Using the Sun to restore a yellow Macintosh ☀️

I've been looking at the safest ways to restore the color of the Mac without over bleaching the unit or leaving streak marks.

Because the inside of a Mac 128/512/Plus is coated with a conductive covering, I want to avoid submerging the case into hydrogen peroxide as it induces rusting/oxidation. I also want to avoid buying gallons of hydrogen peroxide.

The two methods I tried were using just the sun (nothing else!), and a hydrogen peroxide cream. Here is a before/after gif of a platinum bezel using the two methods.

Results Overview​

As seen in the gif, the center bezel is before and after. The bezel was place between a lightly yellowed bezel on the left and a heavily yellowed bezel on the right just for reference.
The sun was able to restore the color to a modestly yellowed state.
The creme did a much better job and was able to restore the color to a very slight yellowed state.
I was impressed with both results in general

Please note that the cream did NOT over brighten the bezel! From the area under the  logo, you can see that the original color was even brighter.

On the negative side for the cream. the bezel color was not evenly restored. On the left side of the inward CRT bend, there's extra yellowing, as highlighted in the image below. This is partially because it's difficult to get all the edges an equal amount of sun in such a short amount of time.

Sun Method​

Bezel was placed outside in the sun, in the middle of January, every day between 11am and 4pm (I get limit sun due to surrounding buildings). 2 of the days were sunny and 3 days were cloudy. Temperature was cold, about 6°C/43°F every day. I did check on it everyday and on cloudy days the bezel would get brighter as well. I would place the bezel at slightly different angles every day to ensure all edges got some sun. Only the top side came out a bit darker, but this can be easily fixed by placing it at an angle to focus on top side.

Below is an image of 4 Mac Plus platinum bezels. From left to right:
1. Original Color
2. Brightened via cream, original color can be seen where the  logo was removed.
3. Brightened via sun for 5 days
4. Heavily yellowed bezel (right side bezel from above gifs)

Lastly, I'd like to note that the 5 days of sun had no visible affect or discoloration on the  badge, however I'm sure that if I did leave it out for a couple weeks it would.

Cream Method​

I followed the method described in this youtube video.
Recipe (note this makes enough to do at least 5 macs!!):

• 500ml 3% hydrogen peroxide
• 1 tablespoon Xanthan Gum
• 2 tablespoons Glycerin
• 1/4 teaspoon Oxiclean power

I used a hand mixer to to mix everything, consistency came out very similar to video. I tried to re-apply cream every 15~20 minutes; I'd recommend every 15 as after 20 minutes it was starting to get a bit hard. It was in the sun for just about 2 hours.

Conclusion​

The sun did a surprisingly really good job! However it seems you'd probably need to leave it out in the sun for a month if you'd like to remove most of the yellowing.
The cream also did a great job, but it can be hard to get even results on a heavily yellowed bezel.
My final suggestion would be to leave the case out for 1~2 weeks in the sun, and then follow up with a 1 hour cream treatment to get that extra final mile.

 

[retr01]

Looking forward to the video. I like the idea of indoor retro briting.

As for using the sun, I have sunlight shining through my window every morning until around mid-afternoon. Will the window filter out the UV A or B? Is it effective to let my yellowed stuff sit on the floor in the sun from the window?

 

[catboyjack]

Coming along GREAT so far!
Tomorrow I'm doing the back casing and if all goes well that should be all the footage I need.

(I color matched my finished faceplate to my complete-in-box wall modem which hasn't yellowed it and the match is perfect!)

 

[catboyjack]

I only use that method now. It allows me to tackle things quickly because I can do it overnight and don't need to babysit. And as I said it's forgiving and I've not yet had anything come out splotchy. Let us know how it turns out. I've had so many people claim the plastic wrap is too dangerous, but I personally believe using the sun is the greater risk.

I gave it a shot today with my faceplate. I checked on it every 2 hours or so but the peroxide seemed to be drying out to a point I wasn't comfortable with. Maybe I didn't seal it good or apply enough, but for the rest of the project I'm going to stick to painting the cream on every hour.

I REALLY would like to find a way to where I can have it going overnight or while I'm at school/work, but this is a machine I dont want to risk damaging so I'll experiment more with plastic wrap on something less important to me.

 

[wottle]

I gave it a shot today with my faceplate. I checked on it every 2 hours or so but the peroxide seemed to be drying out to a point I wasn't comfortable with. Maybe I didn't seal it good or apply enough, but for the rest of the project I'm going to stick to painting the cream on every hour.

