The Case of the Yellowing White Bricks

justb1

thought I’d put this out there to see if anyone else experiencing the same issue as me. Firstly I’ll start by saying I’m neurotic about my lego Sets. For this reason I keep them sealed in their boxes when purchased until I can purchase a display case. Once built they go straight in the case and then on display, the case keeping them as dust free as possible. My problem has been of late that I’m noticing slight yellowing to a number of my white pieces, when I’m opening sets to build. The most recent in particular being the Creator Brick Bank. The 1x8 Bricks seemed particularly yellowed compared to the 1x6 bricks and other white parts. The white wall of the building looked awful when completed. Other sets seem to have tile pieces with similar issues, not so bad on their own but when put with other pieces very noticeable! It only appears to be certain parts within a set and not all. 

Now, is this some quality control issue at Lego’s end and white pieces are no longer as consistent as they used to be, for example my Sydney Opera House shows no signs of yellowing at all, and that’s even after being on display for nearly 4 years. Or is it in some way how I’m storing the boxes/sets until I build them. I live in the UK, so max temp at the moment prob about 30, and all my lego is kept either in a wardrobe or in my Lego room, which is kept dark with a blind down most times, but can get quite warm especially during the day. Surely white Lego can’t go yellow in a sealed box in UK temperatures or can it?? 

Just wanted to see other peoples views on white pieces or if anyone else has similar issues. I’m dreading opening my Roller coaster as that’s full of white pieces. 

Paperballpark

It's a very well known issue that some colours are susceptible to yellowing over time, and white is especially well known for that issue. It's happened for probably as long as there have been white Lego bricks.

As far as I can remember, the UV in sunlight triggers a chemical reaction in the bricks, which results in them yellowing. If I remember rightly, once they've been exposed to UV, that's it, the process is started, even if you keep them out of sunlight after that. I think the more they're exposed to UV though, the worse it makes it. Of course, I could just be talking out of my arse...

SumoLego

Anyone have issues with whitening yellow bricks?

Baby_Yoda

I've been having a similar problem with my grey bricks turning blue. Quality control just isn't what it used to be.

MAGNINOMINISUMBRA

I don't believe the issue your witnessing is anything at all to do with mid to long term UV degradation (ie yellowing).  I'm far more inclined to believe that what your dealing with is INITIAL opacity of the white bricks.  You will find that any brick  post 2003 will often be a varying shade of its base colour - yellow bricks are also notorious for this.  It's not uncommon for white to arrive fresh from thr factory in varying shades of cream/milky colour...
  People seem to have had varying degrees of success with TLG replacing creamy parts

MAGNINOMINISUMBRA

Baby_Yoda said:

I've been having a similar problem with my grey bricks turning blue. Quality control just isn't what it used to be.

I've got to concur - the B in LBG and DBG appears B'er than ever lately!
  While the B in DB doesn't... Go figure?

Pitfall69

^It scares me that what you posted makes total sense to me.

I'm glad you didn't post that your D appears B'er than ever lately ;)

Istokg

This problem has been discussed many many times before on all forums.  There never seems to be final concensus on what the issue or solution (besides Hydrogen Peroxide) is.

I have had new parts from 1979-80 USA Homemaker sets that have had the 1x6 and 1x8 bricks yellow much more quickly than other white bricks from that era (even from Homemaker sets).  20 years later those same parts get more tan in color, and the other white bricks stay white.

What makes blaming UV sunlight more problematic is the fact that some folks have suggested putting yellowed white parts into a sunny window for over a month.  I had some classic LEGO windows that were still in new conditioned but had yellowed.  I put them onto a sunny window ledge for 2 1/2 months... and they came out as pure white.  Now that makes no sense, if you ask me??

One chemical engineer I know mentioned to me that MRI (mould release agent) could be a contributing factor in when some parts exit their mould and soon start showing some yellowing.  I'm not an expert on that... so I don't really know.  But I do know that some parts that have never seen a single ray of sunlight... they also can yellow.

Baby_Yoda

MAGNINOMINISUMBRA said:

Baby_Yoda said:

I've been having a similar problem with my grey bricks turning blue. Quality control just isn't what it used to be.

