Stainless tubing

[pojawis]

I'm looking for 2" stainless tubing for a tailpipe for a C-145-2. Anyone know where I can find it? I'm told it should be grade 341 or 321.

Thanks

[Jr.CubBuilder]

Wicks Aircraft Supply has some look under metals and then migrate to the stainless section.

http://www.wicksaircraft.com/

[DWood]

Wag Aero has extensions and they work very well.
Dan

[GAHorn]

I don't have my Wag Aero catalog with me and their online store isn't working so I cannot presently confirm my recollection/accuracy, but....
I seem to recall the Wag Aero extensions, although advertised for our engines/airframes...are actually unapproved. (They may have finally received approval for the actual pipes, but their installation onto our airplanes does not have a proper basis of approval.)
Additonally, one of the certification hoops a mfr has to jump thru is the overhang/moment of tailpipes to determine whether their additional length/weight will contribute to exhaust system cracking. (The extensions have such a reputation. Their additional length and weight presumeably magnafies the vibrations imparted to the exhaust system. They also add additonal drag to the airframe.)
Usually, the reason folks want the extensions is in order to minimize the exhaust soot on the lower cowl. Many original exhaust tailpipes are actually installed backwards which is a contributing factor to the deposits. It's been discussed here before in other discussion threads (use the search routine to find it),.... but the actual exit of original tailpipes should face the opening/cut forward and outward. It does NOT cause "backpressure" and decrease engine power. In fact, the (improper) reversal of the pipes to face the openings aft will actually contribute to the soot deposits because the exhaust exits in a (relatively) dead-air area and is thrown directly at the lower cowl. The correct, forward facing openings provide a boundary-layer of air between the exhausted gases and the lower cowl. See the Illustrated Parts Catalog (IPC) for the airplane to confirm the correct orientation of the exhaust tailpipes. (And I personally recommend against tailpipe extensions that are not approved for the aircraft by an STC, or another basis. While on that subject, the Benham and Bartone exhaust tailpipe modifications actually had STC basis of approval. The sellers of those mods, at last rumor, no longer would provide the STC paperwork for their installation, reportedly due to liability concerns. I personally can see no reason those mods would contribute to exhaust system cracking due to their installation instructions which included additional support for the longer tailpipes.....UNLIKE the Wag Aero type extensions which have no provision for additonal support...and hence their added risk of crack propagation.)

[dacker]

George, the extensions are FAA/PMA'd. I bought a set for my airplane and they had the little tag so stating. Now if Wag Aero has falsified this then that is another story. Strangely, even though they are supposed to be two inches longer, mine were not. I actually had to trim one because it was slightly longer (installed) than the other. They are not mirror images of each other, this makes sense considering the cylinder layout. I was just looking for new tail pipes, not necessarily the walrus fang look.
This is one of those instances where I would buy the FAA approved part then trim it to the original length, being careful to mimic the angle of the outlet. Please don't turn me in! If memory serves me correctly it basically took a compound cut to get it right.
David

[Roesbery]

Don't know if they are still there, or if they are what you want. But type in cessna exhaust in you know what website.

[GAHorn]

George, the extensions are FAA/PMA'd. I bought a set for my airplane and they had the little tag so stating. Now if Wag Aero has falsified this then that is another story. Strangely, even though they are supposed to be two inches longer, mine were not. I actually had to trim one because it was slightly longer (installed) than the other. They are not mirror images of each other, this makes sense considering the cylinder layout. I was just looking for new tail pipes, not necessarily the walrus fang look.
This is one of those instances where I would buy the FAA approved part then trim it to the original length, being careful to mimic the angle of the outlet. Please don't turn me in! If memory serves me correctly it basically took a compound cut to get it right.
David

You know...that's a curious thing. A PMA'd part is supposed to be an exact replacement part which mimics the original in every important respect. If that is not the case, ...then there should be another basis of approval...such as an STC. (For example, there can be a significant difference in the part design of the replacement part...an "improvement" perhaps....but due to that new part's difference....there must also be an STC or etc. to provide the basis for installation on a certificated type design. The holder of that STC may also have a PMA for the manufacture of the "improved" part to be installed under the STC. Otherwise, without additional basis, the part may not be different than the original. Does that help?
As for your alteration of the product....I'm sure you only provided the "final quality control and inspection" for your "owner-produced part".

[lowNslow]

Otherwise, without additional basis, the part may not be different than the original. Does that help?

The difference may be considered "minor" by the FAA and not require an STC. An example are the various cylinders sold for the O-200/O-300, these cylinders have minor differences from the original Continental cylinders. The only difference with these tailpipes is they are 2" longer than the originals, at best a 1 or 2 ounce difference in weight.