Prop touch-up

Tom-D said:
OkieFlyer is not qualified to blend a prop. He has no A&P near by, and some wonder why I say fly it to a prop shop and get it fixed.

This is what I love about internet trouble shooting, every body is an expert.
Even tho, they don't know at what magnifying rate that photo was taken. Yet they can determine it is not airworthy.

A&P-IA doing an annual are supposed to be determining airworthiness, So in their opinion it was, and said nothing. They actually saw it, and made a decision, I'll go with that.
FLY that sucker and go get it fixed.
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That includes the guy that claims chromic acid is neutral :)
 
Tom-D said:
Props are robust and much more sturdy than many give them credit for.
That prop is no worse Than many flying today. The last mechanic didn't believe it was a hazard, I'll go with that.
Those were new blades to start, and can have a huge amount of metal removed before they will be below blade profile.
If you look and compare the radius of the leading edge to the depth of these pits they appear to be less than 1/8" deep. I'll wager that a good prop shop will blend the leading edge alodine and send him on his way.
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Yes, props are robust. But they deserve to be looked after too. Just because one person didn't do anything doesn't mean all is well either. If you wish to hook your horse to someone else's poor judgement, go right ahead. I prefer to use my own professional judgement based on the information right in front of me.

In the end, the owner gets to make the final call, which is how it should be.
 
JAWS said:
Yes, props are robust. But they deserve to be looked after too. Just because one person didn't do anything doesn't mean all is well either. If you wish to hook your horse to someone else's poor judgement, go right ahead. I prefer to use my own professional judgement based on the information right in front of me.

In the end, the owner gets to make the final call, which is how it should be.
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If it matters at all, over the past 3 and a piece years I've owned it, 2 IAs and 3 A&Ps have laid hands on it at some point. None have felt the need to dress it thus far. Had I not had a few different guys see it, I would have done more before now. Having said that, I picked up that one significant ding recently that is my main concern. As far as depth is concerned, I might have one or two that are anywhere near 1/8th. Everything else is ugly, but shallow. There are ,however, a crap ton of shallow nicks covering a pretty large area. With the addition of the big one, it's time to do something about it. I will begin by running over to the A&P. I don't have one on the field, but there are some about 40 miles away. Didn't mean to say there weren't any around, just not handy at my airport.
 
Sorry, I might not have been clear. I was referring to to the IA's who have been signing off the annual as using poor judgement.
No way I could put my name to the prop in that condition at annual.
 
JAWS said:
Sorry, I might not have been clear. I was referring to to the IA's who have been signing off the annual as using poor judgement.
No way I could put my name to the prop in that condition at annual.
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That's just you.
Tell us what US rule you would use to prove it is unairworthy.
 
Tom-D said:
That's just you.
Tell us what US rule you would use to prove it is unairworthy.
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FAR 43 - Appendix D
Scope and Detail of Items to be Included in Annual and 100 Hour Inspections

...

(h) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the propeller group:

(1) Propeller assembly—for cracks, nicks, binds, and oil leakage.

(2) Bolts—for improper torquing and lack of safetying.

(3) Anti-icing devices—for improper operations and obvious defects.

(4) Control mechanisms—for improper operation, insecure mounting, and restricted travel.

 
JAWS said:
FAR 43 - Appendix D
Scope and Detail of Items to be Included in Annual and 100 Hour Inspections

...

(h) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the propeller group:

(1) Propeller assembly—for cracks, nicks, binds, and oil leakage.

(2) Bolts—for improper torquing and lack of safetying.

(3) Anti-icing devices—for improper operations and obvious defects.

(4) Control mechanisms—for improper operation, insecure mounting, and restricted travel.
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Is the inspector required to repair? Can the inspector decide if the defect needs to be repaired?
 
Cap'n Jack said:
Can the inspector provide a list of discrepancies?
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Certainly,, I often do, with instructions to get it repaired, lots of time I see stuff that should be fixed or replaced, but are not an airworthy issue.
 
Tom-D said:
Certainly,, I often do, with instructions to get it repaired, lots of time I see stuff that should be fixed or replaced, but are not an airworthy issue.
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If the inspector felt the prop needed dressing, another repair, or replacement, would that be in the list too?
 
