Disguise Track Cleaning Cars (Part 1) - P2K Gondola

In this post I'm going to cover an issue that plagues many model railroads, and doubly so for operating model railroads!  Dirty Track!

A large string of gondolas and flat cars roll through Bealville at La Mesa Model Railroad Club.

The "Old Solution"

One of the long standing ways that track dirt was combated at LMRC (since I jointed in 1996) has been the use of track 'slider' cars using un-tempered Masonite, with the textured side down.  Often many modelers will drill holes, countersink, and glue a pair of nails through the Masonite pads under Athearn or other 'high sided' boxcars.

A pretty obvious "track slider" installed under NP 20107, an Accurail boxcar.

Note these pads have small knurling on one side, this actually helps accumulate the dirt and oxidation.  I've tried using smooth Masonite pads and they just skip along the top of the rails.  Cutting a few slots into them with a razor saw immediately clog when in operation.  The knurled finish seems to make a very good cleaning pad.

Over the years of operations before 'wet' track cleaning was used (always a debatable subject), the minimally 'wet' operations at LMRC resulted in pads that could almost be self-cleaning.  Evidence of this was regularly found in the form of black powder along side the rails in curves, especially at Caliente, where the rails moved on the pad, knocking excess oxidation and dirt off the pads.  This was easily vacuumed up.

After moving to 'wet' cleaning of the rails, this powder depositing stopped.  Instead we get black 'tar' catching in the frogs of the switches.  I'm interested to see if more sliders and minimal 'wet' cleaning will again return to cleaner operations and the 'dry powder' on the curves.  Time will tell.

A "New Concept" On Pads

However, I've been pushing for several years to instead use cars which already have deep carsides; such as the Daylight Triple-Unit Diner, 'fishbelly' sided flatcars and gondolas.  The trouble has always been that the nails would stick through the floors of flatcars or gondolas.

Parts for the MTH Daylight Kitchen Slider Conversion.

I started to cover the solution (SP 10250-10251-10252 Part 3 - Track Cleaning Pad) a couple of years ago with my work on a MTH Daylight Triple-Unit Diner, with the big water tank replaced with a slider pad in a 'dagger-board' trunk system (a sailboat term), which allows the pad to remain captive and float up and down on the track.

Ground-level view of SP 10259-260-261 with slider pad disguised under the right side of the kitchen unit.

The Daylight triple-unit diner does a good job of hiding the track cleaning slider pad, as seen in the photo above. 

SP 10260 with the pad catching a little bit of light.

The pad can be seen at certain angles even though it's painted black, some light will be caught on it and reveal it.

On with the Gondolas!

Starting point of  a P2K gondola and Masonite pad, rough knurled side down.

For this example I'll be showing the step-by-step installing a plain Masonite pad under a Proto2000-Walthers 52ft 6in mill gondola.  I'll be showing the same technique on several other types of cars in the future.

Checking that the Pad will Fit

I first hollowed out the underside of the P2K gondola by removing the center section of underframe, the brake cylinder mounting tab, and cutting away the crossover section of the train line pipe.

In this photo I've removed the parts listed above.  New 'bulkheads' have been installed to contain the pad.

The next step is to confirm that the pad will fit between the removed section of the underframe, in this case the pad's about 1/4" shorter than the cut away sections of the underframe.  I glued a piece of 0.020" styrene sheet, cut to fit, onto the top (smooth side) of the Masonite pad with thick ACC.  This was allowed to dry overnight.

Here's the laminated pad with the styrene top under the gondola, checking the clearances.

Next, I fabricate stripe styrene 'bulkheads' to contain the pad.  These are made out of 0.125x0.060" styrene, cut to the width of the inner edges of the sides.  Note that you'll have to cut away the trainline air pipes under these bulkheads, so that they may lay down flat on the floor of the car.  I attached the horizontal strips with ACC because of the rough detailed surface of the flooring, and the vertical strips with Tamyia liquid cement.

Forming the Containment for the Pad

The 'Trunk' was formed by two strips of 0.156x0.030" styrene cut to length between the bulkheads.  These were 'welded' in with Tamiya liquid glue down the underframe beam slots, locking them into the carbody.

Trunk installed forming a box and the pad with 'keel' glued on.

I glued a strip of 0.125x0.060" styrene on edge down the center of the pad to form the 'Keel'.  I decided for durability to keep the Keel the same length as the pad.  The operations of the pad will not be hurt by the pad sliding fore and aft in the car as it operates.  Generally the pad will stay nested to the rear during operation, one reason for the 'bulkheads' being well built and glued to the sides of the car.