I REALLY would like to find a way to where I can have it going overnight or while I'm at school/work, but this is a machine I dont want to risk damaging so I'll experiment more with plastic wrap on something less important to me.

Yes, you have to make sure you get an airtight seal with your plastic wrap, which shouldn't be hard. I probably should have said this, but I assumed everyone did, but you have to wrap the back sides of the piece to make the component completely, 360 degree covered in plastic. It's not just the areas with peroxide. Otherwise I'm guessing the edges where air can come in from the edges will dry as the moisture escapes.

I've never had my peroxide be dry after 8-12 hours. I've got an AppleColor RGB Color Monitor that I got with a IIsi that is need of restoring. I'll try to take some pictures of my process and the results.

 

[catboyjack]

Yes, you have to make sure you get an airtight seal with your plastic wrap, which shouldn't be hard. I probably should have said this, but I assumed everyone did, but you have to wrap the back sides of the piece to make the component completely, 360 degree covered in plastic. It's not just the areas with peroxide. Otherwise I'm guessing the edges where air can come in from the edges will dry as the moisture escapes.

I've never had my peroxide be dry after 8-12 hours. I've got an AppleColor RGB Color Monitor that I got with a IIsi that is need of restoring. I'll try to take some pictures of my process and the results.

Alright, I'll defenitly give it a try then. My Mac Plus is in need of some retrobright to even out the coloring due to stickers.

I'll try it soon-ish and post my results as well.

(also with my Apple Keyboard II which is also in need of retrobright)

 

[Javmast3r]

Plastic wrap is well known to damage the plastics, but it is your prerogative. Don't blame retrobright later, as it's not the recommended or original method, but a lazy way to do it.
Cheers
Jav.

 

[catboyjack]

Plastic wrap is well known to damage the plastics, but it is your prerogative. Don't blame retrobright later, as it's not the recommended or original method, but a lazy way to do it.
Cheers
Jav.

Yeah, I never tried it again for that reason. Best just to put aside a weekend where I can check it every hour to reapply cream for a 12 hour session.

 

[wottle]

Plastic wrap is well known to damage the plastics, but it is your prerogative. Don't blame retrobright later, as it's not the recommended or original method, but a lazy way to do it.
Cheers
Jav.

Curious, what damage to the plastics? Also, there's a difference between lazy and forgiving. Using the sun is unforgiving. Using plastic wrap in the sun will result in problems with the finish. I'll agree with that. But I have seen zero evidence that simply using plastic wrap is the source of the problem. Maybe I should buy a lottery ticket because of fact that I've not destroyed any machines using this process, because statistically, if plastic wrap destroys plastics, I'm a unicorn.

I know we've been down this disagreement before, but I've personally seen less damage using LED lighting with creme and plastic than when I used the "approved" technique, mainly because of how sensitive the approved technique is to making sure you babysit it and get the timing just right. Other than the 20 or so machines I've used the technique on without a single instance of marbling, what could I do to not get a response of "Well , it may work for you, but I'd never recommend anyone do it because it will destroy your plastics"? I get the retrobright purists thinking the process is unique and cannot be improved, but I also think using wasteful processes because "this is how the first person did it" it an odd position for us as tech enthusiasts. Not trying to start an emacs vs. vi war here, just curious as to why we we seem to shut down people with prove success with claims that are usually backed by nothing more than speculation.

Gatekeeping a process that has so much community demand seems odd. I guess I'll just quietly keep using my technique successfully and others can continue wasting peroxide and having mixed results because of the variables involved with using the power of the sun. Best of luck anyone, if anyone is interested in an alternate technique, not to be confused with retrobrighting, feel free to reach out privately.

 

[wottle]

Plastic wrap is well known to damage the plastics, but it is your prerogative. Don't blame retrobright later, as it's not the recommended or original method, but a lazy way to do it.
Cheers
Jav.

Yeah, I never tried it again for that reason. Best just to put aside a weekend where I can check it every hour to reapply cream for a 12 hour session.

As with the warning from @Javmast3r, I hope you have better luck. Depending on heat, humidity, and the intensity of the sun, you could have terrible results if you only plan to check every hour. In the southern US, I had to reapply every 10 minutes or so, and even then, I saw streak marks in the finish (I believe due to uneven drying of the creme). Clearly my recommendations aren't going to get anyone's backings, but I will say just be careful doing this outside. The sun's strength is different in different parts of the world, so using the exact same technique as someone else may yield different results because of differences in the inputs. I prefer to keep my variables controlled. I think the best advice is to practice your chosen technique on items that are lower value until you have a repeatable, proven method. Then move on to machines that you hold in higher value.

