On Fri, 20 May 2005 16:30:52 +0000, Brian Whatcott wrote:
On Thu, 19 May 2005 21:39:25 GMT, Rich Grise
wrote:
On Thu, 19 May 2005 19:20:48 +0100, Peter wrote:

Someone has lost the red "disconnect" button onmy KFC225 autopilot.

Honeywell want a lot of money for a whole new switch. Would anyone
know who makes this switch? It looks like a standard pushbutton
switch, with a button about 9mm diameter.

I could make a new button easily enough if I knew the thread used in
the centre of the button (the button has a male screw on it). It
certainly isn't metric.

If you _know_ it's not metric, it's probably 4-40 or 6-32. These are
standard thread sizes in that size of stuff. I've seen those buttons
before, so I'm pretty confident about that. Are you in a metric-only
country?

The switch manufacturer is probably one of the well known names...

Any info would be much appreciated.

One of these links might have some useful info:
http://www.google.com/search?q=pushbutton+switch

Hmmm....I must be out of sorts.
A person needs a button with a male thread.
He could make it himself if he knew the size.
The makers price is too high.
He wants someone like Rich to tell him the thread size.
Have I got the facts right so far?

So the hardware store has some screws at 5 cents each
or so for him to try. Let's say he might buy 5 different sizes.
That's a quarter. Is that getting too costly, already?

No, it's just that in the UK, inch parts (apparently) are kind
of few and far between. Didn't they used to refer to them as
"English" vs metric? Ironic, ain't it? :-)

The existing shaft on the switch has a male threaded stud. The
button (or knob) needs a female thread. But I'd think that even
in UK, there's _somebody_ _somewhere_ who has a 4-40 nut or a
6-32 nut on hand, just to check. As Peter said, if he knows
the thread size, he can make a button.
According to http://www.csgnetwork.com/screwinfo.html ,
A #4 screw is about .112" OD, which is mumble-mumble millimeters -
whaddaya, multiply by 25.4? And #6 is .138". The -40 or -32 is
just number of threads per inch, which divided by 25.4 is number
of threads per millimeter. With a magnifier and decent scale,
it's trivially easy to measure them. He could theoretically
even get the right sized tap, and just drill and tap a piece
of plastic. What would international mail be on a 2-ounce,
$3.00 tap?

For that matter, he could make a little form, add some mold
release, and pour some epoxy into it and make a knob in place.

Cheers!
Rich