[GBC] Akiyuki Train System: Type 2 mods and improvements

[Courbet]

4 minutes ago, 9v system said:

hi there do you have the sub models for the strainwave gearing?

May I ask what specific part you need and why?

[9v system]

Just now, Courbet said:

May I ask what specific part you need and why?

i need the hopper and the steps, because im building berthils ball shooter marble run module and this will save me some time.

[doug72]

1 hour ago, Courbet said:

For anyone who wants to easily try Doug's version of Akiyuki's Rotary Dumper, I have made building instructions of my own version, which is basically @Doug72 's rotary part (as modelized by @dunes ) mated with an adapted Akiyuki base.

Comparing to the inventory of the original Rotary Dumper, apart from a small bunch of common Technic parts 8 more yellow curved gear racks and 8 more 20t gears are needed and above all a 56t Turntable (60t is not an option!).

https://bricksafe.com/files/Courbet/akiyuki-project/gbc-train-est/GBC_Rotary_Dumper_Akiyuki_Doug.pdf

Many thanks for making the PDF instructions and the stipulation a Z56 Turntable MUST be used.

Doug

[MajklSpajkl]

3 hours ago, Doug72 said:

Elevator speed

=========================================

Re Rubber bands.
 

Yes, I think your math is fine :-) I am just a bit sad, that my motors obviously can't provide decent enough performance in 20:12. They usually stall on top when the stopping mechanusm is disengaged... ah well, I'll get over it :-)

I thiink you are right on the rubber bands as well. I am using non-LEGO braiding rubber bands for girls and after a couple day they seem to lose some tension indeed. Will follow you advice to take them off when not in use.

@Courbet Thank you very much for making pdf instructions - thy will come very handy, althoug I've already built the module. but he file or the folder sem to be unaccessible.

Best regards!

[doug72]

36 minutes ago, MajklSpajkl said:

Yes, I think your math is fine :-) I am just a bit sad, that my motors obviously can't provide decent enough performance in 20:12. They usually stall on top when the stopping mechanusm is disengaged... ah well, I'll get over it :-)

I thiink you are right on the rubber bands as well. I am using non-LEGO braiding rubber bands for girls and after a couple day they seem to lose some tension indeed. Will follow you advice to take them off when not in use.

@Courbet Thank you very much for making pdf instructions - thy will come very handy, althoug I've already built the module. but he file or the folder sem to be unaccessible.

Best regards!

Have you done the train mod to that uses a 9L axle between the two wheel axles drives ?
The M motor runs much freer than the original design which used a 5L axle with stop  + 2L axle joiner + 4L axle with stop.

Edited September 23, 2018 by Doug72

[Courbet]

54 minutes ago, MajklSpajkl said:

@Courbet Thank you very much for making pdf instructions - thy will come very handy, althoug I've already built the module. but he file or the folder sem to be unaccessible.

Someone else have problem to download the pdf file?

Edited September 23, 2018 by Courbet

[dunes]

No. Already built it from the instruction.

[doug72]

5 hours ago, MajklSpajkl said:

They usually stall on top when the stopping mechanusm is disengaged.

When you say the train is stalling leaving the upper level, is the train motor still running ?
I think the problem is you need more gear rack sections so that the 8T gears on the rear axle engage the rack to push the train off the elevator enough to engage with the gear rack on the bridge section. I had some problems with this as well.

Photo shows how I arranged them. They have to be arranged with a half stud offset.

Edited September 23, 2018 by Doug72

[MajklSpajkl]

8 hours ago, Courbet said:

Someone else have problem to download the pdf file?

Sorry, my bad, false alarm  The file is all accessible. Thx again!

@Doug72:

No, no, I wasn't clear I guess. The motors stalls when the platform reaches the height where the stopping 'chalks' need to be lowered. The cart pushes against them so much so they dont low down because the motor stalls before that. Sometimes I it barely gets to the too even without the problme with loweringvthe stops. Otherwise I have the same setup of gear racks except I left out the upper left and the lower right on the photo. So if the stoping mechanism manages to low down, the cart leaves the platform with no problem. But all that only with 20:12 setup. With 16:16 works like a charm :-)

 

[doug72]

10 hours ago, MajklSpajkl said:

No, no, I wasn't clear I guess. The motors stalls when the platform reaches the height where the stopping 'chalks' need to be lowered. The cart pushes against them so much so they dont low down because the motor stalls before that. Sometimes I it barely gets to the too even without the problme with loweringvthe stops. Otherwise I have the same setup of gear racks except I left out the upper left and the lower right on the photo. So if the stoping mechanism manages to low down, the cart leaves the platform with no problem. But all that only with 20:12 setup. With 16:16 works like a charm :-)

Puzzling as why one gear combination works and the other does not.
It seems some adjustment is required to get the chock into correct position to hold the train but then freely release it.