I've got to concur - the B in LBG and DBG appears B'er than ever lately!
  While the B in DB doesn't... Go figure?

Well, I was just kidding, since grey bricks used to be just grey but then Lego started mixing them in with a bit of blue. Colours in general are starting to become badly inconsistent. I've heard that none of the sand green bricks in #21136 Ocean Monument are actually the same shade of sand green...

SumoLego

Pitfall69 said:

I'm glad you didn't post that your D appears B'er than ever lately ;)

You put the 'D' in DB. 

(@Legoboy actually does, but he's really not part of this conversation.  Which I am really not part of, either.)

MAGNINOMINISUMBRA

Pitfall69 said:

^It scares me that what you posted makes total sense to me.

I'm glad you didn't post that your D appears B'er than ever lately ;)

It was BYG at one stage...
Turns out that's NOT a good thing!

MAGNINOMINISUMBRA

Baby_Yoda said:

MAGNINOMINISUMBRA said:

Baby_Yoda said:

I've been having a similar problem with my grey bricks turning blue. Quality control just isn't what it used to be.

I've got to concur - the B in LBG and DBG appears B'er than ever lately!
  While the B in DB doesn't... Go figure?

Well, I was just kidding, since grey bricks used to be just grey but then Lego started mixing them in with a bit of blue. Colours in general are starting to become badly inconsistent. I've heard that none of the sand green bricks in #21136 Ocean Monument are actually the same shade of sand green...

I didn't realise you were joking due to lack of wonky faces (and possible over medication). But brick opacity is IMO at least actually quite sad and NOT a laughing matter.  Sand green is DEFINITELY one of the top culprits - if you too want to make yourself sad, put an Ocean Monument or an Old fishing Store next to an ORIGINAL Statue of Liberty.  When I think of the increase in costs over the years versus the decrease in uniformity, it almost moves from saddening to angering!

MAGNINOMINISUMBRA

Istokg said:

This problem has been discussed many many times before on all forums.  There never seems to be final concensus on what the issue or solution (besides Hydrogen Peroxide) is.

I have had new parts from 1979-80 USA Homemaker sets that have had the 1x6 and 1x8 bricks yellow much more quickly than other white bricks from that era (even from Homemaker sets).  20 years later those same parts get more tan in color, and the other white bricks stay white.

What makes blaming UV sunlight more problematic is the fact that some folks have suggested putting yellowed white parts into a sunny window for over a month.  I had some classic LEGO windows that were still in new conditioned but had yellowed.  I put them onto a sunny window ledge for 2 1/2 months... and they came out as pure white.  Now that makes no sense, if you ask me??

One chemical engineer I know mentioned to me that MRI (mould release agent) could be a contributing factor in when some parts exit their mould and soon start showing some yellowing.  I'm not an expert on that... so I don't really know.  But I do know that some parts that have never seen a single ray of sunlight... they also can yellow.

While every single point you've made there is correct Gary (a mate of mine who is a Moulder shares a similar theory regarding MRA's (and, as an aside has also shown me the difference in tensile moulded strength in ABS (ie- cracking)  that a two degree environmental temperature difference can make to exactly the same part but that's another story))  I'm still 99.99% sure that due to the sets mentioned, what @justb1 is referring to is opacity issues.  The most ENTIRELY frustrating part about this is that TLG MOST DEFINITELY CAN FIX THIS ISSUE as it is ENTIRELY measure able (and therefore correctable) at time of manufacture (and if they say it isn't - they're lying).  
 I accept that UV degradation and long term cracking are a lot harder to fix, but if they consistently DONT fix something they can what are the real chances of them fixing something they MIGHT be able to?

Astrobricks

FWIW, I just finished building #21042 (great build!) and the hundreds of sand green parts are very consistent.

Switchfoot55

From what I recall, the recent #40178 VIP Set Polybag had similar issues of yellowing to the white bricks just after they were shipped. Unless they were filling bags from the open old shoe boxes out back in the parking lot, they were brand new bricks that seemed very yellow compared to other smaller white parts in the set. 

It leads me to believe it's just a quality issue of the original materials as discussed above.

MAGNINOMINISUMBRA

Astrobricks said:

FWIW, I just finished building #21042 (great build!) and the hundreds of sand green parts are very consistent.

