Drawing the Pre-Rebuilt/Ex Gas Turbine UP Water Tenders

Now the model of the current UP excursion train water tenders is all finished in N scale, I turned my attention to the Pre-Rebuilt version.

My original thoughts were that this would be an easy design, as I had already drawn the main components, all that I would need to do is remove the embellishments, adjust the shape and print.  I was very wrong.  Although the two designs were built from the same tender they went through a lot of changes to get from old to new.

Here are two of the tenders in their 1955-2007 configuration.

UP Pre Rebuit Tender(Photo by Richard Wrede)

(Photo by Richard Wrede: UP 3985 In Dunsmuir,Ca. taken in 2005)

And here is one in it’s 2007-present configuration, and yes they are the same type of tender.

UP844 April 21st 6

The obvious details that where different from the new 2007-present tender such as the grab rail on the top and the chamfered ends would be fairly easy to do.  The main challenge I encountered was the actual shape if the tender body.  The Pre-Rebuilt body is wider, and longer.  Not because it is bigger inside but because the whole tender was insulated and clad with a second metal skin.  These tenders were ‘hand me downs’ form the large 8500 class Gas Turbines, this cladding covered the heating equipment and insulation which was used to heat the Bunker C fuel oil.  Remembering we are working in N scale at 1:160 I pondered about not changing the body width, that would mean all I had to do was remove the rivet detail from the sides.  But I just could not bring myself to do it so I widened and lengthened the bodies.  This in turn meant both ends had to be remodeled as the radius intersections where the curved areas meet the sides all moved.

With new body modeled in, I could then start adding the detail.  Service holes on the sides are shown below.

UP Water Tender (Turbine) Survice Holes

End pipe work and electrical ports.

UP Water Tender (Turbine) End Pipework

UP Water Tender (Turbine) End Pipework 2

And side piping.

UP Water Tender (Turbine) Side Pipework

This cars had a lot of piping and from the reference material I could find, it varied from car to car.  The two most common differences I could find, mainly with the pair UP have been using with the heritage fleet, was one had piping running over the top to the service hatch and one did not.  Here is the pipe work going to the hatch.

UP Water Tender (Turbine) Pipework Hatch

Using the reference material I was able to mostly work out where the pipes went, some just seemed to go nowhere.  Putting them in over the curved end was the trickiest part as this surface curves in two directions and the pipes don’t run in a straight line.  The piping on the model is not actually round, to give it strength it is curved on top and squared down to the body, making it into an elevated detail rather than a separate object.  This is almost impossible to see in N scale and gives the look of piping running over the body, plus it makes it strong.

Next came the top area, and this car it is covered with an open grill mesh.  This is very hard to do, not that it can’t be printed but because it would either look way too chunky or be so fragile it is unlikely to survive the cleaning and handling process.  To overcome this, the piping which runs along the side of the body between the grill mesh and the top of the body has been closed off as shown below forming a solid object.

UP Water Tender (Turbine) Solid Top

The grill has then been drawn as a recessed detail which now forms the top of the car.

The end ladders are also different on this tender, plus they had steps made from the same grill mesh.  This made them fairly quick to model, plus this time all four are the same.

UP Water Tender (Turbine) Ladder

As for the grab rails along the top, once again they would either look way too chunky or be too fragile so I have not included them in the print, however we will cover them in a later post.

The final details to add such as the tool box came last.  The trucks and chassis where used from the previous water tender model, although I couldn’t help my self and did some improvements on those too.

And here is the finished 3D model.

UP Water Tender (Turbine) Type 1 & 2

And you can get them here.

So not the quick turnaround I first considered, but I think well worth the extra effort.  The model is sized correctly and I think it will look fantastic.  In a later post I will show how it came out.

Painting and Finishing the UP Water Tenders

Now all the model errors have been sorted out and I have a successful test print of the UP’s rebuilt water tenders it was time to paint and decal them in order to finish the model.

For this I handed the model over to Bob Norris who also painted the DD35 models.  He first washed all the parts again in warm soapy water to remove any oils that may have built up on the surfaces due to people handling the model.  Once dry, he glued on the headlights and tool boxes; these can be glued on at later stage but as they are going to be the same color as the top of the body it makes sense to do it now.

Once all the glue had dried, the main body, chassis and ladders where sprayed with Humbrol’s Acrylic Sea Grey from a can.  As well as being a good primer this is also a great match for UP’s Harbor Mist Gray.

