Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: ankit_ipu_niec on March 14, 2009, 08:42:17 AM

Title: Help required in waterproofing of dc motor
Post by: ankit_ipu_niec on March 14, 2009, 08:42:17 AM
hey guys i m in urgent need of your help.

I am making a boat and need to waterproof my dc motor.
if any one know how to waterproof a dc motor please reply to this thread

Thanks in advance  :D
Title: Re: Help required in waterproofing of dc motor
Post by: Razor Concepts on March 14, 2009, 09:26:42 AM
DC motors can be run underwater (unless you're in salt water). If you are in salt water I would not reccomend submerging the motor itself, I would put a shaft on the motor that connects to the propeller outside of the boats hull.
Title: Re: Help required in waterproofing of dc motor
Post by: ankit_ipu_niec on March 14, 2009, 09:35:50 AM
thanks Razor for ur immediate response

can you please give me a detailed description of waterproofing in case of salt water is used
Title: Re: Help required in waterproofing of dc motor
Post by: Trumpkin on March 14, 2009, 07:55:13 PM
How big is this boat? You could also try a stuffing box http://en.wikipedia.org/wiki/Stuffing_box (http://en.wikipedia.org/wiki/Stuffing_box)
Title: Re: Help required in waterproofing of dc motor
Post by: ankit_ipu_niec on March 14, 2009, 09:14:29 PM
first of all thanks for your reply.

my robotic boat dimension is 25*15*10 cm(cube).








Title: Re: Help required in waterproofing of dc motor
Post by: MaltiK on March 17, 2009, 01:19:04 PM
you can always wrap everything in plastic wrap or something, but it all depends on the actual liquid it is in, as razor said, as well as the depth you are going. If you are on the surface, pressure is very small or non existent, if very low, pressure is higher, and so water proofing is more difficult and expensive.
Title: Re: Help required in waterproofing of dc motor
Post by: ArcMan on March 17, 2009, 01:45:09 PM
Be careful about wrapping the motor in plastic.  It may not run cool enough.  Most motors depend on open air to remain cool unless they are specifically designed to be sealed.
Title: Re: Help required in waterproofing of dc motor
Post by: MaltiK on March 17, 2009, 03:51:16 PM
Be careful about wrapping the motor in plastic.  It may not run cool enough.  Most motors depend on open air to remain cool unless they are specifically designed to be sealed.


But isnt coolness and heat still transferred? Plastic isn't a good enough insulator.
Title: Re: Help required in waterproofing of dc motor
Post by: ArcMan on March 17, 2009, 08:37:24 PM
Heat is still transferred via conduction and radiation, but not convection.  Convection cooling is the primary cooling mechanism for an open-frame motor.  It needs air flow.
Title: Re: Help required in waterproofing of dc motor
Post by: Admin on March 26, 2009, 12:50:23 AM
http://www.google.com/search?q=waterproof+motor+tutorial (http://www.google.com/search?q=waterproof+motor+tutorial)

(remember to google before asking! ;))