The iconic Nintendo Entertainment System console occupies a special place in gaming history as one of the most popular and beloved systems of all time. For retro gamers and collectors, the classic grey and black NES with 8-bit games like Super Mario Bros. and The Legend of Zelda represent a definitive piece of childhood nostalgia.

However, one issue threatens the nostalgic appeal of vintage NES systems – the yellowing and discoloration of the plastic housing and components over time. Thankfully, dedicated retro enthusiasts have found effective do-it-yourself methods to restore an original NES case back to its former grey glory.

This guide will cover the required supplies, safe disassembly techniques, masking methods, applying hydrogen peroxide, curing under UV, reconditioning, and proper reassembly to transform a yellowed Nintendo NES to like-new condition using widely proven home retro restoration techniques. With some patience and care, your childhood NES can look as good as new again.

Overview of the Yellowing Problem on NES Consoles

When the Nintendo Entertainment System first arrived on the scene in North America in 1985, its striking angular grey plastic casing was an iconic part of the console’s identity. This was a contrast to the woodgrain paneling and faux wood finishes prevalent on computers and game consoles prior.

However, over decades, the ABS plastic blend used on the NES shell, controller deck, game cartridge tray, and components has a notorious tendency to undergo photochemical reactions from UV light exposure. This causes the normally light grey plastics to take on a yellow, yellow-orange, or even brown discoloration.

This unappealing aesthetic effect worsens over time without intervention. Left long enough, an original grey NES will turn almost completely yellow or orange. This plastic degradation not only impacts the exterior – internal plastic like cartridge loaders and frame braces also yellow significantly.

Thankfully, the yellowing does not necessarily affect the console’s working condition. But for collectors and those seeking to restore their childhood NES, the discolored look severely impacts the system’s vintage appeal and value.

Reversing this yellowing effect involves understanding the chemical reactions behind it. While not a perfectly reversible process, hobbyists have refined reliable techniques using hydrogen peroxide and targeted UV exposure to effectively “retrobright” yellowed plastics back to near-original condition.

Why Restore an NES Case?

For gaming enthusiasts with a yellowed Nintendo NES, restoring the system can breathe new life into a beloved part of childhood and provide great personal satisfaction. There are several motivations driving NES enthusiasts to retrobright their systems:

Improved Appearance

The most obvious reason is strictly cosmetic. Removing decades of yellowing simply makes the NES look good again. Seeing the console restored to its classic gray can be hugely rewarding, especially if you owned it as a kid.

Increased Value

Collectors know that a yellowed NES has significantly decreased display and resale value compared to a clean restored system. Retrobrighting improves monetary value for collectors.

Preservation

As these original systems age, restoring them helps preserve gaming history in better condition for future generations to appreciate.

DIY Satisfaction

Performing the restoration yourself using common household chemicals gives a huge sense of personal accomplishment.

Improved Functionality

In some cases, yellowed internal plastic can also deteriorate over time, so restoring could potentially improve functionality in addition to aesthetics.

These are all compelling reasons to consider taking the time and care to give an old discolored NES a new lease on life. The ability to reverse decades of yellowing is remarkable.

Required Tools and Materials

Restoring the plastic appearance of a Nintendo Entertainment System requires gathering some specific supplies together. Here are the required tools and materials for the process:

Hydrogen Peroxide Gel or Cream

The active ingredient for whitening the yellowed plastics is hydrogen peroxide. Standard 3% solutions found in pharmacies are too diluted. Instead, you need a thick gel or cream formula in 12% or higher concentrations:

• Retrobright Gel – Specifically designed for retro console restoring with thick consistency, 35% peroxide content and proprietary components. Highly recommended for best results, but costs more.
• Beauty Peroxide Creams – Some commercial teeth whitening gels and hair developer creams contain sufficiently high peroxide levels around 12-18%. Can work but runnier consistency.

Get enough gel to thoroughly coat all discolored plastic surfaces multiple times. Approx. 1-3 tubes or jars depending on system size.

UV Light Source

The hydrogen peroxide solution needs strong ultraviolet light exposure to trigger the chemical reaction that reverses yellowing. Two options:

• UV Lamp – A specialized 36-100 watt UV lamp bulb emits concentrated UV-A and UV-B light ideal for retrobrighting. This is highly recommended over sunlight.
• Sunlight – On very sunny days, direct natural sunlight provides UV-A exposure. Much slower and inconsistent than a UV bulb.

Reflective surfaces like aluminum foil can maximize UV exposure on all sides. Angle and rotate parts as needed.