Next comes the yellow on the main body and Bob brush-painted this using Badger’s UP Armor Yellow. This paint is very thin and three coats were required to cover the primer with an even color.  For the forth and final coat Bob added a drop of PollyScale’s Signal Red into the UP Armor Yellow, this darkened the yellow to make it a perfect match to the yellow of the Kato City Of Los Angeles passenger cars.

Once the paint had dried he sprayed the whole body with Testors Glosscote; this sealed the paint and gave a nice finish.  The red lining between the gray and yellow is a red strip decal.  The other decals came from Circus City Decals & Graphics who provide a set especially for this model and can be found here.  Once the decals had been applied and set, the ladders were glued on.  The final stage was to spray the body with Testors Dullcote which removes any areas of the decals that show up shiny against the body and forms a coating to protect them.

Bob then painted the trucks with Humbrol’s Silver.  He also used a dab of this to paint the light lenses in the headlights, after which he put a drop of CA glue over the silver paint to form the actual lenses.

And here is the result

UP Water Tenders 1Several others who have purchased the kits have also sent me some pictures of the finished models and work-in-progress.

Here are Jim Reising’s UP water tenders.

Jim Reising - Water Tenders

Jim used spare handrails from a Kato Dash 9 diesel locomotive to replicate the grab rails on top.

Brian Stewart also sent some work-in-progress shots of his water tenders.

UP Water Tender 4 (Brian Stewart) UP Water Tender 3 (Brian Stewart)

Brian used brass wire to make his grab rails.

UP Water Tender 8 (Brian Stewart) UP Water Tender 7 (Brian Stewart) UP Water Tender 6 (Brian Stewart) Mark Peterson, who was also the inspiration for this project after suggesting someone make these water tenders available, used Evergreen .020″ styrene rod for his grab rails.

UP Water Tender 1 (Mark Peterson)

UP Water Tender 3 (Mark Peterson) UP Water Tender 2 (Mark Peterson)

UP Water Tender 4 (Mark Peterson)

Mark also has a video of his excursion train, complete with water tenders roiling through Hope, MN.

You can read more about Marks layout, ‘A Season In Hope’ and his adventures with the water tenders on his website here.

Mark’s original request however was for the UP water tenders as they appeared before they where rebuilt in 2007, so here is a sneak preview of what is coming next.

UP Water Tender (Turbine) Type 2

The test print for this car is in the post as I type and I’ll share with you what it looks like in a future post.

Checking the UP Water Tender 1st Print

With the 3D model of the UP re-built water tender complete and successfully ordered from Shapeways, a review of the actual model was needed to check everything was okay before making it available to all.

When the test print for the tender arrived it looked fantastic although it was hard to see all the detail due to the waxy residue left over from the print process, and the fact that the FUD material is almost transparent. This also makes it very hard to photograph but putting it onto a black background really helps. Here are all the parts for the kit laid out after a quick wash in warm water.

UP Tender Water Tender KitThe water removed a lot of the residue but it would still need to be soaked in Goo Gone for 24 hours to totally eradicate it.  At this stage the detailed parts start to become easier to see as well as the few areas which had not printed correctly.  For example, on the trucks at the bottom of the photo you can see the air cylinders and the pipes running back into the trucks; there is a gap between them that should not be there.  Looking back at the 3D model it became apparent there was an error which did not show up easily. This was fixed before releasing the model.  There were also some other minor issues with the piping, once again all traced back to the 3D model; these were also fixed.  One of the most noticeable things in this photo is the chassis which has a bow in it.  This chassis is very thin to help keep the cost of printing the model down, however is not a concern as this particular model is designed so the strength comes from the main body, which is very strong due to the multi-curved surfaces. The chassis straightens out when put into place.  Once the model is cleaned, painted and the trucks have been attached, the chassis is designed to be glued in place making a very strong, complete body.  For reference, should you receive a chassis, or any other part, that is bowed more than is shown in this picture, it can be easily be corrected using hot water as described n this previous post.

Another important part to check are the trucks to see how well the wheels fit.  This model has been designed to take Micro-trains 33″ wheel sets and, learning from experience, I don’t recommend trying to fit Atlas 33″ wheel sets as they are a lot wider and I broke one of the sides of the trucks clean off.  This was not all bad, I discovered that this material can be repaired very effectively with Loctite Gel Control super glue and it highlighted a weak spot in the trucks which was also fixed in the 3D model.  The Micro-Train wheels sets fit perfectly with a satisfying click.