Cap'n Jack said:
If the inspector felt the prop needed dressing, another repair, or replacement, would that be in the list too?
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Could be, but keep in mind the OP has stated the big nick wasn't there at last annual. So we don't know what the condition was at that time. JAWs seems to want to blame the IA for derelict of duty, when we don't really know what he saw at the time.
 
Tom-D said:
Could be, but keep in mind the OP has stated the big nick wasn't there at last annual. So we don't know what the condition was at that time. JAWs seems to want to blame the IA for derelict of duty, when we don't really know what he saw at the time.
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JAWS response could have been interpreted a couple of ways, I thought he meant as prior to the large nick. But he can answer for himself.
 
Post 126. Is why I made the comment
 
Tom-D said:
Post 126. Is why I made the comment
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So was I. I figured he wouldn't hold an inspector responsible for something that happened after the inspection as it would be illogical to do so. I did mention that I thought his response was meant to be before the large nick.

But he can answer for himself what he actually meant.
 
Cap'n Jack said:
So was I. I figured he wouldn't hold an inspector responsible for something that happened after the inspection as it would be illogical to do so. I did mention that I thought his response was meant to be before the large nick.

But he can answer for himself what he actually meant.
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Now this thread has become a who said what when why. I thing I'm gone.
The OP has had all the guidance he needs.
 
That amount of damage doesn't happen over one flight. The OP has even said that it has gone an annual or two with the damage not touched or mentioned.
To let anything close to what was shown go thru an annual and get certified, sorry but that is wrong.

Do I know the whole story? Nope. Just going off the information being given. The thread is titled "Prop Touch Up" and originally centered around touching up the face paint. Now the pictures show pretty good nicks and erosion.
The prop isn't falling off, but it does need work. How much or how little, that is yet to be determined. The owner is in control of what and when things get done. The maintainer decides the how.

I gave my evaluation using the information given at the time. That is the best I can do over the internet.
 
Yep. I'll get it looked at and hopefully blended out before painting. I still needed to know whether I can paint it myself or not once repaired. As mentioned, the big ding and probably a few of the smaller ones have happened over the last several months since annual. Much of the other stuff was there and not deemed detrimental enough to bust out the file. Right or wrong, that was the judgment made. I've got what I need and I appreciate all the info.
 
Cap'n Jack said:
Starting at post 133, you chose to take it down that path.
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Yep, it is called thread creep, where by people get their questions answered and you've joined in.

SO.... ?
 
Tom-D said:
Yep, it is called thread creep, where by people get their questions answered and you've joined in.

SO.... ?
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So, don't complain when the thread continues down a path you started. If you want the thread back on track a little, please explain how chromic acid has a neutral pH at the concentration used for chromium conversion.
 
OkieFlyer said:
Yep. I'll get it looked at and hopefully blended out before painting. I still needed to know whether I can paint it myself or not once repaired. As mentioned, the big ding and probably a few of the smaller ones have happened over the last several months since annual. Much of the other stuff was there and not deemed detrimental enough to bust out the file. Right or wrong, that was the judgment made. I've got what I need and I appreciate all the info.
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That is good to hear. Good luck.
 
Cap'n Jack said:
So, don't complain when the thread continues down a path you started. If you want the thread back on track a little, please explain how chromic acid has a neutral pH at the concentration used for chromium conversion.
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Start a new thread and we will get a chemist to tell us.
 
Cap'n Jack said:
So, don't complain when the thread continues down a path you started. If you want the thread back on track a little, please explain how chromic acid has a neutral pH at the concentration used for chromium conversion.
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Why did you draw the conclusion I was complaining ?
 
OkieFlyer said:
I still needed to know whether I can paint it myself or not once repaired.
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In the strictest reading of the FARs - no, painting of the prop is maintenance, and requires a properly rated person to do it and return it to service.

This is why I advised you to take it to a prop shop. They will properly repair and refinish the prop. Then you know it was done correctly.
 
Tom-D said:
In the strictest reading of the FARs - no, painting of the prop is maintenance, and requires a properly rated person to do it and return it to service.
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And all of the other items in the appendix are not maintenance items? :rolleyes:

To the OP, I believe you can legally touch up the prop paint. But your prop needs work that is beyond owner maintenance. Let a proper mechanic evaluate your prop damage and (hopefully) be able to dress the damage out of it, alodine and touch up the paint. If, in the future, you want to touch up the paint (assuming no other damage), then have at it.