Try limiting the lift of the chock (stopper) and shorten the counterweight arms until the chock still stays up until trip lever hits the trip pin.
Suggest change the 2 x 1 beam with pin / axle holes to a plain pin with a 1L beam.

see photos, which taken with module on its side.
Yellow circle shows arrangement to limit the lift of the chock.

Lever A prevents chock from rising too high, adjust setting at B by sliding the axle in or out. 1/2 L projection seems OK.
Same as the lower exit chock except it uses a 1/2 pin with stud for the lever to touch.

Hope this works out OK for you.

 

Doug

Edited September 24, 2018 by Doug72

[MajklSpajkl]

I think you might be right - my chocks may be a bit to high, so the cart kinda jams them and more power is need to lower them. And the power my cart lacks of :-) I'll try what you suggested, although I built the platform a bit differently and I don't have those longitudinal axles at all to adjust the rotation of the chocks. Thank you for your help. 

Best regards!

[doug72]

1 hour ago, MajklSpajkl said:

I think you might be right - my chocks may be a bit to high, so the cart kinda jams them and more power is need to lower them. And the power my cart lacks of :-) I'll try what you suggested, although I built the platform a bit differently and I don't have those longitudinal axles at all to adjust the rotation of the chocks. Thank you for your help. 

Best regards!

You could try to fit a stop on one of the counter weight arms to position the chocks.
Can you post an image of that section of your build.

On my build I only removed the redundent parts from the original Akiyuki design, really needs rebuilding to only essential parts, which probably will do when I replace the 3D printed gear worm gear case.

I used to have problems like this with the original design.

Regards

Doug

Edited September 24, 2018 by Doug72

[MajklSpajkl]

Sure @Doug72. Below the photos...

Top view...

Bottom view...

 

In case you wonder, I decided to attach levers to disingage the stopps on both sides to get better performace. I guess I could lose some more weight by removing one of the weights. Same on the other side...

Again top...

Side view with a cart pushing into the chocks...

Platform in topmost position...

I agree it could be much more optimized parts-wise but since time is not on my side, as our event, I am prepraing this for, is getting near, i'll settle :-)

Still, very uch eager to hear your thoughts.

Best regards.

[doug72]

Thanks for the photos -  suggest only one counterweight is needed for upper level, mine works fine with just one.
The redundent one could be them be used to limit the travel of the arm that lowers the chocks until trip arm releases the train.

 

Suggest use a pin 3L in location shown in your amended image below to stop the counterweight arm and then experiment with different small wheels on the pin to set the chock height.
Or maybe use the LEGO Technic Half Beam Cam (6575) which has diferent x holes on a fixed axle inserted at location shown and then try the cam in different positioins.

 

Edited September 27, 2018 by Doug72

[MajklSpajkl]

@Doug72, guess what? I think I'll try to add a counterweight system to the lift via a pulley crane on top of the lift to aid raising te platform. If the weight weighs somewhere between sum of masses of the platform and of the train cart full/empty-average the motor should work with much more ease, maybe even at higher gear ratio, and might also look very interesting... I guess we'll see :-) I know it's a deviation from the original, but I think it may actually work. 

[doug72]

Interesting idea, most real elevators and ship lifts use counterweight systems.

Would certainly ease the strain on the motor & give a faster speed & look unique.

Doug

Edited September 24, 2018 by Doug72

[MajklSpajkl]

1 hour ago, Doug72 said:

Suggest use a pin 3L in location shown in your amended image below to stop the counterweight arm and then experiment with different small wheels on the pin to set the chock height.
Or maybe use the LEGO Technic Half Beam Cam (6575) which has diferent x holes on a fixed axle inserted at location shown and then try the cam in different positioins.

Hmm, I'm not sure that I get what you mean... If I put a pin in the proposed place I'll lock the path of the counterweight. So the platform wouldn't lower  down anymore until it breaks that pin pr something else.

But I managed to lower the position of the chock in another way. I replaced the two yellow halfwidth +0+ liftarms that prevent higher rise of the chocks with Axle and Pin Connector Perpendicular 3L with 2 Pin Holes.   In this way the angle that this connector is allowing the chocks to rise is a bit smaller. Or I could also put a half pin with stud in the lower hole on the black Connector Perpendicular Double 3L - see the photo of the platform from bellow.

Now off to make a nice counterweight crane which won't mess the whole thing up :-)

Best regards!

[doug72]

19 minutes ago, MajklSpajkl said:

Hmm, I'm not sure that I get what you mean... If I put a pin in the proposed place I'll lock the path of the counterweight. So the platform wouldn't lower  down anymore until it breaks that pin pr something else.

You are correct, my mistake, thought that beam was on the elevator platform itself.

[MajklSpajkl]

Voila! I'm done 

Here's my "upgrade" of the Akiyuki's&Doug's&dunes' train lift. I tried to keep it as simple as I was able (and willing ).

