Dear Bill,
A very interesting point and clever calculations. I was relieved to see that
my two 'Rules of thumb' yielded similar results as I had not done your
calculations.
I have now had a chance to examine some paint work that I had done recently.
Three coats of paint were applied and, using your figures, I guess these
would come to a thickness of about 0.2 millimetres or 200 micrometres. This
looks about right to me on the new paint work. I use the thickness of my
thumbnail as a handy (sic) measure of one millimetre and I guess the paint
would be about one fifth of that.
Cheers,
Pat Naughtin
CAMS - Certified Advanced Metrication Specialist
- United States Metric Association
ASM - Accredited Speaking Member
- National Speakers Association of Australia
Member, International Federation for Professional Speakers
--
on 2001/09/08 01.32, Barbara and/or Bill Hooper at [EMAIL PROTECTED]
wrote:
>
>> About 60 �dips� (of a paint roller) will
>> use one litre of paint and cover about 15 m2.
>> ...
>> In each hour you will use about 7 litres of
>> paint and cover a little over 100 m2.
>
> Interestingly, this information can be used to calculate the thickness of
> the paint on the wall. Using the relationship that volume (V) = area (A)
> times thickness (T) and the first set of data above (V = 1 L = 1000 cm^3 and
> A = 15 m^2 = 150 000 cm^2) one can calculate the thickness in centimetres
> to be about 6.7 times 10 to the -3 power or 0.067 mm.
>
> The second set of data yields exactly 0.07 mm for the thickness and is
> consistent with the first one one since all values are aproximate.
>
> That strikes me as a bit thin even for a coat of paint (it's less than a
> tenth of a millimetre). I really don't know anything about the practical
> aspects of painting. Is a thickness of less than 0.1 mm reasonable?
>
> Regards,
> Bill Hooper
>
> ============
> Keep It Simple!
> Make It Metric!
> ============
>
