Dear Robotshop Community.
I have the following motors:
The motors are mounted inside my robot with the shaft exposed on the outside of the chassis.
I’m not looking to drive this through water but if it’s raining outside will they survive?
My concern is the motor shaft & if water seeps in slightly could this damage them?
I appreciate any advice & look forward to your reply’s.
hi, I can advise you to waterproof the engine as best as possible. on the joints and on the holes you can put a sticker so the humidity cannot penetrate easily. Once the motor wires are welded, it would be a good thing to paint the contacts with a bit of nail polish from your mother. instead on the motor shaft where there is the joint put a bit of grease.
Waterproof the engine and place stickers on both the joints and holes so that humidity will not penetrate easily.
@Mus84 you can check out what this user did in the tutorial section:
https://community.robotshop.com/forum/t/waterproofing-a-dc-motor-with-sugru/13077
If water can find a way, it’ll cause the gears to rust. bmoscato’s suggestion is good.
The ideal way would be to use a shaft seal and O-ring.
This having been said, the Lynxmotion A4WD1 uses the same motor and that section is exposed. It’s used outdoors, and we have not heard of any issues with water infiltration, though we would certainly not suggest it be used in the rain or wet areas.
Thank you for your advice. Where can I find the seal shaft to put on the motor? If you could tell me what to look for I can order it and try it out. Thanks in advance
Could I use the propeller shaft grease and leave it at that? I’m not looking to submerge the whole motor but just protect the shaft from rain, wet grass
I agree with @cbenson with using a shaft seal and/or o-ring. I would probably go with something like this if I were developing a project that may get wet occasionally:
Thank you so much for showing me. Are these the exact sizes for the motor I have?
Also are these just placed on or do you need to install them in a specific way?
Thank you
Edited after looking at the original post.
Yes, your motor looks like the D shaft goes all the way to the housing… I’m not sure if the o-rings are a good fit for you. You may need to research other options.
@Mus84 what kind of frame are you running this in? Do you have enough room to have the motors sit further inside the body and use a coupler or some other device stick out to attach to the wheels?
Can something like this small fixture fit which contains a housing, ballbearing and o-ring?
https://www.ebay.com/itm/Motor-Shaft-Seal-Set-For-Shaft-4mm-Type-S-Version-2/272898156396?hash=item3f89ff676c:g:8JwAAOSwcu5UNRph
@Mus84 There’s a good chance the shaft grease might work, but also a chance it might not… so it’s all about managing risk.
I do not recommend o-rings, they do not have a hermetic seal and if they is hermtetic they are friction and over time they disintegrate anyway, I insist on regularly adding grease to the outside of the motor shaft so that the humidity cannot penetrate.
it is normal to have constant maintenance on outdoor vehicle.
Greetings from a qualified mechatronic.
Thank you for your expert advice on the subject. Would it be advisable to just spray the outside or inject grease via an open screw hole directly into the motor which will fill it up and hold the grease inside for a longer duration? Would that be harmful to the dc brushed motor?
I’ve ordered this:
I can recommend a graphite grease or the one in the link, but only for the outside, for the gearbox I do not know the specifications, if they are nylon or plastic it is better to grease them with a specific grease for nylon or plastic.
I have received some grease and applied it to one of the motors. The second motor I have left without any added protection. Both motors seem to be working fine submerged under water. I’m surprised and curious why both are working. One of the motors I have injected the grease directly into the front which filled up the front of the motor. I didn’t just apply it to the shaft.
of course they work, even if you put the battery together in the water it works … when the grease-free engine dries it will start to rust, it’s not an instant thing … for example: a petrol pump of a car is an electric motor and is completely immersed in gasoline. the fact is that alternating wet and dry creates a chemical reaction called rust. (shame about the two engines)
I hope your " fieled up" motor have metal gear inside because the greas is for metal and not for nylon gears , if they are nylon there is a good chance that they will corrode.
So it’s over time that problems occur😳 Good job I used my old motors! Does the water that’s trapped inside stay inside or slowly seeps out? How long until the motors begin to deteriorate due to rust?
you asked two very difficult questions to answer, depending on so many things. it depends on the quality of the engine, it depends on the frequency that it gets wet, it depends on the temperature of the environment and on the humidity in the air. however the first thing that oxidizes will be the electrical contacts that are made of copper
