Talking T Gauge

DanMacK · Posted: Fri Sep 05, 2008 10:49 am Post subject: Thoughts on T Gauge steam

Since I first heard about T gauge (and found A.A. Sherwood's models over a decade ago), I've been fascinated by small trains (That's why I got into Z gauge). Sherwood's 4-6-2 was a marvel of engineering, and I always thought if he could do that in the 70's, why can't we do that now?

I've been thinking about how to do a T-gauge steam loco, and I come to 2 feasible options. Powered tender and dummy loco or possibly use the Eishindo drive truck as a pilot or trailing truck and have the drivers idle.

I'm not sure how one would fit a solid frame with a drive gear into only approx 2.5mm, but I'm sure that could also be done. Hardest part would be getting accurate sized drivers, but possibly Z scale could serve a function here. A 72 inch diameter driver is 4mm in T gauge, possibly Marklin or Micro-trains wheels could serve a function here. Micro trains wheels would be blind (no spokes), but could be used for testing (possibly mill out and put etched spokes in the centre?

I'm interested in what everyone's thinking on this.

Regards,
Dan MacKellar

Skibbe · Joined: 05 Sep 2008 Posts: 11

Shicoh Engineering makes smaller motors that are 3.2mm and 2.8mm in diameter... not quite the 2.5mm you're looking for, but may allow hood units. I have no idea if they have enough torque to get you anywhere either... but building your own gearboxes from Mikrotriebe or Didel .2mm modulus gears may be an option there.
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Mike Skibbe

DanMacK · Posted: Fri Sep 05, 2008 1:15 pm Post subject:

Totally forgot about Didel, but the current motor should be sufficient. possibly have MU'd locos if the smaller motors aren't up to the task?

I was more worried about the frame and getting it to roll freely. Possibly drive the tender, but you would need at least a 40' tender, pretty rare for smaller locos. Possibly power a car behind as well and use the loco as a dummy for power pickup.

The hardest thing I think would be making the frame if one was to do a powered loco, as the halves would have to be insulated if it was done in brass. Plastic or insulated drivers are also an option and pickup through the pilot and trailing wheels as well as the tender, no need to really worry about wipers on the drivers, just gears.

Loco and tender would pretty much be an integral unit at this scale.

pray59 · Joined: 05 Sep 2008 Posts: 88 Location: Fremont, CA

I have been doing all kinds of experiments, and came to the conclusion that as many cars as possible should be powered. When one stalls, the others push and conductivity is restored. Only the steamer and tender up front do not need to be powered, but everything else should be.

I ran a train with 6 powered cars, and even though they all run at different speeds by themselves, they run at very acceptable slow speeds when there is 6 powered cars running. Might just be enough combined torque to push a malley with magnet wheels.

Yes I think that a free rolling mechanism with magnetic drivers might track best, maybe just adding electrical pickup for the headlight and a firebox flicker that starts at <1 volt. The run several powered cars behind it to push the train.
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-Robert Ray

TBA · Joined: 08 Sep 2008 Posts: 120 Location: Massachusetts

If someone makes micro-sized universal joints, you could put the motor in the tender and a gearbox in the loco chassis.

shashinka · Joined: 04 Sep 2008 Posts: 24 Location: Maryland

DanMacK · Posted: Tue Sep 09, 2008 10:48 am Post subject:

I was thinking along the lines of 50' boxcars and/or baggage cars as pushers. that way you can have either a freight or passenger train and use the same loco. Of course if you have a 4-6-2 and a 2-8-2 say, you can use the loco and tender as pickup as well.

It'll be interesting to see what possibilities there are, I'm looking forward to ordering some soon.

DanMacK · Posted: Sat Sep 27, 2008 1:18 pm Post subject: More thoughts

I've been doing more thinking on this and looking at photos of the mechanism (still waiting to get money to order mine Sad

) Anyway, I've drawn up a T Gauge 4-8-4 based on Canadian National U2 class dimensions and it occurred to me that it would be possible to power the trailing truck.

This would allow the traction with the magnetic wheels and the current chassis could be used as a base. I was thinking brass for the loco frame, and if the centres f the drivers are plastic, then it should be relatively easy to use a block of brass for the driver chassis.

Height over the boiler is 9mm, and from what David S has said, this shouldn't pose a clearance issue. Wrapper would have to be thin, but it is doable. Front could be weighted down with lead shot or even tungsten if one could find it. This coupled with the brass bolster block for the drivers could add sfficient weight (rolling stock would be powered as well of course)

Bigger locos are definitely preferable to smaller ones in T for obvious reasons. Just for fun I scaled down a Challenger and with tender, it was less than 4" long.

Drivers I was thinking could be turned from 5mm steel tubing with styrene tubing for centres and possibly brass for axles. By telescoping these (Steel, styrene tube, brass tube and brass or steel axle), a simple yet effective driver could be constructed rather quickly and inexpensively.

Tender trucks, depending, would have to be either scratchbuilt or kitbashed from existing eishindo trucks. Pickup would be through the pilot wheels on the loco as well as the tender. could also include the drivers in that mix as well.

Rods may have to be ethed from stainless steel.

Once again, these are just thoughts, comments welcomed
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Regards,
Dan MacKellar

TBA · Joined: 08 Sep 2008 Posts: 120 Location: Massachusetts

I thought this Boston & Albany 4-6-6T might be doable, in simplified form.

http://public.fotki.com/BrianAustin/reference_library/architectural_and/railroad_reference/ba466.html

The drive could fit in the bunker/cab/firebox, but then the motor would have to be moved up into the boiler to clear the drive wheels (which could be non-movable dummies). Here's where a worm-gear drive would have to come into play, as presently the motor is mounted low in the chassis.

The other main issue, which applies to almost all steam locos, is the lead truck, which is of the inside-bearing type. Judging by the photos posted, the T-Gauge cars have fat axles, which complicates matters. I suppose one handy with a lathe and photo-etch could whip up some a new truck in metal. One could overlook the discrepancy and use a stock T-Gauge truck, but then I think the cylinders would be in the way. Maybe mount fake cylinders on the truck sideframes? It would look funny on curves.

Then there's the matter of making and mounting drive rods...

Very Happy

TBA · Joined: 08 Sep 2008 Posts: 120 Location: Massachusetts

I neglected to mention the loco I posted above ran on a commuter branch (in and out of Boston, MA), so you could just disguise the T-Gauge power cars as coaches instead of worrying about fitting the motor in the loco.

DanMacK · Posted: Thu Oct 16, 2008 4:56 pm Post subject:

Commuter locos would be perfect.

Below is a possible proposed mechanism for a 4-8-4. The tender trucks are actually commonwealth, but given the size, a 3 axle sideframe could be used for the eishindo trucks and stand up under all but close scrutiny.

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Regards,
Dan MacKellar

Will J · Joined: 04 Sep 2008 Posts: 2 Location: Kidderminster UK

~post moved to narrow gauge section!~