The typo is this: Filler Rod per ER70-S2 and should be
            this: Filler Rod per ER70S-2.  Supposedly.

Therefore new questions are:

1)  Is this AMS or AWS or who's spec?
2)  Is filler metal called out or referenced in AMS-STD-
    219?  

Jesus is THE life,
Leonard

Although there are several good filler materials, ER80S-D2, is one you should consider. This filler material is capable of producing welds that approximate the strength of 4130. ER-70S-2 is an acceptable alternative to ER80S-D2, as is ER70S-6, although the weld strength will be slightly lower.

ER80S-D2  

E stands for "Electrode"
R stands for "Rod"
The first two or three numbers are an abbreviation of the weld's strength. To figure out the strength of the weld, take the 2 digits, in this case 80, and multiply by 1000 to get the weld strength in PSI.
S stands for solid electrode or rod.

If there is a letter and number combination next, it relates to the chemical composition of the weld deposit.
(NONE)--Mild Steel
A1---Carbon Moly
B1---1/2 CR, 1/2 MO
B2---1-1/4 CR, 1/2 MO
B3---1-1/4 CR, 1 MO
C1---2-1/2 Nickel
C2---3-1/2 Nickel
C3---1 Nickel
D1---1-1/2 MN, 1/4 MO
D2---1.25-2% MN, 0.25-0.45% MO
G---Alloy not designated
M---conforms to military specs.

For parts thicker than .120", stress-relieving is recommended and 1,100ºF is the optimum temperature for tubing applications.

boo1,
Thanks loads that helps my memory graetly.

Can you answer the following:

Therefore new questions are:

1)  Is this AMS or AWS or who's spec?
2)  Is filler metal called out or referenced in AMS-STD-
    219?   

Jesus is THE life,
Leonard

1. This is AWS nomenclature.
2. MIL-STD-2219 does not have a requirement for "x" filler rod to be used with "y" steel grade.  I seriously doubt that AMS-STD-2219 does either.

FYI,
It looks like DoD handed the ball (MIL-STD-2219) off to SAE and now SAE fumbled it. From the SAE website:

AMSSTD2219 : Fusion Welding for Aerospace Applications (Cancelled Sep 2002) 09-04-2002 Standard
 The purpose of this document is to provide minimum requirements for weld filler materials, workmanship, inspection and record requirements for fusion welding of alloys applicable to aircraft, missiles, other aerospace equipment, their parts and accessories.
 
Also cancelled:  AMSSTD1595 : Qualification of Aircraft, Missile and Aerospace Fusion Welders (Cancelled Sep 2002) 09-04-2002 Standard
 This standard establishes the procedure for qualification of welders and welding operators engaged in the welding of aircraft, missiles, other aerospace equipment, and their parts and accessories by fusion welding processes. This standard is applicable to aircraft, missile, and aerospace ground support equipment or other welding, when included in the contracting documents or when invoked in the absence of a specified welder qualification document.  

Anyone needing the specs. MIL-STD-2219 and MIL-STD-1595A should download them before they disappear from the ASSIST site (http://assist2.daps.dla.mil/quicksearch/).

Hello! metman
I think u can use ER70S3 filler rod without any fear. This is an AWS specified electrode.
Good bye.
Farigh

ER70S-2 is AWS A5.18 CLASSIFICATION