HELP! Need corrosion chemist...

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RT Firefly

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Greetings,
Our "new" boat was used in salt water and the aluminum window tracks are corroded where the fuzzy track strips slide into place. Slide is the operative word here. The grooves that accept the fuzzy are visible but quite inaccessible to mechanical scouring/scraping and are very small (in the order of .080").

There is a rock hard deposit of what tastes like salt but is probably an aluminum oxide/aluminum chloride mixture built up in the grooves. As mentioned, mechanical removal is almost impossible so I'm searching for the chemical which will actually dissolve or at least significantly soften the deposits.

I've tried sulfuric, hydrochloric acids and Starbright "Salt-away" with seemingly no reaction other than the HCl reacting with the Al. I can live with losing a bit of the Al IF it means easy removal of the deposits.

So, is there something that will dissolve/soften this mess so I can be fuzzy again?

Thanks in advance.
 
The aluminum oxide you are trying to get off is about as susceptible to corrosion from something like hydrochloric acid as the underlying aluminum. Think about it, the reason unpainted aluminum doesn't corrode is a thin film of aluminum oxide that quickly forms on its surface.


You have already tried the most likely candidate: hydrochloric acid and discovered that it attacks the aluminum almost as well as the deposit. I am afraid you are going to have to scrape or replace.


David
 
Greetings,
Mr. dj. Yup, HCl will attack the Al as evidenced by the vibrant reaction on a bare spot BUT it did not appear to react with the "deposit" (no bubbling visible with eye magnification). I understand the Al oxide protective layer scenario but replacement of the widow is out of the question and as I mentioned, scraping is nigh on next to impossible.

Since the two acids I tried do not seem to work, I might try a strong base (Easy Off oven cleaner or a straight lye solution). I do have access to glacial acetic and percloric (conc) acids so that may be next before the base...Thanks. Hydrogen peroxide perhaps?
 
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Can you use a dremel and a large metal reinforced cutoff wheel and grind that away?
I have cut off wheel of almost 1.5 inch diameter. And have used these to grind on metal before. You need the reinforced wheels. I bought some on Ebay cheap and Lowes or HD has them.
 
A couple of things to try.

Quick-Glo. From Jay Leno's Garage. http://www.quick-glo.com/

W-D 40 Rust Release

Perhaps something like Zep Calcium, lime and rust remover.

Dupont aluminum cleaner

Now the way professional restorers do it is using Soda Blast but they have the knowledge and ability to know just the right pressure to use and know how. I doubt that's something an amateur can really do. However, if you have no luck, you might find and ask someone who restores items of various types. Unfortunately, the only one I know is from television, Rick's Restorations.
 
I feel your pain. One of the hardest, most frustrating jobs on the refit of my previous money pit (MKI Mainship 34, 1982) was just what you are facing.

Try this, get a small flat blade screwdriver with a large handle, medium length shaft. Bend the tip to a 90, perhaps cant it a bit for leverage for the angle you will be working. Make your tool narrow enough to fit in the channel. Make the end sharp but not needle end. Use narrow wire brush on your drill/grinder, medium stiff. Use PB blaster, WD40 or similar to soften up. Hook nose needle nose pliers. Dental mirror and dental tools can also help. Swear regularly as you fight this stuff. It will come out but it will fight you every step of the way. Took me 4 long days for 4 Windows. Lot if it came out in pieces, ripped strips and chunks. Not fun

Note. You must get ALL of it out of the channel or the new will not slide in.
 
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.080"s small indeed. A paint scraper or putty knife on edge might fit or you can also get dental picks at Harbor freight. I don't know how thick those vibrating saws are but that might be in the same range.
 
Greetings,
Mr. sd. I too have the abrasive cut off wheels for both my Dremel and die grinder but the angle is such that they will not fit at all. I have the Dremel wire brushes in a variety of profiles but again, won't fit. Thanks.

Mr. BB. I don't doubt the products you cite would work on surface corrosion but I'm talking masses (compared to a surface condition) of hardened material. CLR/Zep appears to be ineffectual. Alas, since retirement I have lost access to my micro soda blaster BUT it would have probably been the best device to conquer the problem...Thanks, as well.

Mr. M. Well, aren't WE the ray of sunshine this morning! I spent most of the day yesterday designing and fabricating/altering gouging tools. Along with my dental pick collection AND the prerequisite...ahem, nasty comments, I WAS able to make a bit of progress and I fully appreciate the necessity of clean, obstruction free tracks.

ALittleAngry.gif


Mr. MM. Some say my mind is a dark room...

giphy.gif


Thanks all thus far. Keep those cards and letters coming...
 
Greetings,
Mr. r. Nope, not SeaGlaze. The boat is a 1979 PennYan and the windows were purpose built for that specific application so replacement is NOT an option. Thanks for the lead. I'm thinking now that I may try Oxalic acid. It's used to clean and take concrete off of stuff. The saga continues...

giphy.gif
 
Greetings,
Mr. r. Nope, not SeaGlaze. The boat is a 1979 PennYan and the windows were purpose built for that specific application so replacement is NOT an option. Thanks for the lead. I'm thinking now that I may try Oxalic acid. It's used to clean and take concrete off of stuff. The saga continues...

giphy.gif

Salt away is a mix and contains Oxalic acid why don't you try some dish soap and a tooth brush or a little solvent it might be a mix of alumuim, dried grease with a salt chaser
 
I wonder, can you use a propane torch and heat these tracks?
The heat will force the metal to expand and crack the corrosion. Then maybe the acid can get in there to work better. Propane will not melt aluminum unless it is real thin.
 
Greetings,
Mr. sd. My first thought was heat BUT aside from the old fuzzies which are done and replacable (have new stuff on order), there is a piece of plastic that the glass slides on and is NOT available nor easy to remove. Rats! I gave the area of concern a good soaking with oxalic acid to see if that would soften things up. Possibly as has been suggested, the mere presence of water may also do the job.
 
Greetings,
<snip>...The grooves that accept the fuzzy are visible but quite inaccessible to mechanical scouring/scraping and are very small (in the order of .080").

I've tried sulfuric, hydrochloric acids and Starbright "Salt-away" with seemingly no reaction other than the HCl reacting with the Al. I can live with losing a bit of the Al IF it means easy removal of the deposits...<snip>

Phosphoric acid. Brand name Ospho. Various brands available at tractor trailer supplies... used to clean aluminum trailers, etc.

Very powerful stuff. Needs dilution, gloves, etc. Can be syringed into channels. Wash scrape.

Eats the corrosion more than aluminum.
 
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Since the two acids I tried do not seem to work, I might try a strong base (Easy Off oven cleaner or a straight lye solution). I do have access to glacial acetic and percloric (conc) acids so that may be next before the base...Thanks. Hydrogen peroxide perhaps?

Please be very careful of the base products you use. A base is much nastier to the eye than any acid. The two most dangerous chemicals to the eye in a typical home are oven cleaner and automatic dishwashing detergent. So if you use something like that, use eye protection and be sure to wash/rinse your gloves/hands very well afterwards.

The eye doc in me couldn't hold back.
 
RTF, I used to clean aluminum heat exchangers in large air handlers in hospitals and industrial plants. I designed my own coil cleaner using phosphoric acid as my base. It's the only acid which won't dissolve the aluminum faster than the oxide. You also need a surfactant. A simple formula would be a qt of phosphoric, a tablespoon of "Dawn" dishwashing detergent, dissolved in 1 1/2 gallon of water. Be sure to use safety glasses and old clothes. A plastic sprayer would make it a lot easier to handle. Just spray, let sit for about 15-20 minutes and brush/rinse it off. If you need to work on small vertical surfaces that are really bad, you can mix a batch a little stronger and thicken it with Cab-o Sil to a syrup to peanut butter consistency, use a toothbrush and just gently scrub the crud until it's gone, rinse, and finish off with the spray to get the surrounding surfaces. Good luck, Ben
 
I would use one of the new oscillating tools with the blade for removing grout in the thin window groves..

The blades quite thin and you should be able to "sand down" the aluminum puss .

Even house aluminum will create the aluminum oxide that will slow the dissolving process.
 
suggested that a while ago also a broken hack saw blade might work. IMO this needs a mechanical not chemical solution.
 
Are you really sure that the deposit is not just salt??
You said it tastes like salt!!
The most likely culprit is salt encrusted over time in the track.
The best way to remove it is simply irrigating with hot water and inserting a fine blade down the sides of the track.
 
