Paint Stripping

Cap'n Jack said:
One other thing, @Tom-D

Please don't change quotes on people. It is, at a minimum, extremely rude. It makes the person changing the quote appear to be a liar when they are caught. I didn't write the text highlighted below.
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Here is an image of my original post- as can be seen, it is unedited so one can't claim that I changed the post to make you look bad
View attachment 51997
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That was not meant to change your quote, simply to point out a different part of the link.
 
Cap'n Jack said:
Tom- I know you don't care what I, or anyone else thinks of you. However, you make yourself out to be a poor mechanic when you:
-Confuse acids and bases. This is taught in high school, nevermind the Navy
-Spell the element "zinc" as "zink"
-Pretend you know more than you actually do

If someone asked to to recommend a mechanic at Oak Harbor airport, I frankly, based on how you present yourself here, would tell them to avoid you at all costs.
Further, incidents such as that listed here don't help you at all:
https://www.ntsb.gov/investigations...ev_id=20150928X72825&ntsbno=WPR15FA268&akey=1


Other people read these posts and discussions as well and they really don't reflect well on you.
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Please read the AC 43,13 chapter 6.

6-3. COMMON CORROSIVE AGENTS.

Substances that cause corrosion are called corrosive agents. The most common corrosive agents are acids, alkalies, and salts. The at- mosphere and water, the two most common media for these agents, may also act as corrosive agents.

This has been the Bible for General aviation corrosion prevention and treatment for as long as I can remember, And its policies haven't change just because we have new products on the market. These new strippers may be a lessor hazard to us and the environment than those we used prior but they are a corrosive agent just the same. When misused they will cause just as much damage as the ones we used prior.
 
When I did my airplane, I used a stripper from PPG. Following the TDS, there is no need for an "acid etch", or Alodine.
Just apply the stripper, let it work, agitate with red scotchbrite, wash off with soap and water. When clean and dry, apply the conversion coat.
Allow it to dry, then prime(optional) and paint.
TDS for the stripper: http://www.ppgaerospace.com/getmedi...f77b2/PR-3500-PB-PPG-FORMAT.pdf.aspx?ext=.pdf
TDS for conversion coat: http://www.ppgaerospace.com/getmedi...d93e3647ca88/desogel_eap-12.pdf.aspx?ext=.pdf
TDS for the soap that I used: http://www.ppgaerospace.com/getmedi...500_Alkaline_Water_Based_Cleaner.pdf?ext=.pdf
 
Tom-D said:
Please read the AC 43,13 chapter 6.

6-3. COMMON CORROSIVE AGENTS.

Substances that cause corrosion are called corrosive agents. The most common corrosive agents are acids, alkalies, and salts. The at- mosphere and water, the two most common media for these agents, may also act as corrosive agents.

This has been the Bible for General aviation corrosion prevention and treatment for as long as I can remember, And its policies haven't change just because we have new products on the market. These new strippers may be a lessor hazard to us and the environment than those we used prior but they are a corrosive agent just the same. When misused they will cause just as much damage as the ones we used prior.
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What does this have to do with the points that you replied to?
When you post something that is wrong, and then double-down on it, it causes me, and others, to wonder what else you don't know within your field.

Here they are again again:
Cap'n Jack said:
Tom- I know you don't care what I, or anyone else thinks of you. However, you make yourself out to be a poor mechanic when you:
-Confuse acids and bases. This is taught in high school, nevermind the Navy
-Spell the element "zinc" as "zink"
-Pretend you know more than you actually do

If someone asked to to recommend a mechanic at Oak Harbor airport, I frankly, based on how you present yourself here, would tell them to avoid you at all costs.
Further, incidents such as that listed here don't help you at all:
https://www.ntsb.gov/investigations...ev_id=20150928X72825&ntsbno=WPR15FA268&akey=1


Other people read these posts and discussions as well and they really don't reflect well on you.
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Cap'n Jack said:
What does this have to do with the points that you replied to?
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Does it really matter if it is an acid or a SALT that causes the corrosion? Is a missed quote is a really a big thing with you?

My whole point was with the pressure washing. You remove any and all protection with a stripper, then blow what ever is on the surface into the seams. you then you worry about my mis-quote. WTF really what is the priority ?
 
