On Sat, 20 Oct 2007 15:38:17 -0700, Andy Dingley
wrote:

On 19 Oct, 20:34, "R.H." wrote:
Most of them have been answered correctly this week, several links and a
couple of updates from previous sets have been posted on the answer page:

http://pzphotosans202xt.blogspot.com/

I still don't think that 1117 is a valve lapper, as the action is
wrong. The action of 1120 is to move CW, then CCW, in a manner that's
constant speed (albeit reversing). 1117 is different - the action is
to remain stationary, then flick quickly from one position to another.
That's not a good grinding action.


No, that is the way the old valve lappers, the ones with the crank on
the side and a suction cup to hold the valve head worked - back and
forth.


Bruce-in-Bangkok
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