Restarting an Unused HO Engine

On 8/17/2009 7:11 PM W. eWatson spake thus:

I was talking about the electrical connections between the trucks and the motor.

OK, now I've got an Athearn loco of the same vintage as yours in front of me. Here's the rundown of the electrical system:

The truck assemblies each have two metal plates that ride on the bronze wheel bearings, so each plate picks up current from a pair of wheels. In the stock configuration, the plates on one side of the looco have that tab that sticks up and contacts the contact strip above the motor; the other pair of plates is under the bolster (the pivot for the trucks) and rides against the bottom of the frame.

One side of the motor is connected to the contact strip; the other side contacts the frame via a spring contact.

So you can see how all these connections are simply metal rubbing against metal, with only the weight of the loco itself pressing them together. Very prone to trouble.

The loco I'm looking at was given to me by someone, and I see that it's been modified: someone soldered wires from the top contact strip on the motor to each of the truck tab contacts, and thrown away that long contact strip. It's actually pretty easy to do if you have any soldering skills and tools.

Cleaning the wheels is probably the most important thing you can do to get the loco running better. There are lots of techniques. I'd advise against sandpaper, unless it's *really* fine (at least 600 grit).

Better is to get the loco running upside-down (by using alligator clips to supply power) and use a Q-tip wetted with a solvent. Denatured alcohol works really well. Don't use rubbing alcohol. You should see lots of black gunk come off on the swab. This is something that needs to be done regularly, by the way, once you start actually running trains. Dirt continually builds up on the tracks and wheels.

Ah, running it upside down. I like that. I have denatured alcohol.

I have no idea what grit I used for the initial sandpaper. It did work pretty well. Before using it, I couldn't get the engine to move at all. I should do it again though, probably with something less than 600 just to make sure. What about fine emery cloth?

They are one and the same.

-- Ray

On 8/18/2009 8:31 PM Ray Haddad spake thus:

[groan] Oh, no, more misstatements of fact from the master himself.

Rubbing alcohol is isopropyl alcohol + water.

Denatured alcohol is ethanol (ethyl alcohol), denatured with methanol (methyl alcohol).

Not the same thing at all.

On 8/18/2009 7:20 PM W. eWatson spake thus:

I'd say don't use any abrasives. You probably don't need it to clean the gunk off the wheels, so why take chances with ruining the shape of the wheel treads?

They are the same.

-- Ray

OK, but use something finer than 600 - 1200 will do nicely.

Erm, "denatured alcohol" usually refers to methanol with an odorous addition, sold in a hardware or builder's supply store, while rubbing alcohol is isopropanol, sold in a drugstore.

Cheers, wolf k.

Where? If these two products are called by the same name in Oz, I'd be afraid to buy the stuff. Maybe you have different names for denatured alky and the stuff for rubbing. If so, what are they?

Cheers, wolf k.

Denaturing is done to rubbing alcohol. What these yokels are doing is confusing 90% alcohol with 70% alcohol.

Over here, it's called methylated spirits. It's denatured alcohol.

I'll bet they don't even know what denatured means.

-- Ray

Both are denatured.

-- Ray

Oh, I see what you mean. Well, over here we use "denatured" for what you call "methylated spirits", and "rubbing alcohol" for both 70% and 90% isopropanol.

Now don't you go and do Greg Procter and claim we are misusing the language. We know perfectly well what we mean by those terms, so we don't get the wrong stuff by mistake, and that's what matters.

cheers, wolf k.

On 8/19/2009 6:49 AM Wolf K spake thus:

Well, I'm going to be forgiving here and let Ray go on believing that denatured and rubbing alcohols are one and the same. After all, if he confuses the two and rubs some denatured alcohol on his skin, there's just a chance of an adverse reaction which might just shut him up, at least for a little while:

POISON! DANGER! VAPOR HARMFUL. MAY BE FATAL OR CAUSE BLINDNESS IF SWALLOWED. HARMFUL IF INHALED OR ABSORBED THROUGH SKIN. CANNOT BE MADE NONPOISONOUS. FLAMMABLE LIQUID AND VAPOR. CAUSES IRRITATION TO SKIN, EYES AND RESPIRATORY TRACT. AFFECTS CENTRAL NERVOUS SYSTEM AND LIVER.

(from the MSDS for methyl alcohol,

On 8/19/2009 10:13 AM Wolf K spake thus:

At the risk of flogging an already-dead horse, denatured alcohol is so called because it is "natural" alcohol (i.e., ethanol) that's been rendered undrinkable by the addition of poison (methanol). The idea, apparently, is to discourage people from making bloody Marys and margaritas from it. Rubbing alcohol is not called denatured because isopropyl alcohol is not drinkable as ethanol is.

You're confused. As usual. Both Isopropal and Ethyl alcohols are generically called "rubbing alcohols", but only the Ethyl variations are ever "denatured".

That's because "denaturing" means adding something that makes the normally palatable Ethyl alcohol toxic to prevent it being used as a beverage, whereas Isopropal alcohol is toxic to begin with, so cannot be "denatured".

No, those are just variations of how much water there is in a given mixture.

Bets?

(You can apologise any time now, but we won't hold our collective breaths.)

~Pete

Why? You just proved I was correct. Your attempt at apology is noted but declined, Pete.

-- Ray

And thus you prove me correct. But you will never admit it.

-- Ray

[...]

I don't follow your logic, Ray. DN has just pointed out that we use the term "denatured" to refer to ethanol with methanol added. Rubbing alcohol doesn't have methanol added, leastways not here. Just water, for the 70% stuff. So it's not denatured. Do you use "denatured" to mean the stuff is undrinkable? Or do you Ozzies add methanol to isopropanol? Or what?

Just asking wolf k.

Ray, you are in a minority of one (as usual). Everyone else, rest assured that other Australians do not have the same misconceptions, even though the term rubbing alcohol is not in very common use here.