[HELP] Generic Building Help Topic

[heyitsdisty]

Hey folks, anyone know if it's possible to run higher-voltage batteries in a WeDo 2.0 hub like you can with other hubs?

I would give it a try but I don't want to fry the hub if it doesn't work!

 

 

[brettbarbaro]

Hi! 
This is my first post on Eurobricks. I am an AFOL with a four year old son. We are focused on technics. We are starting to get deeper into it. Is there a book that I could read to give me some general knowledge?

For some background, I’ve been doing Lego for almost 50 years, but Just started dabbling in technics about 10 years ago. Focused almost entirely on MOCs. We made the tank 42140 and then took it apart for pieces. I’ve made about 10 orders on bricklink, just to have some basic material. Lots of motors (power functions, not powered up) and wheels - my son is really into cars. We just built the Arocs MB truck (used). I often find myself thinking about the principles of technics model design, and am wondering if there are any general guides on the subject.

Edited February 23, 2023 by brettbarbaro

[2GodBDGlory]

Just now, brettbarbaro said:

Hi! 
this is my first post on your brakes. I am a technics a FOL with a four year old son. We are starting to get deeper into it. Is there a book that I could read to give me some general knowledge?

If you're looking to get into MOCing, there's probably no better resource than The Unofficial Lego Technic Builder's Guide. If you just want to drool over awesome MOC's, Incredible Lego Technic (by the same author) is also pretty awesome! If you want to study the history of Technic sets, there aren't any published books I know of that cover it, but you could try the website Blakbird's Technicopedia, or download/print the exhaustive history of Technic sets I wrote, through this thread here:

Anyways, welcome to Eurobricks!

[brettbarbaro]

Perfect! 😊👍 I will start reading immediately! Thanks for your help.

[Jundis]

Hi guys! Currently I am planning a 4WD motorized John Deere 8R with different tire sizes (front 81x35, rear 107x44). As I dont't want to use a mid diff, the speed difference is an issue, as I can't achieve a perfect gearing without many gear steps and thus friction. Right now, the speed difference is less than 2% between front and rear axle.

Has anybody already experience in how much "overdrive" and therefore slip is acceptable so that the machine doesn't wobble while driving?

[Kostq]

Maybe wrong topic, but:

how the heck do you take out one of these after it's in? Besides pushing it from the rear.
It allows for locking parts together like it's cousin   but it is a one-way lockage and can lead to non-reversible assemblies.
Any tips on which pieces do fit inside and are able to take it out?

Edited March 13, 2023 by GTS

[Jurss]

[2GodBDGlory]

5 hours ago, GTS said:

Maybe wrong topic, but:

how the heck do you take out one of these after it's in? Besides pushing it from the rear.
It allows for locking parts together like it's cousin   but it is a one-way lockage and can lead to non-reversible assemblies.
Any tips on which pieces do fit inside and are able to take it out?

Bars will fit into both ends and go in one stud, so you might be able to get enough friction to pull it out that way.

[Jundis]

5 hours ago, GTS said:

how the heck do you take out one of these after it's in?

looks at you in a surprised way...

[NathanR]

Hi everyone, I'm trying to build a large scale model of the ATLAS detector at Cern, using regular system bricks suspended from a technic skeleton.

The model is basically an octagonal barrel. I use 44224/44225 click hinges to form the corners, and two 7L beams to get a side length of 17 modules (or 18 studs) to get an octagon diameter that is close enough to be in system (41.04 studs diameter). I have a technic axle running the length of the model through the holes in the click hinges. I also use two of 32557 to hold the frame in place above the blue base block:

There will be five such octagonal frames, but ultimately all the weight of the model (estimate about 7-8kg) will be going through the two 77765 3L pin with stop at the base of each frame. I don't think the pins can carry this weight, and I don't see how to add technic bricks for support because the beam is an even-number length. Is there any way to make this connection stronger? 

[Jurss]

Only suggestion - multiply connection points.

I'm just curious - where there will be 7kg+?

[NathanR]

18 minutes ago, Jurss said:

Only suggestion - multiply connection points.

I'm just curious - where there will be 7kg+?

You're right, of course, but I just don't see how to add additional connections points... It's awkward because I have transition from odd-based studless technic to even-based Lego system.

The 7kg comes from what's on top. This is a prototype render, with only three of the octagon frames - the central ones are are C-shaped brackets, the outer two are full O-shaped rings. An inner octagon rings, built using the new 79846 bent plate will provide some extra support, but ultimately all the weight goes down to the technic beams on the bottom of the barrel.  More blue blocks (muon chambers) will be suspended from the 3x3 cylinders running the length of the model (the toroid magnet coils). Then there will be an entire separate cylinder unit inserted in the centre, housing the calorimeters and inner detector:

[Jurss]

OK :)

If not mistaken, there will be some 10 connection points, so some 800g on each. Not very critical, but could be close to limits (lego plastic is pretty sturdy), especially, if they need to hold also some moving of whole structure to some exposition or something.

I'm afraid, that those lower click hinges could be weakest point, or that section of some 4 studs from that vertical beam to that click hinge.

[pleegwat]

Would it be possible to use 1x2 jumper plates to bridge the half-stud offset?

[mdemerchant]

Your large render seems to have different support than your first image.  It now looks like you are using 2x 3L pin with bush for each connection point, is that right?  Anyway, in terms of strength that should be pretty much exactly the same as the first arrangement with 1x 3L pin with stop in double shear.

Pins are pretty sturdy, I bet they will be fine.  But it's quite easy to just hang a weight off them and do a quick test to put any concerns to rest.  I would be more worried about the octagon shape getting distorted from the weight but I have no experience with the click hinges.  I guess you have a lot of them but am I correct in thinking they are the only thing holding the octagon in shape?

