The Gearbox

[PerryMakes]

It seems that back in the Technic Brick days there was a trend of parts being produced specifically purposed for housing gears (perhaps out of necessity?) I was unaware of this until these two showed up in a *Power Miners set:

Technic, Gearbox 2 x 4 x 3 1/3

Technic, Gearbox 4 x 4 x 1 2/3

I find the first one to be absolutely amazing! One of the things that's bugged me since my first Technic set was the **play that's found in each and every brick-built solution for housing worm gears. Most of the time, the excess movement is due to the gear sliding back and forth in its housing - and this gearbox alleviates that problem by holding the worm gear nice and tight! But I don't see anyone using these gearboxes at all ... is that because they do not share my OCD condition??? Not wanting to be limited to a specific ratio would be my best guess...

Can you think of any other situations where using a part-specific gearbox would benefit the overall functionality?

Cheers ~ Perry

* try hard to not point and laugh ... (a) being fairly fresh out of the Dark, I'm grabbing anything I can get my grubby hands on! (b) I found these sets for pennies on the dollar during the unfortunate demise of Borders book store.

** if this phrase finds itself lost in translation, I'll further explain what I mean by this: Let's you have some function being controlled by turn a 12t gear - and somewhere in the chain of things there is a worm gear. I find that when the worm gear is housed in a brick built structure (even the BEST that are recommended by expert MOCers) - you can rotate that 12t gear back and forth a certain amount and get no resulting action at the end function.

Edited September 21, 2011 by PerryMakes

[Sokratesz]

It seems that back in the Technic Brick days there was a trend of parts being produced specifically purposed for housing gears (perhaps out of necessity?) I was unaware of this until these two showed up in a *Power Miners set:

Technic, Gearbox 2 x 4 x 3 1/3

Technic, Gearbox 4 x 4 x 1 2/3

I find the first one to be absolutely amazing! One of the things that's bugged me since my first Technic set was the **play that's found in each and every brick-built solution for housing worm gears. Most of the time, the excess movement is due to the gear sliding back and forth in its housing - and this gearbox alleviates that problem by holding the worm gear nice and tight! But I don't see anyone using these gearboxes at all ... is that because they do not share my OCD condition??? Not wanting to be limited to a specific ratio would be my best guess...

Can you think of any other situations where using a part-specific gearbox would benefit the overall functionality?

Cheers ~ Perry

* try hard to not point and laugh ... (a) being fairly fresh out of the Dark, I'm grabbing anything I can get my grubby hands on! (b) I found these sets for pennies on the dollar during the unfortunate demise of Borders book store.

** if this phrase finds itself lost in translation, I'll further explain what I mean by this: Let's you have some function being controlled by turn a 12t gear - and somewhere in the chain of things there is a worm gear. I find that when the worm gear is housed in a brick built structure (even the BEST that are recommended by expert MOCers) - you can rotate that 12t gear back and forth a certain amount and get no resulting action at the end function.

I don't think that these two parts have been used in official LEGO sets for some time now, and there are many other ways of securing worm gears and bevels in place so they won't slip :)

- Sok.

[AndyC]

I don't think that these two parts have been used in official LEGO sets for some time now, and there are many other ways of securing worm gears and bevels in place so they won't slip :)

The first was used in the 2011 set Battle for Geonosis and the UCS Imperial Shuttle, whilst the second appeared in City of Atlantis in 2011 too. They aren't much use in modern technic designs though, as they don't really integrate into studless designs well.

[efferman]

in studded times this part was very usefull for wormgear transmissions, but now we have other ways to do the same. there is no reason to use it not if the gearbox fits for your needs.

[Rufus]

It seems that back in the Technic Brick days there was a trend of parts being produced specifically purposed for housing gears (perhaps out of necessity?) I was unaware of this until these two showed up in a *Power Miners set:

Hi Perry,

Please try to stick to the default font, and size, for general text. Anything larger looks a bit 'shouty' and can put people off. Save the larger fonts for headings and such!

Thanks.

[PerryMakes]

Anything larger looks a bit 'shouty' and can put people off. Save the larger fonts for headings and such!

@Rufus -

The font you're talking about here has a size=3, which I don't think looks very large at all. This, of course, has everything to do with monitor size and resolution settings... In order to facilitate the software development that pays the bills, I require having anywhere between 2 and 102 apps running concurrently! That means a large lcd with a native resolution, so I guess my monitor/resolution must not be providing a good representation of what you're seeing.

