How yellow do they get?

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How yellow do they get?
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This is the worst I've seen. RetroBrite...here I come!

Another call for first aid!

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Re: How yellow do they get?

In the words of the immortal Strongbad - "Holy crap."

http://www.hark.com/clips/yntwwmkcwm-holy-crap

That thing is the poster child for Retr0brite.

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Re: How yellow do they get?

Not quite as yellow as that example, but here's a good example of what the Retr0bright process can accomplish:

Tried to get similar lighting in both shots, and there is no colour correction applied.
IMAGE(http://lh5.googleusercontent.com/-jsx0hsG56uw/TcrN3nRlgtI/AAAAAAAAAeA/TD8UqRyFQ5Q/w1024-h414-no/before-after.jpg)

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Re: How yellow do they get?

That is an excellent result. Did you also do the keycaps? Did you encounter any fading of the lettering?

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Re: How yellow do they get?

I understand that you should do a little Armour-All as a UV protectant. This prevents re-yellowing.

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Re: How yellow do they get?

That is an excellent result. Did you also do the keycaps? Did you encounter any fading of the lettering?

It was a few years ago, but I'm pretty sure I did the whole keyboard. The space bar was the worst culprit, as you can see in the photo. There was a little fading, but very minimal.

I understand that you should do a little Armour-All as a UV protectant. This prevents re-yellowing.

I'd recommend that as a necessary part of the process. I didn't, and with an 840av case I did at the same time as the IIc, the case has slightly re-yellowed. It's not back to pre-Retrobright yellow, but it's darkened enough to be noticeable.

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Re: How yellow do they get?

Forgot to mention that first sucker I posted I found on eBay. Someone has their work cutout for them.

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Re: How yellow do they get?

In the words of the immortal Strongbad - "Holy crap."

http://www.hark.com/clips/yntwwmkcwm-holy-crap

Seriously, where do you find this stuff? I would never, ever, play Jeopardy against you.

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Re: How yellow do they get?

I've seen heard about many variants for this Retrobright -- http://en.wikipedia.org/wiki/Retrobright -- but I'm wondering if there is some sort of household cleaner or all-in-one product that is almost as effective, i.e. it takes longer or several applications to get the job done.

I'm experimenting around with professional chlorox bleach and find that it about 20% as effective as the genuine formula. Maybe it's working by a different method?

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Re: How yellow do they get?

I have discovered that retr0brite is not as easy to do as you think. It took me 2 years to get it right. And BTW: It takes 24 hours to work.

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Re: How yellow do they get?

Bright sunlight and a couple hours were all I needed for the IIc above. What concentration of peroxide were you working with?

Agreed it's tricky to work with. I was left with lots of white 'blooming' after a later Retr0bright attempt on an Atari ST case. I ended up painting the case.

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Re: How yellow do they get?

because the formulation are generally created using locally available ingredients, the result varies from region to region. does it make sense for people to share their region and specific brands of ingredients used?

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Re: How yellow do they get?

It would. I mostly hear success stories coming from countries other than mine, where they seem to be able to get access to products that are either nonexistent in anything resembling a store I would frequent (xantham gum? wazzat?) Or take a cosmetologist's license to acquire (peroxide at 34%? What, are you making a bomb?).

Noting, of course, that the real home of Retr0bright is here:
http://retr0bright.wikispaces.com/

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Re: How yellow do they get?

I was thinking of something like a Hydro powered Retr0brite pen.

Something were you mix up all the chemicals and heat them to some arbitrary high temperature like 80`C and spray them out of an airbrush-like tool.

You'd get even coverage and I can't imagine it not helping with blooming and mottling. Or maybe it will work in real-time if you get enough UV going and crank it 95`C ?

And it's not like the chemicals will be wasted, they'll flow into a collection tub and just recirculate through.

I can see it now, a whole conveyer system going, with sprayers and lights and and fans and stuff!

I could set this up in the shed and charge people like $10.00 to restore a housing.

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Re: How yellow do they get?

That's now half as bad as they get. I've seen them get to actual dark yellow/brown.

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Re: How yellow do they get?

Got a housing that is cardboard-box-brown.

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Re: How yellow do they get?

I was thinking of something like a Hydro powered Retr0brite pen.

Something were you mix up all the chemicals and heat them to some arbitrary high temperature like 80`C and spray them out of an airbrush-like tool.

