In article ,
JoeJoe wrote:
What is the difference between a primer and an undercoat?

The primer is to give good adhesion to the material. Hence different ones
for wood and metal, etc. Undercoat at one time was always near the same
colour as the top coat but less expensive, so made the job slightly
cheaper than using two or more coats of top to get the depth of colour.
But things are a bit blurred these days. ;-)

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*INDECISION is the key to FLEXIBILITY *

Dave Plowman London SW
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