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Any narrow gauge news/ coupler bounce is prototypical

roundbell@...
 

If you have actually worked on real railroad cars you realize that "coupler bounce" happens on the real cars. The springing in the coupler draft gear is used to absorb coupling impact both in and out. Each car coupling has some give both in the jaws and in the springs that mount the coupler in the body. The 714 have too much give ( Bounce ) but to be correct models of real couplers they do need some bounce but looking at the 715 in a model looks like it will have no more "bounce" than the real couplers have and if you have the point at the front of the coupler box pin the coupler will center. I think the new coupler will satisfy the people who object to the "bounce" and we will have to see how difficult it is to install in various models.  LocoDoc


-----Original Message-----
From: Mark Kasprowicz <marowicz@...>
To: HOn3 <HOn3@groups.io>
Sent: Thu, Jul 18, 2019 11:46 pm
Subject: Re: [HOn3] Any narrow gauge news from the NMRA National Convention

That's a great shame. I had hoped that this would a) retro fit the 714 as a drop in replacement and b) eliminate the 'bounce' altogether. The potential for sales to RailLine and BS owners must surely have been a consideration. But if the conversion involves hacking away bits of an already perferctly good draft box, then I'm afraid I'm not interested.

Lost opportunity IMHO

Mark K

ftgcss
 

Coupler "bounce" as you describe it only happens on cars with cushioned drawbars (auto racks, lumber racks and some box cars for example) narrow gauge cars of 50's and previous did not have cushioned drawbars and therefore had no "bounce".  Additionally even with cushioned drawbars once the slack is stretched the couplers stay pulled out unlike Kadees whose springs can actually pull the cars back together and make the train look like a slinky going down the track.

Scott

Earl Knoob
 

One must also understand how the draft (pulling) and buff (pushing) forces act on the prototype.  When pulling up hill, the slack is stretched.  It is going down grade where it gets interesting.  The slack will run in to the engine and stay that way until the air brakes are applied and the train then stretches the slack.  In the days of steam, you did all you could to keep the slack stretched out.  The problem with out HOn3 models is the cars don't roll free enough to keep the train bunched against the engine.  If there was enough drag in the cars, they could be kept stretched going down grade, but then the locomotives couldn't pull anything up grade.  Back in the dark ages of DC operation I had a couple of cabooses set up with rear marker lights and rail wipers that provided power for lamps.  With the wipers down, I almost had to double head the caboose up grades.  But going down grade, it anchored the train nicely and kept it stretched.  The solution was to rig up a way for the wiper to be pulled up off the rail when running up hill.  The wiper could be manipulated with a tooth pick when the train was stopped.  Kinda crude, but it worked and all trains had to stop at the top of the grades for an "airbrake inspection" before starting down.


From: HOn3@groups.io <HOn3@groups.io> on behalf of ftgcss <ftgc@...>
Sent: Friday, July 19, 2019 10:45 AM
To: HOn3@groups.io
Subject: Re: [HOn3] Any narrow gauge news/ coupler bounce is prototypical
 
Coupler "bounce" as you describe it only happens on cars with cushioned drawbars (auto racks, lumber racks and some box cars for example) narrow gauge cars of 50's and previous did not have cushioned drawbars and therefore had no "bounce".  Additionally even with cushioned drawbars once the slack is stretched the couplers stay pulled out unlike Kadees whose springs can actually pull the cars back together and make the train look like a slinky going down the track.

Scott