That's a great observation - and I AM really interested to hear that!  I'd been  wondering since the set was announced what the the uniformity of bricks would be like as it would have looked freaking horrible if it was as hodge podge as some of the earlier sets mentioned.  Your observation also adds credence to my earlier statement that uniformity is an ENTIRELY controllable QC issue.

MAGNINOMINISUMBRA

Switchfoot55 said:

From what I recall, the recent #40178 VIP Set Polybag had similar issues of yellowing to the white bricks just after they were shipped. Unless they were filling bags from the open old shoe boxes out back in the parking lot, they were brand new bricks that seemed very yellow compared to other smaller white parts in the set. 

It leads me to believe it's just a quality issue of the original materials as discussed above.

Maybe it's just a regional/ language issue but once again, this ISNT 'yellowing'.
New, post 03 bricks don't initially suffer from yellowing - they suffer from opacity issues.  Opacity is an issue which TLG could, if they so wished, fix tomorrow and fix permanently.  Yellowing/ UV degradation is a much more complicated and time depemdant issue. If they won't fix something the CAN fix immediately, they're unlikely to fix something that takes time and research!

Astrobricks

MAGNINOMINISUMBRA said:

Astrobricks said:

FWIW, I just finished building #21042 (great build!) and the hundreds of sand green parts are very consistent.

That's a great observation - and I AM really interested to hear that!  I'd been  wondering since the set was announced what the the uniformity of bricks would be like as it would have looked freaking horrible if it was as hodge podge as some of the earlier sets mentioned.  Your observation also adds credence to my earlier statement that uniformity is an ENTIRELY controllable QC issue.

Or... they just all happened to come from the same batch.

MAGNINOMINISUMBRA

 Possibly, though hat many individual bricks , from that many seperate moulds would require a gigantic load of post mix pellets to so.  The chance that it's random is close to non existent!  This leads us back to the fact they COULD have applied the QA necessary to ensure it happened and, if so, why can't that same level of care be applied uniformly across other single colour intensive sets?

Astrobricks

Real life isn’t perfect. Maybe TLG is embracing imperfection :)

Baby_Yoda

MAGNINOMINISUMBRA said:
I didn't realise you were joking due to lack of wonky faces (and possible over medication).

Yeah... that tends to be an issue for me on any forum, and with some people in real life too who can't quite detect sarcasm in tone.

MAGNINOMINISUMBRA

Astrobricks said:

Real life isn’t perfect. Maybe TLG is embracing imperfection :)

I'm TOTALLY cool with that...
as long as they're charging me accordingly!

Cyberdragon

If they had an injection molding system that kept the plastic molten in a heated vat (with mixers) instead of solid pellets that melt right before being pumped into the injectors, a computer could monitor the exact color and add colors as needed to keep it consistant. You could feed alot of injectors off of the same vat of plastic and have them all exactly the same color. Or you could turn the plastic back into pellets and feed them into standard injectors.

If a system like that doesn't exist (I haven't found any heated ABS mixers yet), you could make a lot of money patenting it and selling it to companies like Lego.

Pitfall69

So, I did a little experiment with my "yellowed" classic gray pieces. I soaked the 2 "clean" pieces in just regular strength Hydrogen Peroxide and left outside in the sun for 1:30. The piece to the left is what they looked like before. I also did the same with 2 more pieces and the result was the same. I put 2 other pieces in the same solution, but this time, under a UV bulb used to sterilize equipment. The pieces have been under the lamp for 2 hours and there hasn't been a significant change. There is more to sunlight than just UV radiation. Maybe it is the combination of all the suns radiation mixed with the hydrogen peroxide that takes away the "yellowing" of the pieces. It obviously is not an exact science. The UV bulb doesn't seem to be working as well, so I am just going to use the power of the sun from now on.

Astrobricks

^ Maybe a UVA vs. UVB thing?

Astrobricks

MAGNINOMINISUMBRA said:

Astrobricks said:

Real life isn’t perfect. Maybe TLG is embracing imperfection :)

I'm TOTALLY cool with that...
as long as they're charging me accordingly!

