GBC General Discussion

[RohanBeckett]

ahh.. another on my to-build list! such a simple/interesting mechanism.. should be easy enough to copy from the video! :)

by the looks of it, I can't see why this wouldn't work on a slight incline up?

 

[doug72]

9 hours ago, RohanBeckett said:

ahh.. another on my to-build list! such a simple/interesting mechanism.. should be easy enough to copy from the video! :)

by the looks of it, I can't see why this wouldn't work on a slight incline up?

 

Have studied the video many times, sorted out parts required & now building this to suit my requirements.
Once built will test to see the maximum angle it will function at.

[DaFokka]

What is the minimum angle for a slope so that balls will never stop on it?

Edited February 21, 2017 by DaFokka
grammar

[ALittleSlow]

3 minutes ago, DaFokka said:

What is the minimum angle for a slope so that balls will never stop on it?

Balls are evil. 90 degrees. 

My rule of thumb in to go no less than one plate drop per six studs. One plate per four studs is probably the number you're looking for, though. Most balls have a small pit. Rest a ball on this pit on a level surface. Now tip the surface until the ball starts rolling. The angle of the surface when the ball starts rolling is your minimum.

 

[DaFokka]

8 minutes ago, ALittleSlow said:

Balls are evil. 90 degrees. 

My rule of thumb in to go no less than one plate drop per six studs. One plate per four studs is probably the number you're looking for, though. Most balls have a small pit. Rest a ball on this pit on a level surface. Now tip the surface until the ball starts rolling. The angle of the surface when the ball starts rolling is your minimum.

 

Thanks! I am working on a module with a 1 plate drop per 16 studs, which would seem to be enough. Single balls never manage to stay put with this angle. However, if there are multiple balls in single file become stationary, the angle alone is not enough to get them moving again. I am currently testing with 14mm beads which have fairly small holes so I'm hoping the Quercetti marbles I've just received will perform better.

[doug72]

48 minutes ago, DaFokka said:

Thanks! I am working on a module with a 1 plate drop per 16 studs,

For a slope of 1 in 16 you need to support the balls by their sides (i.e. at 5 & 7 o'clock) so that the hole in the ball does not run on a surface.
I use 16L straight Lego rail track to achieve this, studded beams with smooth plates over the studs or studded beams turned upside down.
Lego roofing bricks also make good ball runs.

[DaFokka]

4 minutes ago, Doug72 said:

For a slope of 1 in 16 you need to support the balls by their sides (i.e. at 5 & 7 o'clock) so that the hole in the ball does not run on a surface.
I use 16L straight Lego rail track to achieve this, studded beams with smooth plates over the studs or studded beams turned upside down.
Lego roofing bricks also make good ball runs.

Oops, I actually meant 1 brick per 16 studs, so that is 3 plates per 16 studs. I use the sloped tiles too, they look really nice.

[doug72]

19 hours ago, RohanBeckett said:

by the looks of it, I can't see why this wouldn't work on a slight incline up?

 

Now built the ball transfer section and it doesn't like any sort of incline, highest it worked at was a slope of 1:32. Any higher balls don't transfer and jam.
There is alot of backlash in the gears. Have had to set it up so the M motor runs in one direction only. Took awhile to figure out the ball holders as I had used the wrong part causing balls to stick in the holders. hard to see from the video as most ball holder parts are black.
Used a cross block 90 deg - 1 x 2 axle / pin instead of a 1 x 2 axle / pin or 2 x 0.5 with axle holes.

[doug72]

Now built the Nxtstep101  GBC Mechanical Chain module using the original design for ball transfer arms driven by 10 x 16T gears.

Found that excessive gear backlash caused problems with the timing and settings for the ball arms and can only run OK with M motor running in one direction. With motor reversed balls failed to transfer properly.

 

Original drive system:-

IMG_4357 by Doug Ridgway, on Flickr

 

Set out to improve the drive system and eliminate the 16T gears, modified drive system uses 12T bevel gears.
Result runs much smoother with no gearing backlash.

M motor with 8:1 reduction for slighly faster running than original design with 9:1 reduction and more compact.

The image shows how.
 

IMG_4359 by Doug Ridgway, on Flickr

 

Next step is to build the ball loading and unloading mechanisms.

Edited February 22, 2017 by Doug72

[doug72]

On 2/22/2017 at 2:02 PM, Doug72 said:

Next step is to build the ball loading and unloading mechanisms.

Further modifications made.

 

Gearing:
Now uses only 12T double bevel gears.

 

Ball loading:

Uses the same arrangement as I developed for my Bucket Wheel GBC lift and is operated by trip levers.

 

Unloading balls:

As the original design of this GBC module discharges balls at a low level it was not possible to connect up to a return runway or to another GBC module.

 

Therefore have made the last ball transfer arm longer and it is now able to lift balls up to the return runway at 11L height ( possible longer arms would also work).

M motor drives the last arm then the other 3 short arms via the eight 12T double bevel gears.

 

I had trouble with some balls getting stuck in the transfer arms so changed the pin/ball pins to blue pin/axle and now works well.

 

IMG_4369 by Doug Ridgway, on Flickr

 

 

IMG_4372 by Doug Ridgway, on Flickr

 

Video:

 

Edited February 24, 2017 by Doug72
video link.

[Maico]

The GBC circuit at LEGO World Copenhagen:

 

 

[Captainowie]

Nice. I do like to see independent modules with a common driveshaft! I also particularly liked the Friends slide Archimedes screw, that was pretty neat. Pity about the spill rate on that one though.

 

Owen.

[Maico]

At around 7:00 until 8:30 the two towers are driven by 8 XL motors on top of each individual stack.

At around 4:00 until 5:00 one XL motor is driving 10 of these modules. The last one is driven by one M motor.

At around 13:40 until 14:00 there are 3 conveyors being driven by one L motor.

[9v system]

@Maico I posted an instruction request on the Facebook page for the black module with the steps that move up at the same time.

[Maico]

can you give me a pointer which black module you are refering to? If it is mine, I can...

[9v system]

11 minutes ago, Maico said:

can you give me a pointer which black module you are refering to? If it is mine, I can...

There's a photo on the Facebook group which I posted.

[TTR]

On 26/2/2017 at 9:12 AM, 9v system said:

Der er et foto på den Facebook-gruppe, som jeg udstationeret.

Facebook link?

[9v system]

@Courbet could you do more of superfin619s modules? i would like to help

[schraubedrin]

Another GBC video on the official LEGO Technic facebook page:

The future seems bright

[Maico]

hmm, he looks familiar to me...

 

[dr_spock]

GBC display at Brickfete 2017

 

 

[rollermonkey]

Anybody see that there will be solid black balls in one of the Fall Star Wars sets? 

(I think that's a new color, right?)

[RohanBeckett]

as much as I'd love to have another source of GBC balls.. I have a hunch that these will be rubber ones

[Lasse D]

Good catch. However. The molding indentation seems rather large and might make these balls become stuck more easily. Has anyone tried them out?

[Captainowie]

Zamor spheres and the balls that come with Mindstorms have that large indentation. You _can_ make a GBC out of them, but it's trickier.