100% Lye yellowing?

[Dpate]

7 hours ago, 1930fordpickup said:

If you try something different please post results good and bad. Good information on what to do and what not to do is always welcome on here.  

Will do.  

[Mr. Metallic]

On 10/14/2021 at 2:57 PM, Dpate said:

Well when i use it i keep it in a 2 gallon plastic container with locking lid.  I put whole entire chrome tree's into it, works amazing when it's fresh.  I can tell it's getting used up because it takes a whole lot longer to strip anything - like sometimes it gets so weak it wont even touch the chrome.  So straining it i don't think would do any good if the stripping properties are already used up.  Could i put the lye into the super clean considering it already has it in there or putting 100% lye into a chemical like that is a bad idea?

Like others have said, i usually use mine about 1 1/2 years before i feel the need to change it out. But, you're not wrong, over time (or volume) it does lose it's strength. But the reason it does is if you don't remove the contaminates (paint/chrome/undercoat/etc) the formula continues to attack that stuff. If you strain it after each session it should last much longer. I have used a painters filter in the past (the kind automotive painters strain paint through before painting) The mesh is very fine and should catch most of your solids.

[Mr. Metallic]

duplicate post

Edited October 19, 2021 by Mr. Metallic

[StevenGuthmiller]

38 minutes ago, Mr. Metallic said:

Like others have said, i usually use mine about 1 1/2 years before i feel the need to change it out. But, you're not wrong, over time (or volume) it does lose it's strength. But the reason it does is if you don't remove the contaminates (paint/chrome/undercoat/etc) the formula continues to attack that stuff. If you strain it after each session it should last much longer. I have used a painters filter in the past (the kind automotive painters strain paint through before painting) The mesh is very fine and should catch most of your solids.

I don’t know.

The only time that I strain mine is right before I dispose of it.

But I suppose that there could very well be some validity to the theory that cleaning it out might extend its usefulness.

 

 

 

 

Steve

[Dpate]

2 hours ago, Mr. Metallic said:

Like others have said, i usually use mine about 1 1/2 years before i feel the need to change it out. But, you're not wrong, over time (or volume) it does lose it's strength. But the reason it does is if you don't remove the contaminates (paint/chrome/undercoat/etc) the formula continues to attack that stuff. If you strain it after each session it should last much longer. I have used a painters filter in the past (the kind automotive painters strain paint through before painting) The mesh is very fine and should catch most of your solids.

That makes sense now that you explain it that way.  I got a heated ultrasonic cleaner coming in tomorrow, and it'll allow me to set it to whatever temp i want and should do alot better than just having the parts sitting in the liquid.  

[Rodent]

I have been building for over 50 years, and I made a rookie mistake this week. Blew some primer on some Revell parts without cleaning them, and the primer reacted like I had dipped the parts in olive oil. Some of the parts were Rustoleum primer, some were Tamiya. They were all dumped in the Purple Pond before they were dry, but the Tamiya parts are still swimming long after the Rustoleum floated away. It is getting cooler here (40s at night), so I brought the pond into the house from the garage. Didn't seem to help much. Going to see what I can do with a toothbrush in a bit. I seem to have difficulty with Tamiya no matter what I try to remove it with.

[peteski]

4 hours ago, Dpate said:

That makes sense now that you explain it that way.  I got a heated ultrasonic cleaner coming in tomorrow, and it'll allow me to set it to whatever temp i want and should do alot better than just having the parts sitting in the liquid.  

Be careful. Lye is caustic and attacks metal!  If the ultrasonic cleaner has a metal tub, it might not be compatible with Lye.  Also the liquid might bubble and splash out of the tub.

[Plowboy]

2 hours ago, Rodent said:

I have been building for over 50 years, and I made a rookie mistake this week. Blew some primer on some Revell parts without cleaning them, and the primer reacted like I had dipped the parts in olive oil. Some of the parts were Rustoleum primer, some were Tamiya. They were all dumped in the Purple Pond before they were dry, but the Tamiya parts are still swimming long after the Rustoleum floated away. It is getting cooler here (40s at night), so I brought the pond into the house from the garage. Didn't seem to help much. Going to see what I can do with a toothbrush in a bit. I seem to have difficulty with Tamiya no matter what I try to remove it with.

Degreasers don't seem to work well on Tamiya. I had to use 91% alcohol to strip one. 

