Geo wrote in message
...
On Thu, 26 Feb 2009 11:13:47 -0000, "N_Cook" wrote:

Does anyone know of a source of data for the traverse spacing, turns per
mm
or mil, for the smallest wire gauges of say 45 to 50 SWG or 40 to 45 AWG.

If wire is 0.05 mm thick, say, then the traverse should lay down at
something marginally wider than that. I appreciate it is dependent on
drawing die imperfections/ enamel thickness/ chaffing etc but at least a
starting value and then suck it and see with a trial run or 2 with the
actual wire. Or a formula for the general case.

I am not sure if an allowance was made?
Looking at the table for travers on the Avo Douglas machine on page 21 of
this
pdf:-
http://www.g1jbg.co.uk/pdf/avowave.pdf
Taking, for example, a 10 thou traverse, the table gives gears of 30,40
and
48,36 which fit precisely into the formula at the bottom of the table for
10
thou wire diameter. Similarly for 20 thou wire diameter.

--
Geo

I will go with that Avo/Douglas data, going on the conservative side
50 swg 20 percent
46 swg 8%
38 swg 6.5 %
30 swg 5%
25 swg , 4%

Incidently I think the ETA reversing mechanism may be better than the
Douglas one, for fine wire anyway. I seem to remember that if everything was
not just perfect then sometimes with the Douglas there would be too much of
a kick on the traverse arm and so break the wire, at reversal. I discovered
that the kick I was getting on my ETA one (in the right sense of slackening
rather than stretching, in both directions of traverse) was just due to a
slack end bearing of the leadscrew. The ETA uses a rubber rimmed cam that
engages with a flywheel to flip a synchronised? dogclutch across to engage ,
meshed I think, cleanly with the reverse set of cogs.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/