Ok, Tom-D rather than arguing semantics of what causes corrosion and what is corrosive....

How about giving us your opinion on how to properly remove paint stripper from an airplane? I am curious how to really do it? My guess is chemical strippers and power washing are the way it is done, but I really don't know. You seem to be knowledgeable but like to really split hairs on asinine topics.
 
Tom-D said:
Does it really matter if it is an acid or a SALT that causes the corrosion? Is a missed quote is a really a big thing with you?

My whole point was with the pressure washing. You remove any and all protection with a stripper, then blow what ever is on the surface into the seams. you then you worry about my mis-quote. WTF really what is the priority ?
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Yes, it does matter. The corrosion mechanisms of acids, bases, and salts are different. Not all salts are bad- This PPG product, paint stripper, (http://www.ppgaerospace.com/getmedi...f77b2/PR-3500-PB-PPG-FORMAT.pdf.aspx?ext=.pdf) is apparently designed for aircraft, and contains sodium chromate, and is actually a corrosion inhibitor. Sodium chromate is one of many salts and they all have different properties.

By posting information that isn't true, you call into question your knowledge as a mechanic. Some of this is very basic information- "zinc" vs "zink" as you allow zinc is a component of solders for aluminum (https://www.pilotsofamerica.com/community/threads/oil-filler-door-repair.99540/page-3) and also zinc chromate coating on metals. The name of a metal is very basic A&P and metal-smith knowledge, the most basic knowledge.

If I posted something like "when converting a plane to operate on floats, the original control cables are fine", you would, correctly, question my knowledge. (My understanding is that stainless steel control cables should be used in such a situation). When you call a basic compound an acid, I and others likewise question your knowledge. When you post here, I'd hope that you would teach us stuff. However, there is no teaching if the teacher doesn't know what they are talking about, or they mix good knowledge with bad information as your posts often do.
 
GlennAB1 said:
Not to nit-pick, but, are they actually stainless steel cables, or are they corrosion resistant steel (CRES)?
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I don't really know, and you are demonstrating my point.
I use this board in part for information- I'm not an A&P, but I realize they do things in a certain fashion and use various materials for good reason. If I were to build a plane or do owner-assisted repairs, I would want to follow the best practices, and this board is one source of information (along with the advisory circulars, repair books, product instructions, and so forth). Even if I had a factory-built plane, I'd like to know if the repair(s) are being done correctly. The internet (and this board) are potentially useful places to get information but both lose their usefulness when people who only think they know a subject reply to questions. One way to filter out the BS from the good information is the consistency of the data. When someone spells the name of a metal as "zink", claims ammonia is an acid, claims an -NH2 primary amine group to be an amide (and ionized too), that information is contrary to what I know and makes me wonder if the rest of what they posted was pulled from their butt.

I also realize there may be more than one correct way to do something (could stainless steel cables or CRES cables be both acceptable? Is one better than the other in certain circumstances?). You saw from my reply I probably didn't fully understand what I was talking about and were right to question it. I won't argue about it nor call you Professor gobble gook for the correction. Now I'll ask- what is the proper material in such an application?
 
Cap'n Jack said:
I don't really know, and you are demonstrating my point.
I use this board in part for information- I'm not an A&P, but I realize they do things in a certain fashion and use various materials for good reason. If I were to build a plane or do owner-assisted repairs, I would want to follow the best practices, and this board is one source of information (along with the advisory circulars, repair books, product instructions, and so forth). Even if I had a factory-built plane, I'd like to know if the repair(s) are being done correctly. The internet (and this board) are potentially useful places to get information but both lose their usefulness when people who only think they know a subject reply to questions. One way to filter out the BS from the good information is the consistency of the data. When someone spells the name of a metal as "zink", claims ammonia is an acid, claims an -NH2 primary amine group to be an amide (and ionized too), that information is contrary to what I know and makes me wonder if the rest of what they posted was pulled from their butt.

