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Loco woes

I stopped by a local store (MJ-Hobby in Stockholm) on the way home from work yesterday and managed to pick up the only used Marklin transformer they had left. At SEK 450 (~$50US) for a measly 10 VA unit, I don't really consider it "cheap" but it served me to get started on my restoration project and it'll do for "secondary" power once I get going. I always ran separate power feeds to rail and catenary, so I could operate two locos on the same analogue Ma rail. As long as the 10 VA unit only has to feed a "small" loco and all auxilliary load (lights, turnouts) are handled by a "better" unit, it'll run.

So I opened up the trusty old Da 884 (Ma part # 3030.1, according to one web site) and oiled it up and gave it new brushes. At first it only ran very slowly, barely turning over even at full power but after a while it spun up and started going quite nicely. But after I'd let it sit and rest for a bit while I serviced another loco, it seemes to "seize" up again so when I tried to run it it was again very slow at first. Then, after about a minute or so, it picked up again.

Does anybody have clues as to what may be wrong? Is my oil too thick so that it needs heating up before running smoothly?

The other loco I looked over was a sad story. It's my first little steam loco that I got with a starter kit in 1964/5 and I fear the motor armature bearings are shot. It screams quite loudly with resonances at certain speeds. Is there any way to salvage it? Mind you, it's not a particularly "nice" loco. I see Marklin still have an almost identical one in one of their current starter kits. The only difference is tha mine says "Marklin 3029" on the cab side while the current issue tries to pin the blame on Swiss SBB. Anyways, it may be that I'm better off buying a new starter kit at $150 and get a 30 VA transformer plus some C-rails and a replacement steam loco for Junior to play with, rather than pay $100 for just a transformer. Unless, of course, there is some secret way to "re-pack" the armature bearings. Experiences, anybody?

/Torsten

Reply to
Torsten Lif
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I am not that familiar with Marklin, but. . . .

When a loco 'screams' and has jerkey movements it needs just a drop of oil on the armature shaft as it enters and leaves the bearings. If you can't get inside the motor then just put a drop where the shaft exits the motor. Use a light, plastic compatible lube.

For the loco that starts slow and then speeds up, you might have gotten oil on the commutator. Another thought is that the brushes might not be seated properly. Some brushes are contoured to fit around the commutator. If yours are and you put them in wrong then there is very little contact area for the electricity.

I hope this helps.

Frank in Portage, Michigan

Reply to
Frank Rosenbaum

Torst Lif wrote: [...]

Adding to Frank's advice: get a good contact cleaner-lubricator and put a small drop on the commutator. It will clean up that item like magic. In my experience, it reduces current consumption by 20-50% (!) in DC perm-mag motors. Aero-car makes a really good variety. I'd be happy to send you some. E-mail me off list if interested, and we can work out a trade; I'm interested in Epoche IIIa rolling stock (HO), and will happily trade for 2nd hand items. Drop the 'e' in the reply to.

If the armature bearings are the sintered variety, you're out of luck IMO - they have just worn too much. That sintered bronze is rather soft. OTOH, you could try a slightly heavier grade of oil. You could also try a washer between the aramature end and the bearing, if you can get it in there, one that allows ca. 0.01mm play or less -- just enough that the armature spins freely. Reduced endplay will sometimes reduce the squeal. (I've improved motors with about 1mm endplay this way.) But IMO you're right: put the loco on the display shelf and get a new starter set. Allowing for inflation, it's cheaper than the original was back in 1964, which may be some consoslation. :-)

HTH

Reply to
Wolf Kirchmeir

Worth a try. I'll see what I can find in the local electronics stores (I have two in the mall next to work, happy, happy :-))

Of course, mine are AC Marklins so the parameters are different.

Sorry, but I fear the shipping costs would be prohibitive.

/Torsten

Reply to
Torsten Lif

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