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Ceremonial Torches need heat-resistant finish with appearance of Gold

August 19, 2011

Hi. I'm currently Engineering a non-commercial Ceremonial Torch (gas powered natural flame) in the UK, that requires a finish as close to Gold as possible (Colour and Gloss). Local area around the flame is seeing 400 degrees C.

Several thousand Torches will be manufactured.

Torch body is aluminium (approx. 800 mm high) - welded sheet and cast parts

Would prefer not to polish the aluminium body, if possible, prior to adding finish so a paint type solution is preferable, although polishing is not out of the question.

Have considered:
Gold Plate - flaked off under heat stress
Ceramic coating (paint) - excellent performance, haven't yet achieved a suitable colour and gloss match
Anodised - different colour shades across welds and cast areas
PVD - still reviewing. Possibly too expensive and capacity issues (Size & cycle time)
Zinc passivate - not convinced quality of finish is up to level required
Powder coat - haven't found the required colour available in a heat resistant version

I would be really interested to hear of any other process I should be investigating or alternate views to the considerations above.

Thanks in advance,

Ian Raper
Product Designer - Essex, United Kingdom