You probably don’t want to know what they’d charge you for perfection :)

MAGNINOMINISUMBRA

@Pitfall69
its definitely going to be an incredibly complicated equation involving specific grades of light at specific wavelengths and all that sort of jazz. I'd also be suprised if the exact same experiment, performed under the exact same conditions at differing latitudes, altitudes and times of the day and year didn't yield a different set of results. Thanks for the pics - I always enjoy looking at the different results people can get!

MAGNINOMINISUMBRA

Cyberdragon said:

If they had an injection molding system that kept the plastic molten in a heated vat (with mixers) instead of solid pellets that melt right before being pumped into the injectors, a computer could monitor the exact color and add colors as needed to keep it consistant. You could feed alot of injectors off of the same vat of plastic and have them all exactly the same color. Or you could turn the plastic back into pellets and feed them into standard injectors.

If a system like that doesn't exist (I haven't found any heated ABS mixers yet), you could make a lot of money patenting it and selling it to companies like Lego.

Don't quote me but I think the main reason such systems don't exist is due to temperature/pressure variances in the  injection process.  The Moulder I know says that all cracking and strength issues stem from pressure/temperature variances (sometimes less than a single degree of difference can ruin a job.  The easiest way is simply to go back to the old system of ALL pellet colours being pre mixed.  While its pretty obvious that the entire process is cost driven, it's impossible to believe we can't replicate or exceed the results of half a century ago.

MAYBE... 
TLG are aware that general consumers just don't give a fig while us 'junkies' will constantly tolerate decreases in quality so long as we're still getting our fix?

omnium

Astrobricks said:

FWIW, I just finished building #21042 (great build!) and the hundreds of sand green parts are very consistent.

I recently parted out and Old Fishing Store and a Monument set. Both sets had two shades of Sand Green, approximately a 50/50 mix.

The lighter ones from both sets are the same shade and the darker ones also match. (Not sure I explained that very well...)

I've ended up with a collection of light Sand Green bricks and dark Sand Green bricks.

I had the same with a PaB cup of LBG profile bricks: 2 shades, not many shades.

And my TLM dropship had a selection of white 2x2 inverted slopes, half of which were white, the other half pink.

Pitfall69

There was discussion about the different shades of of Sand Green when the Haunted House came out. The Sand Green in the Green Grocer is definitely lighter than the HH Sand Grren. 

MAGNINOMINISUMBRA

^ And from my personal experience the Green Grocer Sand Green is the same as the ORIGINAL Statue of Libety. (With no defined difference in shade)

Cyberdragon

MAGNINOMINISUMBRA said:

Cyberdragon said:

If they had an injection molding system that kept the plastic molten in a heated vat (with mixers) instead of solid pellets that melt right before being pumped into the injectors, a computer could monitor the exact color and add colors as needed to keep it consistant. You could feed alot of injectors off of the same vat of plastic and have them all exactly the same color. Or you could turn the plastic back into pellets and feed them into standard injectors.

If a system like that doesn't exist (I haven't found any heated ABS mixers yet), you could make a lot of money patenting it and selling it to companies like Lego.

Don't quote me but I think the main reason such systems don't exist is due to temperature/pressure variances in the  injection process.  The Moulder I know says that all cracking and strength issues stem from pressure/temperature variances (sometimes less than a single degree of difference can ruin a job.  The easiest way is simply to go back to the old system of ALL pellet colours being pre mixed.  While its pretty obvious that the entire process is cost driven, it's impossible to believe we can't replicate or exceed the results of half a century ago.

MAYBE... 
TLG are aware that general consumers just don't give a fig while us 'junkies' will constantly tolerate decreases in quality so long as we're still getting our fix?

Temperature and pressure in the mold would still be regulated by the internal heaters. The fluid plastic would be slowly cooling naturally as it flows down the pipes so it would have to be reheated in the injectors anyway (although only a small amount so they would be lower power heaters), so the temperature can be adjusted precisely in the injectors.

Exactly, I think we need to move on an invent new and better systems for plastics. In fact, the plastics are often remelted and recycled from the "sprues and runners" of the mold. There's no reason they couldn't mix the colors while melted before putting them into the mold (either solid or liquid). Once somebody pitches a better system to the industry, people will realize how bad the old way is.

"Robots"  the movie: "Why be you, when you can be NEW?!"

