What is tooling? - KSP-RO/RP-1 GitHub Wiki

Tooling are the parts that make your parts.

Unlike stock parts, procedural parts can come in many shapes and sizes. In RP-1, "tooling" represents the cost of researching and building the machinery to build that part cheaply. Normal parts have unlock costs. Tooling is basically the unlock cost for procedural parts.

Tooling your parts can save you a lot of money, but more importantly, time. The cheaper your parts are, the faster they are produced. There is an RP-1 button in the VAB toolbar that will tell you what you have tooled already and the costs of tooling vs not tooling.

Producing tooling means you don't have to hand-carve this for each rocket.

How does tooling work?

• Tooling works in a range of 4%, so if you tool something at 1.00m you will have free tooling down to 0.960m and up to 1.04m.
• Tooling a new width (diameter) is much more expensive than tooling a new length; it is far easier to stretch a tank than it is to produce the machinery to manufacturing one with a completely different diameter.
• Re-tooling a diameter that you used in a previous tank tech level of the same family is discounted. If you tooled steel separate-structure tanks to a 2-meter diameter then 2-meter aluminum separate-structure tooling will be cheaper.
• Separate structure, integral structure, and balloon tanks require very different manufacturing processes. Tooling cannot be shared between the three families, but can be shared within them.

When should I tool?

• Because tooling costs are so cheap for early tanks, it's recommended to tool all parts on your early rockets so you speed up your build times--even if you only intend on using a part once or twice.
• Later you should not tool all of the parts; it should really only be used for sizes you plan on using again. Isogrid (see the image above) tooling is very expensive!
• Plan ahead with your rocket builds; try to use similar diameters in order to maximize tooling.
• Don't tool until you have tested your rocket design and determined that it is a good design you want to move forward with. It is a big waste of money if you don't.