Discord post: discord.com/channels/649165975647682560/649172304823058443/803237367254614036
Rossero Bertolli
A "latchless" gate system that ensures a constant height for the top marble
Discord post: discord.com/channels/649165975647682560/649172304823058443/803237367254614036
Discord post: discord.com/channels/649165975647682560/649172304823058443/803237367254614036
updated 3 years ago
Discord post: discord.com/channels/649165975647682560/649172304823058443/803237367254614036
Adjustable height modules: youtu.be/uO_yaiUzQH4
Constant radius pocket divider: youtu.be/wOkb1nRqHEg
The hype is on for the next Wintergatan video!
And thanks Martin for trying out my prototypes
By placing an actuated divide by 4 directly against the fishstair, the system can work a lot more reliable with less edge cases. The fishstair actuates the unloading of the divide by 4, independent of the amount of marbles that are loaded. But the divide by 4 can never load (and thus unload) more than four marbles at a time.
Because the exit is open and there is only one row of marbles moving to the fish stair at a time, there is no risk of climbing or pinching.
There is only one problem with this current prototype and that is that the 'exit lanes' are unconstrained, even in the loading position. With high marble pressure this can result in a bunching up of marbles. This can easily be resolved by having a top bar/system that prevents the marbles from exiting while loading. When the system tips over, the marbles can pass underneath the bar. This system is integrated in my other divide by 4 prototypes:
youtu.be/m2y2POjcXas?t=8
The cogs and lever can be lasercut metal while the marble path can still be a combination of plywood and metal rods.
Advantages:
- Less pressure sensitive (pressure makes the thing work)
- Continuous motion
- Motion integration between dropper and gate
- Looks cool (subjective)
Discord post:
discord.com/channels/649165975647682560/649172304823058443/814633925703761920
Inspiration by:
Fillos
discord.com/channels/649165975647682560/649172304823058443/776223831382556682
Gonzonator1982
discord.com/channels/649165975647682560/649172304823058443/814514028340183081
Timestamps:
0:00 - introduction
0:22 - Analysis
1:13 - Martin's solution (angles)
1:40 - Stiffer design solution
2:02 - Window slots vs. Friction explanation
2:44 - Low wear/friction inserts
3:15 - Questionmark design (Best solution imho)
5:04 - Roadmap to success
6:08 - Pressure resistant marble gates
6:33 - Final remarks
Links:
Stiffer design
discord.com/channels/649165975647682560/649172304638640130/812456198867386428
(overrotation) friction explanation:
discord.com/channels/649165975647682560/805996476991406101/808300469654913054
Inserts example:
discord.com/channels/649165975647682560/649172304823058443/813010438273892362
Questionmark design:
discord.com/channels/649165975647682560/649172304823058443/812648693390901268
youtu.be/ru_dVQ-guW8
It is less exciting than the rolling marble counter weight, but from a mechanical standpoint: static is better.
This is my proposal for an improved divide-by-4 system that reliably only tops over at four marbles and only tips back when completely empty. The placement of the weight is critical: not only is the horizontal arm important for topping over, but the vertical placement determines the reduction in moment arm when in unloading position, needing just one marble to stay down.
This is where Martins current divider comes short: The counterweight is a compromise, it may tip over at 3 marbles and tip back before fully unloaded. Another problem martin faced whas that the que wasn't held back in the unloading position. With better path constrainment this is solved as well.
Advantages as I see it:
Marble
- Aesthetically more pleasing
- More stable tipping action
- Faster
Static
- "Easy" adjustment
- Less physics involved during design
- Keep It Stupid Simple
Prototyped on a Dutchy 3D printer
www.dutchy3d.nl
My conjecture was that the 25 degree track would be more suitable for a steeper marble divider arrangement (incline).
As can be seen in the tests, the 20 degree version works reliably between a 3 to 5 degree incline whereas the 25 degree version works reliably between 4 and 6 degrees.
The conclusion is that by rotating the designed track along it's axis, it can be tuned to the desired incline to perform optimal.
I could win my very first 3D printer, a vote would be very appreciated :D
This nutcracker is printed using Innofil3D's recycled PET on a Felix 2.0 printer. The nutcracker can crack walnuts with ease and makes use of the flexibility as well as the strength of the filament. The product is subjected to flex, tension and pressure at the same time.
Music: Louane - Maman (LoΓ―c Coppola Remix)
Don't try this in your backyard!
The fireball is very, very hot. The candle-grease will keep burning when it falls on the ground, on water and even when it leaks on you. So be careful!
Mini DV d001, worlds smallest voice recorder
(cheap MD80 replica)
Bought it for 13,99 on deal extreme
Mounted the camera with the supplied bracket on the front fork of my mountainbike to go shopping.
Things you should know:
- Micro SD card not supplied! will cost as much as the camera itself
- Date cannot be turned off, I cropped it away
- Video is too wide, had to change the aspect ratio
- Manual is readable, not that bad. camera works without driver
- To find other video's made with this camera search for mini DV d001
- Really cool gadget!
Things I did using Virtual Dub
- Cropped the video 20px on top and 30px on the bottom to lose the date
- Stretched the video back to 480 to have the right aspect ratio
(I divided the video in two for youtube in movie maker, that created the black bars at the top and bottom)
Mini DV d001, worlds smallest voice recorder
(cheap MD80 replica)
Bought it for 13,99 on deal extreme
Mounted the camera with the supplied bracket on the front fork of my mountainbike to go shopping.
