To paraphrase Vane Jones, "Knowledge is of little value until shared with others."

Sunday, July 14, 2013

AEFRE 49 - #4D The Flat Car with Decking

First, attach a second piece of styrene to each end of the frame to bring the end pieces of styrene up to a scale 9" thickness. When the glue has dried sand and/or dress-up the ends to make all the edges square. Remember the end pieces have to look like 2 separate pieces of lumber.

The car frame at this time with its perimeter covered with styrene is fragile. The styrene is held in place with ACC. While it's not likely to happen, the ACC brass to styrene bond can be broken. Both the brass and styrene are non-porous, very smooth surface materials. This makes the bond between the ACC and the brass or styrene less than optimal. Pressure from the side can break this bond.

Between now and when the brass car frame ends are covered in styrene handle the car frame carefully.

With the car frame in its current form, it's time to see which coupler can be used. Kadee makes a coupler with a short draft gear #806. This is the coupler of choice as the model is a small freight locomotive used to move 1-2 freight cars at a time.

The power truck was attached and car frame placed upside down on a flat surface. The draft gear from the Kadee #806 was held in place while the power truck was rotated. The draft gear prevented the power truck from being rotated more than a few degrees. The Kadee #806 flunked as the wheel flanges touched the draft gear! 

We have to go "shopping" for an appropriate coupler which will fit. After looking in the PSC catalogue,  #41237 O-On3 AAR Sharron type, standard knuckle with full working coupler looked like it would work. The hole in the coupler shank, if at a correct distance from the coupler should work out well.

These are PSC #41227 parts when the package is opened. It is a working coupler so the knuckles, lift pins and a piece of wire to hold the knuckle in place are included. Very little work is required to remove excess brass. DO NOT REMOVE BRASS FROM THE BODY OF THE LIFT PIN - ONLY REMOVE THE SPRUE.

Part of the clean-up process of a is to assemble the coupler to see if the knuckle moves plus seeing the lift pin working. If the lift pin does not fall out the bottom of the coupler there will be less problems using the coupler. If the lift pin does fall out the bottom of the coupler, when installed, a wire or chain to pull the lift pin up has to be used to hold the pin in place. I found my lift pin had to be installed from the bottom of the coupler body.

When a coupler is placed on the car frame, it looks like the coupler can be installed on the brass part of the frame. A 1-72 screw will be used to hold the coupler to the frame. This is a photo with the coupler holes drilled and tapped.

From the photo you can tell the needle beams have been glued in place.

The hole in coupler shank is too large in diameter for a 1-72 screw. Brass tubing is used to fill in the hole. The tubing is soldered in place.

After filing the couplers looked like this.

Now it's time to find out if the coupler is at the correct height. But 1st the car frame has to sit on a piece of track at the correct height. The car bolster which came with the trucks had to be shimmed with styrene.

Plus, a thin piece of brass had to be used between the truck and the body bolster.

With both trucks in place and a coupler screwed to the car frame, the coupler height can be tested vs. a Kadee coupler height gauge. The brass coupler matches up and couples to the Kadee coupler.

The coupler is slightly too high. The center line of the brass coupler should be at the same height as the center line of the Kadee coupler. Something has to be done to correct this.


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