 

As you can see in the photos there are 4 separate counterweights hung over pulleys with no mechanical advantages. I was dwelling on advantage of 2 for each pulley, but that would mean doubling the mass of the weights by 2. In that case the tower wouldn't have to be higher than it is in the "original" version. I wanted to keep weights as small as possible (size wise) and I think those cylinder half 2x4x4 are just perfect. But as you can imagine, even full volume of ABS this size wouldn't suffice...

...therefore (purist be advised, this may hurt your eyes) I filled it with steel rods. I was really lucky to get 28 mm diameter steel bars at our local hardware store, they fit perfectly! I spray painted them white, 'cause that was in the garage 

The end result is fantastic, although a bit surprising. The weight of the platform with cart filled with 50 (nevergonahappen) balls was about 650 grams and when empty about 580 g. I decided to add counterweights in total of around 600 g. In the end it sums up to 590 grams. Funny thing is, that now the lifts goes more easy up full, than down empty, which was a bit unexpected, since the counterweights weigh closer to the empty cart then to the full cart. Nevertheless, with full batteries and gear setup 20:12, the time spent to ascend and descend is about 12-14 seconds which is waaaaaay better than without counterweights (20-25 second) at the same gear setup. I haven't tried the gears 24:8, as I don't think it is needed. I had to change the lower exit chock to be the same as on the upper exit side. The old ones were to short and since some effort is needed to get down the lift, the gears would rattle to much, as they were not aligned properly. I shot a short video and will upload it soon. I hope you like it, I am super happy about the outcome. Thank you @Doug72 and @dunes for leading me to this end result!

Best regards, Miha

Edit: For those who might have missed it: countercweights are an addition to Doug72's and dunes' mod with worm gear driving mechanism of the platform.

Edited September 27, 2018 by MajklSpajkl
typos

[dunes]

This is an excellent idea. And very nice implemenation of an elevator counterweight. 

 

[MajklSpajkl]

Thx @dunes 

Here's a video...

 

Edit: For those who might have missed it: counterweights are an addition to Doug72's and dunes' mod with worm gear driving mechanism of the platform. I think only counterweigts without any other mechanism, that holds the platform at the top or bottom position, are not enough to make it work.

Edited September 27, 2018 by MajklSpajkl

[Berthil]

Very nice work and idea with the counterweights, excellent and simpler (and therefore more reliable) solution for entering and leaving the lift.
The counterweights prevent the lift from dropping down I assume? I can't see any other mechanism.

For counterweights one could use the metal balls also used as counterweight for the rotating dumper by Akiyuki if one would like to use 100% LEGO.
Not cheap though but I have eight of them so I might have a go and try this, I'm using the Lithium battery pack in the trains so less weight/balls is needed.

 

[MajklSpajkl]

@Berthil: Thanks  Actually, the counterweights are only helping the motor to lift the platform as they are balancing the weight of the platform and the train cart. It is the worm gear mechanism that is preventing the platform from falling, as it locks the position of the platform immediately when the train leaves the platform. It was proposed by Doug and enhanced by dunes a couple of posts back. It makes the lift module much more reliable. I guess I kinda flud the topic with my longer posts, so you've missed it, sorry for that 

Edited September 27, 2018 by MajklSpajkl

[doug72]

An excellent MOD , well implemented and looks the part.
The additional structure also adds rigidity to the elevator.

Reminds me of the Anderton Boat Lift in Cheshire  England which at one point in its history used massive counter weights to help raise & lower the boat caissons.
https://canalrivertrust.org.uk/places-to-visit/anderton-boat-lift-visitor-centre

I have been also trying how to do this on my elevator but with only two containers fro the weights, so probably will have to use Pb. (Lead) Intend to use your idea to improve my build.

Will also give the 24 : 8 gear a try to see what speed can be achieved.

Doug

 

7 hours ago, Berthil said:

The counterweights prevent the lift from dropping down I assume? I can't see any other mechanism.

There is a worm gear in the drive system which prevents the elevator from moving when the train exits and also its now impossible for it to suddenly drop.

Akiyuki rejected using a worm drive because of the slow operating speed.

All Akiyuki's trips, latches etc are no longer required & removed,  just two simple trip levers - see my earlier posts, plus @dunes & @MajklSpajkl.
The worm gear is in the elevator platform below the train.

Only problem was it slowed the elevator speed down a lot, hence I am using 20:12 step up gears at the moment without counterweights.

 @MajklSpajkl counter weight system takes the load of the M motor and enables better gear ratios to be used to increase speed.
 Could be even faster if use 24;8 gears which without the counterweights previously stalled the M motor.

Its fool proof.

Doug

[MajklSpajkl]

Thank you @Doug72, I am glad you like it. Indeed the structure is much more solid now. I was also thinking about lead but I imagined it would be harder to get the shape for those half cylinder pieces I went for so didn't even look into availability of it.

Btw.: That Anderton boat lift looks amazing piece of engineering! Have you been there?

Best regards,

Miha