The engine was completed fifteen years ago, the builder already having produced a 1 inch scale "Minnie", followed by a 3 1/2 inch gauge LMS Jinty before tackling the Allchin.
Unsteamed from new, the engine is complete barring a pressure gauge. Motionwork turns over freely, the motion runs on air with various leaks from fittings and valve chest joint.
| scale | 1 1/2 inch & smaller |
| length/inches | 27 |
| width/inches | 12 |
| height/inches | 18 |
| weight/kg | 30 |
| cylinder material | cast iron |
| valve type | slide |
| valve gear | Stephensons |
| reverser type | pole |
| governor type | Pickering |
| lubricator type | mechanical |
| injector(s) | 1 |
| CE mark | n/a - non-commercial |
| working pressure/psi | 90 |
| boiler type | locomotive |
| boiler material | copper |
| safety valve(s) | 2 |
| safety valve type | Ramsbottom |
| mechanical pump | 1 |
| road speed(s) | 2 |
| differential | yes |