If you aren't interested in following the regs, do whatever you like.
 
JAWS said:
And all of the other items in the appendix are not maintenance items? :rolleyes:
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Maybe you should explain the difference between "Preventive maintenance" and another maintenance done on aircraft, and just why Props are never mentioned in FAR 43-A (c ) 1-31
 
Cap'n Jack said:
Because you brought it up.
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Oh so now anytime I mention something I'm complaining ?

I believe you should brush the chip off your shoulder and read what I write with out the bias.
 
Cap'n Jack said:
You said it was neutral pH...you explain it. I highly doubt you would get a chemist to agree with you.
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Agree or not that is what the recipe is, And that came from the AMS 3&2 Structural mechanic training manual, where they teach all structural mechanics in the NAVY how to make it Alodine from Chromic crystal.

You asked WHY? ask a Chemist, not me I just know how, not why.
 
Tom-D said:
Agree or not that is what the recipe is, And that came from the AMS 3&2 Structural mechanic training manual, where they teach all structural mechanics in the NAVY how to make it Alodine from Chromic crystal.

You asked WHY? ask a Chemist, not me I just know how, not why.
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Tom....you don't get it do you? Chromic acid is....acidic. Not neutral. You just did ask a chemist.

Tom-D said:
Oh so now anytime I mention something I'm complaining ?

I believe you should brush the chip off your shoulder and read what I write with out the bias.
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I don't suppose you noticed I asked a question in your other thread about "Another Pandoria's box" [sic]. My impression is you were the one with the chip here in this thread. I do read your posts, but when you claim that something that is dissolved in mineral oil is difficult to remove with a simple solvent such as turpentine (posts 30 & 82 this thread), that is incorrect information. I suggest you also look at the references provided in post #84 that describe the chromium conversion process; the chemistry is different from your description in post 81. You may consider that other people are correct too.
 
Cap'n Jack said:
It's not just a different opinion or his condescension. He makes posts beyond his knowledge and continues to assert his own set of facts even when they are shown to be wrong. The problem is that someone asking for help doesn't know where his knowledge ends and where the BS begins which can lead to a bad decision. I question whether he actually does know more about it. I agree with you about the price in messing it up.
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My knowledge comes from experience, And I know that when aluminum has been coated with oil of any kind it requires much more than turpentine to get alodine to do what it is required to do, and to add paint over paint that has a contaminate in it, is never been advised by any painter.
I'll learn that Alodine is an acid and can't be neutral PH, But what I was taught many years ago by those I respected stays with me.
To add, the advice I've given on how to deal with this prop, Is directly from dealing with props and prop shops almost daily and how to get the best for your dollar.
If you like you do as you please, but remember one of us is an A&P-IA the other a chemist.
 
Cap'n Jack said:
Tom....you don't get it do you? Chromic acid is....acidic. Not neutral. You just did ask a chemist.
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I do get that ,,, now
But please explain how turpentine will leave a clean enough surface to apply alodine?

You might also want to know that you have been on ignore until early today, might explain why you didn't get answers.

Now I think I'll put on ignore again.
 
OkieFlyer said:
Yeah, yeah. Tail dragger guys :rolleyes:

Do you have any idea how much people want for them things? ;)
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I have a 182 customer that operates off a river gravel bar, he hasn't a single ding in over 4 years.
want to know why? he never goes above idle until he is moving.
 
So, given what you have seen, what kind of money are we talking about if I take it to a prop shop? I understand you can't know exactly, but I don't know if I should expect $500 or $5000. First time.

Tom-D said:
I have a 182 customer that operates off a river gravel bar, he hasn't a single ding in over 4 years.
want to know why? he never goes above idle until he is moving.
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Heck I operate off of 3000' of good asphalt. The hangar apron has deteriorated into about 50% gravel over the years. I usually warm up for a minute at about 800 RPM and then roll over to the good asphalt without adding power to finish warming up. I do have to add a little bump of power to get up on the taxiway since there is a pretty good hump, but it's momentary. Also have to give a little nudge of power when I park to get lined up to back it in the hangar. I dunno, maybe I just suck.
 
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