Engine to Tender coupling

[Eryalen]

I have just bought my first model train in 50 years (it's for my grandson, of course). The HO 4-8-4 engine has a bar with 2 holes in it and the tender has a pin to mate but it kept falling out. I bent the bar a little and that seems to work but I'm wondering if there should be a retainer or something on the pin?

[Yampa Bob]

Ery,

Of course it's for your grandson, I hope he lets you play with it too. 

First make sure the drawbar is bent so that it doesn't lift the tender front. The bar should ride normally in the center of the post with no binding.

Next, after attaching the drawbar to the post, slip on a short piece (1/8" to 3/16" long) of 1/16" inside diameter, model airplane silicone fuel tubing.  Hobby shops have the tubing, usually comes in 1 foot lengths. 

I roughen the tender post a bit so the tubing will grab better.  Easiest way is to use a 4-40 or 6-32 hex nut, whichever size works best, and cut a few shallow threads on the post.  Alternately you can roughen the post with a tiny file or coarse sandpaper.

I know you (and your grandson of course) will enjoy model railroading.

[WGL]

Eryalen,
  I'm glad you asked, because I recently got my first steamer, & I'm glad you answered, Bob.

[Yampa Bob]

Well, since both you and Erik got the answer, you two can split my customary fee. Just kidding. 

I tried various methods, but the tubing seemed the easiest and least noticeable. Buy a foot of it, so you'll have enough for 96 locomotives.    Like Frito-Lay says, "You can't stop at just one".

[rogertra]

Bob.

Let me understand this.

You put the tube over the drawbar pin so that the drawbar cannot slide up and down the drawbar pin?

I would think that this would lead to derailment of the tender's leading truck as the stiff drawbar would tend to lift the front of the tender.  All I do is bend the drawbar so that it cannot slip past the bottom of the drawbar pin and this still lets the drawbaw slide up and down the pin.

[Yampa Bob]

The tube barely goes onto the long pin, so there is plenty of room for the bar to slide up and down as required for track conditions.  Since the bar is "floating" near the center of the pin, it will not lift the tender.

Best way is just to try it and adjust the tubing.  Since my track is all flat, I position the tubing a bit higher on the post, have never had a derail problem with any of my Connies. 

[rogertra]

OK Bob, now I understand.   

[Yampa Bob]

If the shop doesn't have the 1/16" ID tubing, here is another method that only requires a pair of scissors.

Leave the pin smooth, but clean it with alcohol. Cut a strip of sticky black electrical tape 1/8" to 3/16" wide about 3" long.  Attach the bar and hold it up a bit away from the pin end. Tightly wrap the tape around the pin end until large enough to retain the bar, cut off any excess.

Tru-Value hardware has the tape, about 50 cents a roll, very stretchy and really sticks tight. 

[pdlethbridge]

how about using some 1/16 shrink tube, or 3/32

[Yampa Bob]

1/16" shrink tube might work if it's stretchy and thick enough, just don't apply any heat which might melt the pin.  It might require a thin shim washer above the tubing. 3/32" is too big without heating.  You're on your own with this one. 

My Roundhose locos have a flexible drawbar. It flexes up/down and twists easily but doesn't stretch, held to both loco and tender with a screw and washer, very nice setup, haven't had a single derail.