Gearboxes With New Orange Selector & 20z Clutch Gear

[Didumos69]

On 7/8/2018 at 2:39 PM, Attika said:

Well, while the conscious me wasn't gonna go for symmetry, the subconscious me just could not let it go. The strange mixture of this psychological nonsense resulted in a non practical but symmetrical layout. Please take it as a thought experiment:

Nice attempt! I hope I did not contaminate you with the symmetry-virus .

I tried this layout for a AWD with one rotary catch, but ran into the problem that the auxiliary driving ring inserts into the differential too deep, causing the driving ring to slip in the 16t clutch gear at the other end.

Does anybody know whether the new red 4L differential is different from the old one? Do the new 3L driving rings insert into the red differential as deep as in the red clutch gears, or deeper? In the old DBG version they insert deeper.

Edited July 9, 2018 by Didumos69

[suffocation]

@Didumos69 As far as I can tell, the two diffs are structurally identical. But I don't have much of an eye for detail, so let's see if anyone more eagle-ly inclined can pitch in.

Edited July 9, 2018 by suffocation

[Sariel]

As I pointed out when the red diff was first released, there is a subtle difference:

[Didumos69]

13 minutes ago, Sariel said:

As I pointed out when the red diff was first released, there is a subtle difference:

Thank you @Sariel! Could you also check if this has consequences as to how deep the 3L driving ring inserts into this side of the differential?

[Sariel]

Sorry, I only have one and it's buried deep inside a MOC.

[Attika]

2 hours ago, Didumos69 said:

how deep the 3L driving ring inserts into this side of the differential?

Bad news, no difference. it sits up on the outer collar and that is exactly the same as the DBG

 

Good news:

 

Edited July 9, 2018 by Attika

[Didumos69]

47 minutes ago, Attika said:

Bad news, no difference. it sits up on the outer collar and that is exactly the same as the DBG

Good news:

Thanks @Attika! Then I will use the old driving ring and old clutch gear. I might even be able to shorten the setup so I won't need the extension ring.

[Didumos69]

So in my line of gearboxes with rotary catches, here is my centered heavy-duty 4-speed AWD transmission with single rotary catch. It's not small, but it can handle a lot of torque and runs extremely smooth. Thanks @Attika for the info about the old driving rings. They insert a lot deeper, so no slipping occurs this time. Ratios are 4:15, 8:15, 15:16, 15:8 (0.27, 0.53, 0.94, 1.88).

Edited July 10, 2018 by Didumos69

[1963maniac]

Hey Didumos, That looks great! Do you have any LDD files yet. I ordered again from Lego for more of these parts. I'm learning a lot. I still have a hard time following the active gears in a given speed. After the 3rd or 4th gear pair it starts to get confusing, especially when everything is spinning. I guess if I build enough of these things it will start to sink in. Can't find a tutorial that speaks about gear train or is it drive train or maybe both are correct.

BTW i've been working on making BI for these gearboxes of yours. About the time I was getting done with one, You had to go and make a better version (2L shorter). Just kidding! I enjoy the process.

Edited July 10, 2018 by 1963maniac
added more

[Didumos69]

14 hours ago, 1963maniac said:

Hey Didumos, That looks great! Do you have any LDD files yet. I ordered again from Lego for more of these parts. I'm learning a lot. I still have a hard time following the active gears in a given speed. After the 3rd or 4th gear pair it starts to get confusing, especially when everything is spinning. I guess if I build enough of these things it will start to sink in. Can't find a tutorial that speaks about gear train or is it drive train or maybe both are correct.

BTW i've been working on making BI for these gearboxes of yours. About the time I was getting done with one, You had to go and make a better version (2L shorter). Just kidding! I enjoy the process.

I'll share LDD files tomorrow.