Completed "Keel" (left) and "Trunk" (Right)

Notice that I cut down the corners of the bulkheads to match with the sides of the car.  Most of this will not be seen on the finished car, but it's nice not to have something hanging down that will catch the light in a bad way.

The Pad Retaining System

The next step is to make the retaining system which will keep the pad from falling out when the car is picked up.  I will use a section of 6 pound-test fishing line to secure the pad under the car body.  Note: this whole system needs to be strong enough for cleaning of the pad with a wire brush!

Guide tubes installed on the pad.

For the guides on the pad, I next cut some 3/16" long sections of 1/8" styrene tube and glued them to the top of the pad, about 1/8" in from the ends, and about 3/16" inboard from the edges of the pad.

Next, I drilled four holes in the bulkheads, approximately in-line with the tube sections on the pad.  These holes are about #65 holes, which are plenty large enough for the fishing line to be free-running.

Guide tubes installed and holes drilled.  Car masked for painting.

The car was then masked for painting of the various new cleaning components.

Painting

I used some Testors Flat Black 'rattle-can' paint to give the whole underbody between the sides and the **TOP ONLY** of the pad a coat of paint.  NOTE: Painting the BOTTOM of the pad defeats the whole reason to have it be a 'cleaning pad!'

Painting complete

Test fitting of the pad "Keel" into the "Trunk."

Rigging the Pad

The last, and sometimes trickiest step, rigging the pad under the car.

Masking removed, ready to rig!

The rigging of the fishing line is pretty simple.  It forms a loop from outside one bulkhead, through the hole, through both guides on the pad, to the hole in the bulkhead at the other end of the car.  The line is then lead across to the other side and fed to the other hole back to the other pair of guide tubes to the first bulkhead.

Fishing line fed through the bulkheads in the car and guides on the pad forming a loop.

The line is then tied off.  I used two overhand knots, which allows the knot to slide on the line, forming a noose, with which I can adjust the ride height of the pad.

Adjusting the ride height...

Make sure to adjust the ride height so that the pad will sit level on the track and can actually ride lower than the 'level' line between the wheels.  This will allow the pad to get into any 'hollows' in the trackwork and clean evenly.

Adjusting the Height

Originally my pad tended to be a bit too tight and the left end was riding up, not sitting on the rails.  A small adjustment to the line through the knot corrected the issue.  Be sure that the pad can also freely lift up 0.03-0.04" in case there are any humps in the track that the pad needs to ride over.  The last thing you want is the pad lifting one of the trucks off the rails and derailing the car!

Fishing line tied off and glued.

Once I was happy with the ride height and flexibility of the pad, I tacked the knot in place with a very small drop of ACC glue.  This will prevent the knot from sliding any more on the line, locking it in place.

Finished pad under the NKP 66031, ready for service!

Ideally the glue will not keep the line from being able to adjust in and out of the hole as the car rides on the track.  Likewise, make sure the line is not so long that the pad can become jammed under the car as it is being rerailed or the line drag and catch on trackwork while in operation.

How Obvious Is It, Really?

Let's look at this pad more on the track from 'normal viewing angles.

A slightly higher side view, the pad's there if you know to look for it...

In these shots on my workbench, the rail's not been weathered and the rest of the background isn't finished, as it would be on a layout, but everyone should be able to get the idea.

Here's a slightly higher 3/4 view.  The pad covers the side of the rail, which should be weathered dark gray or rusty anyway.

Also note, I'm using a lot of 'side lighting' on this shoot because of the black carbody.  Normally the pad does just blend into the under shadows of the car.

In this higher view, the pad really starts to blend into the shape of the 'fish-belly' side of the car.

In these three views, the effectiveness of the camouflage can be evaluated.  Having a black-bodied car also helps!

In Closing

So how many sliders could you see in a shot like this?

One of the reasons for doing this is to make a concealed cleaning pad car which will be able to operate normally during any prototype operating session or public display day and keep the layout clean.  In the LMRC Carshop Reg's for over 20 years, it is specified that each train of 30 cars MUST have a track cleaning pad car in it.  I believe over the last 15 years or so that has been left un-enforced, however with these techniques, it will not be hard to get a number of pads in operation up.  Hopefully the cleanliness of the track will improve too!

A photo of the NKP 66031 after some time running around cleaning track.  Much more than this is worth cleaning with the wire brush!

I plan to cover installation of this type of pad under several other models, to expand the locations that will be 'automatically cleaned' during normal operations.

Jason Hill

Related Articles:
SP 10250-10251-10252 (Part 3) - Track Cleaning Pad

Open Loads (Part 1) - Building a Steel Load