And when can I pick this up?
By Michael Chumbler
The rules for inventing 1889 are very thorough on how to research and what skills are necessary to build individual devices. However, when it comes to how long it takes to build your creation the rules are sorely lacking. The following addition will fill that critical gap.
There are two parts to creating an invention, the design time and the actual construction time. First, the inventor must develop a working design. The basic rule for how long a device takes to design is complexity of the device in days times reliability. PC’s with an Intellect of 5 multiply design time by .75; PC’s with an Intellect of 6 multiply design time by .5. If inventor’s understanding exceeds complexity of the device by ten divide the design by two. If understanding exceeds by twenty, divide by four, etc. If the PC is increasing the reliability of an already invented device, design time is still complexity in days times reliability of the improved device, however, subtract the original design time.
In devices of complexity of 10 or less, the design time includes the build time. Since in most cases these devices are existing designs and the PC is merely making their own version of an existing idea.
Once our intrepid inventor has a working plan, he now needs to build his masterpiece. Build time is complexity in days divided by reliability. The idea behind this concept is a more reliable design is easier to build as it is less complex and uses more readily available materials. After the prototype is completed, divide build time by 2 for all subsequent devices. Minimum build time is one day.
Inventor INT 4, Area Understanding 31, Device Complexity 20.
The time to design will be based on the standard success rule to invent and the resulting reliability. Figure device experimental success number is 2 and the die roll is 5 for a reliability of 3. Design time is complexity in days times reliability, thus in this case 20 times 3 or 60 days. Divided by 2 because inventor’s understanding exceeds device’s complexity by 10 for a total design time of 30 days. Build time will be 30 days divided by the reliability of 3 for build time of 10 days. Once the prototype is completed all additional devices will take 5 days to build. If the same inventor later increases his devices reliability to 5 design time is 20 x 5 = 100 ÷ 2 = 50 – 30 days of the original design for a total of 20 days for the redesign. Build time is now 20 ÷ 5 = 4 for the first device with this new design. Divide build time by 2 for all other devices for a production build time of 2 days.
Inventor INT 5, Area Understanding 40, Device Complexity 36.
The time to design is with a reliability of 1 (experimental success number 4, roll 5). Complexity 36 x 1 = 36 x .75 (for intellect 5) = 27. 27 ÷ 1 = 27 for a build time of 27 days for prototype. Production time is 14 days. Inventor refines design (experimental success number 4, roll 5 + 1 for previous success = reliability of 2). 36 x 2 = 72 x .75 = 54 – 27 (for original design) = 27. Build time for prototype is 14 days production time is 7 days.
Inventor INT 6, Area Understanding 30, Device Complexity is 5.
Time to design is (experimental success number –1, roll 4) with a reliability of 5.
5 x 5 = 25 x .5 = 13 ÷ 4 (because inventors exceeds device complexity by 20) = 3 for design and build time of prototype. All production devices will take 2 days.
Additional option for diabolical GMs is for the PC to have to roll in secret. PC will have to roll difficult intellect to know if roll failed. If the intellect roll fails PC assumes his design is a success at reliability 1. After completing the design time the PC can roll intellect again. A moderate roll will reveal flawed design. If this roll fails, PC has one last roll at the halfway point of construction. An easy intellect roll will reveal the flawed design. This is the PCs final chance, if this roll fails he presses forward with his defective brainchild.