Fixing loose clutching bricks

[super curry max]

the pieces that have lost their grip.

I won an auction on ebay for a few sets(sheriffs lock-up, bandits secret hideout, renegade runner, broadsides brig, and wavemaster) for a great price of $55. A lot of the pieces from the 2 pirate sets are like this. I don't get how this happens as I have bricks from the mid 80s that are still as grippy as ever but there you go.

[CP5670]

I don't know exactly what causes this or how to fix it. It might be temperature related.

I have gotten a few sets like this from ebay too. The strangest case was a 6990 that looked practically new (it was advertised to have been opened recently and built once) but had very weak clutch power on most of the bricks. Some 1x2 plates were so weak that they came apart simply under gravity. I've also gotten other sets with the opposite issue, with exceptionally strongly gripping bricks (some of which were MISB).

[super curry max]

I don't know exactly what causes this or how to fix it. It might be temperature related.

I have gotten a few sets like this from ebay too. The strangest case was a 6990 that looked practically new (it was advertised to have been opened recently and built once) but had very weak clutch power on most of the bricks. Some 1x2 plates were so weak that they came apart simply under gravity. I've also gotten other sets with the opposite issue, with exceptionally strongly gripping bricks (some of which were MISB).

I hope it isn't hot temperature. I wash every brick/set i buy used in hot soapy water because i'm a bit of a germophobe but also because they are usually caked in dust. I hope the water didn't do that to them. :(

Though I havn't noticed this with any other bricks I've bought and washed.

[Superkalle]

I had the fortune and pleasure to talk to a few TGL designers at one time, and was told that TLG themselves use an "oven test" to test model design. This means that they heat all models to 60-70 degrees for many hours. Excessive heat makes the plastic shrink a tiny amount. They do this oven-test to verify how well a model will hold together when being played by kids (i.e. a way to identify weak spots in the design). In other words, excessive heat will make the pieces loose their clutch power because of plastic shrinkage.

I had a talk to a professor of Polymer Materials some time ago, and he said that part of the explanation is the butadien (rubber) componentn in ABS that will make bricks shrink ever so slightly. Compare to an old rubber band and see how it becomes brittle and dry over time. Of couse this process is much, much slower in ABS then in rubber; but it occurs to some extent.

So in SuperCurrys case, it may have been that the Lego had been exposed to high temperatures of a longer period of time. Perhaps the LEGO was left in the trunk of a car or similar for days?

Then there is another intresting aging process in Lego bricks that is worth mentioning, and that is INCREASED clutch power due to increaseed surface friction. This is caused by molecular changes in the surface structure over time. At TLG they have huge shelfs with drawers of Lego-bricks used by designers to build models. This Lego is replaced every 5 years or so because the clutch power increases over years - older brickcs become more "squeaqy" when put together. And once again, designers do not want Lego bricks that hold together in a way that is not representative of how the bricks act out of the box. However, heating bricks in the "oven test" will make them shrink more than the friction increases.

Hope that helpes somewhat. Naturally there may be other causes for shrinkes, for example if the Lego was exposed to various chemical agents, but the first thing that comes to mind is the heat.

Trivia - regarding the oven test, TGL ran in to troubles when they wanted to test the UCS Millenium Falcon. Their test oven was simply to small. So they called a local Pizza-place and borrowed their oven. Funny but true

[Tycho McKorley]

Thank you for your insights on this. I have wondered about this issue for some time and you have explained a lot of it to me.

Trivia - regarding the oven test, TGL ran in to troubles when they wanted to test the UCS Millenium Falcon. Their test oven was simply to small. So they called a local Pizza-place and borrowed their oven. Funny but true

Hah, that's actually a pretty funny story. I think the test scenario was unrealistic anyway though because I doubt too many children bought or acquired such an expensive set. AFOLS, the ones who really probably wolfed down that set, probably don't expose their Lego to so many temperature extremes.

