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Hi Egypt :)
I will be holding a short gearbox assembly tutorial in 15 minutes
No need to bring anything - we will just design gearboxes, which does not cost anything
Also, you need to make sure that you are actually able to use the gearbox table - you need the Automation skill to be able to use it
I'd like to show you a nice web page that we are going to be working with today:
http://www.silverchat.com/~silver/atitd/gear.cgi
(dead link) This is a gearbox simulator - we will look into this later to see how it works.
We will start with some theory:
Your gearbox table has an 8x8 grid.
Within this grid, you can position gears to influence the values of your gearbox.
If you already find a design on the table, you might destroy somebody's design by clicking "Clear the Table", but you will not be wasting any resources.
Once you are at the table, open up the menu and sticky it somewhere.
Take a look at the menu: you have the option to add several types of gears.
3-tooth and 4-tooth mean small gears
5-tooth and 6-tooth are medium gears
The 7-tooth is a large gear, so we will want to avoid that one :)
Next option is a spacer, we will come to that later.
Analyze tells you what your current gearbox does, so we will be working with this one a lot.
Let's click analyze and see what it says.
It tells us that the design is not a legal design, and it wants something at 1A.
Aha ;)
Close that message, we will understand what this all means soon :)
If there is anything on your table and you want to get rid of everything, you use the next option: Clear the Table.
Cursor down, left, right, up lets you move within the table.
Let’s play with those options
You should see a whitish stick at "1A".
This stick determines what part of your grid you are currently working on, so if it’s at 1A right now, you can add gears in this spot, or remove gears, for that matter.
So lets move that stick around a bit, and if you like, you can add a few gears.
There’s a question about the best zoom: I like to use F7 zoomed in quite a bit.
So play with that white stick, move it up and right a bit, and add gears haphazardly. We will clear the table later on for a clean start.
Djehuty is saying he prefers F5 for a zoom.
I'll try that now too :)
Yes, F5 works just fine as well.
You will be moving that stick around quite a bit, so those keys might be good ones to remember as hotkeys later on, but for now, it's just fine to use the mouse.
Someone is having difficulties with hotkeys.
Let's quickly check the hotkey settings (no need to do this if yours are working just fine):
Go to Utility -> Chat related.
Make sure that "Chat and Inventory can be minimized" is activated.
I also like to activate the option just below that one - it enables you to keep on reading E! while working with hotkeys.
To switch on your hotkeys, hit Enter.
Now make sure that the mouse cursor points at your gearbox table, and then you should be able to use the hotkeys :)
Seems to be working now, great.
Okay, some of you may already have covered the entire table with gears – let’s clear the table and start with a proper design.
Click "Clear the Table", and move the white stick back to A1.
We will start with a somewhat boring design, only using small gears, so it’s boring and cheap :)
Add a 4-tooth in that A1 spot, then move the stick to B2, and add another 4-tooth.
Next will be C3 for the next 4-tooth.
Now you should have 3 gears in a neat diagonal row.
Let’s take a look at this via "Analyze".
Now it's telling us that 1A, 2B, and 3C are all rotating at 100%.
Let's complete this row to the top right, just keep adding 4-teeth.
Your last 4-tooth should be at H8, or 8H (somehow I prefer H8, but the gearbox table wants 8H).
Analyze this thing again :)
Surprise surprise, youve got more shafts, and they are all rotating at 100%.
The gearbox you have just designed is a H100 gearbox.
Any idea why it would be called this?
For a gearbox to be complete, it has to have something in row 8; and not just anything at all, but something that rotates there.
8H rotates because it is fully connected to 1A (bottom left corner), so you could imagine that there is a little motor at 1A. This motor rotates at 100% speed.
With the gears, you can change this rotation from shaft to shaft (we will do this later).
Because we only used gears of the same size, everything rotates at 100%.
There is only one gear in row 8: the top right one (column H), so H100 means that a gear in 8H rotates at 100%.
Let’s make this just a little bit less boring:
Add another 4-tooth in F8, and analyze the thing again.
Now we have 2 shafts in row 8, both at 100%.
Make sure that you don't carry any gears on you, then click "Build This Gearbox" (you won't build it).
It tells you what this model would be called: F100 H100.
It has a 100% shaft both in F8 and in H8.
One question: Do all gearboxes have to end in the 8th row? Yes, and it has to be connected to 1A.
Let's add a 4-tooth in 8C, and analyze again.
You will see that nothing is rotating in 8C. That's because 8C is not connected to 1A through gears.