I ALWAYS THOUGHT THAT THIS WAS WHAT PEOPLE USED WHEN THEY WANTED TO BE 'SHOUTY' (ugh... that was even quite terrible to just type the example!)

Anyways - I certainly don't want to be violating board policies... heaven forbid I get suspended from posting! There was something from Boneparte about image size limits, but that's all I can recall seeing with regard to site-wide policies and procedures... Could you perhaps point me in the direction of said policies?

Thanks ~ Perry

Edited September 20, 2011 by PerryMakes

[Blakbird]

It seems that back in the Technic Brick days there was a trend of parts being produced specifically purposed for housing gears (perhaps out of necessity?) I was unaware of this until these two showed up in a *Power Miners set:

Those gearboxes were widely used in the mid 90's in Technic sets, especially "Tech Play" which were designed to be easy to build for beginners. When LEGO switched to the studless system, they became less relevant for Technic sets but are still used in System sets. I talk about them a bit here and here.

[PerryMakes]

@Blakbird - thanks for the links. I've read both pages in the past, but must have passed over the comment about the worm gear being "a little less than 2 studs long." This is certainly the cause of the worm gear sliding back and forth resulting in a loose feel for that gear train. Like most things in life, I probably let this bother me more than it should ... it's just that this gearbox eliminates 99% of this excess movement, so IMHO the extra work/required space might just be worth it!

I'm tempted to ask for some suggested ways to bring this part into a studless build ... but that would be downright lazy.

[Wiseman_2]

I'm tempted to ask for some suggested ways to bring this part into a studless build ... but that would be downright lazy.

To be honest, it would probably require more effort to try and incorporate it into a studless build than simply doing it with connectors and liftarms. If you use bushings at either end of the worm gear, it shouldn't slip.

[Blakbird]

I'm tempted to ask for some suggested ways to bring this part into a studless build ... but that would be downright lazy.

There are many such ways. I just finished rebuilding Brian Cooper's Teknomeka. This massive robot weighs many kilograms (OK, technically weight is Newtons) and all of the joints are articulated with worm gears. If these joints had any slop in them at all, the whole thing would fall over. Brian uses a variety of methods (not including the subject gearbox) to remove play in the system and they are highly effective. Sadly, I cannot share any of them since the instructions are copyright, but rest assured that the methods are out there!

As for the gearbox itself, it was used in some late 90's early 2000's models that were mostly studless. It can be mounted with 3/4 pins instead of studs and suspended from other parts.

To be honest, it would probably require more effort to try and incorporate it into a studless build than simply doing it with connectors and liftarms. If you use bushings at either end of the worm gear, it shouldn't slip.

Bushings help, but they are an even 1/2 stud lengths so they can't fill the fractional stud gap. If you put enough longitudinal force on the worm gear, it will still slide and you'll get backlash in the system.

[mescalinum]

there's also this (two of those to make one worm gear housing)

...and probably also others

[Burf2000]

It seems that back in the Technic Brick days there was a trend of parts being produced specifically purposed for housing gears (perhaps out of necessity?) I was unaware of this until these two showed up in a *Power Miners set:

Technic, Gearbox 2 x 4 x 3 1/3

Technic, Gearbox 4 x 4 x 1 2/3

I find the first one to be absolutely amazing! One of the things that's bugged me since my first Technic set was the **play that's found in each and every brick-built solution for housing worm gears. Most of the time, the excess movement is due to the gear sliding back and forth in its housing - and this gearbox alleviates that problem by holding the worm gear nice and tight! But I don't see anyone using these gearboxes at all ... is that because they do not share my OCD condition??? Not wanting to be limited to a specific ratio would be my best guess...

Can you think of any other situations where using a part-specific gearbox would benefit the overall functionality?

Cheers ~ Perry

* try hard to not point and laugh ... (a) being fairly fresh out of the Dark, I'm grabbing anything I can get my grubby hands on! (b) I found these sets for pennies on the dollar during the unfortunate demise of Borders book store.

** if this phrase finds itself lost in translation, I'll further explain what I mean by this: Let's you have some function being controlled by turn a 12t gear - and somewhere in the chain of things there is a worm gear. I find that when the worm gear is housed in a brick built structure (even the BEST that are recommended by expert MOCers) - you can rotate that 12t gear back and forth a certain amount and get no resulting action at the end function.

I still use the first one quite a lot but don't have many of the second one. Added to Bricklink wanted list!

[mostlytechnic]

I've got some of the second that I'm using for making powered versions of the 7747 windmill. Helps tremendously in keeping the gears from slipping. But yeah, I can see where they're less common now that technic has gone all studless.