[HELP] Generic Building Help Topic

[Aurorasaurus]

3 hours ago, Milan said:

Technic Pub is for...anything but Lego :)

Oh, just one of english's many tricks, I thought it meant anything but still lego.. my bad :)

35 minutes ago, Carsten Svendsen said:

I should be able to drop it on the ground from standing height, and only have minimal cosmetic repairable damages.

Wow, thats very solid indeed.

5 minutes ago, 1gor said:

To make realistic model as much as possible with minimal parts as possible no matter propulsion, functions,  looks or construction (I usually use as much frames as possible).

How would you say the strength of your models is in a bit of rough play? Light weight = less forces under its own propulsion, arguably more sturdy than big strong builds sometimes.

[1gor]

31 minutes ago, Aurorasaurus said:

 

How would you say the strength of your models is in a bit of rough play? Light weight = less forces under its own propulsion, arguably more sturdy than big strong builds sometimes.

Something like that; currently I'm rebuilding onw my model and hope to finish it untill end of February and post some pictures of it. Basically I use frames 5 x 7, 5 x 11 H shape or 7 x 11 as much as I can. Propulsion is also very simple; mostly I use XL motors (Powerfunctions) and then upgear them (using spur gears because they are have less friction than bevel gears), then daytona or gray differentials (both tun smoother than red differntial introduced in 42109 set) and hub reduction at end... when trying to replicate shape I use mostly pannels because they are sturdier than bricks...

[pekka111]

Beginner question: all the beams have odd number of holes? Half beams have 6 hole version but not one with 4 round holes? So do you cut custom lengths if something else is needed?

Edited January 7 by pekka111

[allanp]

2 hours ago, pekka111 said:

Beginner question: all the beams have odd number of holes? Half beams have 6 hole version but not one with 4 round holes? So do you cut custom lengths if something else is needed?

If you want to, it's your Lego. Your question is essentially a question of Lego purism. Some members like to stick strictly to what comes in a Lego box unmodified. Others allow themselves to go crazy with modified parts, 3D printed parts, third party parts (such as buwizz or aluminium beams and steel axles), clone brand parts, brushless motors, metal bearings and so on. But when posting your model in the forum it's usually customary (though not required) to state what parts stray from pure, unmodified Lego. Enjoy the hobby how you please, there's no judgement here. And besides, don't Lego designers themselves create new parts for themselves to use?

[gyenesvi]

3 hours ago, pekka111 said:

Beginner question: all the beams have odd number of holes? Half beams have 6 hole version but not one with 4 round holes? So do you cut custom lengths if something else is needed?

I guess most people just try to work around that problem with some other parts that are available, but resulting in more bulky builds. Do as you find suitable, but also make sure to complain about it in public forums, so that TLG realizes that we all need some beams of even lengths, such as 4 and 6 :) The more of us spell that out, the more chance that we'll see those appear in the future!

[pekka111]

Thanks :) I guess 3D printing is difficult, since you would like the tolerances to be quite small. Is there a reliable (Chinese) brand that makes original looking and durable parts in those missing sizes?

Edited January 7 by pekka111

[Aurorasaurus]

2 minutes ago, pekka111 said:

Thanks :) I guess 3D printing is difficult, since you would like the tolerances to be quite small.

5mm for pin holes, 6.2mm for the little counterbore or whatever it is, 1mm depth for that too. 8mm spacing between holes. Theres even a site for it: https://marian42.de/partdesigner/

That said, you should make a simple test piece to dial it in even more for your machine.

[pekka111]

3 minutes ago, Aurorasaurus said:

5mm for pin holes, 6.2mm for the little counterbore or whatever it is, 1mm depth for that too. 8mm spacing between holes. Theres even a site for it: https://marian42.de/partdesigner/

That said, you should make a simple test piece to dial it in even more for your machine.

Thanks! We have cheap printing here in public libraries so maybe I'll do a test.

[Aurorasaurus]

5 minutes ago, pekka111 said:

Thanks! We have cheap printing here in public libraries so maybe I'll do a test.

https://bricksafe.com/files/Aurorasaurus/miscellaneous/3d-print-tolerance-tester/tolerance tester.stl
Here's a simple test piece I use for checking how different filaments tolerances are, this should be perfect for you. 0,9, 1, and 1,1 on the side are how deep the counterbore is. And the other numbers are the diameter of the pin hole.

[1gor]

13 hours ago, pekka111 said:

Beginner question: all the beams have odd number of holes? Half beams have 6 hole version but not one with 4 round holes? So do you cut custom lengths if something else is needed?

Personally I don't cut anything (that is why I have lots of trial and error). Lots of time I needeed 8 studs long liftarm...but I can only hope for it. Generally I use only Lego parts, but I'm very limited with Lego tire dimensions...

BTW, there is also very usefull 9 studs long liftarm ½ stud thin...

Edited January 7 by 1gor

[2GodBDGlory]

9 hours ago, pekka111 said:

So do you cut custom lengths if something else is needed?

Generally no. Some people go all-out with modification, and many will use specialist third-party parts if they fill a gap Lego can't really fill, and others use only official Lego. It's uncommon to use modified parts for basic structure. You're free to do as you wish, though!

[Stereo]

Odd numbers make more sense on their own - you can combine them to get even numbers, but you can't combine even beams to get an odd length.  Inconvenient if you need the span to be a single beam, but usually Technic sets just design for those sizes to be odd numbers I guess.

[gyenesvi]

8 hours ago, pekka111 said:

Is there a reliable (Chinese) brand that makes original looking and durable parts in those missing sizes?

Weirdly enough, no, Chinese brands don't really get creative and produce all the missing sizes, they mainly copy the existing parts. Though Cada makes some unique parts, but those are rather new designs than missing sizes in an existing concept. I find that quite weird an sad (would be a low hanging fruit for them).

7 hours ago, 1gor said:

BTW, there is also very usefull 9 studs long liftarm ½ stud thin...

Which part is that? I have never seen a thin liftarm longer than 7L.

1 minute ago, Stereo said:

Odd numbers make more sense on their own - you can combine them to get even numbers, but you can't combine even beams to get an odd length.  Inconvenient if you need the span to be a single beam, but usually Technic sets just design for those sizes to be odd numbers I guess.

I don't buy that logic :) Odd numbers simply come from the fact that original Technic bricks have even studs (for even width builds), and they had odd number of holes shifted half a stud relative to the studs, such that there's a hole that falls to the middle, and also so that other bricks connected perpendicularly with pins would have enough clearance. Later the studs where shaved off, the ends were rounded off, and there was the birth of the studless liftarm, made around the pinholes themselves, and hence technic models became odd width because of that. But for the other two dimensions (length, height), there is no natural center, so even liftarms would also make perfect sense there, and would be just as useful.