Okay, it seems that people want to build something that's not 100% now.
Let's do that - clear the table, bring the white stick back to 1A.
Now let's play with the expensive stuff - add a 5-tooth please (which would be a medium gear).
Each gear can only be connected with other gears in certain patterns.
A 5-tooth cannot be connected with a 4-tooth - it simply won't fit.
But it can be connected with a 3-tooth.
Move the white stick to 2B and add a 3-tooth there, then hit analyze.
Questions about how they fit or don't fit:
Let's try adding a 4-tooth right on top of that 3-tooth - 3B. Then hit analyze again.
You should get a message that two gears are too close to each other.
When the gearbox table talks about the "cursor", it means the white stick by the way.
So in this case, the 3-tooth and the 4-tooth are jammed. It won't work this way.
There are several things you can do about this, but we will come to this later.
For now, remove the 4-tooth and replace it with a 3-tooth.
Hitting analyze should tell you that 1A is at 100%, 2B and 3B are at 167%.
Okay, it seems some people are stuck: You should have a 5-tooth at 1A, a 3-tooth at 2B, another 3-tooth at 3B.
Now complete the line of 3-teeth up to 8B.
If you hit "Build this gearbox", it will tell you the name and the cost of this gearbox:
7 small gears, 1 medium.
Let’s clear the table again and start a new design at 1A
Start with a 6-tooth this time, that’s still a medium gear.
6-teeth can be combined with 5-teeth, so let’s do that - add a 5-tooth at A3, and analyze please :)
Should be 120%.
We know from the last design that 5-teeth go together well with 3-teeth as well, so add a 3-tooth at 4B. You should now have a 200% gearbox.
You could complete the row of 3-teeth up for a valid design... do you want to do this or continue straight away?
Continue, okay... clear the design.
Let’s reverse this 6-5-3 box now, so start with the 3-tooth.
Any ideas where a 5-tooth could go now?
Great, B2 it is :)
Two possible places for the 6-tooth now... where are they?
Yes, B4 is one possible spot, but there is another...
D2, excellent!
Let's put one in each spot: one in B4, one in D2; now analyze this thing :)
So now youve got 50% in two places, using 3 medium gears.
If you were to continue your row from B4 up, how would you go about this?
You could try adding more 6-teeth... which would be quite expensive... and not sure if they will fit, you could try.
Has anybody found a valid spot?
Suggestion is 5-tooth at B6, let’s try that, then a 6-tooth at B8.
Yup, that works.
Another idea: 6-tooth at C6 and B8 - try that too please – this works too.
Next idea: 5-tooth at B6, then 3-tooth at C7, and 3-tooth at C8 - let's try that one.
Works, but you're back at 100% there.
Okay, somebody has discovered spacers now, so let's take a closer look at those now :)
So far, we have been working on one level - actually there are 3 of them.
So where we have put only one gear in one spot, there is space for up to 3 of them in one place.
With these 2 additional layers, you can change gear ratios within the same spot.
Let's start again with that 3-5-6 setup.
Now you could make this line longer using 3-tooth or 4-tooth gears.
Go to the place where you have your 6-tooth.
Add a 4-tooth on top of it.
The 4-tooth is the one that can be combined with another 4-tooth in a diagonal line, so C5 would be the right place for it.
If you add a 4-tooth right there, it would go in the first layer, and collide with the 6-tooth.
So what we do, we add a spacer.
Do that, then add your 4-tooth.
If you look carefully, you can see that the spacer is represented by something like a little ring.
That ring is like a little metal ring you put below your gear, so the 4-tooth goes in the second layer, and should work with that other 4-tooth in the second layer now.
So now you could continue that line to the top with 4-teeth and spacers.
Question: does the spacer cost anything when the gearbox is made? No, but it counts towards something else, we will discuss that later.
If you like, you can continue your line to the top now, otherwise, clear the table or play around with spacers for a bit more.
You could also put a 3-tooth below your 4-tooth in the next row (row 6), then continue in a straight line up.
In total, you can use up to 3 such layers.
There are two restrictions that are important for you when you are working with spacers and such.
One is that you cannot use more than 30 gears - spacers count towards this total!
The other restriction is that you cannot use more than 15 shafts total.
When you are working with 3-output gearboxes, you will reach these limits very easily.
This session is only for beginners, so we will not go into how not to waste gears or shafts in this session.
What's a shaft? yes, it is a spot that has gears.
Now, i think you understand how the basic mechanics go, but....