Masking Tape or Vaseline

You’ll need to mask off plastic logos, text, and any parts you don’t want bleached bright white from peroxide overexposure. Options:

• Masking Tape – Use painter’s masking tape to cover off any text or logos. This protects dark plastics from lightening too much.
• Vaseline – An alternative is rubbing a thin layer of petroleum jelly onto any surface logos or text. Keeps peroxide gel off.

Make sure to cover any areas you want to remain original black or dark gray coloring.

Distilled White Vinegar

After bleaching, a dip in distilled white vinegar neutralizes and removes any residual peroxide activity. This stops the whitening chemical reaction.

Toothbrush and Dish Soap

Gently scrubbing with a soft toothbrush and dish detergent helps clean off gel residue and refine the surface after bleaching and vinegar baths.

Plastic Polish

After thoroughly drying all parts, applying a plastic polish with micro abrasives can restore the original glossy sheen to the now restored gray plastic.

Nitrile Gloves, Eye Protection

Wearing gloves prevents skin contact with peroxide gels. Safety glasses protect eyes from UV bounce. Work in a well-ventilated area.

Disassembling the NES Safely

Before applying peroxide gels and UV light, the NES console needs to be partially disassembled. This allows properly exposing and treating all yellowed exterior and interior plastic parts.

Disassembling a NES is not overly complex, but does require careful attention when handling the screws and plastic clips. Follow these steps:

Remove Cartridge Tray

The cartridge loading tray housing on the front of the NES is held in place by two small Phillips head screws at the bottom edges next to the controller ports. Using a screwdriver, remove these two screws and set them aside safely.

You can then gently pull the gray tray housing directly outwards away from the case – it should slide out intact to expose the metal cartridge insertion mechanism behind it. Detach the small pinned lever arm as well. Set all parts aside.

Open Case Halves

On the underside of the NES, remove the six large Phillips head screws that connect the top and bottom halves of the shell. One is under a sticker in the center.

Carefully separate the two case halves by wedging a flathead screwdriver or spudger tool into the seam and twisting gently to pop the internal clips free. Lift the top half of the case off and place it next to the bottom.

Remove Mainboard

The mainboard is secured to the bottom half of the case by two long Phillips head screws threaded into posts at the front edge near the controller ports. Remove these screws first, then proceed to carefully unclip and lift the motherboard out of the case bottom.

Detach the A/V and power cable connections from the mainboard as you lift it out. Place the mainboard aside carefully to avoid bending it.

Remove Metal Shielding

The majority of discolored plastics will now be accessible. But for full treatment, detach the metal RF shielding and heat sink plate from atop the motherboard by unscrewing them. This exposes all internal plastic frame braces and chassis tabs.

Set the metal shielding aside and inventory which plastic pieces can now be accessed for bleaching.

Applying Masking Tape and Vaseline

With the NES fully disassembled, the next phase is protecting areas you want to remain original black from being lightened by the peroxide. Use masking tape and/or vaseline:

Taping Text Areas

Referencing a stock photo of an original NES, note text areas like the molded “Nintendo Entertainment System” logo across the front. Apply strips of painter’s masking tape over the logo to block lightening.

Also mask off the “Power” and “Reset” text markings above the power switch on the deck. Check for any other text on the bottom or back you want to protect.

Rubbing Vaseline on Logos

For the iconic stylized red Nintendo logo on the case front, coat the raised plastic with a thin layer of vaseline using a small brush or finger. This prevents direct contact with peroxide.

You can alternatively use masking tape on logos if desired, but vaseline works well and blocks light.

Check Other Dark Areas

Survey for any other darker plastic regions or components you want to maintain original coloring on. Apply masking techniques as needed there.

Being thorough at this stage prevents over-bleaching and gives the best final results.

Preparing and Whitening Plastic Parts

With disassembly completed, logos masked off, and supplies gathered, you can now carry out the bleaching process using the hydrogen peroxide gel and UV light source:

Arrange Parts

Lay out all the yellowed plastic parts on sheets of aluminum foil in an area where they can remain undisturbed for many hours with ventilation. The foil will help reflect UV onto all surfaces.

Position parts so peroxide can fully contact them. Angle to avoid pooling in recesses.

Apply Peroxide Gel

Use gloves and eye protection for this step. Scoop a generous amount of hydrogen peroxide gel out of the container with a plastic knife or wooden popsicle stick. Apply a thick coat of gel evenly across all exterior surfaces of each yellowed part.

Spread the gel thoroughly into any cracks and crevices with a small wood or plastic spatula tool. Coat both the front and back of all components to maximize exposure.

Reapply peroxide across parts if initial coat gets absorbed too quickly. You want thick persistent coverage for proper bleaching.

Cure Under UV Light

Place the prepared parts under your UV light source at the optimal focal distance specified on your particular UV bulb fixture. This is often around 8-12 inches away from the parts.

