DB VT 798 Schienenbus

The Deutsche Bundesbahn  VT 798 Schienenbus (railbus) was probably the most characterful item of  DB rolling stock. The saved many a branch line from closure and having one to run on Niederwangen is clearly pretty essential.  The photo above shows one at Korbach in 1980. I spent several hours riding on these railbuses on that day.

Some time ago on a German cardboard modeller's forum there was a description of building this card kit from a pdf that one of the members, Daniel Kupfer, had designed and built. Daniel very kindly supplied me the pdf document which I'm now modifying to produce a working S Scale model. I believe the original model was for O scale.

The first problem to solve was to find a suitable power unit. I've used tramcar bogies for other locomotives and to my delight  I found that two of them when bolted together as in the photo gave me exactly the correct wheelbase for the railbus in S Scale. All that is necessary is to remove the wheels in the middle and solder to wires to join the pick up strips on each bogie together. I intend later to add some strengthening pieces to hold the two bogies together more securely.

The pdf has a two piece floor unit (necessary for a large O Scale model) but I combined the two halves to produce a template for the S Scale model.....

....which I cut out from 1mm thick mounting card. A rectangular hole was removed ....

....and this can then be dropped on top of the motor unit where it sits on the securing lugs at the end of each bogie. This will form the base of the body onto which everything will be constructed. The top surface is at 13mm above rail height which means it will need to be built up to 18mm to give the correct height for the internal floor of thee railbus.


The base of the body is secured to the power unit with small 10BA bolts and nuts using the brackets at the ends of the power unit. The nuts were trapped in place with a piece of mounting card which had as slot cut into it as in the photo above. The nut was held in place with some epoxy glue...

...before being trapped in place with another overlay of mounting card which had a small hole drilled in it to allow the end of the bolt to pass through.

The next stage is to build up the foundations of the floor. I cut two lengths of 5mm wide mounting card and glued these on top of the body base using the bolt overlays at either end to position them. An extra piece of card was cut to go on top of the overlays. This will gave solid mounting positions for the floor to be glued to later on and I will also add layers of card on top of the edges of the base (the pink coloured sections one either side).

The floor has now been added with packing pieces of mounting card added all along the sides of the base. It's now obvious how little the motors and gear wheel are going to intrude into the passenger compartment. The chassis runs smoothly and is capable of propelling several goods wagons so should easily handle one or two railbus trailers

I've now joined the two halves of the floor interior and resized it ready fro printing out.

The floor has been cut so as to fit one the slightly raised area over the motors. Two strips of  mounting card on either side raise the floor sufficiently to clear the motor.

So far construction has been simple but the body is likely to be a different matter.

After various experiments I've decided to start with the cabs and doors which are designed as two separate parts. The part above is for the lower half of the cab and doors whilst....

....this is for the cab windows and upper parts of the doors.

In this view I've glued the lower cab ends and doors to the base. To strengthen them and hold the sides in the correct positions I've cut some mounting card to roughly the correct size for the driver's control desk and the various cupboards to be found at the ends of the railbus. This sits on a curved piece of mounting board glued on the inside of the cab front.

The next step was to add the top half of the doors. These are strengthened and attached to the lower bodyside with a piece of card behind the door.

To form the cab windscreen I'd decided that using cardboard would not given sufficient strength so I'm going to use brass wire and brass strip to form the upper half of the cab front. Step one is to add some short lengths of brass tube glued onto the top of the door with epoxy. An L shaped piece of brass wire is soldered into the tube and glued onto the rear of the door to give some additional vertical strength. The tube and wire can be seen on the back of the far door. Then a piece of wire was soldered to the rear of the brass tube to give some stability to the cab doors.

Another length of wire was bent to the profile of the cab windscreen, when viewed from above. This was then slid into the brass tubes and will eventually be soldered in place.


The windscreen supports are all going to be made out of 3mm wide brass strip. The first stage is seen here with a strip bent to match the curved front of the vehicle and glued in place with epoxy resin.

Building the windscreen frame was done in stages:

  1. Solder a narrow 1mm wide strip of brass on to the front of the 3mm strip .

  2. Add the three vertical pieces from 2mm wide strip soldering them onto both the lower brass strip and to the wire at the top.

  3. Solder another 1mm strip at the top attaching it to the brass wire.

The result is a strong window frame area on to which glazing will be added after painting the body.

