A character can make a mechanical device if he/she makes a dice roll using his/her Engineering (including relevant specialisms) + CO.
The dice roll result determines the quality of the object, as follows:
| Dice roll result | Meaning |
| 3 or lower | Abysmally made - device falls apart before completion or does not work |
| 3 1/2 - 6 | Poorly made - the device looks worse, is more likely to break and works less well than a normal item |
| 6 1/2 - 10 | Competently made - the device is normal quality |
| 10 1/2 - 15 | Well made - the device looks better, is less likely to break and works better than a normal item |
| 15 1/2 or more | Excellently made - the device looks very good, is unlikely to break and works very well |
There is a modifier to the dice roll for the type of mechanical device being made, and the quality of the design; the time and cost of materials are also determined by these factors, as follows:
| Device type | Basic time to make | Basic cost to make (materials) | Modifer to making dice roll |
| Lock | 3 hours | 1s | +2 |
| Safe | 1 week | 10s | -2 |
| Trap | 12 hours | 5s | +0 |
| Design quality | Time multiplier | Material cost multiplier | Modifier to making dice roll |
| Abysmal | x 80% | x 80% | +2 |
| Poor | x 90% | x 90% | +1 |
| Competent | x 100% | x 100% | +0 |
| Good | x 110% | x 110% | -2 |
| Excellent | x 120% | x 120% | -4 |
If a character tries to make mechanical devices without the right tools, he/she receives a penalty of at least -3 (referee's discretion) on the dice roll.
Normally, a character will be working off a pre-prepared design. If he/she needs to create an ad-hoc design for a mechanical device, the quality of the design depends on the result of a dice roll using his/her Engineering (including relevant specialisms) + IQ, as follows:
| Dice roll result | Meaning |
| 3 or lower | Abysmal design - devices made this way are likely to fall apart or not work |
| 3 1/2 - 6 | Poor design - there are significant design faults - devices built this way are likely to look worse, to break and to work less well than a normal device |
| 6 1/2 - 10 | Competent design - there are only minor design faults and so devices are likely to work normally |
| 10 1/2 - 15 | Good design - devices built to this design are likely to look better, less likely to break and more likely to work better than a normal device |
| 15 1/2 or more | Excellent design - devices built to this design are likely to look very good, unlikely to break and likely to work very well |