All my 4-speed sequential gearboxes without reverse - and the ones from many other designers too - follow the same approach. The input is split into two input axles - typically rotating in the same direction - with different gear ratios, giving them different RPM. The driving rings are attached to these two input axles. The clutch gears at the front and back side of the driving rings make a second gear ratio with the output axle, either directly or via auxiliary output axles - also rotating in the same direction - that are joined into the main output axle. In the centered gearboxes I showed in this thread, the left-right RPM ratio of the two input axles is 2, one turns twice as fast as the other.

Regardless of how the driving rings are controlled, with links and the old catches, or with the new rotary catch, sequential shifting always follows the same pattern over subsequent shifts: left side engaged, right side engaged, left side engaged, right side engaged etc. So with one shift, the engaged side always switches from left to right or from right to left. At the same time it follows this front-side-engaged/back-side-engaged pattern: front, front, back, back, front, front, back, back, etc. So every two subsequent shifts it switches from front-side-engaged to back-side-engaged or vice versa.

Now to obtain 4 speeds in the right order, you have to make sure the left-right jumps, which occur every subsequent shift, make a smaller gear ratio difference than the front-back jumps, which occur every two up-shifts. In other words, left-right has to make the minor ratio difference and front-back has to make the major ratio difference. This way, the minor ratio difference makes the difference between 1st and 2nd gear (one up-shift), the major ratio difference makes the difference between 1st and 3rd gear (two shifts) and combined they make the difference between 1st and 4th gear (two + one shifts).

The major ratio difference being bigger than the minor ratio difference ensures that when you switch from 2nd to 3rd gear, you drop less RPM by switching between the left and right driving rings than you gain by switching between front and back clutch gears. So for the front-back jumps in the centered gearboxes I showed in this thread, I use a front-back RPM ratio that is bigger than 2. In the AWD transmission it is in fact 3.52.

I hope this makes sense.

Edited July 11, 2018 by Didumos69

[Didumos69]

14 hours ago, 1963maniac said:

Do you have any LDD files yet.

Here are the LDD-files I have. Btw, I refer to a gearbox as heavy-duty when the output-axle is sandwiched by the auxiliary output axles. This will reduce the chances of slipping.

• Simple sequential 4-speed gearbox with single rotary catch, video: https://youtu.be/kqlaKH_oLsc
• Centered heavy-duty sequential 4-speed gearbox with single rotary catch, video: https://youtu.be/vCwiEUTxCrg
• Centered heavy-duty sequential 4-speed AWD transmission with single rotary catch, video: https://youtu.be/OSuf6UZWp7k
• Sequential 8-speed transmission tunnel with rotary catches and 8-to-1 gearblock, video: https://youtu.be/b5zdYGAGlec

I'm still working on a centered sequential 3+R gearbox with single rotary catch.

Edited July 11, 2018 by Didumos69

[1963maniac]

Didumos69, Thank you so much for the LDD files. Is this "Tunnel" the same as your previous "short" version? Yes, your explanation makes sense, I got that, but I need to see it too. Yesterday, I was thinking  about, for example how Blakbird on "Technicopedia" colors all the gears involved for speed 1 & then colors speed 2 a different color & speed 3,etc. Sariel does it in his book too. But on these wonderful sequential transmissions I want to learn how it goes when changing from one speed to the next. I'm a visual and tactile learner. I need to see it and get it into my hands. Using your LDD files helps with that. I would guess most most AFOLs learn like me. Anyways, Thank you for all the pictures and 3D files in this thread. I open them in Stud.io, then export them as LDRAW and work on them in MLCAD, then LPUB3D, Crazy, huh!? I did the 4 speed centered and was working on the tunnel but I will start again on this version and these other three. I'm trying to become proficient at making Building Instructions.

[1963maniac]

Didumos69, There may be a mistake in your LDD file for Centered HD 4 speed AWD.. The red 16t clutch gears have a space between them and the transmission driving rings.

[Didumos69]

2 hours ago, 1963maniac said:

Didumos69, There may be a mistake in your LDD file for Centered HD 4 speed AWD.. The red 16t clutch gears have a space between them and the transmission driving rings.