[fred67]

I've noticed (anecdotal evidence) that after cleaning old white and gray pieces with hydrogen peroxide and oxyclean (retrobright minus the thickeners), that the surfaces of the pieces seem a bit more grippy, I think it may slightly expand the surface.

One of the reasons why it messes up clear pieces when I try it... the clear pieces end up being better than they were (not yellowed) but they lose the shininess... I think the process "roughs up" the surface.

[Superkalle]

Thank you for your insights on this. I have wondered about this issue for some time and you have explained a lot of it to me.

You're welcome

I've noticed (anecdotal evidence) that after cleaning old white and gray pieces with hydrogen peroxide and oxyclean (retrobright minus the thickeners), that the surfaces of the pieces seem a bit more grippy, I think it may slightly expand the surface.

I would assume that this is more because that all residue/grease/dust on the studs and anti-studs* are cleaned (I mean with hydrogen peroxide you get a VERY clean surface).

Regarding yellowing of plastic, the above mentioned professor said: When plastic comes into contact with oxygen and UV-light, a degradation begins that results in a increasing discoloration. The discoloration is a results of double bindings being created in the polymer chains, so that a series of single- and double bindings absorb the blue light in the spectrum, thus making the plastic look yellow.

So what does this mean for us Lego-nerds? Keep the Lego away from direct sunlight and excessive heat, but we already knew that

*) Anti-studs: Internal TGL lingo for the cavities where....well, the studs go. And to be completely true, TLG actually call it knobs and anti-knobs, I guess it feels more natural to them since a stud in Danish is called a "knobb".

[CP5670]

I had the fortune and pleasure to talk to a few TGL designers at one time, and was told that TLG themselves use an "oven test" to test model design. This means that they heat all models to 60-70 degrees for many hours. Excessive heat makes the plastic shrink a tiny amount. They do this oven-test to verify how well a model will hold together when being played by kids (i.e. a way to identify weak spots in the design). In other words, excessive heat will make the pieces loose their clutch power because of plastic shrinkage.

Excellent post. That explains a lot of things we've seen with this.

I have especially noticed the increase in clutch power on sets from the late 80s. Most of the MISB sets I got off ebay from that era had very strongly clutching and "squeaky" bricks, to the extent that the colors from different pieces slightly rubbed off on studs, but the bricks returned to normal over time if the model was left built up. Some of these sets also had the smoky/yellowed bricks discussed here, although I don't know if there is any connection.

On the other hand, I haven't seen this on any used sets I have from the same time period. In fact, they tend to have the opposite issue with weak clutch power, even if they are kept away from UV light and under a controlled temperature. This may be simply caused by leaving the bricks connected, which also reduces their clutch power over time. I think this happens at a faster rate than they gain clutch power by simply aging.

Edited August 24, 2010 by CP5670

[gotoAndLego]

Trivia - regarding the oven test, TGL ran in to troubles when they wanted to test the UCS Millenium Falcon. Their test oven was simply to small. So they called a local Pizza-place and borrowed their oven. Funny but true

Weird that they could test the UCS Star Destroyer but not the UCS Falcon.

[The Legonater]

Trivia - regarding the oven test, TGL ran in to troubles when they wanted to test the UCS Millenium Falcon. Their test oven was simply to small. So they called a local Pizza-place and borrowed their oven. Funny but true

Actually, they called a local sauna.

[Superkalle]

Actually, they called a local sauna.

I heard about the Pizza oven from a designer in Billund when we were there with the EB event this spring. Where did you get your information about the sauna?

[naf]

In some of my older Lego sets, a few of the bricks have lost their "connective strength," ie they don't stick together as well as they used to. I'm assuming this is caused by regular play wearing the plastic around the studs out. This seems to be most common with 1 stud pieces, like the 2x1 brick with 1 stud on top. I've also noticed this with a number of my older minifigures. My pirate captain's bicorn hat doesn't stay on his head very tight, it doesn't have that "snap" when you put it on, and a light breeze can knock it off. Also, some of the hands from my minifigures are rather loose and come out easily. Is there any reliable way to fix this? I thought about maybe putting a light dab of clear nailpolish on the inside of the pirate hat, for instance, so that there's more stuff for the head stud to grab onto. I could simply replace some of these pieces, but since they'll most likely be used there's no guarantee that they'll be better.