Having constructed the cab frames at either end the next stage is to add the main sides. The windows were cut out very carefully. Small diagonal cuts were made in the top and bottom corners of the windows to represent the rounded corners of the windows. A pin prick was made in all the other corners and then each window panel was cut out. Cyano adhesive was run along the edges of the windows to hard the cardboard.

A 9mm wide strip of mounting card was glued to the interior of the sides and will support the bottom of the side glazing. An inner body side was added after cutting out the window openings and will be used to trap the glazing strip in place . A strip of dark grey card is taking the place of glazing until after painting.

The seating and toilet walls have been added. Rather than use the fold up seating with the pdf kit (the parts are very small in S Scale) I decided to make them out of mounting card. The raised floor area above the motors means that the seats are 2 mm lower in the middle of  the model but after glazing this will hardly be noticeable.

On to the roof! Using the pdf kit I joined the two halves of what the kit calls the Dachkonsole (I'll call it the roof base) together and resized it to the correct length and breadth. After printing it out and cutting to the correct size I glued a 1mm wide plastic strip all the way round using liquid polystyrene cement. This gives a neat edge and will also be useful when painting the model as the paint can be scraped off to give a white stripe along the edge of the roof as seen on many photos of the BR798s. The card roof base is 48mm wide and with the plastic strips comes to about 49mm and just overlaps the edges of the card body.

 The pdf kit has the curved part of the roof in three sections. The problem with this is that domed ends with overlap joints don't look very realistic so I intend to build the roof ends in the same way as I did for my BR216 locomotive using stepped layers of card with layers of paper coated in epoxy resin adhesive.

The photo shows the first stages of the construction of the roof. The base with its plastic strip edging is complete. The centre section of the roof is 140mm long and 74mm wide. As I'm intending to make a Steurwagen (driving non-powered vehicle) I'm making a note of the sizes so that, in theory at least, the roofs should be the same height. The centre section of the roof is 24mm wide and the two sharply curved edges are each 6mm wide whilst the two flaps that secure the roof to the base are each 10mm wide.

The card was bent to the correct profile using a plastic tube for the edges and fingers for the domed centre section. I've also glued in place some flaps under the ends to act as supports for the domed ends. The underside of the card was coated in a layer of epoxy adhesive to strengthen it.

The method I use for producing the domed ends of the railbus is seen here.

 A card profile piece is glued vertically along the centre line and then a series of card "steps" are glued in place either side of this profile with the curved edges gradually getting smaller. It's very rough but the next stage turns them into the domed end.

The pdf kit has these strange shapes which I print out onto card. The triangular tabs are all cut off and the various curved slits are removed.

Next the whole area of the card "steps" is covered in epoxy adhesive and the underside of the paper also receives a thin layer of epoxy. The next step is messy and involves getting fingers covered with the adhesive. The paper is placed in the correct place at the end of the roof and gradually worked into place. As the adhesive begins to set the paper is worked into place with the fingers until eventually it is held in place. After the first layer is in place further paper layers will be laid on top of the first to give a firm roof.

There are a considerable number of stages of construction in this photo:

Some more progress has been made if you look carefully.

The final part of construction is to make a representation of the railbus underframe and motors. A piece of mounting card 8mm by 115 mm was cut and the axleboxes and springs from the pdf were printed on thin card and stuck in the correct positions at the ends of the strip. The layers of card were cut away around the springs as seen in the photo. The broad centre area of card will have the battery boxes and motor glued to it .

A thin layer of card was glued behind, overlapping the top edge by about 2mm,  and will be used to stengthen the joint when it is glued to the edge of the cut out section around the motor unit.

The completed motor unit, pipework and battery boxes. This is intended as a represntation rather than being accurate as photos of the underside of the Schienenbus are rare and almost always in deep shadow.

At the ends of the underframe I've added some of air tanks and a five sided box like structure. I used drinking straws (with the ends filled with epoxy resin) and laminated card  for these.

This completes the construction of the model and it is now ready for applying some wood hardener to the card to strengthen it and then painting.

The roof has had various pieces of card added to the underside so that when placed on to the body it is secured in place at the correct location. It will also help make the sides and ends much more rigid once it is finally glued in place.

Two views of the railbus now it has been painted and glazed.

The silver lining was done with a Pilot silver marker pen whilst a black overhead projector pen was used to represent the rubber window seals.