Pitfall69

I have now succesfully soaked and lightened about 30-40 plates. One thing is for sure; if there aren't a lot of bubbles, it isn't working well enough. I have placed parts in a Hydrogen Peroxide solution without any sunlight and while there were some bubbles, there wasn't close to the amount of bubbles that there are when you place the parts in the sunlight. I'm not a chemist, but there has to be some sort of chemical process taking place.

pxchris

Pitfall69 said:

I'm not a chemist, but there has to be some sort of chemical process taking place.

*insert aliens meme here*

Pitfall69

"Get away from my meme you B**ch!!!" ;)

eggshen

I just opened up some sealed 2014 City Arctic sets and some of the white pieces are definitely more yellowish than other pieces in the same sets. So if the problem is not with the ABS but is actually with the mold release agent that might explain why some of us are seeing yellowing but others are not. It would also explain why there are different experiences with displaying. I have other pieces that have been on display for a long time with issues, but other pieces that have never seen the light of day (literally) that are yellowed. 

Has anyone ever cut apart a yellowed piece to see if the exposed surface yellows? That would be a worthy experiment to see if the internal ABS reacts to light. 

Bumblepants

I probably posted this before but...

Parts I repaired back to bright white via the hydrogen peroxide method returned back to their yellowed state while in a climate controlled, completely dark closet. The return to the yellowed state happened in roughly two years time.

So while I was initially very pleased with the result, I no longer will be bothering to try and whiten bricks or more to the point, I won't buy used bricks anymore.

Astrobricks

eggshen said:

I just opened up some sealed 2014 City Arctic sets and some of the white pieces are definitely more yellowish than other pieces in the same sets. So if the problem is not with the ABS but is actually with the mold release agent that might explain why some of us are seeing yellowing but others are not. It would also explain why there are different experiences with displaying. I have other pieces that have been on display for a long time with issues, but other pieces that have never seen the light of day (literally) that are yellowed. 

Has anyone ever cut apart a yellowed piece to see if the exposed surface yellows? That would be a worthy experiment to see if the internal ABS reacts to light. 

Has anyone tried whitening the yellowish white pieces from a newly opened set? 

Cyberdragon

Has anyone tried storing them in a vacuum? Maybe it's oxidation. A vacuum chamber would be ideal but a kitchen vacuum packer/sealer might also work. They might still turn a little bit due to remaining air but hopefully much less, and hopefully the bag lasts that long without leaking.

NOTE: Not responsible for your pieces getting worse, swelling, turning to dust, or any other strange occurances.

MAGNINOMINISUMBRA

eggshen said:

I just opened up some sealed 2014 City Arctic sets and some of the white pieces are definitely more yellowish than other pieces in the same sets. So if the problem is not with the ABS but is actually with the mold release agent that might explain why some of us are seeing yellowing but others are not. It would also explain why there are different experiences with displaying. I have other pieces that have been on display for a long time with issues, but other pieces that have never seen the light of day (literally) that are yellowed. 

Has anyone ever cut apart a yellowed piece to see if the exposed surface yellows? That would be a worthy experiment to see if the internal ABS reacts to light. 

Once  again,  
Are you sure that what you're describing as 'yellowing' is not actually an opacity issue?  In my experience, there's a world of visible difference between the milky, creamy, pinky or yellowy new,post mixed,  post 04 bricks and bricks that are Yellowed from exposure to UV/ sunlight.

Switchfoot55

Cyberdragon said:

Has anyone tried storing them in a vacuum? Maybe it's oxidation. A vacuum chamber would be ideal but a kitchen vacuum packer/sealer might also work. They might still turn a little bit due to remaining air but hopefully much less, and hopefully the bag lasts that long without leaking.

NOTE: Not responsible for your pieces getting worse, swelling, turning to dust, or any other strange occurances.

My son's Lego are unintentionally stored in a vacuum on a weekly basis. But after inspecting, they mainly just come out more dusty than anything. 

Istokg

I cannot say if storing LEGO in a vacuum (chamber) will reduce the yellowing... but there is on effect that it will do.  For LEGO parts that have picked up the odor of a "smokers household", at least 24 hours in a  vacuum chamber will eliminate the smoke smell.  It is the Butadiene of ABS plastic that absorbs the smoke smell, and at least a day in a vacuum chamber will eliminate that smell.

