by Jeff Eggert
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Stamping Brass Ribs - Jigs & Demonstration
This How-To shows how the indented ribs found on some GATC covered hoppers were reproduced in HO scale from .001" thick brass sheet. I call them 100 Second Ribs, because in the demonstration video at the end, that is how long it takes to make one rib from brass sheet to finished product, ready to attach to the car side.
Go to the primary How-To - Scratch-Building a GATC 4700 cuft Grain Car

The tools to make the ribs. In counter-clockwise order starting with the modified scissors: Trimming Scissors, Rib Mold, Rib Die, Rib Gloves, Rib Bender, Trimming Holder.
Ribs started as a sheet of .001" thick brass sheet. The sheet was cut into oversized strips. Rib Mold shown also.
Rib Mold. Brass angle used to set the width. Round styrene rod in between for the valley in the face of the rib. Slope at the top of rib is in there at the brass cross-over piece.
Rib Mold with brass sheet ready. Rib Die is a .250" square styrene bar outfitted with a master rib made from styrene. Due to the way the brass is pressed and the thickness of the brass, this master does not have to be perfect. Rib length set by markings on the Rib Mold.
Brass stamping ready to be trimmed. The rib definition is very visible.
The trick to trimming the flash from the ribs is not bending or curling what you want to keep. A bend piece of tin was fashioned to act as a clamp with a styrene spacing limiter to hold the rib in place. Thin styrene strips were added to give the correct "hat brim" width for the ribs.
The Trimming Scissors, which is a $7 craft scissors, has an addition of a piece of styrene, set to fit inside the back of the rib. This keeps one cutting surface tight against the back of the rib hat brim while allowing the other cutting surface to trim along the rib length. This keeps the rib unstressed, curling the trimmings. After trimming one side the Trimming Scissors is removed and used again on the other side.
This view shows the Trimming Holder with one side of a rib trimmed.
A finished rib.
Since I am modeling a dented car, one side's worth of ribs had to be dented. Each rib is marked on where it needed to be bent, and then it is placed in the Rib Bender, matching the bend line with the valley of the Rib Bender.
The Rib Gloves are used bend the ribs and to prevent the ribs from becoming all bent up and mangled looking while being bent against their strong axis. Being so thin, the ribs were more fragile than they look when a side or twisting load was applied.
A bent rib.  Notice how the hat brim actually curves.
To add the ribs to the car side, super glue was laid on the rib guide and a rib carefully set into place. Once firmly where the rib belonged, a Rib Glove was used to snuggly adhere the ribs onto the rib guides. The rib sides needed extra help squaring up, the Rib Glove did the trick. The pre-laid rib guides are explained in the primary How-To.
Ribs attached to car.

Demonstration Video of "100 Second Ribs"
This video show how one rib was created in 100 seconds from flat brass sheet to finished rib. There is no narration and minimal background sound.

They say pictures are worth a 1000 words.  Well, then a video which is really whole bunch of photos, must be worth a 1000 pictures. Mathematically speaking that means a video is worth 1,000,000 words!