The cab glazing was done in sections with the two flat panels being cut from plastic sheet and the curved side panels being cut from curved clear plastic from the blister pack of a tube of adhesive. The windscreens are held in place at the bottom with small pieces of card together with epoxy resin adhesive.

The various air hoses and multiple unit cables have been added from brass wire.

Transfers are from Modellbahn Decals - they should really be cream but at present there don't seem to be any suitable ones available.  The class numbers and raucher/ nicht raucher signs come from a spare Umbauwagen kit whislt the DB 'Kek' logo is the smallest size as used on freight wagons. I may add the numbers in due course.

VS 998 Steuerwagen

Although the DB VT 98 railbuses were seen operating on their own it was more ususal to see them running as a two or three car set with a  VS 98 driving trailer or as a three car set with a VB 98 centre trailer car. I've decided at this stage just to build the VS 998. One of the advantages of doing this is that the driving trailer can be used to pick up current and if wired through to the power car will considerably improve its running.

Construction started in a similar way to the power car with the.....

....floor unit being printed out on thin card. This was then glued to a piece of 1mm mounting card...

......and five further rectangular layers of mounting card were glued underneath the ends and long narrow strips added along the sides. The ends of the rectangles were cut and filed to match the profile of the vehicle floor.

This photo shows several stages further on. The wheels are mounted in S Scale etched brass wagon W iron. One of these can rock from side to side. Pick up of electricity is by nickel silver wires soldered to the brass and bent so as to make contact on the back of the wheels. At this stage I have decided to pick up power from only one wheel on each wheel set so the contact is made on opposite side for each wheel set. The two wires are soldered to....

.....a rigid coupling bar. This is made in this way:

Test running showed a considerable improvement in the smooth running of the power car with the additional pick up points.

The VS 998 Steuerwagen is subtly different to the powered vehicle. The main differences are that:

  1. There is a driving cab at one end.

  2. Only the driver's end has three headlights with the opposite end just having two tail lights. 

  3. The driver's end has the first two window bays with bars behind the windows as it was used as a baggage compartment.

  4. The folding doors at the driver's end have four sections rather than three for the passenger doors.


Construction of the body starts with gluing the doors in position. I filed a recess in the floor/ chassis section so that the doors will be slightly recessed. Note how I've allowed an overlap of card on either side of the doors to allow other parts to be attached securely.

I've decided to modify the metal work behind the doors to make it easier to construct and more secure. I folded lengths of nickel silver strip about 3mm wide into an L ahaped and secured the metal to both the doors and the floor with epoxy resin.


To strengthen the cab doors and keep them the correct distance apart at the top a strip of 3mm wide brass was soldered to the vertical strips at the rear of the cab doors.

The cab window frames have been built up in a similar way to those on the power car using a top frame of 0.7mm diameter wire bent to the correct shape and soldered to the metal strips behind the doors. This was overlaid with a 1mm wide strip of brass  to form the top of the window frames. At the bottom a 3mm wide strip of brass was glued inside the lower cab front overlapping the top edge of the card by about 1mm. Three pieces of 2mm wide brass strip were soldered onto the upper and lower parts of the window frame.

I've now added the sides and the glazing supports in interior.


The Steuerwagen has a totally different interior layout to the powered vehicle with the two bays at the driver's end being for luggage, parcels and mail and a much smaller passenger area, although this has a toilet and additional seats at the rear of the vehicle in the area where the driver would sit if it was a powered railbus.

The Steuerwagen is now largely complete. The roof was made in exactly the same way as for the powered vehicle although I added the plastic card strip after completing the rest of the roof. so as to get a slightly neater finish.

The completed model is ready for service. There are one or two differences between the two vehicles. The roof of the Steuerwagen is bolted to the body and chassis as the fit wasn't quite as good as on the powered vehicle. I secured a large bolt to the underside of the roof and this passes through the chassis and is held in place with a washer and nut. The luggage compartment has two bars behind the windows. These are cut from brass rod and secured in place with epoxy.  I've modified the pickup on the Steuerwagen so that current is picked up off all four wheels. This makes a tremendous difference to the running of the powered vehicle and as a result I removed the pickup treadles as these were ugly and an occasionally jammed on the points as well as being a source of friction.

  The model now takes its place providing the middle of the day services leaving the six-wheeled Umbauwagen coaches to operate the school and morning and evening rush hour trains.