Mold anomaly or different pin?

[nerdsforprez]

There has been a lot of chatter as of late in building Technic models with high-strength needs in mind. Whether you are building big (i.e. lots of weight), want faster cars and trucks and are planning on using RC components, lift a lot of weight with crane or truss, keeping Lego pieces together is an absolute must.

I am currently also working on such a project with high-strength needs. This morning while building, i came across something weird.

Now.... the top pins are obviously thicker and more robust than the bottom pins. Notice how thin the plastic is on those pins displayed in the bottom row. Now, to my knowledge, there are two kinds of pins, but only two kinds. A quick look on bricklink confirms this. Ones with slots in the middle and ones without such slots.

Now..... the ones that are displayed in the pic up top both have slots!

but.... as seen, the thickness of the plastic is so much different. The visual helps us see this, but to make sure our eyes are not deceiving us simple demonstration confirms this:

I toyed with both pins this morning and the thicker are obviously stronger. Much much stronger. If I found enough I would create some experiment to demonstrate this. I searched throughout my inventory this morning and out of probably 5-600 pins only found 12 like this. My question for the forum is Does this represent a new part altogether or is it some anomaly in a mold or something? There has been criticism of TLG in the past few years of using less and less plastic in their molds...... is this just evidence of this? I have really only been building and collecting since 2012.....so it is not like I have any (or at least don't think so..... I have collected some sets from others that date back a decade or so) or lots and lots or really old pieces.

If these are just older pieces and represent the less plastic used by TLG..... then I think it is worth mentioning that if you are building a project that requires a lot of strength.... look through your own collections and see if you can't find the thicker pins. 3L pins are already much thicker....... so mentioning that is kinda a moot point......

[Epic Technic]

I believe that it is just an older pin, it looks like one from the older studded technic era.

[nerdsforprez]

If so I am surprised I have not heard about this before on the forum. It seems to me then..... that (if this is truly the case) it would be in certain people's best interest (mine included) to stockpile these guys. Like I mentioned... they are lots stronger. This would make for an interesting philo-like test......

[dr_spock]

The older pins were thicker if recall. They required lots of finger strength to pull out which is not good for builders with arthritis. I came across two in my collection that wouldn't come out even after pulling with pliers.

[TechniChriS]

i have a few of the thicker ones.

Didn't even know it untill I used some while working on the front of the B-model of the Arocs truck.

The flick pins on which you mount the plates of the grille don't fit in the thicker pins.

61184 http://alpha.bricklink.com/pages/clone/catalogitem.page?P=61184

Edited September 26, 2015 by TechniChriS

[BusterHaus]

I don't think these are the friction pins we saw 20 years ago, as those didn't have slots in the middle. Maybe something more recent. Here's a comparison of a 20 year old one with a new one, and one that I think comes from a Megablocks set:

You can tell by the tooth marks on the old friction pin that they are very hard to remove, like dr_spock said.

[Erik Leppen]

There are two versions of pins with slots that MLCad doesn't differentiate.

The thinner ones are the newest. I like them better, because bars (and therefore, soft axle ends) fit into them.

I don't know if they're weaker. Probably. But it's not like it's a rare part :)

[nerdsforprez]

I don't think these are the friction pins we saw 20 years ago, as those didn't have slots in the middle. Maybe something more recent. Here's a comparison of a 20 year old one with a new one, and one that I think comes from a Megablocks set:

You can tell by the tooth marks on the old friction pin that they are very hard to remove, like dr_spock said.

Yes, but as I mentioned in the post... there actually are two different kinds of the slotted version. By consensus... it sounds like it still reflects an earlier versus a later version, even in the slotted versions. As can be seen in the pics.... the pins I was playing with today were all slotted.... even though they had varying levels of thickness.

There are two versions of pins with slots that MLCad doesn't differentiate.

The thinner ones are the newest. I like them better, because bars (and therefore, soft axle ends) fit into them.

I don't know if they're weaker. Probably. But it's not like it's a rare part :)

Maybe not a rare part... but I would love a whole large lot of them. I know it probably does not make a lot of sense to BL stores to differentiate between the two, because they are so cheap. But I know personally I would gladly pay good money for the older, thicker version.

Even though you can place bars in the middle of the newer version, bars cost too. And if you were trying to make a large, strong build, placing bars in each pin would be tedious. I also prefer the newer version most of the time. But for large, big builds, or like truck trials with XL motors..... I would much rather prefer the older thicker versions.

[DrJB]

Then there are the pins that came 'permanently' mounted in some of the old technic rectangular frames. Permanent mean very difficult to take out. The one example I can think of is of that boat with 2 narrow hulls.

[RohanBeckett]

Yes to DrJB - it made the technic frames more 'kid proof'..

I got a 2nd hand one, but the pins were all bent and twisted.. I had to destroy them to remove them, but fortunately, didn't damage the frame, and I could rebuild the set, with regular pins.

I actually gave away all my ancient, original black pins, as I hated building (and pull apart) my vintage models with those ones..

I'm not that much of a purist that I care about them

[dr_spock]

I got a 2nd hand one, but the pins were all bent and twisted.. I had to destroy them to remove them, but fortunately, didn't damage the frame, and I could rebuild the set, with regular pins.

What did you use to get them out? Mine are still stuck.

