Motors, bearings, snap rings

[JLO]

Hi to all my copter went in salt water "Ouch" I know, ..... all electronics gone MK, stuff, Radian, servos, QC motors etc (maybe Il open a new thread on the crash later dont want to think about that for now) ....all ready rebuilding, but something interesting with the motors, the copter went down in a surfing spot in central America where the sand is black/grey very very fine, after inspecting the motors I put them under fresh water tap for a few minutes I notice, of course as I try to turn the bell the grinding noise of sand, so what the hell, open one up separate the bell and lots of sand stuck to the magnets, I assume that the black sand been more volcanic has magnetic properties so it gets attracted to the magnets on the bell, any way it was hard to brush it of until I decided to use a scuba tank hi pressure.... woala after a few blows all the sand gone the bell the magnets look super clean now the rotor it did not have sand but I blew it any way I notice the windings look pretty shiny so decided to drive to Boca bearings its near me and a very helpful gentelman name Mike sold me 2 ceramic bearings $10 each he mention they are way better quality than the original ones so I replace them put the motor back together and on another copter tested the motor it work like if it was brand new and it sounded much quieter and smooth I ran it several times and the same.....
So has any one has true knowledge on motors and their survival under salt water is there more to it, of course I am hesitant to reuse them on the new re build I will use new ones but this ex salty ones run very nice
the most difficult part in taking them apart is the Snap ring on the bottom is very tiny and regular snap ring pliers are too big I had to manufacture one by grinding the tips so they fit
any suggestions on to where to buy the correct pliers and spare snap rings I understand that the size of the snap ring is 5/32, also ideal to find stainless snap rings

 

[Bartman]

what motors are they exactly? if they are a 4mm shaft motor then the snap ring will be sized correctly when you buy them for 4mm. 15/32 is almost one half inch, what do you have on the motors that is one half inch?

thanks,
bart

 

[JLO]

View attachment 7769Sorry Bart the snap ring is 5/32 I bought a box at harbor freight tools I wonder if I can find a better quality Snap rings Stainless
But what is your take on the motors working fine
the motors are Qc-3328
thanks

 

[JLO]

Ok yes the shaft is 4mm the grove is 3.8 the thickness of the original is 0.37

 

[Bartman]

the thickness is 0.37, is it mm? the snap rings i put in with my bearing press tools are 0.015" thick, same as the originals.

I probably would have soaked the motors in fresh water after disassembling them, let them dry, then reassembled. if there's still salt in there then I probably wouldn't continue using them.

 

[JLO]

I actually did soak them in fresh water then blew the hell of them with the very hi presure of a scuba tank, then spray them with a contact electrical cleaner change the bearings and they sim to work great is there more to it, the only thing I am worried is the snap ring I would like to put a new one with the right tool

 

[Bartman]

JLO, I use an awl to press the snap rings into place. I place it on the end of the shaft, hold one side in place with my left thumb nail, then press the other side into place with an awl. If there's any doubt that it's in place you can give it a little squeeze with a small needle nose pliers. it should float in the slot and not be impossible to move around.

bart

 

[iscorama]

what size/modelnumber boca bearings did you buy for qc3328? I would like to give them a try

 

[Bartman]

I've got a bearing press tool available in the classfieds area, FWIW.

 

[JLO]

Sorry Bart what is awl and fwiw

 

[Bartman]

Sorry Bart what is awl and fwiw

JLO,

an awl is a tool for scribing layout lines on metal or for punching holes though leather and stuff. FWIW stands for, for what it's worth, meaning, it isn't super important but it's worth mentioning.

bart

 

[JLO]

Hi the Bearing # for the QC-3328 motor is SMR694C-422 verify with Mike that its the right # the 422 could be a 922 measure your bearings mention that they are the same bearings he sold to Film It