You'd get even coverage and I can't imagine it not helping with blooming and mottling. Or maybe it will work in real-time if you get enough UV going and crank it 95`C ?

And it's not like the chemicals will be wasted, they'll flow into a collection tub and just recirculate through.

I can see it now, a whole conveyer system going, with sprayers and lights and and fans and stuff!

I could set this up in the shed and charge people like $10.00 to restore a housing.

Therein lies the exact problem. Retr0brite, when mixed with too much Xanthan Gum, will not liquefy within the 24 hour period. The liquefying process time differential is the key to using it successfully. It must liquefy in approximately 24 hours, foam up in 1 to 2 hours and never dry up. I use 10 - 12% hydrogen Peroxide. It also needs maintenance - you must continually attempt to brush it evenly; every hour and within the first 12 hours in order to get the even coverage desired. Too much gel over the plastic and the light cannot penetrate through. The gel formula posted on the website is incorrect. That is why I had such a hard time with it.

Now when I do the process I get even coverage almost all the time depending on the shape of the plastic and how I maintain it. It is an art to work with this stuff.

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Re: How yellow do they get?

I would like to share my experience and opinion on Retrobrite:
I have used it for all my //c projects, all with excellent results. The peroxide I like is the one from Beauty Supplies, I get the 40%.
After some reading, I understood that the xantam gum and other variants are used to thicken the mix, it really doesn't affect the results. I personally use Arrowroot (the only thing I found) and original Oxy Clean. I heat for 20 seconds in the microwave the peroxide, then add the arrowroot, mix, heat it again 20 more seconds and add OxyClean. This helps the mix to dissolve perfectly. My technique is to apply it with a brush evenly, then every hour or two take it out of the sun, rinse it and wash it with water and reapply retrobrite. Sometimes takes a full day, others just a few hours, depending on the level of yellowing and the sunny day. Remember to use gloves, it burns your skin and clothes very easy.
I hope this helps.
Javster

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Re: How yellow do they get?

In my experience, the amount of Xanthan Gum definitely affects the results. Too much of it and it will dry up, those portions will make those parts whiter than the rest. Too little Xanthan Gum and it will liquefy too early and the mixture will have to be re-done. The magic amount of Xanthan Gum is the key to getting the right results. It's vital!

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Re: How yellow do they get?

where I live a lot of the ingredients to make up retrobrite are far to difficult to come by and/or expensive. From my own experience with very yellowed //c and iigs, I simply used what I can readily get from local grocery stores. The only ingredient I use and use with 100% success in de-yellowing is oxy-clean (powder), warm water and a sizeable bin that I can submerge all the parts of the computer, and let them sit under the bright sun. best results I have gotten to getting all the yellow out is 5-6 hrs in the sun. since the de-yellowing of both machines (2 yrs with the //c, and 5 months with the IIgs) I haven't seen any of the yellow come back to the casings yet, and I haven't put any UV protectant on them. If you want somethings super cheap, and no science or recipe.. my vote goes to warm water and powdered oxyclean.

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Re: How yellow do they get?

where I live a lot of the ingredients to make up retrobrite are far to difficult to come by and/or expensive. From my own experience with very yellowed //c and iigs, I simply used what I can readily get from local grocery stores. The only ingredient I use and use with 100% success in de-yellowing is oxy-clean (powder), warm water and a sizeable bin that I can submerge all the parts of the computer, and let them sit under the bright sun. best results I have gotten to getting all the yellow out is 5-6 hrs in the sun. since the de-yellowing of both machines (2 yrs with the //c, and 5 months with the IIgs) I haven't seen any of the yellow come back to the casings yet, and I haven't put any UV protectant on them. If you want somethings super cheap, and no science or recipe.. my vote goes to warm water and powdered oxyclean.

You don't use any hydrogen peroxide at all...?

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Re: How yellow do they get?

You don't use any hydrogen peroxide at all...?

Oxy-clean is mainly sodium percarbonate, which when dissolved breaks down into sodium carbonate and hydrogen peroxide. So Oxy-clean on its own offers some Retr0bright properties.

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Re: How yellow do they get?

yes thats correct on oxyclean. its also friendly to the environment once you are all done with the solution.

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Re: How yellow do they get?

So that's why straight oxy-clean worked on my Mac Classic in the dishwasher? Neat!!

I'll keep this in mind, since H202 is a bit pricey.

c

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