HO Scale Model Railroad Freight Car Construction Tips:

My constantly sputtering efforts at model railroading


Intermountain Railway Company Cylindrical 4-Bay Covered Hopper

IMHO, a very nice car, but the instructions omit a few things.  This tip sheet is intended to be used along with the Intermountain instruction sheet.


Drill #76 in the following locations:

Roofwalk grabiron holes.

Grabiron holes on side ends of body and on lower edges of cage ends. Instructions call for a #77, but that's a bit tight.   Be sure to remove the flash from the backside of the holes so that the cag ends sit properly on the platform ends.

Drill #71 in the small holes on the "B" end deck of the carbody. These are for the brake system mounts. There are holes on each end for the brake pipe assembly to be mounted on the bottom side of the deck--do not drill these through.

Drill #71 in all of the holes for the roofwalk supports, both along the topsides of the body and on the roof. The instructions call for a #67, much too big.

Drill #63 in all of the hinge eyelet holes on the roof. The instructions call for a Drill #61, but that's a bit too big.

Run an Exacto blade (#11 is good) once or twice around the two larger (not largest) holes on the "B" end deck for the parts (g7) and (g3).  The largest hole, as seen from the bottom is for the coupler pocket cover stem.

CONSTRUCTION: [STEP ] refers to the same steps listed in the Intermountain instructions.


STEP 1. Cut the large sprue from the top of the body before inserting the dividers.  An Exacto saw would help.

STEP 2. I sometimes use Kadee #5 coupler pockets instead of the Intermountain pockets. However, that means that the boxes will have to be painted to match the body.  Cut off the ears from the Kadees--this will provide more clearance for the truck assemblies to swing. I install the pockets near the end of construction, usually in STEP 8.

STEP 3. When you install the roof, make certain that the holes for the roofwalk supports on both parts line up straight with each other.

STEP 4. Mount the triple valve (g6) to its stand (g5), then mount the stand to the deck. Although the instructions never mention it except in the diagram, the 3 long train line parts (g) and (f) are part of the brake system. However, I usually install these near the end, in STEP 10.

STEP 6. Make sure that all of the roofwalk supports are straight up and down. Cut off each pin on the tops of the 4 end roofwalk supports before you install them.  ALTERNATE TECHNIQUE: cut the top pins off of the four end supports and install them (the supports, not the top pins) on the carbody. Install all of the rest of the supports on side 1. For side 2, mount the supports on the underside of the roofwalk, all but the two end-supports, which are already on the carbody. When everybody is dry, apply glue to all of the top holes on side 2 and to the top pins on side 1. Line up the horizontal pins of side 2 in their holes, apply a small amount of sideways pressure to snap the supports into the top holes.  Then bring the far side down on top of the side 1 supports. With any luck, most or all of the pins on side 1 will line up in their holes on the underside of the roofwalk. Then apply glue to the four end supports and hold in place until set.

STEP 7. The thin vertical strut (the part that butts up against the cage end to form an "L" bar) on each side ladder needs to have a very small notch cut into the top.  If you look closely at the side of the cage end you will see a small square at the top.  The notch should fit around that small square.

STEP 10. After you have installed the hopper bottoms, clip off about 1/32"to 1/16" of each end of the long train lines (g) and 2 (f). One of the (f) lines has pins on the bottoms and indentations on the tops of the mounts to accept the second (f) train line. Both parts (f) have 6 mounts. Install all three, making sure that the ends are tucked up into the corners next to the bolsters so that they are out of the way of the trucks.