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Startrek
23-02-2022, 02:00 PM
Without doing the arithmetic does anyone have the worm cycle period for the EQ8-R pro mount
I read somewhere on CN that it’s 198 sec , seems very short as my EQ6-R pro is 480 sec
Any advice appreciated
Thanks

xelasnave
23-02-2022, 02:11 PM
I must say I dont know but as a knee jerk responce 480 seconds sounds long so I will follow the replies with interest...I am surprised I dont know for either considering I own both
Alex

Startrek
23-02-2022, 06:00 PM
I just received an email from a reliable source as follows -


Worm Cycle Periods

Earth Sidereal Day = 86,164.1 sec

Worm Cycle Period
Sidereal Day (sec) divided by number of main worm drive ring teeth

HEQ5
86,164.1 / 150 = 574 sec or 9.6 min

EQ6-R
86,164.1 / 180 = 479 sec or 8min

EQ8-R
86,164.1 / 435 = 198 sec or 3.3min

NB: The above worm period cycles do not factor in any periodic error or inefficient worm gear meshing

Martin

xelasnave
23-02-2022, 06:28 PM
That is interesting I would have thought it is the other way about... but that is the folly of guessing.
I have yet to use mine and starting to wonder if I ever will...more rain today...might have to set up a traveling rig and go somewhere but where?
Alex

Startrek
23-02-2022, 06:46 PM
Alex
Yeh I was surprised by the worm cycles of each mount too
It’s raining on the South Coast what’s new
North Coast apparently copped a dumping
Forget February and fingers crossed for March
La Niña is suppose to back off in March with weather expected to normalise in April

OzEclipse
23-02-2022, 07:26 PM
The worm period is the number of minutes in a sidereal day (23h56m4s or 1436.075mins) divided by the number of teeth.

The bigger the worm, the more teeth, the shorter the period.

Let's use 1440 mins (24 hrs) as a round number.

No Worm..............Period
..Teeth.................(mins)
100......................14.36
144......................9.97
180......................7.98
359......................4.00
435......................3.30
500......................2.87

Startrek
23-02-2022, 08:11 PM
Thanks Joe for the advice

Makes sense when you physically compare the size differences between the 3 mounts

Works out similar as 86,164.1 sec sidereal day divided by 60 is 1436.4 mins

Martin