[vliet]

I have that same frame in red and without excessive force it is impossible to remove the pins

[RohanBeckett]

What did you use to get them out? Mine are still stuck.

Brute force! <flexes Hulk Muscles>

oh... and helped by a decent pair of pliers..

twisted, and ripped it out... totally destroyed the pin.. but I didn't care.. ended up with another regular frame to use

[LennyRhys]

Haha I have a bag of those from set 8865 (Test Car, 1988) and I NEVER use them. Actually, I don't know why I haven't just binned them - they are pretty useless as Lego elements because they are so difficult to remove.

These friction pins were used in a number of Technic sets from the 1980s, but they were dropped because they had too much friction.

[Josephiah]

Having had a dark age spell spanning from the mid-90s (8880 and control centre II) to last year (42009), I had definitely noticed a difference in feel with the new pins, but hadn't subjected the change to such scientific scrutiny! Looks like they just increased the internal diameter a little to save plastic.

So yes, I'm pretty certain there are (at least) three versions:

1. The "no slot" version from the late 80s/early 90s - I well remember using my little teeth to extract them, and then my dad explaining that this would make them EVEN HARDER to remove!

2. 1st gen slotted version from circa 1994, or possibly even earlier - can't remember whether the compressor truck (92) or whirlwind rescue (91) had these or slotless.

3. 2nd gen slotted - wonder when these came in - around the time of the move to studless, perhaps? Or during TLG's cost-cutting years?

[nerdsforprez]

Haha I have a bag of those from set 8865 (Test Car, 1988) and I NEVER use them. Actually, I don't know why I haven't just binned them - they are pretty useless as Lego elements because they are so difficult to remove.

These friction pins were used in a number of Technic sets from the 1980s, but they were dropped because they had too much friction.

Would you be willing to sell? If so, send me a PM. Thanks! Sounds like everyone hates them.... understandably so... but I have use for them. If anyone is interesting in selling at a reasonable price (there is not really a market to my knowledge for them.... so no need to price gouge), feel free to send a PM my way.

[deraven]

OK, nerdsforprez, you're singlehandedly creating a market for these annoying pins! Now we have to see how much premium they can garner for the pain of sorting them out from the newer version...

Honestly, though, I have a portion of my collection sorted by vintage (nothing too OCD, but more like "I instantly know this set/part is from 20+ years ago, so I'll disassemble it into the Vintage bins") and, like you, I do also use those older friction pins in areas that I really do need the extra friction/strength (but where I also know I'll be relatively likely to get them out later if necessary).

[Kman860]

Those look like the "vintage" pins to me, don't have any old sets, but I have a couple bins I've bought from people and I've seen 1 or 2 of those pins, never noticed the difference until now...

[nerdsforprez]

I put this question out on the BL forum as well.... and I got this response.

"Incidentally, I just did a quick weight comparison and the thin-wall version

weighs 77% of the thick-wall version. That's a pretty big savings in materials."

I know this is an extrapolation.... but wondering if it is fair to say then, based on the above statement, that the older, thicker pins may be around 25% stronger. Perhaps even more given that relationships such as these are often exponential in nature.......but this would all have to be given to experimentation.

[bonox]

I know this is an extrapolation.... but wondering if it is fair to say then, based on the above statement, that the older, thicker pins may be around 25% stronger.

given the pins are pretty much only used in shear, and shear resistance is a direct function of cross section area, it would seem to me to be a reasonable assumption given no additional data.

under high load however, the pin deforming seems to be a significant mode of failure, meaning stiffness rather than strength is the limiting point of the pins. Given that, a performance greater than the proportional increase in mass also seems reasonable if you (edit: don't) have trouble stopping the connected parts coming out of plane, as typically happens in single shear designs.

You may find this interesting as well:

http://eprints.usq.e...esting_2012.pdf

often we design joints to fail in bearing before nett section failure or knife edge failure of fasteners - it would appear than lego bricks and liftarms have failure modes that are generally nett section failure of the structure element. You only get pin failure when you control the general structure deformation (by zip ties in his case or bars in the back of pins in others).

Edited September 28, 2015 by bonox

[Josephiah]

Would you be willing to sell? If so, send me a PM. Thanks! Sounds like everyone hates them.... understandably so... but I have use for them. If anyone is interesting in selling at a reasonable price (there is not really a market to my knowledge for them.... so no need to price gouge), feel free to send a PM my way.

The test car would almost certainly have had the older slotless impossible-to-remove pins, not the thicker slotted pins we've been discussing - just make sure you're talking about the same thing before you buy/sell!

[Rockbrick]

i dunno why but i still kept my old impossible to remove pins

as with age they get worse - but I tested them all and threw out the bad ones and kept the ones that still work or are even loose

[Blakbird]

What did you use to get them out? Mine are still stuck.

That part actually exists in a form which has the pins permanently attached.

[dr_spock]

That part actually exists in a form which has the pins permanently attached.

Thanks. That explains the difficulty in removing the pins. Why would they do that? It is confusing when it gets mixed in with other 6x4 frames.

[Blakbird]

Thanks. That explains the difficulty in removing the pins. Why would they do that? It is confusing when it gets mixed in with other 6x4 frames.

I don't really know why they would do that. I don't own any of the (few) sets that ever included it.