 

[retr01]

I want to speak up and share my thoughts.

I prefer the scientific method. First, form a hypothesis. Second, set up the experiments with the control, placebo, and test sets. Third, observe and record results. Finally, see if the hypothesis is proved or disproved.

Many observations, discussions, and so forth, as I have seen here, YouTube videos, and other boards do not use the scientific method. Did anyone use the scientific method and share the data gathered? Engineers use the scientific method, too. If we want to engineer an excellent retrobriting method, then data needs to explain why the method is suitable.

I have been watching on the sidelines and will not try it because I do not see enough data backing a claim or another. Regardless, I am glad we are all trying to figure out the best way. So far, it seems there are different approaches and opinions.

When will someone use the scientific method and provide data to back the different methods such as plastic wrapping and chemicals, the sun, and UV lamps with the pros and cons to help make a more educated decision?

 

[Javmast3r]

Curious, what damage to the plastics? Also, there's a difference between lazy and forgiving. Using the sun is unforgiving. Using plastic wrap in the sun will result in problems with the finish. I'll agree with that. But I have seen zero evidence that simply using plastic wrap is the source of the problem. Maybe I should buy a lottery ticket because of fact that I've not destroyed any machines using this process, because statistically, if plastic wrap destroys plastics, I'm a unicorn.

I know we've been down this disagreement before, but I've personally seen less damage using LED lighting with creme and plastic than when I used the "approved" technique, mainly because of how sensitive the approved technique is to making sure you babysit it and get the timing just right. Other than the 20 or so machines I've used the technique on without a single instance of marbling, what could I do to not get a response of "Well , it may work for you, but I'd never recommend anyone do it because it will destroy your plastics"? I get the retrobright purists thinking the process is unique and cannot be improved, but I also think using wasteful processes because "this is how the first person did it" it an odd position for us as tech enthusiasts. Not trying to start an emacs vs. vi war here, just curious as to why we we seem to shut down people with prove success with claims that are usually backed by nothing more than speculation.

Gatekeeping a process that has so much community demand seems odd. I guess I'll just quietly keep using my technique successfully and others can continue wasting peroxide and having mixed results because of the variables involved with using the power of the sun. Best of luck anyone, if anyone is interested in an alternate technique, not to be confused with retrobrighting, feel free to reach out privately.

The damage is called streaking or marbling. It basically bleaches or burns some parts to an extent that it's not recoverable without damaging the plastic. I'm all for trying new techniques and experiments, but don't tell the world that your "plastic wrapping" is the recommended method. My caution words come from hearing tens of people saying retrobrite ruined their plastics, when they basically followed the wrong method.
Other than that I have experimented with other methods (oven, indoor, bleach, etc.) Found the sun and submersion to be the safer, followed by indoor, which in my case is a waste of time and energy having great sunlight 365 days.
Here is a link of somebody that followed the scientific method:

Retrobright 2.0 - No more UV light! - deskthority

 

[wottle]

The damage is called streaking or marbling. It basically bleaches or burns some parts to an extent that it's not recoverable without damaging the plastic. I'm all for trying new techniques and experiments, but don't tell the world that your "plastic wrapping" is the recommended method. My caution words come from hearing tens of people saying retrobrite ruined their plastics, when they basically followed the wrong method.
Other than that I have experimented with other methods (oven, indoor, bleach, etc.) Found the sun and submersion to be the safer, followed by indoor, which in my case is a waste of time and energy having great sunlight 365 days.
Here is a link of somebody that followed the scientific method:

Retrobright 2.0 - No more UV light! - deskthority

O

I've never said it's the recommended method. You are the only one making claims to what can be the approved / recommended / original / authorized method. Odd to be accused of that as all I've said is that it has worked for me for many projects and has never caused marbling or streaking, and I specifically talk about the dangers of plastic wrap when doing it in sunlight. The truth is, using plastic wrap with low intensity UV LEDs is, in my opinion, safer than doing submersion or reapplication of creme in the sun due to the incredible variability of the sun's intensity, heat, etc. This is backed by personal experience and issues I've had with other techniques. While submersion may be safer, it is incredibly wasteful and means you'll have to deal with pieces that want to float, so you must weight them down without blocking the sunlight.

The fact of the matter is all of these techniques carry risk. The difference is that I'm not blindly dismissing a particular technique because I don't like it or I've heard stories where people used a different technique with a single thing in common and write it off completely. The damage you describe certainly has been caused by using plastic wrap in a way completely different to what I have discussed. It's the equivalent to me telling people never to do submersion because someone did submersion in sulfuric acid.

