Sunset > Venery > Gearbox Design

As each gearbox is a separate table, we had to divide the list to get reasonable load times.

• AB Plus contains the first half of the designs.
• Except AB contains the rest of the designs.
• Trade Lists provides a nice list of available gearboxes, and we've provided an optimum design, and thereby a fair exchange value, for each of the 3-output gearboxes.

Optimum Design of 3-Output Gearboxes

As a rough guide, a random 3-output Gearbox is worth about 10K Goodscript. Assuming 6 Medium Gears and 12 Small Gears are used, that's 120 Iron at about 50 GS each plus 24 Brass at about 150 GS each. That's 9600 GS in raw materials, plus the cost of the Beeswax and Charcoal that's needed to cast the gears. You also need to make a small allowance for errors, labor, and profit.

Glass Rods are very likely to be an acceptable medium of exchange, as most of the folks who are good at mining and gearboxes are also involved in pyramids and therefore in prospecting for Tooth Limestone, which literally eats Glass Rods. As the price of Glass Rods hovers around 310 Goodscript, 9600/310 = 31 Glass Rods, which is conveniently the number of Glass Rods that you'll get from one run on a Glazier Bench. For planning purposes, a 3-output Gearbox is worth 31 Glass Rods.

Most gearbox designers prefer for you to simply bring the necessary gears, but if you have the gears, then you can easily build the gearbox yourself :-) You'll have to work out your own arrangements. Like most folks, we bought the 3-output gearboxes that we needed for our first few Raeli Ovens, and paid a bit extra for help in hauling the materials around.

Marble Quarries

The nice thing about quarries is that you can add a gearbox, or two, at any time and you can then recover the gearbox when the quarry collapses. You'll have plenty of time, so trading gearboxes (especially the ones that you can't use anyway :-) is quite practical.

• Without a gearbox you'll need four people to operate the gantry
• With one 1-output gearbox you'll only need three people
• With an additional 2-output gearbox you'll only need two people

The gearboxes that you see offered for trade have mostly been recovered from quarries. Although you only need 1 or 2 outputs for a quarry gearbox, it's a very good idea to toss in a couple of extra small gears and double the liklihood of reusing or trading that particular gearbox. If you know the gearbox requirements for several Quarries, it's also worth the effort to design 3-output gearboxes that you can use in a couple of different quarries.

Sunset Venery has the following quarry gearboxes available for trade:

• a30 c11 d50 (build 5m122)
• a400 b480 g400 (build 7m158)
• a13 b13 h400 (build 8m190)
• b13 d400
• b50 d60 g400 (build ??)(hounddog)
• b240 d240 f240 (build 4m94)
• b333 d333 g278 (build 4m106)
• b350 g175
• b386 c386 h278 (build 5m126)
• b463 f200
• b480 c480 f278 (build 8m180)
• c240 g400
• c322 d463 h463 (build 7m164)
• c556 e240 g144 (build ??)(hounddog)
• d200 h167
• d400 e400 g240
• f159
• f333

Quarries

We've arranged with OldJoe to work several quarries that are owned by Children of a Lesser Guild, for a royalty that will come out of the guild share. As usual, the split will be 1/2 to the guild, 1/2 divided equally amongst the workers. If you provide a gearbox, you also get the share for the gearbox.

We're developing following quarries:

**Location**	Stone	Primary	Pgear	Secondary	Sgear	Pulls
1603 2570	OSM	c297-330	c322 d463 h463	c436-510 g137-169	needed	0
1584 2510	OSM	h427-487	c322 d463 h463	a382-474 h405-454	needed	0
1581 2645	OSM	c11-12	a30 c11 d50	a355-415 g389-436	a400 b480 g400	25c
1554 2423	YA	d449-530	c322 d463 h463	c272-332 g229-277	needed	0
1545 2554	OSM	b467-560	b480 c480 f278	c488-547 f139-364	needed	0
1511 2371	WA	d45-50	a30 c11 d50	c430-499 f278-325	b480 c480 f278	14c
1500 2587	OSM	c212-254	c240 g400	a13-16 h348-404	a13 b13 h400	16c
1494 2448	MG	b68-76	needed	needed	needed	0

Raeli Ovens, Fountain Controllers, Cartouche, and Empty Hand Towers

When you build a Raeli Oven or a Fountain Controller, you'll only have two hours before the small construction site evaporates, to come up with a random 3-output gearbox. While you can reset the 2 hour timer by adding single items, the fundamental reality is that you must have the resources on-hand, or have made some other arrangement, to quickly create the random 3-output gearbox that you'll need for each Raeli Oven or Fountain Controller. You won't know the gearbox requirements until you build the construction site. On the other hand, if you don't like the required gearbox, you can always tear down the construction site and try again.

Two of the Cartouche buildings, Fall of Balance and Churn of Earth, require gearboxes.

The gearboxes that are required for Raeli Ovens, Fountain Controllers, and Empty Hand Tower blocks cannot be recovered.

• Each Raeli Oven and Fountain Controller requires a 3-output gearbox, and you can "shop" for an easy gearbox.
• Each block in an Empty Hand Tower requires a 1, 2, or 3 output gearbox, and you can't avoid building the specified gearbox.

