Re: Wind hard or not so hard?
I tend to thinking of motors as being more analogous to half-lives than to
a light switch. I do not believe that a motor hits a point where it simply
transitions from being new to being broken in. I think that after the first
hardish wind, the motor may be halfway or two thirds of the way broken in.
Then successive winds serve to break it in further. I am basing my theory
on observing the change in the loop length after successive windings. The
loop elongates most after the first winding but continues to lengthen to a
lesser degree with each subsequent winding.
I think this is why we historically have seen duration increase as the
number uses of a motor increases if nothing else changes.
Regards,
Nick Ray
On Mon, Nov 18, 2013 at 9:10 AM, <Warthodson_at_aol.com> wrote:
>
>
> If I am trying to wind a motor to as close to "max." as I can, without
> breaking it, I always wind to torque not turns.
> One other comment. If I wind a motor to "max." I have about a 50% chance
> of being able to wind it to "max." a second time without it breaking.
> Gary H
> -----Original Message-----
> From: Don Slusarczyk <don_at_slusarczyk.com>
> To: Indoor_Construction <Indoor_Construction_at_yahoogroups.com>
> Sent: Sun, Nov 17, 2013 11:18 pm
> Subject: Re: [Indoor_Construction] Wind hard or not so hard?
>
>
> So you guys wind only to a torque and do not care about actual turn
> count? I find that amazing. I am just the opposite, I go by turn count then
> back off to a torque level to regulate the height. So If I want say 1750
> launch turns on a motor that can take 2000 I may wind to1850 then back off
> some turns to get my desired launch torque. If the motor could take 2000
> turns, I would not wind to 2000 then back off 250 to 1750. I typically only
> wind (by turns) past my target minimum required launch turns then back off
> some to knock off some of the torque. Also any new motor I never fly use
> until broken in. I take a freshly made motor lube it up generously then say
> if it would take 2000 turns I wind it to ~1750 or so then unwind and
> measure the length to see if it stretched, a 14": loop would be like ~14.7"
> after a break in then I relube and then use that for my flights. Once I do
> that process and the motor takes a stretch set, the motor is rather
> consistent over the windings for the day if you done push it too hard. The
> only time it starts to deviate is if I really push the motor hard multiple
> times in a row. If I find my model is needing near max turns on each flight
> and I wind to near max turns on each flight and then say it hangs up, and
> then I wind max again and hang again, then do it again I find the motor
> will sag and drop off on these subsequent windings. So I then set that
> motor aside for a while or make up a new one. Sometimes the "sagging" model
> will do equal time from less height sometimes it does less time as the
> model will not climb as high. I noticed this on Nocal a lot as the rules
> require 3 of 3 flights so often in a contest you take all three in a row
> and if you are leaning on the motor the first flight, the second flight
> will be within a few seconds but the third flight will always not climb as
> high and will either so the same time or sometimes less so on the third
> flight I usually do not back off as much as I know this will happen. I can
> usually also tell it is sagging when I start to back off. A sagging motor
> will drop torque quickly with a few unwinds which is something it did not
> before. I may have needed 100 unwinds to get my torque but after 3 or 4
> full winds of the rubber only 50 backoff gets the same torque then I know
> the motor is toasted for the day.
>
> Don
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Received on Mon Nov 18 2013 - 06:27:41 CET
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:48 CET