[Dpate]

20 hours ago, Rodent said:

I have been building for over 50 years, and I made a rookie mistake this week. Blew some primer on some Revell parts without cleaning them, and the primer reacted like I had dipped the parts in olive oil. Some of the parts were Rustoleum primer, some were Tamiya. They were all dumped in the Purple Pond before they were dry, but the Tamiya parts are still swimming long after the Rustoleum floated away. It is getting cooler here (40s at night), so I brought the pond into the house from the garage. Didn't seem to help much. Going to see what I can do with a toothbrush in a bit. I seem to have difficulty with Tamiya no matter what I try to remove it with.

Haven't tried stripping tamiya primer as that's not my main primer even though i have a fresh can.  I mainly use alclads primer, mr surfacer, and titan hobby by ak which is AMAZING primer probably even better than tamiya.  There black is so nice I'll use it for anything that is matt black. 

17 hours ago, peteski said:

Be careful. Lye is caustic and attacks metal!  If the ultrasonic cleaner has a metal tub, it might not be compatible with Lye.  Also the liquid might bubble and splash out of the tub.

The removable tub is stainless steel so hopefully that wont have an issue, and it'll only be at 70F with a lid so shouldn't bubble that bad or if at all.  People that use it for soap use at around 100+.

EDIT: Yeah just looked it up and found this: " Lye reacts with some metals: aluminum, zinc, and tin. Safe containers include heatproof stoneware, glass, enamel, stainless steel and plastic." 

Edited October 20, 2021 by Dpate

[peteski]

Ok, hopefully stainless steel will be safe.  As far splashing goes, it is not bubbles from heat - the ultrasonic cavitation effect can cause the fluid to bubble (at any temperature).

[Dpate]

47 minutes ago, peteski said:

Ok, hopefully stainless steel will be safe.  As far splashing goes, it is not bubbles from heat - the ultrasonic cavitation effect can cause the fluid to bubble (at any temperature).

Gotcha! I will def keep a close eye on it.

[Dpate]

So everything is good with the ultrasonic cleaner.  At 40C i know pretty high, but it cleans great and doesn't affect the lye at all or the parts. 104F is safe because i do 110F in my dry booth. Still a spot or two on the parts of the clear left, and that's after taking it out the lye bath it was already in for days, and than putting the parts into the ultrasonic cleaner for multiple 20 min cycles at 40C.  Don't know what they used - because it's the most toughest stuff to get off compared to any kit I've ever de-chromed.  Also 100% lye does NOT yellow parts or have any ill affect on the parts.  

Edited October 22, 2021 by Dpate

[peteski]

I'm glad you were successful.

While 99% manufacturers use the standard vacuum metalizing (thin layer of aluminum) to simulate chrome, there are couple companies that actually electroplate their "chrome" parts. That result in relatively thick layer of metal on the parts which is pretty much impossible to remove chemically. Even scraping it with a knife is very difficult.

One of those companies is Trumpeter, and I don't remember the other company. I think they make NASCAR or funny car kits.  Salvinos?

Edited October 23, 2021 by peteski

[Dpate]

14 hours ago, peteski said:

I'm glad you were successful.

While 99% manufacturers use the standard vacuum metalizing (thin layer of aluminum) to simulate chrome, there are couple companies that actually electroplate their "chrome" parts. That result in relatively thick layer of metal on the parts which is pretty much impossible to remove chemically. Even scraping it with a knife is very difficult.

One of those companies is Trumpeter, and I don't remember the other company. I think they make NASCAR or funny car kits.  Salvinos?

Yeah this is a AMT kit.  Super clean or 100% lye would not remove the underlayer from certain spots.  Don't know what chemical could be used to remove stubborn spots like that besides using to #11 blade to get it off, and than you got to sand that back right.  Like the spots that were left over was stained with super clean(Now shiny), and even the 100% lye wouldn't even get that off.

Edited October 23, 2021 by Dpate

[peteski]

Sometimes there is no substitution for some manual scraping.

[Dpate]

50 minutes ago, peteski said:

Sometimes there is no substitution for some manual scraping.

True that.  I guess it's just part of modeling.

[Bainford]

On 10/23/2021 at 7:05 PM, Dpate said:

Super clean or 100% lye would not remove the underlayer from certain spots.  Don't know what chemical could be used to remove stubborn spots like that besides using to #11 blade to get it off, and than you got to sand that back right. 

91% or 99% isopropyl alcohol can be effective at removing the lacquer undercoat. When all else fails, I soak it in brake fluid.

[Dpate]

7 hours ago, Bainford said:

91% or 99% isopropyl alcohol can be effective at removing the lacquer undercoat. When all else fails, I soak it in brake fluid.

May give the isopropyl a try next go around.  Thanks