Albert Posted February 8, 2009 Share Posted February 8, 2009 @ Moderators Would it be possible for this thread to be made a "Sticky"? Thanks Sure, and Done.. It would be helpful if this information was compiled together on a single page somewhere, as this thread is getting pretty long and has information scattered about its pages.. ..Al Quote Link to comment Share on other sites More sharing options...
+poobah Posted February 9, 2009 Share Posted February 9, 2009 @ Moderators Would it be possible for this thread to be made a "Sticky"? Thanks Sure, and Done.. It would be helpful if this information was compiled together on a single page somewhere, as this thread is getting pretty long and has information scattered about its pages.. ..Al On other forums, you'll see a sticky thread with the most up-to-date info in the first post, while commentary continues in the thread. Seems like that would be appropriate here (recipe and instructions in first post) Quote Link to comment Share on other sites More sharing options...
akator Posted February 9, 2009 Share Posted February 9, 2009 I was wondering if cleaners containing oxalic acid would work. For example, FSR (Fiberglass Stain Remover) is a gel available from boat stores (like West Marine) that manages to get yellowing and oxidation out of fiberglass. I'm not too willing to try it unless the chemistry would hold up... Quote Link to comment Share on other sites More sharing options...
harpo Posted February 9, 2009 Share Posted February 9, 2009 I've been away and I'm glad to this this is working for folks. No, oxalic acid will not work in the same way as this method. It may work, but my guess is there would be more degradation and surface oxidation of the plastic. The epoxy based polymers used in fiberglass composite boat hulls or shower stalls are much more crosslinked and inert than the ABS used in electronic component cases. The beauty of this procedure is that it is a "surgical strike" targeted directly at the bromine compounds causing the yellowing not a "carpet bombing" campaign that affects a whole region. Quote Link to comment Share on other sites More sharing options...
Merlin Posted February 9, 2009 Share Posted February 9, 2009 "Surgical strike".... I like that, you have a way with words, Harpo....... Quote Link to comment Share on other sites More sharing options...
akator Posted February 9, 2009 Share Posted February 9, 2009 No, oxalic acid will not work in the same way as this method. It may work, but my guess is there would be more degradation and surface oxidation of the plastic. The epoxy based polymers used in fiberglass composite boat hulls or shower stalls are much more crosslinked and inert than the ABS used in electronic component cases. Thanks Quote Link to comment Share on other sites More sharing options...
Merlin Posted February 9, 2009 Share Posted February 9, 2009 Sure, and Done.. It would be helpful if this information was compiled together on a single page somewhere, as this thread is getting pretty long and has information scattered about its pages.. ..Al There's a Wiki in progress; link here:- http://retr0bright.wikispaces.com/ I'll be working on the science bits this weekend.......... Quote Link to comment Share on other sites More sharing options...
Bryan Posted February 9, 2009 Share Posted February 9, 2009 I thought of something when I saw that Bob's Red Mill Xanthan Gum. We've got a local heath food/nutrition store that carries a large selection of Bob's Red Mill products. So, that might be a good place to start. Quote Link to comment Share on other sites More sharing options...
Merlin Posted February 9, 2009 Share Posted February 9, 2009 (edited) @ Bryan That's why I chose Xanthan Gum; there's no point in using chemicals that the average Joe can't get hold of.... @ akator Epoxy resins are thermoset chemistry, totally different to the thermoplastic ABS were are working with on the cases. Edited February 9, 2009 by Merlin Quote Link to comment Share on other sites More sharing options...
+Guitarman Posted February 10, 2009 Share Posted February 10, 2009 (edited) Ok. Here's my initial results. I made sure to white balance the camera before taking the pictures so there is no false yellowing in the pictures. First I did an 810 case. Before Shots After Shots As you can see, the drive case is back to a tan color as opposed to yellowed. I did the top half twice so, as you can see, the top half is a bit brighter. Then I did a 1200XL case. Unfortunately, I didn't get 'before' pictures of the 1200XL but trust me, it was a nice shade of pee!! 1200XL After Shots Again, as you can see, the case is a very nice original creme color. I have a 1200XL in the box that I compared it too and they look identical in color now. I am going to do a badly yellowed 800XL and 1050 case next. Will post results. Edited February 10, 2009 by Guitarman Quote Link to comment Share on other sites More sharing options...
mimo Posted February 10, 2009 Author Share Posted February 10, 2009 Excellent, thanks for posting your pictures. Quote Link to comment Share on other sites More sharing options...
Merlin Posted February 10, 2009 Share Posted February 10, 2009 Nice, thanks Guitarman. I am thinking of adding a gallery of some of these pictures once I've written up the scientific bit. If anyone has any parts being treated that they want adding to the Wiki, please post the before and after pictures. Thanks Quote Link to comment Share on other sites More sharing options...
sl0re Posted February 11, 2009 Share Posted February 11, 2009 (edited) Did it myself this last weekend as a test. Worked as advertised. I tested the claims by leaving the brown plastic and silver stripe and case badge on an 800xl. No damage to anything, plastic still has a shine / does not seem burned or bleached, and it removed the yellowing. Will use it again. PS Used off the pharmacy shelf 6% peroxide (cheap at target) and a everyday white grow white light (nothing special, its a $10 one for my indoor blub flower plants) overnight and three hours of dim / cloudy sun light. Did not add thickeners, just brush reapplied whenever I thought of it. Did not take before and after pictures but the change was obvious to see. It was a really bad looking yellowed 800xl when I started and now it looks like others I have that look fine. Also, top case was much more yellowed than bottom case and now it is reversed... the light yellowing of the bottom case sticks out compared to the top. Also, if you try it, remember these things are cream colored, not white. Edited February 11, 2009 by sl0re Quote Link to comment Share on other sites More sharing options...