[NathanR]

Thanks for all the advice, it's reassuring to know that pins aren't that fragile. 

6 hours ago, pleegwat said:

Would it be possible to use 1x2 jumper plates to bridge the half-stud offset?

I considered that, but then I would need an odd-sized technic brick to fill the gap. And there just aren't enough pin holes available to hold the beams together and slot them into a brick.

21 minutes ago, mdemerchant said:

Your large render seems to have different support than your first image.  It now looks like you are using 2x 3L pin with bush for each connection point, is that right?

Oh dear, I grabbed an older render, I was just trying to show the overall structure that frame has to support. I have five octagonal frames, a 4L wide one that uses the 3L pin with bush, and four other frames that sue the 3L pin with stop.

My new solution is to add in a few 1x2 bricks with 2 holes, and 1x2 plates with pin hole. This feels a bit wrong, somehow, like there should be a more elegant way to do it, but it uses every available pin hole:

25 minutes ago, mdemerchant said:

I would be more worried about the octagon shape getting distorted from the weight but I have no experience with the click hinges.  I guess you have a lot of them but am I correct in thinking they are the only thing holding the octagon in shape?

You make a good point, the click hinges are the main thing holding the shape, and I will have a total of six hinges distributed along the length of the barrel. However, I have more planned.

The reason I use a pair of 7L beams for each side of the octagon, instead of a single 15L beam, is that the diameter of the ring is 41.04 studs. That's close enough to be in system. You may have spotted some radial beams on the render, these are connected to an axle passing through the hole in the click hinges. The axle should bisect the octagon corner, at 67.5 degrees, but if I move them to 67.4 degrees then the radial beam forms the hypotenuse of a 5-12-13 Pythagorean triple. I use half this due to lack of space, so it's really a 2.5-6-6.5 triangle. 

At 6.5 studs from the pin hole in the click hinges, I can link a pair of the radial beams with a 13L beam. 13L is another magic number, as an octagon with side length 12 modules (or 13 pin holes) will be 28.97 studs across. So by mirroring the base section at the top of the barrel, I will get (Pythagorean triple + octagon + Pythagorean triple) = (6 + 28.97 + 6) = 40.97, almost perfectly matching the outer octagon.

The smaller octagon doesn't need to use click hinges, I can use part 79846 which conveniently has a pin hole at the corner, reinforce it with plates and brackets so it cannot be compressed, and that should be strong enough to lock the outer ring in place, and transmit all the weight directly down into the base block.

 

[Jurss]

It seems, that You have had lot of thinking. That's good.

And still, I see, that it is planned, that those click hinges also will be supported, there where will be construction, on which they will rest, so those two pins then really doesn't seems an issue.

Anyway, first buy parts (if You don't have) for one ring to test everything. Of course, if money is not an issue, then this step is not necessary :)

[NathanR]

Hi all, it's me again, still working on the Atlas model. I'm trying to create a thin, C-shaped bracket - basically an octagon with a few sides removed - but the top of the bracket needs to be rigid as it will carries some weight. 

Can something like this work? 

It seems valid in Stud.io, but is it actually "in system"? Do the click hinges have a pivot point that matches the centre of a technic pin hole? 

 

[Carsten Svendsen]

11 hours ago, NathanR said:

Hi all, it's me again, still working on the Atlas model. I'm trying to create a thin, C-shaped bracket - basically an octagon with a few sides removed - but the top of the bracket needs to be rigid as it will carries some weight. 

Can something like this work? 

Spoiler

It seems valid in Stud.io, but is it actually "in system"? Do the click hinges have a pivot point that matches the centre of a technic pin hole? 

 

Can confirm, works flawlessly and is 100% in "click"

Unfortunately, liftarms have a different bend angle than the #4 connector, so they won't work. This will be rigid but only to a certain weight limit, as the 2L pins will start to give out.

Edited April 26, 2023 by Carsten Svendsen

[Jurss]

7 hours ago, Carsten Svendsen said:

Can confirm, works flawlessly and is 100% in "click"

Yes, but it doesn't add to rigiditty. As I understood, @NathanR wants some connection also in the middle, to have reinforced structure.

If these would be used

and and, of course, cross axle used to connect them, then some rigidity could be added without connecting middle hole.

[vascolp]

Try this. Very rigid, very strong.

Maybe not so nice seen from the outside...

[vascolp]

You can replace this  with this  to make it look better, but with less studs.

 

[Dr_Chronos]

I know there are many lego-compatible 3rd party motors with many spec comparisons, but i almost never see the sound level which is what I want to know most. What are some options for motors if noise is my biggest concern?

[Technic tango]

On 5/3/2023 at 11:24 AM, Dr_Chronos said:

I know there are many lego-compatible 3rd party motors with many spec comparisons, but i almost never see the sound level which is what I want to know most. What are some options for motors if noise is my biggest concern?

Possibly micromotor from cada?

 

_____________________________

different post due to merging

 

 

Im making a bogey with self contained suspension and steering, but due to lego axle torsion there is alot of play. I attempted to add sort of a steering lock here with the pneumatics but that would make the suspension not work and it would introduce bump steer. Any thoughts on how to add a lock here?  Bricksafe image

Edited May 16, 2023 by Technic tango
It auto merged me

[Zerobricks]

On 5/3/2023 at 8:24 PM, Dr_Chronos said:

I know there are many lego-compatible 3rd party motors with many spec comparisons, but i almost never see the sound level which is what I want to know most. What are some options for motors if noise is my biggest concern?

From my experience, the PF and PU XL motors are the quite quiet thanks to the low internal friction and low output speed. Also the old 9V block motor, 43362 was very quiet too: