And thanks Martin for trying out my prototypesDivide By 4 & FishStair combo - MMX simplificationRossero Bertolli2021-02-28 | Multiple problems with the recirculating systems come from the fact that the divide by 4 and the fishstairs have to work in sync but that they are two unlinked seperate systems. Both the fishstair and divide by 4 always have to process exactly four marbles to keep working in harmony.
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=8Escape Wheelson ππ (MMX gate / dropper)Rossero Bertolli2021-02-27 | Look at him, he is so happy ππEscape Wheel marble dropper - MMX gate designRossero Bertolli2021-02-25 | This is a possible redesign for a gate/dropper combo that uses an escape wheel to reliably lock 'n load a marble every time a marble is dropped.
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)
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.nlA better divide by 4 for the MMXRossero Bertolli2021-02-14 | This divide by four uses a rolling marble as a counterweight, this ensures that the system only tips when there are 4 marbles loaded but ONLY tips back when the system is completely emptyPressure relief system MMX marble gate (compact, friction free)Rossero Bertolli2021-02-11 | This is a very compact system on top of the marble gates that can relief virtually all pressure on the gate, removing the need for a friction based marble maze.Fishstair springsteel Catcher mechanismRossero Bertolli2021-02-06 | This video shows how a redesign of the fishstair entry can resolve the 'marble hopping along', marble pinching and marbles coming in too fast in an empty que at the same time. See discord for more detailsNewtons cradle Marble energy dissipationRossero Bertolli2021-02-05 | ...Divide by 2 MMX prototypeRossero Bertolli2021-02-05 | This can by part of a two tier system to divide evenly by 4Adjustable hight modules MMXRossero Bertolli2021-01-31 | This video shows my take on adjustable height modules, with offset setscrews so both can be reached from the front of the machine with all the marbles in placeCurved marble track testRossero Bertolli2021-01-28 | ...Curved marble catcher testRossero Bertolli2021-01-28 | In this video I compare two different versions of the curved marble path, one with a rolling surface at 20 degrees and one at 25, the latter should push the marbles harder into the gates but also increase the risk of stuck marbles.
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.ZigZagZig MMX marble divider height regulatorRossero Bertolli2021-01-26 | This is my improved proposal to even out the marble height at the marble divider. This zigzag(zig) module always has the exact height at the top, no matter the position of the marble stack below. It has no moving parts and relies solely on gravity, making it impossible to have jams within the systemZigZag MMX testRossero Bertolli2021-01-25 | A "latchless" gate system that ensures a constant height for the top marble
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.proto 0.3Rossero Bertolli2016-04-08 | ...Mean machine centriproRossero Bertolli2016-04-08 | ...1e start nieuw chassisRossero Bertolli2015-12-12 | ...Mounting galvanized 2cv body onto its chassisRossero Bertolli2015-08-03 | Rejoining the chassis and the body during restauration
Music: Louane - Maman (LoΓ―c Coppola Remix)How to place a rivet nut without special tools (CitroΓ«n 2cv rear fender)Rossero Bertolli2015-07-31 | This video shows the steps to insert a rivet nut without any expensive tools. The only 'special tool' needed is a strip of metal with a hole to prevent the rivet nut from rotating. In this case I insert the rivet nut into the body of a 2cv that I am restoring. Make sure to remove the original welded nut with an angle grinder or chisel before placing the rivet nut. Good luck!2cv met nieuwe cilinderkop startenRossero Bertolli2013-11-22 | ...MonoskiingRossero Bertolli2012-05-03 | Trial and error, first attemptCitroen AZ eerste ritRossero Bertolli2011-09-10 | Hij rijdt!! nog wat deurtjes en hij is afEerste start van mijn Citroen AZRossero Bertolli2011-08-18 | Gister de AZ voor het eerst gestart. Van origine een 13,5PK motorblok, maar vervangen door een moderne variant!Throwing burning candle-grease in the air, creating a fireballRossero Bertolli2011-03-23 | We melted tealights in a little pan in the campfire. When it started burning I took it out of the fire and threw it in the air.
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 mounted on bike, going shopping, testvideo part2Rossero Bertolli2011-02-26 | Camera: 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 mounted on bike, going shopping, testvideo part1Rossero Bertolli2011-02-26 | Camera: 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)Firecracker experiment in beer bottle filled with waterRossero Bertolli2010-11-25 | This is part two of an experiment I did for my study to be a science teacher. 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
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?
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
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?