Having spent an enjoyable day building my resin balance I couldn't
resist the temptation to add a high tech add on .
Unless you use the balance at eye level there is always a danger that
parallax will result in an incorrect measurement. I could have added
a mirror behind the level marker like is found on multimeters however
this would still mean that I would have to bend down every time I
wanted to measure resin.
What I have done is added an electronic detector that lights up an
LED when the balance is level. Now all I need to do is pour and wait
until the light comes on.
The construction is fairly simple. Ensure that the 'spike' you are
using for a level pointer protrudes past the vertical board you are
using as a reference. I used a 16" drill bit for my pointer!
Mount an infra red LED and an opto dectector so that the spike passes
between the two. I used a ULN3330Y as the detector as it includes a
regulator, amplifier and detector all in one 3 pin package. To
increase the sensitivity of the detector I glued a short length of
narrow tube over the front and then painted the whole thing black.
Wire the output of the detector to a conveniently mounted LED, adjust
until you are satisfied and voila, one electronic resin balance.
I have tested mine thoroughly and it has a resolution equivalent to
one NZ 10c coin (about the size of a 5p piece).
Now, how about an electronic pip pin detector? :-)
Tony
Europa #272
-----------------------------------------------
Sent from Tony Krzyzewski's roaming computer
somewhere on the planet earth.
Reply To tonyk@kaon.co.nz
Visit http://www.kaon.co.nz
-----------------------------------------------
|