Dremel Tool

[jbrock27]

@ Jim, Yes, they are under those blue caps on either side. Some models have the brushes in the horizontal, some in the vertical. Some caps are gray or black. Lot's on youtube about brush replacement.

Thanks James.  I have no issue with mine currently but when I saw RAM mention getting to the brushes, it got me to think maybe it is is good idea to put some 3 In 1 Electric Motor Oil on them from time to time for maintenance sake.

If you're buying the Dremel/moto-tool for strictly hobby use, save your money and buy a pair of Xuron rail cutters instead.
Whatever you use to cut your track, cuts will need a light dressing with a needle file anyway.
The Dremel is much better utilized for sharpening lawnmower blades.
When I'm using small drill bits, or taps, I prefer a pin vise instead.

I use the Dremel for frame and shell remodeling as well as other, non cutting track related hobby uses.  I do think it is a good tool to have for the hobby of model trains.  There are plenty of times when I use the Xurons that I don't have to dress the rails any further.  When I do, it is not the tops I file, always the edges.  I find a large file or grinding wheel best for sharpening lawnmower or lawn tractor blades  I agree, pin vises are the way to go when using small bits or taps.

[Len]

DO NOT put oil on motor brushes, they are made of graphite and self lubricating. Getting oil on them creates a major mess, and doesn't help performance at all.

3-in-1 Electric Motor Oil is intended to be used on the shaft bearings of larger electric motors, not the brushes.

Len

[jbrock27]

Thank you Len, for the heads up.

How about using Conducta Lube?

[Len]

You should not use any lubricating product directly on motor brushes. It mixes with the graphite powder residue from the brushes and causes all kinds of problems. One of the main ones being clogging the slots between commutator segments, shorting them together.

Len

[jbrock27]

Thanks again Len.

Would you also apply that philosophy against putting Conducta Lube on HO motor brushes?

[Len]

Yes. Motor brushes are made from graphite, so they are self lubricating. There is no need to add a lubricant to them. On motors with removable brushes what is needed is to clean out the slots between commutator segments once a year or so. This can be done using the tip of a 'heavy duty' tooth pick. On an open frame motor, where the commutator segments are more accessable, polishing them with an erasor is also a good idea.

Len

[jbrock27]

On motors with removable brushes...clean out the slots between commutator segments...This can be done using the tip of a 'heavy duty' tooth pick...an open frame motor, where the commutator segments are more accessable, polishing them with an erasor is also a good idea.

Len

Hmmmmm.  I have done the above many times, using the tip of a #11 Xacto blade to clean the slots in the coummutator and a soft track cleaning block, made by Perfect to polish the commutator and have still found times that adding a little Conducta Lube to the brushes and commutator improves both noise and slow speed performance. 

Isn't Conducta Lube sold with part of that purpose in mind

[Len]

It may give a short term improvement, while the commutator slots are clear, but long term it causes more harm than good.

The reason for the slots in the commutator is to provide electrical isolation between each segment. Over time, graphite residue builds up in the slots, providing an electrical path between segments, and you start to lose motor power and efficiency. Worse, the motor starts to run hot, degrading the motor winding insulation over time.

Adding a lubricant to the brushes speeds up the process of filling in the slots. And using a conductive lubricant means the slots don't need to be as full of graphite residue before the electrical isolation between commutator segments is degraded.

I've seen too many motors with burned out armature windings, where a lubricant was applied to the motor brushes, to recommend it to anyone.

Len

[jbrock27]

...but long term it causes more harm than good.

Len

By that, do you mean constantly adding Conducta Lube?

Adding a lubricant to the brushes speeds up the process of filling in the slots. And using a conductive lubricant means the slots don't need to be as full of graphite residue before the electrical isolation between commutator segments is degraded.

Len

Let's be clear here so we know we are on the same page; there is a difference between the effects of a "lubricant" as you put it, such as the oil used to lube a drive shaft or bearing and Conducta Lube, being placed on the brushes and commutator.  I know that you know, that regular "lubricant" is not meant for HO motor brushes or commutators and I also, would never make the recommendation it be used there.  Conducata Lube, however is different than those lubricants.

Question: over time, won't the slots get filled in anyway, requiring cleaning regardless of adding Conducta Lube or not?

[Len]

The places I would use Conducta Lube are wheel wipers, axle wipers, and tender pins/loco drawbars that are part of the electric pickup, and maybe a drop on rail joiners before installation if they're not going to be soldered. Basically anywhere there is metal-to-metal contact that is part of an electrical path. It also makes a decent motor shaft bearing lubricant.

While some slot car, which is where I think this idea originated, enthusiasts use conductive lubricants on motor brushes, it's a totally different enviroment than model railroading. They do it primarily to reduce motor arcing at the extremely high RPM range slot cars operate at. And even then, it only lasts until the end of the brush gets worn off, often before the end of a race at the RPM's they operate at. In many cases slot car motors get cleaned, and the brushes replaced, after every race.

So for general use in model railroading I don't recommend putting Conduca Lube, or any other lubricant, directly on the motor brushes. YMMV, if so it's one of those things will have to agree to disagree on.

Len

[jbrock27]

...it's one of those things will have to agree to disagree on.
Len

I guess we will.

YMMV
Len

And I guess it does.

Case in point, I recently bought a new, in the box Bachmann S4 (posted about it here).  Took it out and ran it and it made some less than normal noise.  Rather than ship it off to be "repaired" I opened her up to see if I could solve it myself and looked for something rubbing somewhere or broken or out a place and could find nothing.  Figuring it might have been sitting in it's box for a while, I gave it some oil lube on the metal drive shaft near where it meets the motor housing, put some grease on the worms; still the same result.  The noise was like something was rubbing somewhere.  So, having explored every other option and possibility I put a drop of Conducta Lube in the slit in the plastic motor housing where the brushes would seem to be and guess what happened next?  Quiet and as smooth running as anything else I have.  The noise disappeared.  So that is my story and experience, among other positive ones.

Is it possible that what you had been seeing with burnt out armature windings was really the results of lack of locomotive maintenance or abuse, by their owners?  Or applying the wrong kind of product in the wrong places?  Or may I suggest that if those folks knew enough about what they were doing in the first place, they would not have likely had a reason to come see you at your repair shop?

[Len]

Many of my customers brought their equipment to me because they didn't know what they were doing, knew they didn't, so brought it to me to service so as not to damage it.

The only time I'd see 'smoked' armature windings where oil on the brushes wasn't present involved frozen, or really gummed up, drive trains the owner tried to overcome by pushing the throttle all the way up. If the drive train was free turning, invariably I'd find oil on the brushes.

Like I said, this is one where we'll have to agree to disagree, so I don't see any point to continue going back and forth about it.

Len

[Bucksco]

I am looking to purchase a new Dremel tool and kit and was wondering what people are using now for HO? Better to go with corded or battery and what attachments that I should make sure I have. My old cord model has died.

Just a reminder of what this thread is about....

[jbrock27]

Thanks for the reminder Yardmaster.  Please see that I am aware of that, as I, have posted several times about the original Topic.  I am more than glad to discuss the topic of Dremel tools further.

...I don't see any point to continue going back and forth about it.

Len

Thank you for your responses Len and confirmation regarding your former clientele.  I am just offering different points and perspective that you may not have considered or neglected to mention.  I don't know why there would be an imposed "limit" to the amount of discussion on a topic.  No one forces you to respond.

[jlc41]

Hi Penn1974, I need a pair of rail cutting pliers. Which one would you recommend, their are so many to chose from. Thanks