Things you should know:
- Micro SD card not supplied! will cost as much as the camera itself
- Date cannot be turned off, I cropped it away
- Video is too wide, had to change the aspect ratio
- Manual is readable, not that bad. camera works without driver
- To find other video's made with this camera search for mini DV d001
- Really cool gadget!
Things I did using Virtual Dub
- Cropped the video 20px on top and 30px on the bottom to lose the date
- Stretched the video back to 480 to have the right aspect ratio
(I divided the video in two for youtube in movie maker, that created the black bars at the top and bottom)
part one: http://www.youtube.com/watch?v=5GZb2FmHlbE (empty bottle)
I did this experiment on my balcony, but I'v taken a lot of safety measures.
DO NOT TRY THIS YOURSELF!
it is seriously dangerous!
It's a normal sized firecracker in a water filled 33cl grolsch beer bottle.
Here are the calculations for the pressure in the bottle for a closed bottle
(assuming the reaction has taken place before the water can leave the bottle)
I'm assuming the firecracker contains aluminium-perchorate flash powder.
The reaction taking place is as following: 3 KClO4 + 8 Al β 4 Al2O3 + 3 KCl
I've measured that the firecracker contains 3 grams of flash powder.
The molecular mass of perchlorate is:
39,10+12,01+126,9+4*16,00 = 242,01 g/mol
The molecular mass of aluminium is:
26,98 g/mol
The molecular mass of 3 KClO4 + 8 Al is:
3*242,01+8*26,98 = 941,87 g/mol
The total amount of 3 KClO4 + 8 Al will be:
n = m/M
3,0/941,87 = 3,2E-3 mol 3 KClO4 + 8 Al
n*3 = 9,6E-3 mol perchlorate
n*8 = 25,6E-3 mol aluminium
9,6E-3+25,6E-3 = 35,2E-3 mol flash powder
Calculating the total amount of gas (n/11*8)
35,2E-3/11*8 = 25,6E-3 mol gas
The pressure inside the bottle:
Assuming the water can't be compressed the gas can only be compressed in the small pocket created by the firecracker itself. The volume of the firecracker is:
6,2Ο0,6^2 = 7,01cm^3
The pressure inside this volume will be:
p = n*R*T/V
p = 25,6E-3*8,3145*293/7,01E-6 = 89,0E5 Pa
Pa is in N/m^2. The water will transmit the force from a small surface (outside of firecracker) to a large surface (inside of beer bottle).
The outside surface of the firecracker is 25.6cm^2
The inside surface of the beer bottle is 296,9cm^2 (did my math)
The pressure on the bottle will be:
89,0E5/296,9*25,6 = 7,67E5 Pa
This is allmost 8 bar, the bottles have to withstand (at least) 5 bar
This is why the bottle explodes in pieces.
Watch my previous video for the same experiment, but this time with an empty bottle! Will it break too?
previous video:
http://www.youtube.com/watch?v=5GZb2FmHlbE
Part two: http://www.youtube.com/watch?v=gHItDCnCLs8 (water filled bottle)
I did this experiment on my balcony, but I'v taken a lot of safety measures.
DO NOT TRY THIS YOURSELF!
it is seriously dangerous!
It's a normal sized firecracker in an empty 33cl grolsch beer bottle.
Here are the calculations for the pressure in the bottle for a closed bottle
(assuming the reaction has taken place before the air can leave the bottle)
I'm assuming the firecracker contains aluminium-perchorate flash powder.
The reaction taking place is as following: 3 KClO4 + 8 Al β 4 Al2O3 + 3 KCl
I've measured that the firecracker contains 3 grams of flash powder.
The molecular mass of perchlorate is:
39,10+12,01+126,9+4*16,00 = 242,01 g/mol
The molecular mass of aluminium is:
26,98 g/mol
The molecular mass of 3 KClO4 + 8 Al is:
3*242,01+8*26,98 = 941,87 g/mol
The total amount of 3 KClO4 + 8 Al will be:
n = m/M
3,0/941,87 = 3,2E-3 mol 3 KClO4 + 8 Al
n*3 = 9,6E-3 mol perchlorate
n*8 = 25,6E-3 mol aluminium
9,6E-3+25,6E-3 = 35,2E-3 mol flash powder
Calculating the total amount of gas (n/11*8)
35,2E-3/11*8 = 25,6E-3 mol gas
The pressure inside the bottle:
We first have to calculate the total amount of air before the reaction:
n = p*V/(R*T)
n = 1,013E5*330E-6/(8,3145*293) = 13,7E-3 mol air
The total amount of gas after the reaction will be:
13,7E-3+25,6E-3 = 39,9E-3 mol gas
The pressure inside the bottle, assuming the temperature remains the same:
p = n*R*T/V
p = 39,3E-3*8,3145*293/330E-6 = 2,90E5 Pa
This is allmost 3 bar, the bottles have to withstand (at least) 5 bar
This is why the bottle, unfortunately, remains in tact.
Watch my next video for the same experiment, but this time with a bottle filled with water! Will it survive too?
next video:
http://www.youtube.com/watch?v=gHItDCnCLs8