Old (non-decoder ready) Kato F7 and bearing blocks

[turbowhiz]

I picked up an early run Kato F3 for the right price at a show recently (F unit close coupling needs to be in the cards at some point, and clearances are a challenge), and despite getting it running fairly decently after some tuning (magnet loose on the motor rubbing on the armature didn't do it any favors... is that a common issue?) it wasn't quite up to the Kato goodness I'd expected. I discovered that noisyish early run Kato F units were the norm, and figured I did what I could.

After seeing this post i finally got around to trying this bearing block removal improvement, and it made a world if difference! Great success for me on my circa 1990 F3.

Still learning the tricks of the scale, and this is a good one!

[peteski]

Assuming that the motor used in the F-units is the one with flywheels in the photo, magnets in those motors are only retained by the plastic end inserts and by magnetic force, so they are not permanently glued in. They can slide slightly to the sides, but I have never seen or heard of one of those magnets slipping down to touch the armature.

The electric pickup system on the early Katos (like this one and Atlas/Kato RS-3 and RS-11 is not optimal, but IMO they were still the best mechanisms when they were new (when compared to non-Kato brands), and as we all see, they greatly improved going forward, starting with the U30Cs.  Actually the GP38-2s which I believe came out before the F-units were excellent and quiet runners.

[randgust]

Until the pickup strips came along, the pickup on the early Katos could be iffy.  The truck internal bearing frames had to rub against the frame for electrical contact, both a cast zinc alloy that could slowly corrode.  They were so heavy, and there were flywheels, that is usually worked pretty well.  But still no where near as well as end-axles with pickup strips.

I've permanently MU'd my stump-pulling Kato GP38-2 with an Atlas Kato GP35 just to improve pickup.  Man, is that pair a powerhouse.

The GP38 was one of the oddest puzzles ever made, nearly impossible to modify or work on, but remains my champion 4-axle puller.

The new F-units move the pickup strips to the top of the frame instead of the bottom, no harm, no foul.  In my case, 4 powered units may not pull as much, but WAY more than what I need for nine passenger cars.