Prague T3 Trams

[railsquid]

DIY front lighting:

 

 

[bill937ca]

On 12/21/2022 at 3:46 PM, brill27mcb said:

Bill, you are a dangerous person! 🙂

I was avoiding buying any of the Tatra trams until your posts overwhelmed my better sense. Now they are on order.

 

My T3 is here so I have fulfilled my dangerous person status (at least with one East Penn Trolley Club member).

Edited December 30, 2022 by bill937ca

[bill937ca]

For the record now that I have the model we can look at the dimensions . Is it 1/150 or 1/160?

 

The body length of a T3 is 14,000mm. At 1/150 this would be 93.33 mm. A 1/160 this would be 87.50 mm The difference is 5.83 mm or 15/64 inches (0.22952755906 inches), less than a  quarter of an inch.

 

I will measure my car in better light tomorrow.

 

The car is a T3SUCS which were built in the 1980s.

 

A two-car set runs with both pantographs up.  Pantographs are painted yellow RAL 1003 (cz6200) in Prague (although 6892 has red pantographs because it is in the old regime's paint colors.

 

At night the cab is pitch black to prevent windshield glare and the body has fluorescent lighting so it is very bright.

 

These cars use what is called a Prague coupler with a mechanical head. To me it is a drawbar.  There are power cables connecting the two cars. This would low voltage items and control functions. Traction power is fed by the pantographs (quite different that US PCCs). There are drawbars in the box to connect the cars. I think the coupler in the HS photos is a dummy.

 

I wondered about the headlights when I first saw them. This 6892 of an earlier T3 variation on Route 23 and the headlights look pretty accurate.

 

 

Edited January 1, 2023 by bill937ca

[brill27mcb]

Hi Bill,

 

Check the width measurement, too, please. There is no guarantee that all dimensions are scaled equally, especially when a model body shell needs to be designed to fit an existing multi-use power chassis. I always doubt stated modeling scales and prefer to measure the model against the prototype measurements. (This is even more true for model automobiles and trucks).

 

Looks like we will also have to make our shiny silver wheels and gray plastic bogie bits look grimy.

 

On the Tatra models, Tomytec provides two styles of coupling bars - one straight and one that dips down. The straight one will work with Tomix 140mm radius mini curves and looks more realistic. Like most coupled trams, these will not work with an immediate zig-zag of right/left or left/right curved track pieces. The coupled cars end up pulling each other sideways off the rails when the car ends swing outward in opposite directions. Even a short intermediate straight track piece can solve that.

 

Rich K.

[bill937ca]

I measured today with a metric ruler and got 87mm for the body length which matches the figure published by DM Toys.  That would make it 1/160 on that measurement. But that is just the underside of the body and to fit an existing power chassis.

[magnuse]

12 hours ago, brill27mcb said:

 

On the Tatra models, Tomytec provides two styles of coupling bars - one straight and one that dips down. The straight one will work with Tomix 140mm radius mini curves and looks more realistic. 

 

Rich K.

Hi Rich, 

What curve radius is possible with the coupler that dips down? Can you post pictures of the two coupler variants? 

 

Regards

Magnus 

 

[bill937ca]

This is the coupler have dips down. I think it is a non-functional dummy.   Usually that type of coupler requires a third piece that attaches to the two drawbars.

 

The next photo shows the prototype.  Prague mechanical couplers along with jumper cables.  Photo was taken at Masarykovo Nadrazi.

 

I haven't got a photo of the drawbar yet.

Edited January 2, 2023 by bill937ca

[bill937ca]

Working on the couplers for the T3 today.

Underside of the T3 out of the box.

 

I've gently  removed the body from the T3. My tool of choice is a toothpick Because of the tamper of the body, I pried from the ends.

 

The interior is separated from the chassis. The two black rectangles in the chassis are weights.  The cab is semi-enclosed and the back platform has no seats and is a popular place to stand or shoot video from.

 

I have now gently pulled the Prague coupler out of its setting.  This is the end that will connect to the second car of the set.

 

The power chassis with the drawbar and anchor piece attached.

 

View of the underside.

Edited January 2, 2023 by bill937ca

[bill937ca]

In the next step I have transferred the side frames from the static chassis to the power chassis. Thumb nail pressure was sufficient to remove the  side frames.