Also, the scientific method you link doesn't use sunlight (your method) or peroxide creme with UV LEDs (no heat, my method). It's also incredibly unscientific (not sure how long they were left in the sous vide, not specific about the concentration of the peroxide in the bag). So it's hard to draw any conclusions other than you believe your method is better and provide "scientific proof" that shows a vague, completely different approach can work. Which is 100% fine. The problem I have is when you make blanket statements dismissing other approached, then send links to a different approach from yours as proof your opinion is best.

If you can point me to someone who destroyed their plastic with streaking or marbling using the method I discussed (peroxide creme, applied evenly, covered with bubble free plastic wrap, put in a UV light box overnight), I'd love to see it. Otherwise, you're just purposefully spreading misinformation for some unknown reason (are you a peroxide salesman as your side job? . Your prerogative, but certainly you and I both know you aren't improving the community in doing so. So, I'd love to see any, because I certainly looked for evidence of that before I went through the effort and expense of building my UV light box. If you provide that, we can continue this conversation. Until then, trolling people in the forums seems like the kind of behavior TinkerDifferent was created to avoid.

Best of luck. I believe you think you are protecting people from making a mistake, but in doing so you're just calling me a liar and it's pretty concerning. What reason would I have to lie about my successes? What reason do you have to make people believe I'm lying about the technique I use? I'm really baffled by both your insistence on calling me out, while simultaneously never being willing to address my actual technique, only calling out other, improperly applied techniques as reasons to avoid the one I'm using.

 

[Javmast3r]

I've never said it's the recommended method. You are the only one making claims to what can be the approved / recommended / original / authorized method. Odd to be accused of that as all I've said is that it has worked for me for many projects and has never caused marbling or streaking, and I specifically talk about the dangers of plastic wrap when doing it in sunlight. The truth is, using plastic wrap with low intensity UV LEDs is, in my opinion, safer than doing submersion or reapplication of creme in the sun due to the incredible variability of the sun's intensity, heat, etc. This is backed by personal experience and issues I've had with other techniques. While submersion may be safer, it is incredibly wasteful and means you'll have to deal with pieces that want to float, so you must weight them down without blocking the sunlight.

The fact of the matter is all of these techniques carry risk. The difference is that I'm not blindly dismissing a particular technique because I don't like it or I've heard stories where people used a different technique with a single thing in common and write it off completely. The damage you describe certainly has been caused by using plastic wrap in a way completely different to what I have discussed. It's the equivalent to me telling people never to do submersion because someone did submersion in sulfuric acid.

Also, the scientific method you link doesn't use sunlight (your method) or peroxide creme with UV LEDs (no heat, my method). It's also incredibly unscientific (not sure how long they were left in the sous vide, not specific about the concentration of the peroxide in the bag). So it's hard to draw any conclusions other than you believe your method is better and provide "scientific proof" that shows a vague, completely different approach can work. Which is 100% fine. The problem I have is when you make blanket statements dismissing other approached, then send links to a different approach from yours as proof your opinion is best.

If you can point me to someone who destroyed their plastic with streaking or marbling using the method I discussed (peroxide creme, applied evenly, covered with bubble free plastic wrap, put in a UV light box overnight), I'd love to see it. Otherwise, you're just purposefully spreading misinformation for some unknown reason (are you a peroxide salesman as your side job? . Your prerogative, but certainly you and I both know you aren't improving the community in doing so. So, I'd love to see any, because I certainly looked for evidence of that before I went through the effort and expense of building my UV light box. If you provide that, we can continue this conversation. Until then, trolling people in the forums seems like the kind of behavior TinkerDifferent was created to avoid.

Best of luck. I believe you think you are protecting people from making a mistake, but in doing so you're just calling me a liar and it's pretty concerning. What reason would I have to lie about my successes? What reason do you have to make people believe I'm lying about the technique I use? I'm really baffled by both your insistence on calling me out, while simultaneously never being willing to address my actual technique, only calling out other, improperly applied techniques as reasons to avoid the one I'm using.

Hey, foremost, we are all friends here, no bad blood. If my words sounded like accusing you of anything, I apologize. Don't come here to fight, just to share experiences and learn from each other.
I can point you to a person that has destroyed plastics: me. I didn't learn what I know by doing it all right. Can't show, as I either scraped them or used them for projects, like the black //c or the painted Atari Drive. There are lots of photos online of Amigas and commodores marbled to check.
My comments are advisory, not to force people to do it a certain way. Hence, my point that is your item, and you are free to do what you want.
Cheers and happy retro computing!

