General Part Discussion

[R0Sch]

In case anyone else wants to use the new 3x3 Triangle Technic Panel in their digital builds, before it's officially added to Studio, here's the file:
https://limewire.com/d/ourm5#PQysgLfDtu

[M_longer]

The marvelous RC chassis was not that marvelous.

 

https://www.newelementary.com/2025/07/parts-review-august-2025-lego-technic.html 
 

[Bartybum]

What's the point of removing the battery if you can only recharge it via the hub? Is it in case the battery dies so that you can get a replacement?

[Aurorasaurus]

1 hour ago, Bartybum said:

Is it in case the battery dies so that you can get a replacement?

Yes, thats almost certainly the reason.

[Divitis]

Hello world,

Can anybody check if this ball (piece 52629)  is compatible with only this socket 39370  (which it is matched to in official sets, such as the drifting Nissan) or also either of these two?

1. 44358   https://www.bricklink.com/v2/catalog/catalogitem.page?P=44358&name=Cylinder Hemisphere 3 x 3 Ball Turret Socket with 2 x 2 Base&category=[Cylinder]

2. 92911   https://www.bricklink.com/v2/catalog/catalogitem.page?P=92911&name=Technic, Steering Ball Joint Large Receptacle&category=[Technic, Steering]

 

And how smooth is the rolling? I am thinking of using it for ball bearing.

 

Thanks!

Edited August 5 by Divitis
Images

[R0Sch]

2 hours ago, Divitis said:

Hello world,

Can anybody check if this ball (piece 52629)  is compatible with only this socket 39370  (which it is matched to in official sets, such as the drifting Nissan) or also either of these two?

1. 44358   https://www.bricklink.com/v2/catalog/catalogitem.page?P=44358&name=Cylinder Hemisphere 3 x 3 Ball Turret Socket with 2 x 2 Base&category=[Cylinder]

2. 92911   https://www.bricklink.com/v2/catalog/catalogitem.page?P=92911&name=Technic, Steering Ball Joint Large Receptacle&category=[Technic, Steering]

 

And how smooth is the rolling? I am thinking of using it for ball bearing.

 

Thanks!

If you'd have checked the part names and which sets they were used in, you'd quickly realize that these socket elements all use different ball diameters, hence not compatible to each other.
39370 only fits the 19mm (=2.4 studs) ball 52629
44358 only fits 3x3 hemisphere elements 44359
92911 only fits the 18mm (=2.2 studs) steel ball 99948 and the 92910 Ball Joint Pivot Frame

[Divitis]

7 minutes ago, R0Sch said:

If you'd have checked the part names and which sets they were used in

I did a cursory check and came out quite confused... probably could have been more thoroughly. Appreciate your support though. I owe you one 

[SNIPE]

This new part (7504) might be useful for air scoops:

 

I wonder if this part (5253) fits into a ball socket of some sort:

 

[Stereo]

5 hours ago, SNIPE said:

I wonder if this part (5253) fits into a ball socket of some sort:

 

If it's spherical (and not flattened out a bit, which it sort of looks like), then 24mm diameter makes it 3 studs, which might be the same as 44359.

[NathanR]

Hi all, I just got hold of 8851 Excavator, originally released in 1984 and featuring the original generation of pneumatic elements. Sadly, the set is missing its red pneumatic pump, part 4701c01.

I'm trying to find a replacement, but bricklink notes that the pump came in two versions - long stem and short stem - and does not differentiate between the two. There is further complication in that the pump also appears with spring and without. Will any red pump be good enough to work the model?  Which is the correct variant for 8851 - short stem or long stem? The box art suggests long stem, but photos online suggest a mix of long stem and short stem, so did the model get issued with both?

[Lipko]

11 minutes ago, NathanR said:

Hi all, I just got hold of 8851 Excavator, originally released in 1984 and featuring the original generation of pneumatic elements. Sadly, the set is missing its red pneumatic pump, part 4701c01.

I'm trying to find a replacement, but bricklink notes that the pump came in two versions - long stem and short stem - and does not differentiate between the two. There is further complication in that the pump also appears with spring and without. Will any red pump be good enough to work the model?  Which is the correct variant for 8851 - short stem or long stem? The box art suggests long stem, but photos online suggest a mix of long stem and short stem, so did the model get issued with both?

It's just the pump. I see no assembly reason why you couldn't use any type.

Edited September 4 by Lipko

[2GodBDGlory]

1 hour ago, NathanR said:

Hi all, I just got hold of 8851 Excavator, originally released in 1984 and featuring the original generation of pneumatic elements. Sadly, the set is missing its red pneumatic pump, part 4701c01.

I'm trying to find a replacement, but bricklink notes that the pump came in two versions - long stem and short stem - and does not differentiate between the two. There is further complication in that the pump also appears with spring and without. Will any red pump be good enough to work the model?  Which is the correct variant for 8851 - short stem or long stem? The box art suggests long stem, but photos online suggest a mix of long stem and short stem, so did the model get issued with both?

I do seem to remember that some of those old sets could come with different sizes of pumps.

The interesting thing with that old system is that the pumps and cylinders are actually functionally the same! I would think having a pump with the integrated spring would make operation easier, but if you don't mind manually pulling it up to pump again, one without would work, I think

[NathanR]

On 9/4/2025 at 1:22 PM, 2GodBDGlory said:

The interesting thing with that old system is that the pumps and cylinders are actually functionally the same! I would think having a pump with the integrated spring would make operation easier, but if you don't mind manually pulling it up to pump again, one without would work, I think

This is actually a pretty amazing feature of the original pneumatic system. I don't want to be pulling up the pumps manually though - I tried it with one of them and the cylinder's shaft immediately snapped off . This also brings a separate question of what (if any) lubricant can be safely applied to an old-style pneumatic cylinder?

