Model Railroading > Putting a Lid on it...to Stay

Friction fit pins to hold on coupler box lids and trucks are generally a bad idea that will fail sooner or later, and need to be replaced with screws. I had two such projects sitting on my work bench this week. First up is a Walthers 33K Gal tankcar kit that I built more than two decades ago. The coupler box lids was being held with some glue, but that failed on one end. The car was in need of some other upgrades, but getting screws in the coupler box was the main focus here. The Kadee Tap and Drill sets are great, and I have them in the 2-56, 0-80 and 00-90 sizes. They come with the tap, tap drill and clearance drill bits, as well as some screws. You will need a pin vise to use them like the one I have shown. An xacto knife and a mini-awl are very helpful too.
 First I take off the pin on the couple box lid with the xacto knife and then use the mini-awl to depress a divot into the plastic where the pin was. This helps center the drill and keeps it from wandering. I drill out the hole with the clearance bit so the screw will pass through the lid. Next drill out the hole in the coupler box post with the tap drill (for the love of god, DO NOT drill it out with the clearance bit). Finally you can tap that hole. Be VERY gentle as it's very easy to strip out the hole with the tap hits the bottom. Use only light pressure to twist the tap, and stop when the resistance increases. I had some 0-80 screws that were black and had a phillips head that I used on this car to blend in better. The glue on the bottom of the lid was holding a cut lever that is not shown, but will be reinstalled.
 1. Walthers 33K Gal Tankcar kit built over 2 decades ago featured a press fit coupler box lid held in place with some glue that failed.

2. Kadee #780 drill and tap set for 0-80 screws. It comes with the 0-80 tap, #55 tap drill and #52 clearance drill, as well as some 0-80 x 1/8" screws.

3. After slicing off the plastic pin with an Xacto knife, I'm using my mini-awl to push a divot into the plastic where the pin was. This keeps the clearance bit from wandering around and drilling a off-center hole in the coupler box lid.

Ted Curphey
Ontario, OR

---

---

---

4. This is a great pin vise that has a rotating knob to allow more force when drilling. Inside are two reversible chucks for four different shaft size ranges that can handle anything from 1/8" down to .005"

5. 0-80 screw installed. Just going to reinstall the cut levers and some other details, and painting prior to installing the trucks.

6. The car is back in service now. One key upgrade I made when building this car a couple decades ago after bad experiences with earlier Walthers Tankcar Kits. I replaced the corner posts on the platform handrails with Athearn Locomotive Handrail Stanchions that are inserted into holes drilled into the body of the car. That made them far more robust and not so easily damaged.

Ted Curphey
Ontario, OR

---

---

---

Next up is a Atlas PS-2 2-bay cement hopper. Older Atlas models are notorious for truck pins that easily fall out, as well as the coupler box issues. Here I've drilled and tapped the truck mount hole for a brass 2-56 screw, but used one of the Kadee 0-80 screws to hold on the coupler box lid.

7. Atlas PS-2 2-bay covered hopper that had a push pin holding the truck on. The truck pin hole is already drilled and tapped for the 2-56 brass screw. The coupler box will be drilled and tapped for the Kadee 0-80 screws.

8. All done installing screws on this Atlas PS-2 2-bay cement hopper. Now to add some detail and heavy weathering.

Ted Curphey
Ontario, OR

---

---

Nice post!  

And these friction pin couplers always seemed to fail at the most in-opportune times...

Kirk Out

sawdust Wrote:
-------------------------------------------------------
> Nice post!  
>
> And these friction pin couplers always seemed to
> fail at the most in-opportune times...
>
> Kirk Out

Thanks!

Ted Curphey
Ontario, OR