I also realize there may be more than one correct way to do something (could stainless steel cables or CRES cables be both acceptable? Is one better than the other in certain circumstances?). You saw from my reply I probably didn't fully understand what I was talking about and were right to question it. I won't argue about it nor call you Professor gobble gook for the correction. Now I'll ask- what is the proper material in such an application?
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If you were to NOT follow the float kit manufacturer's instructions and use unauthorized parts of course I'd catch it on the annual or the sign off to return to service.
That is what inspectors do.
But when the cables are part of an authorized modification, I'd require you to prove it with the proper paper work. That is the portion of "or Properly altered condition" of the Airworthiness statement.
I normally do not make the distinction between Corrosion causing agents such as acids and salts, even if there are benign types in the mix, simply because it would be confusing. The 43,13 is the guide and it makes no distinction either.
 
GlennAB1 said:
Not to nit-pick, but, are they actually stainless steel cables, or are they corrosion resistant steel (CRES)?
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That's solely up to the float kit manufacturer. I can't think of any that aren't.
 
I guess by your comments you've never run a power washer. It can be done the right way.
Tom-D said:
Does it really matter if it is an acid or a SALT that causes the corrosion? Is a missed quote is a really a big thing with you?

My whole point was with the pressure washing. You remove any and all protection with a stripper, then blow what ever is on the surface into the seams. you then you worry about my mis-quote. WTF really what is the priority ?
Click to expand...
 
Tom-D said:
If you were to NOT follow the float kit manufacturer's instructions and use unauthorized parts of course I'd catch it on the annual or the sign off to return to service.
That is what inspectors do.
But when the cables are part of an authorized modification, I'd require you to prove it with the proper paper work. That is the portion of "or Properly altered condition" of the Airworthiness statement.
I normally do not make the distinction between Corrosion causing agents such as acids and salts, even if there are benign types in the mix, simply because it would be confusing. The 43,13 is the guide and it makes no distinction either.
Click to expand...

With the comment below, you certainly found the difference between acids and ammonia (a base) confusing...
Tom-D said:
Yeah let's drive those acids into the rivet seams, we metal smiths love you for that.
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Looking at AC 43.13 (https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_43.13-1B_w-chg1.pdf)
Page 6.2 does make a distinction between acids (6.3.a) and bases (6.3.b and you probably missed this part because it is titled "Alkalies", not bases), so you missed that as well.

Again, talking about stuff for which you have no knowledge
 
Cap'n Jack said:
I don't really know, and you are demonstrating my point.
I use this board in part for information- I'm not an A&P, but I realize they do things in a certain fashion and use various materials for good reason. If I were to build a plane or do owner-assisted repairs, I would want to follow the best practices, and this board is one source of information (along with the advisory circulars, repair books, product instructions, and so forth). Even if I had a factory-built plane, I'd like to know if the repair(s) are being done correctly. The internet (and this board) are potentially useful places to get information but both lose their usefulness when people who only think they know a subject reply to questions. One way to filter out the BS from the good information is the consistency of the data. When someone spells the name of a metal as "zink", claims ammonia is an acid, claims an -NH2 primary amine group to be an amide (and ionized too), that information is contrary to what I know and makes me wonder if the rest of what they posted was pulled from their butt.

I also realize there may be more than one correct way to do something (could stainless steel cables or CRES cables be both acceptable? Is one better than the other in certain circumstances?). You saw from my reply I probably didn't fully understand what I was talking about and were right to question it. I won't argue about it nor call you Professor gobble gook for the correction. Now I'll ask- what is the proper material in such an application?
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"Corrosion resistance steel" is a range of alloy steels of varying corrosion resistance and other characteristics, which "Stainless" falls into. I've never heard of "Stainless steel" aircraft control cables, just CRES. I'm not sure "stainless" varieties meet aircraft cable requirements.

Generally speaking, people assume Stainless steel won't rust. One example: There's a group of people that paid a lot of money for "stainless steel" gas grills only to be very disappointed year or two later. There are several discussions about it on the www.
 
GlennAB1 said:
"Corrosion resistance steel" is a range of alloy steels of varying corrosion resistance and other characteristics, which "Stainless" falls into. I've never heard of "Stainless steel" aircraft control cables, just CRES. I'm not sure "stainless" varieties meet aircraft cable requirements.