Another problem I foresaw was with the ladders.  In themselves they are very small and consequently could easily be misplaced, either whilst being handled by Shapeways or by the modeller as they are cleaned ready for painting.  I didn’t want to make them a part of the main body as this would make it even harder to paint so I joined them together on a ring.

Once all the parts have been cleaned the ring can simply be cut away releasing the ladders. This is something that can be achieved only through 3D printing; no other manufacturing processes can produce parts joined together as one that don’t actually touch each other.  This also helps Shapeways guarantee they have put the right parts in the right box. Customer feedback on this has proved this works.

I found when test fitting the Micro-Trains body mount couplers a slightly bigger space would help as they where a tight fit so this was changed in the 3D model.

Once the parts had been soaked in the Goo Gone and properly cleaned they were test fitted again.  Everything fitted and worked.  Below you can see the model on a test track between a Rivarossi Challenger and a steel box car.

UP Water Tender After Goo Gone

The tool boxes on top are still loose, as are ladders, flag plates and headlights.  Once painted these can all be glued on as well as securing the chassis.

With all the updates made to the 3D model it is now released for sale and you can find it here.

The next step is painting which is done by Bob so I’ll share that with you!

Drawing the UP’s auxiliary excursion train water tenders for N Scale

The Union Pacific railroad heritage fleet currently runs two of their preserved steam locomotives on regular excursion trips and, with the very much anticipated Bigboy No. 4014 re-entering service in the next few years, the modelling of the excursion train will become even more popular. With Athearn’s new N scale Challenger and Bigboy locomotives, or even the former Rivarossi models, and the Kato ‘City of Los Angeles’ cars, this can easily be done. The one important thing missing is the extra water tenders now always used for the long trips.

Ever since the switch from steam power to diesel the supply of water along the railroad has all but dried up; often you can see local fire department filling the excursion train locomotives water tanks with their pumping equipment at stops along the way. To combat this UP have created auxiliary water tenders which hold more water than the engine’s own capacity and greatly increases the range of the excursion trips. Currently, my understanding is, the UP has four auxiliary tenders in the heritage fleet.

Here is UP 844 in Oakland, California in 2009, accompanied by one of the auxiliary tenders whilst on an excursion trip stopover.

UP844 April 21st 1 UP844 April 21st 2 UP844 April 21st 3 UP844 April 21st 4 UP844 April 21st 5 UP844 April 21st 6

These tenders started life as regular coal and water tenders for the 800-class steam engines until the engines where decommissioned due to the new diesels. However when the new 8500 class gas turbine locomotives, built by General Electric, started being used by the UP, the need for tenders to hold their bunker C fuel oil was created and the old 800-class tenders where recycled for this purpose. Because the bunker C fuel oil needed to be kept warm so it could be pumped as a fluid, the tenders were fitted with a heating system and a second metal skin for insulation and to cover the system. When the UP retired the 8500 Gas Turbines the tenders remained in storage until the heritage fleet commandeered them for the excursion trains. The heritage fleet used the tenders in this configuration until 2007 when two were rebuilt removing the heating system and the second skin. This increased the water capacity by 3000 gallons to 28,000 gallons. These two tenders were christened UPP 809 Jim Adams and UPP 814 Joe Jordan after two retired steam fitters from the UP repair shop.

I wanted to produce models of both versions of the tenders so I could replicate both periods (pre and post 2007). I decided to start with the newest incarnation and set about producing a 3D computer model.

UP Water Tender10

I used a mixture of images and drawings from the internet and books to get the correct dimensions.  There’s a 8500 gas turbine and tender at the Illinois Railway Museum and they have lots of good pictures, as do Wasatch Railroad Contractors, who did the conversion on water car UPP 814.

UP Water Tender8

Some elements were simply too small to be reproduced in N scale, such as the handrails that run along the top and up the ladders.  I decided that it would be best to add these using brass wire at a later stage.

UP Water Tender9

To make this easier to paint I separated some of the detail parts from the main model body.  The ladders, roof tool boxes, headlights and flag plates are all loose parts, as are the trucks, chassis and bolster pins.  Here are the parts laid out ready for the first test print.

UP Water Tender6

The body has been designed to take Micro-Trains body mount couplers.  The bolster pin that holds the trucks to the chassis has also been positioned off centre, unlike the prototype, so that the trucks can be removed without removing the wheel sets.

UP Water Tender7

In the next post I will show you how it came out and what improvements needed to be made before it was ready for the final print.