Cyberdragon

My Lego has surely picked up the smell of fried electronics then...

Astrobricks

Istokg said:

I cannot say if storing LEGO in a vacuum (chamber) will reduce the yellowing... but there is on effect that it will do.  For LEGO parts that have picked up the odor of a "smokers household", at least 24 hours in a  vacuum chamber will eliminate the smoke smell.  It is the Butadiene of ABS plastic that absorbs the smoke smell, and at least a day in a vacuum chamber will eliminate that smell.

I gotta ask; was this approach planned, or discovered somehow by chance?

Istokg

Astrobricks said:

Istokg said:

I cannot say if storing LEGO in a vacuum (chamber) will reduce the yellowing... but there is on effect that it will do.  For LEGO parts that have picked up the odor of a "smokers household", at least 24 hours in a  vacuum chamber will eliminate the smoke smell.  It is the Butadiene of ABS plastic that absorbs the smoke smell, and at least a day in a vacuum chamber will eliminate that smell.

I gotta ask; was this approach planned, or discovered somehow by chance?

No, I have an acquaintance who is a chemical engineer, and after a lengthy discussion about the properties of ABS plastic (LEGO specific)... the discussion sort of sidetracked to "smoky LEGO"... and his comments on which molecules retain the smoky smell, and how to eliminiate it.  He was also the one who suggested to me that the MRA... mold release agent... might be a main culprit responsible for the yellowing of LEGO parts.

MAGNINOMINISUMBRA

Cyberdragon said:

My Lego has surely picked up the smell of fried electronics then...

Mine is more likely to be fried chicken...

MAGNINOMINISUMBRA

Istokg said:

Astrobricks said:

Istokg said:

I cannot say if storing LEGO in a vacuum (chamber) will reduce the yellowing... but there is on effect that it will do.  For LEGO parts that have picked up the odor of a "smokers household", at least 24 hours in a  vacuum chamber will eliminate the smoke smell.  It is the Butadiene of ABS plastic that absorbs the smoke smell, and at least a day in a vacuum chamber will eliminate that smell.

I gotta ask; was this approach planned, or discovered somehow by chance?

No, I have an acquaintance who is a chemical engineer, and after a lengthy discussion about the properties of ABS plastic (LEGO specific)... the discussion sort of sidetracked to "smoky LEGO"... and his comments on which molecules retain the smoky smell, and how to eliminiate it.  He was also the one who suggested to me that the MRA... mold release agent... might be a main culprit responsible for the yellowing of LEGO parts.

This is possibly the coolest piece of LEGO refurbing info I've heard.  As usual -  thanks Gary!

Pitfall69

Update:

What I have been trying to do is restore my UCS Star Destroyer and the first part was to fix the classic light gray/grey that has turned color over the years. I had it displayed and it was definitely exposed to sunlight and florescent bulbs. 

I have now successfully lightened and cleaned over 1900 parts. The most expensive parts showed no signs of discoloration, so I didn't soak them. I have only used 6 bottles of peroxide and what I found was that you can reuse the peroxide at least 3 times without any visible issues. I dont know how many times you can reuse the solution before it loses it potency.

To me; it is definitely worth the time to lighten the parts because it saved me a lot of time trying to order an estimated 2000 Classic Light Gray pieces on Bricklink and there was a significant cost savings in that each piece cost anywhere from $0.05-1.30. I used and average of 0.15 with shipping included a piece for my calculations and came up with a cost of $300 to replace 90% of the parts. Each bottle only cost $1.00. So, besides the cost and dealing with Bricklink, it is also reassuring to me that these are the exact parts that came with my set and you cant put a price on that piece of mind :)

piratemania7

^thats a peace of excellent news.

Pitfall69

^Yes, and "piece" of mind was a pun ;) 

...and also an Iron Maiden Album 

Cyberdragon

Oh dear!

My #7470 has yellowed all to hell! (I thought it was just dirty) It appears to be mosly UV damage as the inside doesn't look that bad, but you can see where the yellowing has seeped through the pieces. One of the 2x10s on top has gone almost orange all the way through, and the other one is getting there. RIP the remaining stickers come soaking time. (I might find replacements)