Whilst on an opal selling trip to Taiwan, Harry visited a number of factories producing jewellery and was introduced to a new metal coating technique used by the local trade.
It had been found that ultra thin silver or gold foil could be perfectly coated onto copper, brass or other conductive surfaces by carefully spreading the foil over the surface to be coated and applying a positively charged current to the foil and a negatively charged current to the metallic or conductive surface to be coated.
The two surfaces were then brought into contact while a soft stream of air from a portable air compressor held them in place.
At this point, the foil was then zapped with 240 volts AC and then with 12 volts DC, resulting in a hyperbaric charge bonding the two surfaces together at a molecular level.
Depending on the desired effect and durability of the surface intended, multiple layers could be applied in the same manner.
This technique would not work with a non-conductive straight glass surface, however experimentation with a 10” mirror which had a badly faded coating showed that the surface conductivity remaining on the mirror was sufficient for the system to work, resulting in a perfect silver coating.
When returned to its Dobsonian mount, the mirror worked well, producing flawless images.
However, appreciating potential durability problems with silver coatings in amateur use, Harry got the manufacturer of the foil to produce an experimental batch of aluminium foil, and when this was applied to another mirror the same result was achieved.
It was not possible to produce a silicon over-coated surface in this same manner - just straight aluminium at this stage. However, so thin is the coating that up to twenty coatings can be applied before any significant degradation of the optical figure becomes apparent. Accordingly, annual re-coating of a mirror for twenty years becomes a feasible option.
At this stage, it is only planned to produce micro-thin aluminium foil in twenty-inch width, as the small number of larger scopes out there would not make a worthwhile market.
Initially, the foil will be available in 10m rolls, and Harry estimates that mirrors up to twenty inches in diameter could be re-coated for as little as five dollars each.