Generally speaking, people assume Stainless steel won't rust. One example: There's a group of people that paid a lot of money for "stainless steel" gas grills only to be very disappointed year or two later. There are several discussions about it on the www.
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Actually they are what is known as "NI-Chrome", it is a 9% chrome steel.
 
bluerooster said:
When I did my airplane, I used a stripper from PPG. Following the TDS, there is no need for an "acid etch", or Alodine.
Just apply the stripper, let it work, agitate with red scotchbrite, wash off with soap and water. When clean and dry, apply the conversion coat.
Allow it to dry, then prime(optional) and paint.
TDS for the stripper: http://www.ppgaerospace.com/getmedi...f77b2/PR-3500-PB-PPG-FORMAT.pdf.aspx?ext=.pdf
TDS for conversion coat: http://www.ppgaerospace.com/getmedi...d93e3647ca88/desogel_eap-12.pdf.aspx?ext=.pdf
TDS for the soap that I used: http://www.ppgaerospace.com/getmedi...500_Alkaline_Water_Based_Cleaner.pdf?ext=.pdf
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Skimming thru your product links Your stripper is known as a Jellied Acetone, generically.
the treatments are classed as etches.
there are lots of products out there so read carefully. None of them are good for you.
 
GlennAB1 said:
Tom is absolutely correct about pressure washers, they can be an aircrafts worst enemy.
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Folks don't realize that a pressure washer even the lower pressure ones will separate the skins and blow the chemicals into the inner portion of the wings and such and that debris will not be found or treated until its too late.
 
Cap'n Jack said:
Again, talking about stuff for which you have no knowledge
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Did you miss para 6-3 is the lists of corrosive agents.
In case you'd like to read it again.

6-3. COMMON CORROSIVE AGENTS.

Substances that cause corrosion are called cor rosive agents. The most common corrosive agents are acids, alkalies, and salts. The at mosphere and water, the two most common media for these agents, may also act as corro sive agents.

a. Any acid will severely corrode most of the alloys used in airframes. The most destructive are sulfuric acid (battery acid), halo gen acids (hydrochloric, hydrofluoric, and hy drobromic), nitrous oxide compounds, and or ganic acids found in the wastes of humans and animals.

b. Alkalies, as a group, are not as corro sive as acids. Aluminum and magnesium al loys are exceedingly prone to corrosive attack by many alkaline solutions unless the solutions contain a corrosion inhibitor. Substances par ticularly corrosive to aluminum are washing soda, potash (wood ashes), and lime (cement dust).

c. The major atmospheric corrosive agents are oxygen and airborne moisture. Corrosion often results from the direct action of atmospheric oxygen and moisture on metal nd the presence of additional moisture often accelerates corrosive attack, particularly on ferrous alloys. The atmosphere may also con tain other corrosive gases and contaminants, particularly industrial and marine salt spray.

d. The corrosiveness of water depends on the type and quantity of dissolved mineral and organic impurities and dissolved gasses (particularly oxygen) in the water. One char acteristic of water that makes it corrosive is its conductivity. Physical factors, such as water temperature and velocity also have a direct bearing on its corrosiveness.

Just because some SALTs are benign, doesn't make it ok to leave them in a seam.
 
Full disclosure....I wash my Bonanza with a power washer....and it's still airworthy. :confused:
 

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Tom-D said:
Did you miss para 6-3 is the lists of corrosive agents.
In case you'd like to read it again.

6-3. COMMON CORROSIVE AGENTS.

Substances that cause corrosion are called cor rosive agents. The most common corrosive agents are acids, alkalies, and salts. The at mosphere and water, the two most common media for these agents, may also act as corro sive agents.

a. Any acid will severely corrode most of the alloys used in airframes. The most destructive are sulfuric acid (battery acid), halo gen acids (hydrochloric, hydrofluoric, and hy drobromic), nitrous oxide compounds, and or ganic acids found in the wastes of humans and animals.

b. Alkalies, as a group, are not as corro sive as acids. Aluminum and magnesium al loys are exceedingly prone to corrosive attack by many alkaline solutions unless the solutions contain a corrosion inhibitor. Substances par ticularly corrosive to aluminum are washing soda, potash (wood ashes), and lime (cement dust).