Thanks in advance!

[Spitfire2865]

Well, With hands, I usually find that the problem is either a crack in the arm or the ridge on the peg of the hand is worn down. If the arm isnt cracked, changing the hand might help. Or changing the arm. Either way that problem should be fixed.

I wouldnt put anything on the loosened parts. Maybe for the long run, getting replacements would be best. Yes they probably would be used, but you just have to hope it wasnt used Too much.

Hope this helps a bit.

[naf]

Doesn't look like the minifigure arms are cracked, so it must be that the hand is worn down. I'll probably just look into replacing the bricks and minifigures.

[Grimmbeard]

I've noticed this with hats as well, especially the bicorn. I guess it just comes down to wear and tear. Some old bricks just don't work the way they used to .

[naf]

I came up with an easy solution for the bicorn - I cut a little piece of plastic (bubble wrap, saran, whatever you have on hand) and stuffed it into the bicorn. The added material creates a nice tight fit.

[Fugazi]

There was some discussion here: Fixing loose clutching bricks, but without a real answer. Clear nail polish can certainly help, although you may need to replace it as it wears off.

[kibosh]

In some of my older Lego sets, a few of the bricks have lost their "connective strength," ie they don't stick together as well as they used to.

Were your older bricks left connected for a long time? In other words, did they sit as a built model for an extended period of time? Bricks do lose some of their clutch power when put together too long. It's like it stretches the plastic.

[naf]

Were your older bricks left connected for a long time? In other words, did they sit as a built model for an extended period of time? Bricks do lose some of their clutch power when put together too long. It's like it stretches the plastic.

I'm not sure, the problem bricks are from sets I've bought used on the secondary market. I've read that about that happening to bricks that are stored connected, but I also read that if you leave them unconnected they could go back into their original shape in time, might be something I'll try.

Like I said, most of the problems are with 1 stud bricks, which never seem to clutch the greatest anyway, even when new.

[TheLegoDr]

I've actually heard that keeping bricks clutched for too long will actually make them clutch stronger over time. It is logical that it could stretch the plastic though, but I've heard differently. I've never actually tested the theory though. I do have my King's Mountain Fortress set built for probably close to 20 years, but I haven't checked to see how clutchable they are. Granted it would probably end up being different plastic used, so the results wouldn't really change anything.

As far as not sticking like they used to, well that happens with everything. I have plenty of new bricks that don't stick that well and plenty of new bricks that do (same goes for older 15+ years) the same.

I agree about hands, usually there is a crack somewhere, although I have some older minifigures with loose arms, but not visible cracks. So it's tough to say.

[Hrw-Amen]

Some of my bricks that were put away stacked in rows of ten for many many years are more or less stuck together. I had to really put a lot of effort into getting them apart. Once they were seperated though I could use them as normal. So in my experience the longer they are together the harder it becomes to get them apart, as opposed to easier.

[naf]

Upon inspecting the bricks, it looks like some have hairline fractures that are causing them to not grip well. Same with the minifigures, I'll probably just end up replacing the damaged parts.

[Sylvarsty]

Its not a permanent fix but you could use some of that tack that is used to put up posters. It works pretty well if you're OK with it not fitting exactly right.

[Captain Green Hair]

I have experienced this in some of my older (and rarer) pieces, but due to their value I can't just throw them out.

So I simply put a bit of tape over the stud (invisible in clutch) and they work again.

[Adam87]

Hi,

I got questions,

When I build a set and decided to leave the set build/assembled on my shelf. How long set can be build/assembled before bricks start loosing cluth power ?

assembled bricks in long term provides to loosing cluth power ?