When did LEGO start printing the part numbers on the pieces?

malachirobertson

I have been searching for this answer on the internet and haven't come up with anything definitive.  Anyone know?
Thanks.

Pitfall69

paging @Istokg !!!

Baby_Yoda

Would it have been around the time Technic panels were introduced? If I recall, they needed to put the numbers on those because it was otherwise difficult to distinguish between left and right pieces - they had a smooth surface rather than studs, so there was no reference point. I'm no expert, though. Just throwing out ideas until one comes along...

LusiferSam

Some time in the 80s.  Not sure if it was the early, mid or late 80s.  They add part IDs before they start adding ©LEGO on the undersides.  ©LEGO started in the early 90s.  Before part IDs era there was the void era.  After the obscured Pat Pend bricks ended most bricks only had a mold number.  Hence they were void of most markings.  This is also when a number of PIPs started to be moved.

Astrobricks

Technically, the part numbers are not printed on the pieces, they’re molded right in.

graphite

Baby_Yoda said:

Would it have been around the time Technic panels were introduced? If I recall, they needed to put the numbers on those because it was otherwise difficult to distinguish between left and right pieces - they had a smooth surface rather than studs, so there was no reference point. I'm no expert, though. Just throwing out ideas until one comes along...

What you are referring to is the panel number which is different.  The technic panels have those numbers to identify the correct size and side, but they should also have the mold number which is what the OP is asking about.

For example this part
https://www.bricklink.com/v2/catalog/catalogitem.page?P=64391
Would have a #4 in a circle on it indicating which panel type it is, but would also have 64391 on the part in very small print.

Baby_Yoda

Ahh, that makes sense. I must have gotten the two confused. 

CCC

And just as confusing is that some modern parts being produced today do not have part numbers or the LEGO logo. Which can be problematic if you sell them then the buyer claims they are fake.

Astrobricks

CCC said:

And just as confusing is that some modern parts being produced today do not have part numbers or the LEGO logo. Which can be problematic if you sell them then the buyer claims they are fake.

At least you can show them BrickLink (if you can find the part without a number).

CCC

Although that doesn't always work ...

https://www.bricklink.com/message.asp?ID=1133764

stlux

CCC said:

Although that doesn't always work ...

https://www.bricklink.com/message.asp?ID=1133764

Wow, what a horrible buyer. Fortunately it seems BL removed the negative feedback.