c. The major atmospheric corrosive agents are oxygen and airborne moisture. Corrosion often results from the direct action of atmospheric oxygen and moisture on metal nd the presence of additional moisture often accelerates corrosive attack, particularly on ferrous alloys. The atmosphere may also con tain other corrosive gases and contaminants, particularly industrial and marine salt spray.

d. The corrosiveness of water depends on the type and quantity of dissolved mineral and organic impurities and dissolved gasses (particularly oxygen) in the water. One char acteristic of water that makes it corrosive is its conductivity. Physical factors, such as water temperature and velocity also have a direct bearing on its corrosiveness.

Just because some SALTs are benign, doesn't make it ok to leave them in a seam.
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@Tom-D

You are contradicting yourself again. The citation above is the same one I cited, para 6.3. You just proved the same thing I did, that AC43.13 does make such a distinction.
Note the bolded text below that you typed :
Tom-D said:
If you were to NOT follow the float kit manufacturer's instructions and use unauthorized parts of course I'd catch it on the annual or the sign off to return to service.
That is what inspectors do.
But when the cables are part of an authorized modification, I'd require you to prove it with the proper paper work. That is the portion of "or Properly altered condition" of the Airworthiness statement.
I normally do not make the distinction between Corrosion causing agents such as acids and salts, even if there are benign types in the mix, simply because it would be confusing. The 43,13 is the guide and it makes no distinction either.
Click to expand...

Again, you typed mis-information, and this time you are trying to walk it back as if I typed the wrong thing.
 
Tom-D said:
I said it was a generic term. reading to pick a nit are we?
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The difference between acetone and a mixture of phenol and dichloromethane is much more than a nit. Acetone is very different than dichloromethane and the health hazards are very different as well.

Again, @Tom-D is giving bad advice and wrong information
 
Cap'n Jack said:
@Tom-D

You are contradicting yourself again. The citation above is the same one I cited, para 6.3. You just proved the same thing I did, that AC43.13 does make such a distinction.
Note the bolded text below that you typed :


Again, you typed mis-information, and this time you are trying to walk it back as if I typed the wrong thing.
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He does that!
 
Cap'n Jack said:
The difference between acetone and a mixture of phenol and dichloromethane is much more than a nit. Acetone is very different than dichloromethane and the health hazards are very different as well.

Again, @Tom-D is giving bad advice and wrong information
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Tell us how you know what the guys in the field call any of these chemicals?
 
Yeah, it could just all be
Tom-D said:
Actually they are what is known as "NI-Chrome", it is a 9% chrome steel.
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I'll take your word on that. I don't know of any reason a mechanic would need to know that. The cable we get in bulk is either corrosion resistant steel or carbon steel, prestretched or not. Occasionally, when mechanics are doing cable corrosion control/lubrication they will come to me with a question. The Boeing maintenance manual specifies to only lubricate carbon steel cables, how can he determine if the cables are CRES or carbon steel? What would you say?
 
GlennAB1 said:
Yeah, it could just all be

I'll take your word on that. I don't know of any reason a mechanic would need to know that. The cable we get in bulk is either corrosion resistant steel or carbon steel, prestretched or not. Occasionally, when mechanics are doing cable corrosion control/lubrication they will come to me with a question. The Boeing maintenance manual specifies to only lubricate carbon steel cables, how can he determine if the cables are CRES or carbon steel? What would you say?
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First and easiest. stick a magnet on it. most SS cables it won't stick.
Some will. so the P/N is the real test.
 
GlennAB1 said:
Wrong. That's why Boeing has an eddy current procedure for making the determination.
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Is Boeing going to come out and do the determination for the public? You stated you have procedures, then use them.
When I must figure out what stuff is, I don't have Boeing capabilities. I do have a magnet.
 
Getonit said:
Ok, Tom-D rather than arguing semantics of what causes corrosion and what is corrosive....

How about giving us your opinion on how to properly remove paint stripper from an airplane? I am curious how to really do it? My guess is chemical strippers and power washing are the way it is done, but I really don't know. You seem to be knowledgeable but like to really split hairs on asinine topics.
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RE-read post #3.
 
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