 

 

There are stickers included for additional options for both Prague and Leipzig trams in the package.  The Prague stickers are in line with the red and cream Prague tram end showing the correct positioning for each sticker.

Edited January 2, 2023 by bill937ca

[bill937ca]

That is probably all for today.  I need how to attach the Prague coupler from the front of the motor car to the second car.  The drawbar does not fit through the fender on the second car and it seems the coupler attachment piece on the static chassis will not separate from the rest of the static chassis. Also my natural light is fading.

Edited January 2, 2023 by bill937ca

[brill27mcb]

On 1/1/2023 at 5:04 AM, magnuse said:

Hi Rich, 

What curve radius is possible with the coupler that dips down? Can you post pictures of the two coupler variants? 

 

Regards

Magnus 

 

 

Hi Magnus,

 

Short answer, after I did some testing, is that 2 Tatra trams coupled with the straight scale-looking drawbar can operate around the Tomix "Mini" 140mm radius curves (or Kato R150 curves). If you use the alternative less-scale drawbar that dips down, they can operate around the tighter Tomix "Super Mini" 103mm radius curves (or Kato R117 curves). I always recommend that people use the "Mini" 140mm and 177mm curves, and only use the 103mm "Super Mini" if they run nothing but short single units that can handle such a tight curve. A longer answer follows.

 

Rich K.

[brill27mcb]

23 hours ago, bill937ca said:

That is probably all for today.  I need how to attach the Prague coupler from the front of the motor car to the second car.  The drawbar does not fit through the fender on the second car and it seems the coupler attachment piece on the static chassis will not separate from the rest of the static chassis. Also my natural light is fading.

 

Hi Bill,

 

Let me start with some nomenclature:

1. I will call the coupler pieces that come mounted on the Tatra trams "dummy couplers" as you do. There are many prototype variations of this basic design (in North America Tomlinson couplers were common on trolleys and interurbans). They are flat-faced with slightly off-center protruding pins or lugs that fasten into an opening on the mating coupler, side-by-side. No separate link piece is needed, as with old "link and pin" couplers.

2. I will call the straight piece made to look like two dummy couplers coupled together a "coupling." It has a boxy representation of the coupler heads at the center, and is intended to protrude out from the opening under the ends of the cars.

3. I will call the dip-down piece a "drawbar" since it has no attempt to model the coupler heads and is really just a model drawbar. It is meant to come out from under the front opening of the car, not through it. It is included in case you want to run these trams on curves tighter than 140mm radius.

 

The best and most useful illustration of the "coupling" and the "drawbar" is on the right-hand side of the Tomytec instruction sheet:

https://www.1999.co.jp/eng/image/10901232/50/1

 

Looking at your photos, it looks like you have put the dip-down "drawbar" out of the front opening (and upside-down). It may not work well that way. I would swap it out for the straight "coupling," which will look better, too. (I snap my removed "dummy couplers" onto the removed unpowered chassis just to keep everything in one place, as I save the removed pieces.)

 

It was good of Tomytec to provide two of both the "coupling" and the "drawbar". Good to have spares of small pieces! Because of the coupler provision, this model does not use the standard add-on power chassis end extensions that come with the TM-TR01 power chassis, which is why special ones are included with the unpowered models themselves. Unfortunately, I do not see any way to use the small weights that come with the TM-TR01s with these special extensions, other than just finding an empty spot to glue them somewhere inside the car shell. I think the power unit would benefit from the extra weight.

 

The trams look good on your layout!

 

Rich K.

[Aleks]

I just got myself two single red (Prague) T3 cars and a double cream (Germany) set. I wanted to get a red double set but they were sold out online...

 

It's nice they made T3 sets with steel wheels (even without a motor), because this way you can couple two or maybe even three and operate them as a set, with just one motored truck. The inscription says they won't be able to pass the super mini curve (103mm). I bought some recently too and will aim to test how it works and if it doesn't, why. I wonder if it may be the plastic body getting in the way, as it's not the truck itself.

 

In Japan, at IMON Oimachi (and only there) last week I saw the red T3 double set... this was oh so tempting to buy, but I figured out I already have four T3 cars... so I did resist.