 

[wottle]

Hey, foremost, we are all friends here, no bad blood. If my words sounded like accusing you of anything, I apologize. Don't come here to fight, just to share experiences and learn from each other.
I can point you to a person that has destroyed plastics: me. I didn't learn what I know by doing it all right. Can't show, as I either scraped them or used them for projects, like the black //c or the painted Atari Drive. There are lots of photos online of Amigas and commodores marbled to check.
My comments are advisory, not to force people to do it a certain way. Hence, my point that is your item, and you are free to do what you want.
Cheers and happy retro computing!

I appreciate the response. However, you never seem to address my question. None of those results, including yours. have been linked to using plastic wrap in lower intensity UV LEDs without the extreme heat of the sun. Even the study you provided presents the hypothesis that bleaching is the result of heat. Most likely cause by using plastic wrap *in the sun*, which is not what I have presented. I too have destroyed plastics (hence my black Performa 5400). Sadly it was done using a process I've seen claimed to be safe - reapplying creme in the sun every 15 minutes. In the hot SC sun, that caused horrendous streaking.

Please, show me some link to those destroyed plastics and the process I've describes. If you really are wanting to provide good advice, you can at least address the issue at hand. Or, continue to dance around it. People shouldn't have to read 20 posts to find the truth. You'd obfuscating the truth with these posts and making it unnecessarily hard on users to get to an educated decision on what approaches will work best for them.

 

[Javmast3r]

I'm afraid every time people sent me results, via email, messenger, and Facebook groups, I didn't save the images to satisfy your curiosity. You are free to search Facebook's apple II groups, Forums and emails from 8 to 10 years ago, when I had those discussions. My good advice comes from eight years of retrobrite, and other than obfuscate, i like to create awareness and save people from those mistakes. I will expect your videos and photos showing me your truth. Cheers!
Jav

 

[wottle]

I'm afraid every time people sent me results, via email, messenger, and Facebook groups, I didn't save the images to satisfy your curiosity. You are free to search Facebook's apple II groups, Forums and emails from 8 to 10 years ago, when I had those discussions. My good advice comes from eight years of retrobrite, and other than obfuscate, i like to create awareness and save people from those mistakes. I will expect your videos and photos showing me your truth. Cheers!
Jav

So your statement is that others (or you) have run into marbling and streaking using UV LED strips and plastic wrap? (i.e. not from cooking the peroxide in the sun with plastic wrap).

Appreciate the passive-aggressive laughing at my post and then not answering the question. Sorry if you could't pull yourself up off the floor to address a question I've asked in 4 consecutive posts.

Let me know exactly what you want me to show in the video and I'll show it.

 

[Javmast3r]

Nope, never by using UV LED strips and plastic wrap.

 

[catboyjack]

I don't firmly believe there's an objectively "Right" way to retorbright. There's a lot of different formulas out there with different amounts of success documented.

It's up to us to document them and formulate a more scientific process rather than arguing which method is the best. As stated before I am working on a documentary-esk video on MY process, but it's intention isnt to sell people on "my method being the best" it's to inform people of the alternatives to widely known plastic wrap w/ cream in the sun or submerging.

That being said, the process I follow and have documented here previously isn't a 100% be all save all method, it has downsides like all methods and may not work best for everyone, it's just what I've found to work best for ME in both my living situation and financial situation. (I've just been lucky enough to get near perfect results with the 5 or 6 machines I've treated over the last year).

I really would like to see everyone combine notes from different processes and come down to a scientific consense on what could be the best method or at least develop a process that a majority of people could go through without critical failure.

Cheers,

Jack.

 

[retr01]

For sure! It would be nice to have various folks post what works, pictures, and the pros and cons of using that method. Then we have a collection of unbiased and well-documented approaches to retrobriting that fit someone based on circumstances and materials that could obtain. For example, the chemical bath approach may not work for some people who cannot get the materials, but another system will work. The processes need to be done right for each retrobrite approach, hence the need for clear and detailed instructions for different successful approaches.

Those should be done in a FixIt or Instructables format with pictures and maybe add a video for visualizing the processes.

I know this thread mainly focuses on retrobriting using the sun. Some people do not have the option to use the sun.

 

[Javmast3r]

great idea! I have several videos, interviews and lectures on retrobrite, in my channel and others like Chris Torrence, KansasFest and Retro Repair Roundup. I will look forward to other’s videos demonstrating their techniques and successes, I do that every year for the last 5 at KansasFest and lately VCF East.