Curiously, I have found photos of 8851 boxes suggesting that there were two editions of the set. The box art and photographs consistently show short-stem pumps on the model. However, the moulded plastic insert trays seem to have had a different sized compartment for the pump, according to whether a short-stem or a long-stem pump was included in the box.

[R0Sch]

Only 4 new parts have been added to PaB this month:


But you can now very conveniently see all the colors a part comes in. E.g. all beam type elements.
Note how a half beam costs just as much as a full beam even though it's half the amount of plastic or how a beam with alternating holes costs double than one with regular holes, even though it's the same amount of plastic. ;)

[R0Sch]

1 hour ago, NathanR said:

This is actually a pretty amazing feature of the original pneumatic system. I don't want to be pulling up the pumps manually though - I tried it with one of them and the cylinder's shaft immediately snapped off . This also brings a separate question of what (if any) lubricant can be safely applied to an old-style pneumatic cylinder?

Curiously, I have found photos of 8851 boxes suggesting that there were two editions of the set. The box art and photographs consistently show short-stem pumps on the model. However, the moulded plastic insert trays seem to have had a different sized compartment for the pump, according to whether a short-stem or a long-stem pump was included in the box.

I believe that the short stem pump is simply a design oversight or it was not a needed for some sets where linkages were used. The pump has to have the long stem because it contains the spring which when compressed takes up 18mm. So in order to have a full 3mm stroke of the cylinder the pump stem has to be just as long plus the length of the spring = 48mm. So the listings of pumps you see, where no spring is included is actually just the cylinder as you cannot remove it without cutting the plastic (see Link). So I think the long stem pump was used later on after the design was updated, the short was simply an initial cost saver because it contained the same parts as a cylinder plus a simple spring.

Edited September 7 by R0Sch

[ludov]

41 minutes ago, R0Sch said:

Only 4 new parts have been added to PaB this month:


 

How did that 5L connector end up under “beams”? 

[R0Sch]

1 minute ago, ludov said:

How did that 5L connector end up under “beams”? 

Beats me. LEGO logic... But the names are irrelevant anyway. The categories are and it's listed under Miscellaneous>Functional elements same as the cardan and cv joints. Strangely the universal joint is listed under Connectors>Connectors.

[Satisfied]

On 9/4/2025 at 8:22 PM, 2GodBDGlory said:

I do seem to remember that some of those old sets could come with different sizes of pumps.

The interesting thing with that old system is that the pumps and cylinders are actually functionally the same! I would think having a pump with the integrated spring would make operation easier, but if you don't mind manually pulling it up to pump again, one without would work, I think

Hello, will the technic book continue to update its content for 2025

[2GodBDGlory]

1 hour ago, Satisfied said:

Hello, will the technic book continue to update its content for 2025

Unfortunately, most likely not. I talked about it more in the topic for the book, but I'm no longer at the stage of life where I have the level of free time I used to, and I think updating the book is something that's going to be dropped.

[Satisfied]

31 minutes ago, 2GodBDGlory said:

Unfortunately, most likely not. I talked about it more in the topic for the book, but I'm no longer at the stage of life where I have the level of free time I used to, and I think updating the book is something that's going to be dropped.

Okay, we can only respect your choice and look forward to the opportunity to update in the future

[Ngoc Nguyen]

TLG has started including 3d printed parts in official sets. 

 

I wonder if there will be 3d printed parts in Technic in the future.

[MP LEGO Technic creations]

Possibly a few new technic elements in dark green.

#4 135° angled connector  and Liftarm bent 3x3 

 is included in (?) Pearl gold.

Edited September 9 by MP LEGO Technic creations

[Jockos]

1 hour ago, Ngoc Nguyen said:

TLG has started including 3d printed parts in official sets. 

I wonder if there will be 3d printed parts in Technic in the future.

I hope not. First of all, I don't and won't really like TLG putting 3D printed things in official sets. They drastically differ from the 'build it from small parts' mentality.

But, if the forced 3D printing is limited for accessories/decoration, that's fine. But if it means structural parts (beams, pins, axle) then that will be a disaster. I can't imagine a situation where a 3D printed part behaves better than a moulded one. 

If you have any ideas, please, let me know.

[2GodBDGlory]

6 hours ago, Ngoc Nguyen said:

TLG has started including 3d printed parts in official sets. 

I wonder if there will be 3d printed parts in Technic in the future.

Very interesting! I'm not sure how I feel about this specific instance, because it feels like it's a replacement for what could have been a traditional, multi-piece build, but I can see a place for it in low-production-number parts, like exclusive minifigure headgear that only needs to be in one set ever, where the higher per-part cost would still be cheaper than the big up-front cost of buying a mold.

The only other real reason to print a part would be to have properties that injection molding can't create, like the internal mechanisms in this train.

I don't really imagine we'll see much like this in Technic, since you have to remember that 3D printing is expensive at large scale, so it's really only going to be low-production specialty parts, and in Technic we don't have a ton of that.

The only Technic part from the last several years that I can think might have been good to 3D print is the Mack bulldog part, since it didn't need structural strength, and it only had to be used in one set.

Edited September 10 by 2GodBDGlory

[HorcikDesigns]

Do we have more information about the material and technology that was used for printing the small locomotive? It looks like SLS (sintered powder) which would allow for large quantity of pieces.