[brill27mcb]

Hi Aleks,

 

Today I ran a 2-tram train around 103mm curves with no problem, backwards as well as forwards, by using the dip-down drawbar. So it works. With the straight coupling, that coupling piece hits the edge of the opening at the bottom of the tram end as it pivots. The dip-down drawbar protrudes out below and outside of the opening, so the opening edges do not limit its swing.

 

What won't work is having an immediate transition between right and left curves. At that point the drawbar starts pulling the trams off the track sideways (the ends swing out in opposite directions and fight each other), so it's best to have a straight between opposing curves. This will all be clear to you when you experiment with them yourself.

 

What interests me is that the way Tomytec offers these models, the second tram in the 2-tram sets has no power chassis extensions included for it, so you will always have a trailer that can't readily be motorized. Of course, you can choose which of the three available tram numbers you want to power (or remain unpowered).

 

Good luck resisting! 🤔  I'm pretty sure Hobby Search will be getting more, and that ModelTrainPlus, Plaza Japan and others will be getting more in stock, and at reasonable prices.

 

Rich K.

[bill937ca]

1 hour ago, brill27mcb said:

Good luck resisting! 🤔  I'm pretty sure Hobby Search will be getting more, and that ModelTrainPlus, Plaza Japan and others will be getting more in stock, and at reasonable prices.

 

Rich K.

Hobby Search is back on  January 5th after the Japanese New Year's holiday and inventory, and the other outlets should be back on January 4th.

[bill937ca]

It appears the prototype couplers come from Alfa Union, a Czech company.  they just call them couplers.

 

https://www.alfaunion.cz/en/products-couplers-detail-79

 

Here's a profile of 7205 which is still active from http://tram.mobilnitabla.cz/seznam_vozu

 

Home depot : Hloubětín

Current depot : Střešovice (from 27.7.2019)

Car type : T3SUCS

Low floor : NO

Manufacturer : Tatra Smíchov/ČKD

Year of manufacture : 1987

In operation since : 1987

Production number : 176294

Profile number: VM- U13

Doors : Tatra, classic folding

Seats : Vertex / Plastimat Hradec Králové, laminate shell. Development: plastic materials center ČKD Prague. Design: Miroslav Navrátil

Central OIS computer : Apex DT-06

 

Front coupling : "Prague" with mechanical head

Rear coupling : "Prague" with mechanical head

 

Current collector : Pantograph KE 13M (standard "cage")

Mileage: approx. 1,648,587 km

Dimensions:Total length including couplers: 15.1 m
Length of cabinet separately: 14 m
Width: 2500 mm
Height: 3100 mm
Distance between pins: 6400 mm
Wheelbase: 1900 mm
Floor height above the top of the rail: 900 mm

Number of seats:24

Number of places to stand:138

Maximum occupancy:162 people (with 8 people per m 2 )

Mass:Without passengers: 15800 kg
Maximum load: 27200 kg
Chassis weight: 3700 kg

Axle load:Empty: 41.7 kN
Maximum load: 65 kN

Regulation:99 Degree Accelerator TR37/040

Controller:HG14/24

Controller stages:5x drive (220A,290A,360A,420A,480A)
5x brake (140A,170A,210A,250A,340A)
2x rail brake (at the same time as the fifth stage of the electrodynamic brake)

Collector:Pantograph EC 13M

Brake:LA11

Coupling:"Prague" with a mechanical head

PTO shaft:Elbe/Soko

Transmission:PP 7,43

Wheel type and diameter:700 mm with flexible insert

Brakes:Jaw brake MB225, rail brake FC33 60kN

Traction engine:4x TE022/TE022J

Motor input voltage:=300 V

Engine parameters:Power: 40 kW
Speed: 1750 rpm.
Max. speed: 4200 rpm
Excitation: serial
Cooling: motor fan

Motor generator:SMD16Ab
Power: 5 kW
Speed: 1750 rpm.
Max. speed: 4200 rpm
Excitation: serial
Cooling: motor fan

Door:ČKD, drive ČKD/MEZ TS030-DS7

Seats:Laminate

 

Livery:

cream RAL 1015 (cz6050)
red RAL 3020 (cz8140)
roof + seat base: gray RAL 7043 (cz1100)
bottom: gray RAL 7021
collector: yellow RAL 1003 (cz6200)
bumpers: brown RAL 8017
registration numbers: yellow RAL 1018

[Aleks]

I wish there was a way to easily change the number on the tram when you have more than one of the same kind. Would be kind of cool to have an entire network operated with Tatra 3s, as they were in so many cities. Although I do remember seeing it and thinking it was boring in the day :).