Exposure times vary based on strength of UV output. Retrobright gel guidelines suggest curing for 12 hour blocks, with reapplication of peroxide 2-3 times during the cycle. Monitor progress every few hours.

With natural sunlight, consistent direct exposure over multiple days may be needed to see major lightening. Rotate and flip parts periodically to hit all surfaces.

Rinse Under Vinegar

Once satisfied with the degree of lightening after UV exposure cycles, thoroughly rinse all parts with distilled white vinegar to neutralize any remaining peroxide residue. Then rinse again with distilled water only.

Gently scrub with an old toothbrush if needed to remove gels. Dry parts fully with a microfiber cloth before reassembly.

Refining and Reassembling the NES

With the restoration bleaching process complete, the final steps are reconditioning the newly restored plastics, reassembling the console, and testing the final results:

Clean and Polish Parts

Use dish soap and a soft toothbrush to gently scrub each part, removing any remaining grime or whitening residue.

After drying, apply a thin coat of plastic polish to all exterior surfaces and buff lightly with a microfiber cloth. This restores gloss and smoothness.

Reattach Metal Shielding

Reposition the metal RF shielding and heat sink atop the mainboard and screw them back into place if removed earlier.

Reinstall Mainboard

Ensuring all cables are connected, lower the NES mainboard back into the bottom case half, aligning it properly with port openings. Reinstall the two Phillips screws through the mainboard’s mounting points.

Join Case Halves

Align the top case half over the bottom precisely and press together firmly. This will re-engage the internal plastic clipping.

Replace the six larger exterior Phillips screws to secure the halves together again on the underside.

Replace Cartridge Tray

Slide the front cartridge tray and lever arm assembly back into place until the tray sits flush. Then reinstall the two small Phillips screws at bottom corners to anchor it again.

Test Power On

Reconnect A/V cables and the power adapter to test that the newly retrobrighted console powers on and outputs video correctly. Insert a game cartridge to validate all functions operate properly after restoration.

Conclusion

Restoring the appearance of a yellowed Nintendo Entertainment System requires careful disassembly, preparation, whitening with peroxide/UV, and reassembly. But the proven techniques outlined here allow determined retro collectors to undo years of plastic degradation damage and revive nostalgic gaming hardware.

Taking the time to retrobright an original NES results in a dramatically refreshed system that looks factory new again, retaining the iconic styling that makes the console so enduring. The fully restored gray finish is testament to the power of harnessing chemical reactions to undo the toll of time.

Whether as a childhood memento or a collector’s centerpiece, giving an aged NES plastic shell a new lease on life offers great satisfaction. If done thoroughly and patiently, the final retrobrighted console will provide amazing results. Just be sure to handle chemicals safely and avoid overexposure.

With the right techniques and care, generations of gamers to come can continue appreciating the Nintendo masterpiece in its original, classic form thanks to DIY retro restoration.

FAQ

Is Retrobright the only solution for yellowed plastics?

Retrobright gel using peroxide and UV exposure is the most accessible and proven technique. Alternative approaches like ozone treatment have shown promise but require specialized equipment not readily available to most restorers.

How long does the bleaching process take to see results?

With concentrated peroxide gel and a UV lamp, lightening often becomes noticeable in a few hours. But plan on full treatments taking 10-15 hours of total UV exposure time across multiple rounds to maximize results. Have patience.

Will the yellowing eventually return after restoring?

Unfortunately yes, the ABS plastics can gradually re-yellow from new UV exposure and ambient heat. Periodic maintenance bleaching helps. Avoiding direct sunlight can slow the process.

What household items contain sufficiently strong hydrogen peroxide?

Some hair coloring kits and teeth whitening treatments contain peroxide gels around 12-18% concentration needed. But specialized retrobright formulas give better control for restoration.

Can I just use hydrogen peroxide cream and sunlight?

Sunlight is very inconsistent outdoors and can take weeks. Dedicated UV bulbs properly cure the peroxide gel much faster. But sunlight can work in a pinch given enough time.

Is there a way to prevent yellowing on an existing gray NES?

For long term storage, keeping the console away from heat, UV sources, and direct light will slow yellowing. But it cannot be fully prevented on ABS plastics given enough time.

What should I do if logos get bleached anyway despite taping?

Some lightening under tape edges or on logos is unavoidable over time. Touch up any affected dark plastic very carefully with small fine tipped permanent markers to darken again after bleaching is done.

Can I retrobright the plastic on SNES and other consoles too?

Yes, Genesis, SNES, Atari and other 80s-90s consoles also experience yellowing. The hydrogen peroxide and UV process works well on most ABS plastics given proper safety precautions.