Degreaser for brushed DC motor

Discussion in 'General Electronics Chat' started by jamus, Jul 17, 2014.

  1. jamus

    Thread Starter Member

    Feb 11, 2013
    53
    0
    Does anyone know of a good degreaser that won't damage the coating on the windings of an electric motor? I would prefer something I could pick up at a typical hardware store.
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,515
    2,369
    WD-40. - Contact Cleaner - de- natured alcohol. for a few.
    Max.
     
  3. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
    5,680
    900
    The enamel used on the motor windings is pretty much impervious to any solvent you are likely to find in a typical hardware store. However, the plastics used in the construction may not be. I would recommend VM&P naphtha or Stoddard Solvent. VM&P naphtha should translate across our borders. Stoddard solvent is similar with a higher boiling point.

    John
     
  4. wayneh

    Expert

    Sep 9, 2010
    12,100
    3,034
    It may sound crazy, but I just cleaned up my miter saw rotor using plain old soapy water and an old toothbrush. Blotted it dry, let it sit in the sun a few minutes to thoroughly dry, done. Now, it wasn't really "greasy" to start with, just normal dust from wear of the brushes.
     
  5. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    Windings are lacquered in shellac on older motors and polyurethanes on newer motors. Don't use alcohol, or mineral solvents like turpentine or thinners or anything that says "spirits".

    Hot soapy water is good, and kerosine type solvents like WD40 or auto degreaser should be ok. Some auto degreasers these days use detergents and not solvents, they should also be fine.
     
  6. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
    5,680
    900
    Underlined comments are confusing. Turpentine is not a mineral solvent. It is made from wood (http://en.wikipedia.org/wiki/Turpentine). Apparently, according to the Wikipedia article, "mineral turpentine" is a term used in some locals for mineral-solvent based thinners. The mineral solvents I mentioned are largely aliphatic hydrocarbons (Stoddard has a up to 25% aromatic hydrocarbons, http://en.wikipedia.org/wiki/Stoddard_solvent) which have good grease cutting capability and poor solvent strength, even for shellac. The term "spirit" generally means the solvent was easily distilled and would have a lower boiling point than something like kerosene..

    Turpentine has slightly greater solvent strength than the hydrocarbons I mentioned, but its solvent strength compared to alcohol (ethanol) is considerably less. Turpentine cannot be used as a solvent for shellac, whereas alcohol is used for that.

    WD40 is mostly a petroleum (mineral) solvent very similar to the solvents I mentioned (VM&P naptha and Stoddard). It has a few additives to support its anti-rust claims plus a nice fragrance. Kerosene is of very similar solvent strength, but lower volatility. It contains up to C16 hydrocarbons (cetane). It is hard to see how one can recommend WD40 and kerosene, yet claim mineral solvents are bad.

    As for automotive "degreasers," that is a very broad and poorly defined term. Today, the "green" versions are likely to be water based and contain sodium metasilicate and similar caustic materials. Commercial carwash degreasers are particularly caustic. Both need to be thoroughly rinsed with water. Other modern degreasers may contain glycols and their monoalkyl ethers. Glycols and their monoethers are excellent solvents, and like other alcohols, will affect shellac. Butyl cellosolve (http://en.wikipedia.org/wiki/Butyl_Cellosolve) is one member of that class. It can be used in water at quite low concentrations to soften and remove acrylic floor finishes and some paints. I would not recommend an "automotive degreaser," unless I knew what was in it.

    In the days before green, we used Stoddard plus a little liquid dish detergent to clean engines and aircraft undercarriages. After spraying with that, we rinsed with water. It was quite effective. However, for an electric motor, I feel a simple mineral solvent like I mentioned above that will evaporate readily would be sufficient.

    John
     
  7. alfacliff

    Well-Known Member

    Dec 13, 2013
    2,449
    428
    the use of water based cleaning on older motors is discouraged, unless you let them dry for a long time or with heat, the coating cracks with repeatede heating/cooling cycles, and can lead to problems if not dried thouroughly.
     
  8. wayneh

    Expert

    Sep 9, 2010
    12,100
    3,034
    Coating? Do you mean the wire coating, if it's exposed to liquid water while under use?
     
  9. alfacliff

    Well-Known Member

    Dec 13, 2013
    2,449
    428
    no, while degresing aas it says in several replys above.
     
  10. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,515
    2,369
    One area to clean on a DC motor when you have it stripped down is the brush gear/holders etc.
    Over time the carbon dust accumulates, and especially on high voltage motors can cause tracking to ground on the brush holders.
    This should be cleaned with spirits that leaves no residue such as electronic aerosol degreaser etc.
    Or automotive paint prep degreaser spirits.
    Max.
     
  11. jamus

    Thread Starter Member

    Feb 11, 2013
    53
    0
    Ok, I will probably get some naphtha then. A gasket went bad on the gearbox, so the whole rotor and commutator is covered with grease. Lots of grease to clean off.
     
  12. bwilliams60

    Active Member

    Nov 18, 2012
    722
    88
    As a rebuilder of automotive starters and alternators, we used to use a citrus based cleaner that was very effective. It smelled nice, non toxic and if you washed it off with hot water, dried very quickly. Dish soap will work well also. Stay away from chemical degreasers. For other parts such as end plates, frames, brushholders etc, brake cleaner works really well. You can buy water based stuff but you have to experiment to find the good stuff
     
  13. tcmtech

    Well-Known Member

    Nov 4, 2013
    2,034
    1,639
    Always been rather fond of washing the grime out of my electric motors with gasoline and giving them a good blow dry afterwards.

    But that's just me. :p
     
  14. GopherT

    AAC Fanatic!

    Nov 23, 2012
    6,006
    3,763
    Brake cleaner is amazing. Not the wimpy green cans, but the good old fashion TCE - trichloroethylene. Side benefit of high chlorine-hydrocarbons = non-flammable.
     
  15. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    But turps will hurt polyurethane lacquer if the motor has more modern lacquer. And it's not nice to paint. :)

    Kerosene should be fine for both lacquer types.

    Thanks for the other info.
     
  16. NFA Fabrication

    Member

    Aug 12, 2012
    104
    3
    There is a spray made specifically for this. The easiest way to get it (That I know of), is to buy this style spray for RC car motors. It is getting a little harder to find, as most hobby grade RC is going towards brushless motors, but this stuff works amazing: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXSEL1&P=ML

    You may find it at a local hobby shop.
     
Loading...