Will they run together?

(I posted this on the Yahoo! Group The HO Scale Model Railroad Club, and got no response, so I'm reposting it here.)

I picked up several new locomotives a short time ago, and even though they're the same make and model, they have drastically different speeds. In your experience, have new locomotives smoothed out and started to run the same speed as they got broken in, or is the speed of the locomotive pretty constant throughout its lifetime?

Puckdropper

Reply to
Puckdropper
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Some do, some don't. It's not that simple, sadly. Usually, the ones I had ran faster or slower out of the box, and stayed that way. They always got slightly faster after they broke in though. If the mechanism was really bad, they either burned out, or became much faster once the gears wore smooth. I had a couple of N Locos that were so bad I had to take them totally apart and clean the molding flash or burrs off of the gears to unbind them. One had a mechanism that used a shaft with a gear that was supposed have a shaft that went through a gear, and that gear was supposed to be spun by a worm gear on one side, and then it was supposed to turn the wheels by turning the gear in the center of the shaft. When I got the loco, it barely moved and the front truck gear was so tight on the shaft, it bound it up almost to the point of not letting it move.

The brass gears were pretty crude, and the hole in the one wasn't really round, it was egg shaped. The only way I could make the hole round was to make it bigger. I silver soldered the hole shut, and drilled a new hole slightly small, and used string with polishing compound on it and "lapped" the hole until it was exactly big enough to spin freely. Only took me two tries to get the hole exactly center. It really wasn't worth the effort. It was a POS, and never ran very well. It was one of the infamous made in Italy locos made by Lima.

BDK

Reply to
BDK

Thats a lot of work, reboring gears. I have a *honkin big* floor mounted drill press and dont like to do it even with the correct ol.

I've come to the conclusion that for any re gearing or gear repair, Northwest Short Line is my new best friend.

Reply to
jJim McLaughlin

On 2/19/2008 6:49 PM BDK spake thus:

There's always that old trick of filling the gearboxes with toothpaste and running them for a while to lap the gears. This helped a lot with my Roundhouse Shay kit.

Reply to
David Nebenzahl

Yeah, I did that on some of mine, but that one had so many hunks of brass on the teeth areas of the gears along with the hole issue, I had to take them all apart. I saw one on Ebay last year, it looked like it was new, but he said it barely ran.

BDK

Reply to
BDK

I had one of those little drill presses they used to sell, and clamped the gear down with adhesive tape to keep it from getting gouged up, and just missed it by about 1/32" the first time. The second time I nailed it. But I should have done what I was going to do, and eventually had to, make it into a dummy in the first place. It was a fine dummy unit. I used to stick it on the back of my 2 Con Cor PA-1s, one painted that yucky NYC green, the second, after it was scratched, in PC black, and then the dummy, in what the box said PRR Tuscan Red, but was actually an odd brown. Paint was done well, but it was flat out the wrong color.

BDK

Reply to
BDK

go add that comment to the "MDC HO and HOn3 Shays?" thread! It will be useful there as well...

Reply to
Big Rich Soprano

Welcome to mass production which makes that statement a dream... sad to say...

Reply to
Big Rich Soprano

A lot of my old ones that were the same model that ran at different speeds just had different motors or different looking armatures in them.

BDK

Reply to
BDK

David Starr wrote in news:47bc8868$0$22874$ snipped-for-privacy@roadrunner.com:

They're MRC F7Bs. The mechanisms all look to be the same, but the circuit boards were installed contrary to their labeling. (There's nothing on the circuit boards except circuit traces. It's obviously to faciliate installation of a decoder.)

I'll have to take a detailed look at the mechanisms and see what's going on. They apparently sat on a warehouse shelf for a long time, so anything's possible.

That's a good idea. With the MRC boards, it's easy to temporarily install an ammeter, too!

Puckdropper

Reply to
Puckdropper

A better tool is a lathe. It's really pretty simple with the right tool.

Reply to
<wkaiser

Does that still work? I used to do it, but new toothpastes seem to be much less abrasive than the ones from years ago.

Reply to
<wkaiser

On 2/21/2008 8:26 AM snipped-for-privacy@mtholyoke.edu spake thus:

Worked pretty well a couple of years ago for me; I think I used Tom's (of Maine) hippy-dippy organic stuff.

You could always mix your own lapping compound with something like rouge, rottenstone or another fine abrasive.

Reply to
David Nebenzahl

How about using Soft Scrub as a lapping compound? It is more abrasive than toothpaste.

Reply to
Frank A. Rosenbaum

On 2/21/2008 11:46 AM Frank A. Rosenbaum spake thus:

Sure, that might be just the trick for such gears as are found on the Roundhouse Shay, which need lots of grinding down.

Once again, Frank, could you *please* fix your newsreader posting settings? Everything below your reply above gets cut off as part of your sig. It really can't be that hard to do. (I see you're using Microsoft Windows Mail 6.0.6000.16480.)

Reply to
David Nebenzahl

Gleem is still around, and still makes nice polishing compound for fixing clear plastic panels like displays on radios, and anything else that needs a really smooth polish job. Smells minty forever afterwards though. Really.

BDK

Reply to
BDK

Pearl Drops worked fairly well for me.

Paul

Reply to
Paul Newhouse

Never tried that!

BDK

Reply to
BDK

If he wouldn't top post, there wouldn't be an issue. {;^)

Reply to
Brian Smith

Agreed. I don't know why people started doing it this way on the internet. Back in the good old days of the BBS (Bulletin Board Systems), the quotes always came first followed by the replies...much easier to follow along with the thread. But for some reason when people started participating in the same type of online text discussion groups on the internet, they for some reason seem to want to move the quotes to the bottom.

Reply to
bladeslinger

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