If you hold the board with its front side directed to you, it is better to remove the parts by pulling them. In this case, if a burr is pulled together with a part, it will make a pit in the board, not in the part. The best solution is to incise the hangers with a knife;
If you have difficulties in inserting a toothpick in the assembled gearwheel, rub the toothpick with a candle;
You may also lubricate all the projecting axes of the gearwheels before installing them on the frame. In this case the friction during rotation will be minimal;
However, do not lubricate the parts of pendulum connection with a candle – two projecting sticks in the tractor or timer. In this case the pendulum will not swing but skid;
Try to remove big burrs on the gearwheels, if any. The motion of some models is very delicate, and they may hinder it;
If any gearwheel creaks or squeaks, lubricate it with a regular candle, paraffin or wax. If the plywood edge is too resinous and some teeth tend to seize, which happens quite rarely, lubricate the gearwheel in the same manner;