I use cleaner Bonderite C-IC Aero aka Turco Alumaprep 33 followed by Bonderite M-CR 1001 Alodine 101 conversion coating. Once treated no oxidation. Aviation guys use it.
 
I feel your pain. One of the hardest, most frustrating jobs on the refit of my previous money pit (MKI Mainship 34, 1982) was just what you are facing.

Try this, get a small flat blade screwdriver with a large handle, medium length shaft. Bend the tip to a 90, perhaps cant it a bit for leverage for the angle you will be working. Make your tool narrow enough to fit in the channel. Make the end sharp but not needle end. Use narrow wire brush on your drill/grinder, medium stiff. Use PB blaster, WD40 or similar to soften up. Hook nose needle nose pliers. Dental mirror and dental tools can also help. Swear regularly as you fight this stuff. It will come out but it will fight you every step of the way. Took me 4 long days for 4 Windows. Lot if it came out in pieces, ripped strips and chunks. Not fun

Note. You must get ALL of it out of the channel or the new will not slide in.
:thumb::thumb::thumb: custom screwdriver
 
Greetings,
I got so frustrated chipping, I put it aside for a couple of days. I felt I was doing more damage to the aluminum than necessary, soooo....I think, after a bit of prep work, I'll try to set up something to run some fresh water through the channel over an extended period of time to attempt to either soften the deposit or wash it away. Thanks Mr. C. (post #21.)
 
RTF once mechanically cleaned as best u can, I use what the aviation guys use, it works to keep alum clean/ stable (no oxidation) for year or more. Cleaner Bonderite C-IC 33 Aero known as Turco Alumiprep 33. Then wash dry thoroughly. Apply conversion coating Bonderite M-CR 1001 Aero known as Alodine 1001. Capt Bill.
 
Greetings,
Mr. bg. Thanks for the suggestions although I think the Bonderite materials may be overkill for the use we will put the boat. The deposits most definitely resulted from use in salt water and subsequent poor maintenance. She will be used exclusively in fresh water and is now in the care of someone who will keep a close eye on developing problems...

giphy.gif



Report to follow...
 
I've just started ressurection on my 77 MS 34. Boat has been under shrinkwrap for the last two years in the shipyard by the sea. Windows are corroded open and fuzzy strip is flaking away. I've started using a flat blade screwdriver with sand paper on the end. Slow going but it's slowly removing the corrosion. I was thinking of trying a brass wire wheel laid into the channel once i can get the sliding windows fully open. Any ideas on where i might find the fuzzy strip?
 
Greetings,
Mr. A. I am sourcing MY fuzzy strips from a supplier who deals exclusively with Penn Yan parts so the likelihood of MY strips fitting your grooves are slim but if you have the dimensions and they are the same, I can pass on my source. I'm sure other members have better sources. Take heart. There will be fuzz at the end of the channel.
 
I've just started ressurection on my 77 MS 34. Boat has been under shrinkwrap for the last two years in the shipyard by the sea. Windows are corroded open and fuzzy strip is flaking away. I've started using a flat blade screwdriver with sand paper on the end. Slow going but it's slowly removing the corrosion. I was thinking of trying a brass wire wheel laid into the channel once i can get the sliding windows fully open. Any ideas on where i might find the fuzzy strip?

I have done an 82. May the boat gods smile on you. Join Mainship Owners Group, I think there is more than one. The Yahoo site is VERY good and you will find that many have plowed ground you are approching. Handy search option, you will find suppliers, vendors, techniques, traps to avoid and so on. A wealth of information once you filter out the questions from people that do not know what a screw driver is.

On your windows...2 2 by 4s. Hard wood, not pine. Trim one long enough to angle in the window opening. Mild angle. The second use against the base of the first and hammer #2 into #1 widening the gap so you can lift the glass out of the opening. I had to this a bunch of times. If they will not slide, saturate with wd40 or similiar to free em up then remove the glass.n then have fun!

Hint, with water intrusion on bridge, try a vacumm on low end and 1/2 lb of nitrogen on high end. Get the water out then you can seal and inject the soft spots.

I have a 4 blade fresh RH 21x21- 1 1/2 shaft prop. Will need a 1/8 bushing for your 1 3/8" shaft. I have no need for this prop.
 

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