposes it is a full time 8 hour/day job except the cash flow is
inverted. 8^P

I'll most likely get a job at one of the local aviation fixit shops
until my brother and I can get our act together on building a hangar up
in the Mat/Su valley. Nice thing about Alaska is the way airplanes get
used (and used up) here there won't ever be any lack of business.

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First let me correct something in my post (there I go, reading my own
posts again). For filler I meant to say "ER70S-6, -3, or -2..."

Let me make a comment on your experience with the EAA forum. I am sorry
to hear that there was conflicting info given out at the forum. Yes,
there should be consensus between those instructing as to what basic
information will be conveyed.

Cracking a valve for a split second before mounting a regulator is
standard practice taught at all welding technical colleges and trade
schools whose curriculum I have seen. It clears trash, dust and bugs out
of the valve nozzle preventing then from entering and damaging the
regulator.

Let me make a point about why mild steel filler works and why you are
not sacrificing any strength. WHen welding with mild steel filler on
4130 there is ever so slight add-mixture taking place as some of the
alloying ingredients migrate in the molten puddle from the 4130 to the
mild steel filler. So the filler is a bit stronger and there is virally
no decrease in the strength of the tube. But, this really makes no
difference. If there were no add-mixture taking place the strength of
the weld would STILL exceed that of the tube.

Think about the fact that the tube you are welding usually has a wall
thickness of .065" or less...much less for the most part as most
fuselage tubes are in the range of .035" to .045". Even with TIG it is
not likely that you are going to make a welded bead (fillet)that is
smaller than 1/8" across the face. That makes the welded leg aprox.
..35". So under destructive load you have .35" worth of weld pulling
against .035" worth of tube wall. The failure is going to occur in the
tube. The mild steel may be ONLY 60,000 psi strength material while the
4130 tube is 100,000 psi, but for the amount of weld present, the weld
is many times stronger than the tube.

"Matthew P. Cummings" wrote:

On Wed, 03 Sep 2003 06:10:26 +0000, Bruce A. Frank wrote:

This is really getting some odd information presented here. The filler
rod intended for use with 4130 tube used to build a fuselage is MILD
STEEL. The weld is stronger than the tube even though welded with MILD

I agree it's odd, and I won't be doing as the volunteer at the EAA welding
forum suggested because everything he said flies in the face of what the
rest of the world is doing. He was the guy who said to crack the valves.
I don't have an opinion one way or another on it, but the other guy said
to not crack it at all, and by that he meant a quick open and shutting of
the valve. He claimed that the Acetylene might blow up if you crack it
and the other problem was you released that gas in the shop you are going
to weld in. I can't disagree with that however.

Honestly, I was very disappointed in the quality of the welding forum and
thought that if the EAA puts their name on it, then they should have some
sort of standardization to go with it. To me, it was a joke and not worth
the time spent there. How is a new user supposed to reconcile the polar
opposite information presented in one forum? That's why I didn't enjoy
the forum, one guy says do this, another says don't. One says use this
rod, the others say don't every use it unless it's in a motor mount. One
says stress relive, the other says that will CAUSE more problems than it
solves. In the end, everything I was taught about welding was said to be
wrong by the volunteer giving the presentation, yet, what I was taught is
what is still currently being taught and held as acceptable. If the
volunteer had facts to back him up it would have been nice, but take this
bit of information he presented. He claimed that why would you weld 4130
tubing and use something like mild steel for the filler thus causing the
4130 to loose tensile strength. So he said you MUST use 4130 in order to
retain the tensile strength of the tubing, ignoring the fact that the act
of welding lowers the strength. Based on his mistakes I did not learn
much since how can I trust an instructor when they present as fact
falsehoods? He also gave out smith numbers for the tips to use for
welding, but the problem was Smith does not use a number system like he
said, so a newbie would not know what to ask for because they would have
to find a compatible source. I.e. a 0 in one brand might not be a 0 in
another. How would a new user know there is no standardization in tip
sizes, especially when he said Smith has this number and they don't use
those numbers for the body he described?

If the EAA can't put on a unified front then they should not be involved
in teaching something like welding. They should take a page from other
groups which have a manual for the instructors, the instructors then go by
it and do not add their own information to it thus presenting a unified
classroom setting without causing confusion.

My desire would be for Budd to add a hands on to his presentation, he did
a respectable job getting the information across and did not have the
problem of giving conflicting information.

So, here's my plan. I'm using a rod like RG 45 for welding my 4130
tubing with my Smith AW1a torch.

--
Bruce A. Frank, Editor "Ford 3.8/4.2L Engine and V-6 STOL
Homebuilt Aircraft Newsletter"
| Publishing interesting material|
| on all aspects of alternative |
| engines and homebuilt aircraft.|
*------------------------------**----*
\(-o-)/ AIRCRAFT PROJECTS CO.
\___/ Manufacturing parts & pieces
/ \ for homebuilt aircraft,
0 0 TIG welding

While trying to find the time to finish mine.