Tempest Posted February 11, 2009 Share Posted February 11, 2009 Woot! I found Arrow Root yesterday so I'll try this over the weekend. Anything special i should know using Arrow Root over Xanthan Gum? Tempest Quote Link to comment Share on other sites More sharing options...
Merlin Posted February 11, 2009 Share Posted February 11, 2009 (edited) @ Tempest Yeah. Tezza at VCF said that if you use Arrow Root, you may need to heat the mixture slightly; don't worry, this is safe. Just leave it to cool before you use it. Tezza microwaved his for 30 seconds but didn't state the wattage of his oven. I would give it 20 seconds, stir it and and see how you get on. Tezza also said that you may need a couple of spoons of it to get a gel. @ Sl0re Where's the pictures? I wants me hardware pr0n..... Edited February 11, 2009 by Merlin Quote Link to comment Share on other sites More sharing options...
Tempest Posted February 11, 2009 Share Posted February 11, 2009 Why do I have visions of this catching fire in my microwave... How thick should it be before using? Toothpatse thick or more runny than that? Do I use the same amount of Arrow Root as I do of the Gum? Tempest Quote Link to comment Share on other sites More sharing options...
Merlin Posted February 11, 2009 Share Posted February 11, 2009 It won't catch fire, there's too much water around in the peroxide for a start..... You need more Arrow Root than Xanthan Gum and XG mixes in cold. You are aiming for the consistency of wallpaper paste or hair gel, a mixture that won't drip from a spoon, so it will cling to vertical surfaces. Quote Link to comment Share on other sites More sharing options...
Frotz Posted February 11, 2009 Share Posted February 11, 2009 What's the shelf life of this peroxide mixture, that is, how long before it decays into water? Quote Link to comment Share on other sites More sharing options...
Merlin Posted February 11, 2009 Share Posted February 11, 2009 For the gel as made up WITHOUT the Oxy added, it's stable and can be stored indefinitely, the shelf life will be as long as the original hydrogen peroxide. Once you add the Oxy to it, the reaction starts and you get 48 hours absolute maximum before the peroxide is all catalysed and spent. That's why we only add a tiny amount, so that we get a slow reaction over a longer time with less heat given off. Quote Link to comment Share on other sites More sharing options...
+selgus Posted February 13, 2009 Share Posted February 13, 2009 Well I got all the chemicals needed now, so this Sunday I am going to try the process on some 800XL and 1050 cases. I'll post some before/after shots too. --Selgus Quote Link to comment Share on other sites More sharing options...
Tempest Posted February 13, 2009 Share Posted February 13, 2009 If I don't seal the platic with a clear lacquer, how long will the yellowing stay away? Will it come back within a few months or are we talking 10+ years? Tempest Quote Link to comment Share on other sites More sharing options...
Merlin Posted February 13, 2009 Share Posted February 13, 2009 @ Tempest We are talking ten years at least... and you could always do the process again... Quote Link to comment Share on other sites More sharing options...
KLund1 Posted February 14, 2009 Share Posted February 14, 2009 All this is great info to clean up all those yellow cases. When this gets more out in the 'wild' I see a lot more Atari's up for sale the say 'mint', 'like new'!!! Question: Dose this formula work for the dark colors? I've read the whole post, and see nothing about the dark XL case parts. Pardon my missing knowledge, but aren't XL cases white (not beige), black around the keyboard, and brown keys? My 1200xl looks slightly brown around the keyboard. If I use the gel formula, will it turn back to black? Has anyone tried it. I'd rather not be the test subject. Next question; what is the 'right' kind of tape to use over the metal labels (just to be safe while painting with the gel)? Black electrical tape, light brown masking tape, clear office tape? The post was a bit vague. Thanks KLund1 Quote Link to comment Share on other sites More sharing options...
mimo Posted February 14, 2009 Author Share Posted February 14, 2009 (edited) the trim around the keys is dark brown.in my experience this part does not need treating,but you won't do any harm if you do.i would be wary of using any adhisve tape as you may pull off the print.I have done a few cases now, and have not damaged any decals.If you are worried i would just gently remove the decal before treating.Btw_xl cases are cream,just have a look at the inside of the case for the original colour. Edited February 14, 2009 by mimo Quote Link to comment Share on other sites More sharing options...
Merlin Posted February 14, 2009 Share Posted February 14, 2009 (edited) @ Klund1 Lorne at VCF treated a few parts that were meant to be dark blue but had gone a funny brown colour; when treated they went back to the original dark navy blue. Any pigments in the plastic are completely unaffected by the gel as long as you keep the strength of the hydrogen peroxide below 15%. Metal badges or painted decals shouldn't be affected as Mimo says. I would go for electrical tape for masking metal decals if you aren't sure as the adhesive isn't strong enough to lift the paint. Paper labels are obviously going to be toast after the process, so photograph or scan them first so that you can reproduce them if you need to later. Incidentally, this process was originally released just before Christmas; I am surprised at the lack of "mint, as new" machines on Fleabay, so it's not generally known out there yet. Edited February 14, 2009 by Merlin Quote Link to comment Share on other sites More sharing options...
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