That is where the new yellow extension rings go. You can see them in the  video. They are not available in LDD and I forgot to add placeholders.

[Jack Bloomer]

@Didumos69 when you make the housing for the 3+r can you use as little I-Beams as possible. I only have two and I still haven’t figured out how to use them right. 

Is it possible to make a 3+r with the new selector but not centered? Kinda like your first 4 speed gearbox but with a reverse. 

Edited July 11, 2018 by Jack Bloomer

[BusterHaus]

@1963maniac Make sure you use the latest ldraw.xml file for converting the LDD files, it solves a lot of headaches. 

https://www.eurobricks.com/forum/index.php?/forums/topic/137193-more-up-to-date-ldrawxml-lddldraw-conversion-file/

[Jack Bloomer]

Nvm. I figured it out. I would put pics but it won’t let and I don’t have all my parts yet so it is a little bare bones

Edited July 11, 2018 by Jack Bloomer

[Didumos69]

3 hours ago, Jack Bloomer said:

@Didumos69 when you make the housing for the 3+r can you use as little I-Beams as possible. I only have two and I still haven’t figured out how to use them right.

I will use 2 of these dog bone pieces.

3 hours ago, Jack Bloomer said:

Is it possible to make a 3+r with the new selector but not centered? Kinda like your first 4 speed gearbox but with a reverse.

I'll look into that, but I fear it won't be as small as that 4-speed gearbox.

[Jack Bloomer]

@Didumos69 I really like the design. When I finished my version it was about two studs wider but that’s it. Other than that it works pretty much the same way. Thanks for using only two dog bones. Really helpful

[1963maniac]

5 hours ago, BusterHaus said:

@1963maniac Make sure you use the latest ldraw.xml file for converting the LDD files, it solves a lot of headaches. 

https://www.eurobricks.com/forum/index.php?/forums/topic/137193-more-up-to-date-ldrawxml-lddldraw-conversion-file/

Thanks for the tip. I use Stud.io to convert LDD to LDRAW and haven't had any headaches yet.

[Jack Bloomer]

I have a challenge for anybody (I don’t have enough parts to even try and my computer is terrible). Make a 6 speed gearbox or 5+r with one or two rotary catches. I honestly don’t even know if it is possible knowing the nature of the catch

[Didumos69]

On 7/11/2018 at 10:41 PM, Jack Bloomer said:

@Didumos69 I really like the design. When I finished my version it was about two studs wider but that’s it. Other than that it works pretty much the same way. Thanks for using only two dog bones. Really helpful

Here's my centered sequential 3+R version. Ratios are 1:2(R), 1:2, 1:1 and 2:1. LXF-file here.

[Jack Bloomer]

This video got me out of bed. I was thrilled to see it. Really Good Job designing all 5 gearboxes 

[allanp]

23 hours ago, Jack Bloomer said:

I have a challenge for anybody (I don’t have enough parts to even try and my computer is terrible). Make a 6 speed gearbox or 5+r with one or two rotary catches. I honestly don’t even know if it is possible knowing the nature of the catch

It's technically possible with one rotary cam shifter as it only takes 60 degrees of rotation to change the state of a drive ring. However you would have to arrange 3 drive rings in a triangle around a central rotary cam shifter. I've not tried this myself as my parts are buried inside a Chiron. Doesn't sound like the easiest of challenges though. 

[Didumos69]

5 minutes ago, allanp said:

It's technically possible with one rotary cam shifter as it only takes 60 degrees of rotation to change the state of a drive ring. However you would have to arrange 3 drive rings in a triangle around a central rotary cam shifter. I've not tried this myself as my parts are buried inside a Chiron. Doesn't sound like the easiest of challenges though. 

You could do that, but I fear you would run into double engaged clutch gears during shifts. 30 degrees (a half shift) won't be enough to disengage the driving ring.