The Raeli Oven, Fountain Controller, and Empty Hand Tower 3-output gearboxes are much harder to design than the 3-output quarry gearboxes, because you can't get the extra output by just tossing in an extra gear.

Cost

The traditional measure of cost ignores the small gears, counting as follows:

• 0 units per Small Gear
• 1 units per Medium Gear
• 6 units per Large Gear

We show that traditional cost, plus the actual cost in units of metal, but we'll continue to ignore the cost of charcoal, beeswax, equipment, and labor.

• 2 units of Brass per Small Gear
• 20 units of Iron per Medium Gear
• 120 units of Iron per Large Gear

The cost for a gearbox with 6 Medium Gears and 12 Small Gears will therefore be shown as 6m144 (60+12 doubled). This value provides a means to track the efficient use of small gears and, far more important, directly relates to the cost of materials and therefore the value of a gearbox in an exchange.

Do please note that most gearboxes actually cost way more than the optimal design minimum, but that's how you learn to design gearboxes :-Þ

Constraints

Just as a reminder, the design constraints are:

• 15 Shafts maximum
• 30 Gears maximum, including the free spacers
• Gears and spacers can be stacked to 3 levels, including spacers

• 12 sum 7/5 6/6 5/7 is a Knight's move, one diagonal plus one adjacent
• 11 sum 7/4 6/5 5/6 4/7 is a double adjacent
• 08 sum 5/3 4/4 3/5 is a single diagonal
• 06 sum 3/3 is a single adjacent
• Spacers may be diagonal to a 6 gear or smaller
• Spacers may be adjacent to a 4 gear or smaller

• / implies "meshes with"
• * implies "shares a shaft with"

Sequences such as 3/5 * 5/6 can use a single 5 gear (the 5 gears "share a shaft") if you can get the input and output on the same level. If you are running out of shafts, which is usually the case with a 3-output gear box, a 6/6 combination will often allow you to eliminate two or three transfer shafts.

Target Cost

I rarely use a large gear or an expensive gearbox ratio. Tamutnefret's cheap Gearbox Ratios will suffice most of the time.

• Start out with the cheapest gear box ratio that satisfies your requirements.
• Count the large and medium gears in the gear train that has the most ratios.
• Add any ratios in the other gear trains that aren't already on the list (including additional instances)

If you have a 3/5 * 5/6 sequence that might collapse into a 3/5/6 sequence, don't get too excited about it. You may need to reverse the sequence to 5/6 * 3/5 in order to drive a second or third output, or you may need to use an extra 6 gear to reduce the number of shafts that are required. Just tally up the 5 + 6 + 7 factors and call that your design objective.

Small gear requirements are all over the place, depending on the distance between the outputs and the differential speeds. Other than the elimination of backtracking, there's not much that you can do to minimize the number of small gears.

Rules of Thumb

• Work with factored numbers. Track 3/5/6 or (3/5*5/6) as (3*5)/(5*6), rather than collapsing it as 50%.
• The order of the numerator and denominator items doesn't matter. You won't have that many choices, but you can freely rearrange the factors.
• Work from the top down. Satisfy the unique ratios first, then combine the common ratios.
• When you're linking gears, working top down, try to put the output on the 2nd level, the bridge on the 3rd level, and the input on the 1st level. This reduces the number of spacers that you'll need for your chains back to 1A.
• Try very hard to keep your smallest gears on the bottom of the stack. Medium and large gears make lousy neighborss
• The algebra works if you multiply by 100 and drop the fractional part of the percentage.
• Do everything you can to avoid adjacent size 3 small gears. The shaft count will kill you.
• Adding couple of small transfer gears on the output row of a required 1-output or 2-output gearbox is a very cheap way to double or triple your chances of reusing or exchanging the gearbox.

Optimum 3-Output Gearbox Designs

All of the designs on the design lists have been verified on a Gearbox Assembly Table. The list includes only one optimum design for the various unique 3-output combinations, where optimum is defined as the verified design that uses the fewest units of metal. This means that nobody, as yet, has found a way to make a cheaper gearbox for that particular 3-output combination. If you have a verified design for other combinations, or a less costly design for a documented gearbox, do please add your design to the library.

Sunset Venery has analyzed most of the gearboxes that are available for trade per the Gearboxes Trade List so you can get a good feel for values and can pick up a lot of design ideas by examining the following examples. If it all looks like just too much trouble, you can use the Gearboxes page to find potential traders, with a reasonable expectation of making a fair exchange.

The 3-output gearboxes on the design pages are listed in alphabetic order. Using Ctrl+F find a target output ratio is a effective way to find an appropriate design for a 1 or 2 output gearbox, as you might be able to use just the second or third outputs. Direct use of the wiki search function is also an excellent approach.

• AB Plus contains the first half of the designs.
• Except AB contains the rest of the designs.

Do please leave templates as the first and last entries in the list, so that people will be able to easily copy a template and plug it in at the proper alphabetic location. Please don't add additional bold or italic formatting, as that distorts the edit mode table. Pressing your "insert" key, and using overwrite mode, makes the editing mode far more stable.

_	_A_	_B_	_C_	_D_	_E_	_F_	_G_	_H_	_Used_	Range	Gear Train
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8
7
6									Count	Type	Comments
5										Small
4										Medium
3										Large
2										Cost
1										Design	Template