Last Updated: 22 August 2003
BACKGROUND:
According to Dan Valentine of New England Rail Service (Rail Model Journal - March, 1998), the Southern Pacific, Pennsylvania, and New Haven railroads were primary users of ice-activated air-conditioning systems. He reasons that SP had an existing huge investment in ice production for its PFE reefer fleet and, similarly, Pennsy had a controlling interest in Fruit Growers Express (FGE). In addition, at the time air-conditioning systems were introduced, the ice system was the most reliable, and lines like the Pennsy and the New Haven that heavily catered to the passenger trade were most likely to benefit from early introduction of air-conditioned cars. This perhaps explains why so many variations of Pennsy's extensive P-70 coach fleet showed evidence of ice-activated air-conditioning systems. If you buy a Spectrum P-70 coach or combine, however, you'll quickly note that there are no tell-tale ice bunkers underneath the cars that would indicate an ice a/c system. We can fix that, however, with a little additional time and attention.
Before we add the distinctive ice bunkers, however, there are some other changes you might want to consider making to improve the appearance and operation of your Spectrum coach or combine.
BASIC OPERATIONAL IMPROVEMENTS:
1. You may want to alter the talgo-like coupler mechanism that comes with the Spectrum cars unless you consistently use talgo-type couplers (i.e., couplers whose draft gear box swings as a unit with the trucks) on your passenger cars. The truck kingpin on the Spectrum cars is directly connected to a kingpin on the draft gear box, forcing the coupler to pivot in the same direction as the track curvature. Coupled to a car with body-mounted couplers, the couplers may fight each other, causing one or both cars to derail. It’s generally best to consistently body-mount or talgo-mount the couplers on your passenger cars.
2. Remove the roof (according to the directions that come with the car) and pry and nip the offending coupler linkage. Note: It isn't good enough to simply detach the actuating lever from the draft-gear box because the lever will flop around and jam, causing a derailment. Remove the lever entirely and build a new draft-gear box.
3. If you're inclined to use Kadee couplers, use a Kadee draft-gear box. You'll need to add a shim of .090 (3/64") styrene, however, to maintain the correct coupler height relative to the height of the car floor from the rails. Jay Bee Products specifically makes coupler mounting pad kits for passenger cars including Spectrum cars (#118).
1. If you bought a combine (combination coach/baggage car), you may find that the seats are "backwards." Generally, a combine was placed in one of three probably locations, depending upon its function:
At any rate, the baggage portion of the car would invariably face the front of the train, and the coach portion would be to the rear -meaning that the seats should be facing the baggage portion of the car.
2. Coaches and combines should have lavatories. That detail can be approximated by building the walls out of styrene or cardboard, painting them, and gluing them in place with a 1/8-inch square piece of wood or styrene at the base of each wall for stability. These lavatory walls will become more visible of car lighting is added.


4. You may need to renumber the car, especially if you're trying to model a specific car (and Pennsy had a multitude of variations on the P-70 theme). Use a fiberglass brush or "Chameleon" paint stripper to remove the number without damaging the paint underneath. Then decal the car with the correct number.
THE ICE AIR-CONDITIONING SYSTEM:
1. The ice bunkers are the most noticeable detail that needs to be added. We'll use New England Rail Service Inc's Kit #252 Pullman double ice bunker and a companion single-bunker kit to give us the facing and sides (with latch) of the bunker. However, to form the distinctive “belly” shape that appears to extend the full width of the car, we’ll create that shape out of wood. Reportedly, Bethlehem Car Works manufactures the complete ice bunker, but we’ll use just the facings from the NERS kits.
2. Form the basic shape (see diagram) out of 2 x 3 x ½ inch piece of wood - I used poplar because it's a hard wood that can be sanded precisely, keeps its shape and doesn't warp. A Home Depot kind of store should have short lengths of poplar for cabinet work.
3. You 'II need to make a lengthwise cut to reduce the 3-inch width to 8½ scale feet. A sabre saw is probably the best bet for this cut. Dress up the sawn side with a sanding block, belt or disc. Then cut this piece to lengths of 9, 16, and 18½ feet for double, triple, and quad bunkers. Sooner or later you'll need these pieces, and it's nice to have them already cut. Valentine says he thinks triple bunkers were most common, but the Pennsy photos I've see clearly show some cars with quads.
4. It doesn't hurt to form a template to form the cross-section of the bunker, especially if you're planning to build a number of cars with ice a/c systems. See the drawing for the template (Figure 1), then replicate it in cardboard or styrene to allow you to mark the wood for cutting and sanding. The wood shape was cut to 8½ feet wide, but the facings will add the final 6 inches to make the required 9-foot exterior width.

5. Using the template to mark the bunker cross-section, carve, saw or sand a bevel into the lower edge of both sides of the bunker to give it the belly you see in the photos. I found a belt or disk sander makes quick work of this task (I'd hate to have to do it by hand!).
6. Carve out a 1/16-inch-deep channel, 3/8-inch wide (dimensions in Figure 2 are given in scale feet)to clear the car's center sill- that way the top of the bunker will be snug to the lower edge of the car side.

7. Once you've cut and sanded the dimensions to your satisfaction, seal the wood with sanding sealer. Then start by gluing the bunker facings on the outsides. Next, glue the end facings (with latches) to align with the outside facings. That will leave you with an odd shape that needs to be custom-cut from sheet styrene. Use .030 (1/32- inch) styrene to match the thickness of the facings. You can use the cross-section template to guide the cut.
8. Now you should be ready to paint the assembly and glue it in place. Follow your photo, but you'll have to rearrange some underbody details from the original Spectrum car and probably add a missing detail or two.
9. Don’t forget the roof details as well. You may need to eliminate some of the vents that came with the Spectrum car; if you do, just pull them out (If you do it gently, you can reuse them on another car) and fill the holes with Squadron Green putty.

PAINTING AND FINISHING THE CARS:
1. Pennsy roofs may have been black, but they rarely look that way in color photos unless they're fresh out of the shops. You can spray the roof, trucks and underframe flat black or Engine Black to start with, but then come back and overspray with Roof Brown or Tie Brown in a light airbrush coat.

2. Brush-paint the car ends and diaphragms to match the car's color. Don't forget the handrails, too.
3. Dry-brush a coat of rust on the striker plates and couplers.

4. Brush wheel-backs, wheel-webs and axles Grimy Black.
5. Dulcote the sides, underframe and roof, but mask windows before doing this (I know it's tedious, but even Pennsy tried to keep the windows washed on their long-distance cars -if you're modeling the New Haven or the Long Island, however, that's another story!).
6. Apply some artists' pastel chaIk-dust (dirt colors of course) to the Dulcoted surfaces.
7. When all the painting, Dulcoting and dusting is done, clean up the wheel treads and electrical contact points, and dress-file the knuckle faces for smooth operation. You should wind up with a unique variation of the basic Spectrum car. Bachmann has made a superlative model to begin with. and my guess is you'll wind up with an even better one.
JOHN E. HAMMOND, Tidewater Division, N.M.R.A., August 16, 2003
Photos by Max R. Robbins, Jr.
References:
Rail Model Journal --- October, 1997 --- Modeling Air Conditioning (Part 1)
Rail Model Journal --- February, 1998 --- Modeling Air Conditioning (Part II)
Rail Model Journal --- March. 1998 --- Modeling Air Conditioning (Part III)
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