How to construct a gearbox according to certain specifications?
Hehe, there's been a question what is a random-output gearbox? it's more or less what we have done so far...
Now how do you predict what your gearbox will do?
There is this web page i have told you about in the very beginning...
http://www.silverchat.com/~silver/atitd/gear.cgi
(deadlink) Let's take a look at that one
the situation is usually that you are required to build a gearbox that has something like A450-500 D90-120 H30-200, or something like that.
Those 450-500 things are ranges.
On the page, you see two boxes with the heading "box 1".
Enter 450 in the first field, 500 in the second, then click submit.
It gives you several suggestions how to achieve a ratio between 450 and 500.
The first one costs you 3 medium gears and gives you a ratio of 463.
Let's clear the table and build that one... let's say that output has to go to column A.
It says 53 * 53 * 53
So if you combine 5-tooth and 3-tooth three times, you will arrive at that ratio.
Please play around with this a bit before i give you a possible solution.
Okay, here is a solution (i'm not saying this is the best or the only solution):
A1: 5-tooth
B2: 3-tooth, then 5-tooth
A3: spacer, then 3-tooth, then 5-tooth
B4: 4-tooth, then spacer, then 3-tooth (the 463 ratio is now achieved)
A5: 4-tooth
B6: 4-tooth
A7: 4-tooth, then 3-tooth
A8: spacer, then 3-tooth
Does anybody have another solution, or maybe someone is stuck?
Question about what 53*53 means...
53 is a shorthand for combine a 5-tooth with a 3-tooth, then do the same again.
Okay, let's go through the solution together, and see what this has to do with what’s said on the web page.
We wanted a gearbox A450-A500, so anything between 450 and 500 is okay on A8.
We entered 450 and 500 as the lower and upper limit of our ratio.
Web page says 53 * 53 * 53 gives a ratio of 463.
53 means take a 5-tooth and combine it with a 3-tooth, so we put 5 on A1, and 3 on B2 – that’s the first 53.
Now for the second 53, we do the same again, starting at B2... put a 5-tooth on top of the 3-tooth on B2.
We need to combine this one with another 3-tooth, which is what we do at A3.
But we need to do this on the second layer, so we put a spacer first.
For the third 53, we need to do another 5-tooth/3-tooth combination, starting at A3 now, so we stick another 5-tooth on A3, which lets us end up in layer 3.
So for B4, we would put 2 spacers, then a 3-tooth; only that with 2 spacers, we would not have any more space left.
We could continue this line up now with only 3-teeth and lots of spacers.
This would be totally valid and probably save a few gears too, so lets try this...
Go to B5, put 2 spacers and a 3-tooth.
You would end up at B8.
From there, you could put another 2 spacers and a gear on A8, and end up with a 2-output gearbox, 463 on A8 and B8.
If you wanted to save that B8 spot (maybe because you need to fill 2 other slots with different ratios), you could add a 4-tooth at B7, then go in a diagonal line to A8.
Again, how to save on gears is the true art of gearbox design, and we are not going to go into this today.
This should give you the tools to play with gearbox tables and try out some designs - there are many possible ways of perfecting your design.
Question: why doesn't the 4-tooth and 3-tooth change the percentage?
Your last change in percentage was at B4, from the 5-tooth to the 3-tooth.
Here, you combine two different gears to change your percentage.
From then on, you combine same with same, which does not change anything, so if you stick a 4-tooth on top of a 3-tooth, and then continue with another 4-tooth, the two 4-teeth are combined, not the 3-tooth and the 4-tooth.
Another question: Can I give you actual gearbox examples? Yes :)
There are some examples from T1.
If you go to the link from the page I showed you: "See also: Wiki: Gearboxes".
In the bottom of that page, there are a few example designs, there are some 2-output and some 3-output ones.
If you like, you can reconstruct those designs to see how they work.
Otherwise, you could just make up a few designs on your own - the numbers they want are usually between 5 and 600.
So make up a letter and a number range, and enter that in the gearbox simulator page, then see if you can build that design.
Start with something easy (just 1 output), then try a second output if you like :)
Okay, that's it for now, thanks for your participation :)
One last question: Are 3-output boxes the highest requirement? Yes, no 4-output ones yet :)

Assignments (solutions are linked on this separate page):

First design (easier): B143-B172 E233-E280 G437-G542
Second design (difficult): A206-A249 E131-E164 G275-G333

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Last edited March 14, 2006 9:15 pm by Vraitak (diff)
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