[bill937ca]

33 minutes ago, Aleks said:

I wish there was a way to easily change the number on the tram when you have more than one of the same kind. Would be kind of cool to have an entire network operated with Tatra 3s, as they were in so many cities. Although I do remember seeing it and thinking it was boring in the day :).

Yeah, Tomytec supplied alternate Prague route numbers but no alternate car numbers.

[bill937ca]

After a couple of busy days, I have completed the coupler project. Some more photos to document this.

 

Various pieces in the package.

 

Underside of the power chassis with the two extensions added.

 

Power chassis with the couplers attached. The dummy coupler is on the left.

 

The power chassis attached to the second car of the set.

 

Completed two car set.

Edited January 5, 2023 by bill937ca

[bill937ca]

On the layout.  The layout will undergo a modification to a simple oval to make it easier to run the T3s.  The present oval with an S curve was designed for the Kato LEX and Kato My Tram units capable of R90 curves.  More on this later in my layout thread. 

 

Edited January 5, 2023 by bill937ca

[bill937ca]

On 1/3/2023 at 2:29 PM, brill27mcb said:

 

Hi Bill,

 

Let me start with some nomenclature:

1. I will call the coupler pieces that come mounted on the Tatra trams "dummy couplers" as you do. There are many prototype variations of this basic design (in North America Tomlinson couplers were common on trolleys and interurbans). They are flat-faced with slightly off-center protruding pins or lugs that fasten into an opening on the mating coupler, side-by-side. No separate link piece is needed, as with old "link and pin" couplers.

 

2. I will call the straight piece made to look like two dummy couplers coupled together a "coupling." It has a boxy representation of the coupler heads at the center, and is intended to protrude out from the opening under the ends of the cars.

 

3. I will call the dip-down piece a "drawbar" since it has no attempt to model the coupler heads and is really just a model drawbar. It is meant to come out from under the front opening of the car, not through it. It is included in case you want to run these trams on curves tighter than 140mm radius.

 

The best and most useful illustration of the "coupling" and the "drawbar" is on the right-hand side of the Tomytec instruction sheet:

https://www.1999.co.jp/eng/image/10901232/50/1

 

Let's put some photos for identification purposes with Rich's description of the various pieces on the tram and in the package.

 

Dummy coupler.  Strictly decorative, not intended to connect anything. Usually visible on the front or back of a tram or tram set.

 

The Prague coupler (coupling) seen between the two tram cars. Restricted to R140.

 

Drawbar. Between trams for situations where you need a little more leeway.

 

The round thing in the cutout square is the tab these various pieces attach to. This is not visble with the body on the chassis.

Edited January 5, 2023 by bill937ca

[brill27mcb]

The trams are looking good, Bill. Too bad the reverse curve causes a problem, because it (visible in your earlier posts in the Garage Unit Tram Layout thread) adds interest to the layout.

 

 

Your documentary photos certainly clarify things for everyone.

 

Rich K.

Edited January 6, 2023 by brill27mcb

[bill937ca]

I have pretty well set up the revised layout.  Photos in the morning!

 

Thank your for the definitions. They really helped explain everything.

Edited January 6, 2023 by bill937ca

[bill937ca]

Another view of the Tomytec Prague Tram from the UK.  They also remarked on the lack of additional chassis extenders and need for he underfloor coupling to negotiate R103 curves.  I think the coupling is tighter than the prototype.

 

https://www.rmweb.co.uk/topic/176351-tomytec-n-gauge-prague-tatra-t3-trams/

Edited January 7, 2023 by bill937ca

[bill937ca]

Another video showing assembly and with  English sub-titles.  Video by Tulyar 樽屋 (Ottersgrove).