Most letterpress machines, from Adanas to Wharfedales embody the technology of the first Industrial Revolution. They use a ‘total loss’ lubrication system, the thicker the oil the longer it stays where needed — they should stand on a drip-tray to catch waste oil. They need regular lubrication at every point where two parts rotate or slide across or through each other. Even a humble Adana has around thirty such points, the thirstiest of which have special oil-holes. Elsewhere, such as the ink-disc spindle, roller arms and bearings need just a carefully applied drop every thousand impressions or so. Little and often is best rather than risk an excess splashing or dripping onto the rollers or paper to spoil your work.
Sewing machine or cycle oils such as 3 in1 are far too thin to adequately cushion the bearing surfaces, especially those loosened by years or decades of wear. Buy a good pump-action oil-feeder can from a tool shop and use, preferably a ‘straight’ SAE 30 grade oil or the budget-price 20/50 or thicker engine oil sold by Halfords and some supermarkets. We don’t need the high performance additives in premium grade oils.
As a modern, ‘house-friendly’ alternative, those concerned about the messiness of conventional oil might try the synthetic lubricants, some of them Teflon-based, which are sold in tubes or aerosols for lubricating cycle chains and bearings. These are relatively dry to avoid attracting road dust and the white grease variety smeared onto accessible parts and forced into the oil-holes is a long-lasting, clean lubricant — quite splash-proof! Do, however, ensure such grease is forced well into any oil-holes.
Remember that, although many of us bought our presses cheaply enough, letterpress equipment is no longer in production. Even the last Adanas, assembled to order from remaining parts, each cost more than the price of a popular computer. Machines allowed to run dry will tear apart their working surfaces or even seize solid and,if you have to rely on professional help, such ‘arthritic’ cases can only be rectified by craftsmen whose charges reflect their skills.