Old Sheet Metal Cross Reference

[AVPacer]

I’m repairing a flap on my 1959 PA-22/20 and I'm trying to identify the kind of aluminum piper used. I know the industry changed the way they identified sheet aluminum alloys from a 2 digit identifier to a 4 digit identifier somewhere along the way. I’m looking for a cross reference of some kind that would help me translate the old identification to the newer alloy identification.

The only markings I can make out on the original part are;

3S

H14 (hardness)

24S-1

.02 (thickness)

Daryl

[Tlb67]

I’m repairing a flap on my 1959 PA-22/20 and I'm trying to identify the kind of aluminum piper used. I know the industry changed the way they identified sheet aluminum alloys from a 2 digit identifier to a 4 digit identifier somewhere along the way. I’m looking for a cross reference of some kind that would help me translate the old identification to the newer alloy identification.

The only markings I can make out on the original part are;

3S

H14 (hardness)

24S-1

.02 (thickness)

Daryl

2024 t3 is what you need . thats the closest to what was used during and just after ww2 not sure when they changed the numbers

[turtle]

3003-H14 is what was used for the leading and trailing edges. 2024-T3 for the spar and ribs.

The old Aircraft Spruce catalogs used to have a chart.

[steveinindy]

Here's the chart Turtle referred to: http://www.aircraftspruce.com/catalo...s/aluminfo.php (Scroll down).

As Turtle said, 3003 is the equivalent of 3S apparently. I learned something I didn't know previously as a result of the search that turned that up

[nrpetersen]

3003H14 is pretty soft stuff when compared to 2024T3 which feels more like a clockspring. Considering that the harder material drills and cuts better & is a lot stronger, you may want to just use 2024T3. It does cost a little more but those cauliflowered leading edges you see on Cubs are pretty much due to the use of 3003H14.

[turtle]

I'd use what Piper used. In most cases when someone made a part with a "better" grade, it didn't last as long as the original due to things like cracking.

Mr. Piper was almost as smart as he was cheap.

[WLIU]

Actually, 2024T3 is pretty much approved by the FAA to replace the older grades of aluminum used in most aircraft, including Pipers. 7075 and some other less common grades excepted. Give AC43.13 a read. For a flap, 2024 is certainly the preferred material.

I will agree that Mr. Piper was cheap.

Best of luck,

Wes
N78PS