Truck mount vs. body mount

When upgrading couplers on locomotives to Micro-trains is it better to body or truck mount the new coupler. Or is it even possible to body mount a coupler onto a locomotive?

Mark

 

Most recent engines from Atlas, Life-Like, and Kato are body mount couplers. Older engines with truck mounted couplers like Bachmann need to be converted with special conversion kits (Micro-Trains couplers) that include new pilots to body mount the couplers. The truck mounted draft gear are cut off. You can find coupler conversion info from Micro-Trains at their web site.

 

Mark,

MTL has had coupler conversion kits that fills the pilots of open-pilot locos, like the Kato GP38/38-2 and Spectrum -8's, to turn these units into bodym-mounts or uses the standard 1015/6, and later 2001/4 couplers, in the pilot mount of locos since the original Atlas GP7 (as opposed to the re-release Classic), depending on unit.

If you are looking to replace couplers on a loco that hasn't a conversion kit available, and doesn't take the above couplers, I would still attempt a body-mount rather than truck-mount. My experience using the 1128/29/30 set of rapido replacements in trucks has been dismal to say the least. I find they simply don't work well without a LOT of fiddling.
Since most recent releases have filled pilots, you really haven't the choice of truck mount - nothing on the truck to attach to.

My personal choice is body mounting in all cases.

My 0.02 worth.

Gary.

 

Thanks for the quick replies. I know I can always count on some good information from this board. Perhaps one day I'll amass enough personal knowledge that I can provide some useful info to someone .

Mark

 

You're welcome, Mark.
Just remember to publish that amassed wisdom for those that follow.

Gary.

 

I'm not too up on the coupler lingo. I assume the pilot is basically the "box" that hold the the spring for the coupler?

How should the coupler be body mounted? In other words how far from the back of the loco should the coupler stick out? I imagine the pilot should be mounted flush with the rear of the loco. Does that sound right?

Mark

 

The term "Pilot" refers to the ends of the loco where the coupler is mounted along with MU and Brake hoses.

 

Pilot Beam is the true name for the end of the locomotive has the draft gear box attached to it. The draft gear is the attachment device the lets the coupler swing sideways, and provides a little shock control between the coupler and engine.
The draft gear should normally be flush with the side of the pilot beam. The coupler should be as close to the pilot beam as possible. Take a look at the prototype. But then the full size engines don't have to deal with the sharp curves that we use on our layouts. The sharper the curve the farther out a coupler needs be. I try to get my couplers as close to the pilots as possible. But then I have a 25 inch minimum mainline radius. There are a few places that certain engines are restricted from going, mine branches, and some city trackwork. The curves are below mainline minimum radius. The prototype has these same restrictions and it adds to operations.

 

Mark, generally if you try to push, or back, a string of cars through a turnout, or curve, you will find the truck mounted couplers will always try to derail. Truck mounted couplers were originally named "Talgo" type in France. The only reason they worked on the real trains was the fact that the curve radius was so large that each passenger car would only swing a maximum of 11 degrees to one side. The weight of these cars was suffecient to allow the wheel flanges to remain on the rails.

When cheap toy trains are made, the manufacturer could save money by designing each piece to perform more than one function, thus the cuplers made as part of the truck. Talgo will PULL alright because the force applied tends to cause the truck wheels to follow the curve. When pushed, the force is applied at the apex of the angle between the two trucks on a curve. The sharper the angle, the more the pushing truck tries to turn the pushed truch into the center of the curve causing it to jump the track and derail.

American body mounted couplers simply push against the body and have no effect on either of the trucks. Pulling also has no effect on the trucks.

One way you can tell how far your couplers have to stick out away from your engine, is to place two engines on your sharpest curve, and push then together until the engines touch eachother. You must have at least enough space between the two engines at the touching point ti insert two thicknesses of a credit card, to be safe. Now measure from the center of the one engine, to the center of the other engine. When coupled together, the pulling face line between couplers should rest at the exact center between engines and aligned with the center line of both. Where the mounting hole of each coupler falls, is where the coupler must be mounted.

In real life there may only be about 4 feet between cars, but because of the unnaturally sharp curves used on most train sets, the couplers must stick out a long ways inorder to allow the cars to swing very far. If you try to do everything strictly to scale, you will have to have a much larger layout space.

You have to 'fudge' sometimes to make it possible for your trains to run at all. For instance, one inch at N scale, is only .011" or about 4 thicknesses of paper! The flance of real train wheels is one inch long, but look at your N scale wheels, they have a flange nearly one foot long!

Real railroad couplers only swing 9 degrees off center for freight cars, and 11 degrees for passenger cars. Even with that much swing, two 86 foot dining cars can sometimes derail when trying to go through an "S" curve like in the yards through opposing turnouts. It isn't even attempted with Talgo type trucks!

 

Something that always works for me is reading the instructions. Purchase a packet of Microtrains 1015/16 couplers and proceed from there. You can also get these preassembled.

I do not see any mention of the type of model you wish to fit the couplers to! This will definately assist those eager to help you.

 

Mark

Here are some good links to photos showing the
pilot end (front or rear) on different diesels


http://espee.railfan.net/jpgs/don_jewell/don_jewell_sp-sd09-5347.jpg

http://espee.railfan.net/picindex/sd7-9_detail/rap_sd7007.html

http://espee.railfan.net/jpgs/bob_dengler_6/sp-sd45/bob_dengler_sp-sd45-8828.jpg

http://espee.railfan.net/jpgs/bob_dengler_6/sp-sd45/bob_dengler_sp-sd45-8854.jpg

http://espee.railfan.net/jpgs/charles_lange/5005b_ssw_gp30_charles_lange.jpg


eNjoy


Don B

 

There was no one particular loco I was looking for information on. More as a general rule on which type of mounting was better. I've tried the "ready made conversion kits" and wasn't too pleased with the results. Sure they worked, but as mentioned above they required a lot of fiddling. Even when I read the directions (something I don't normally do). I've bought several of the 1015/16s and like them. They're completely self contained and they don't require any "adapting" to existing equipment.

Mark

 

<blockquote>quote:</font><hr>Originally posted by mtaylor:
what about freight cars? Most of the Microtrains trucks I have seen have the couplers included. I know that they sell just the trucks as well. But how in the heck do you body mount on coal porters, autoracks, wood chipcars, well cars, etc.

Thanks<hr></blockquote>

Matt,

Coal Porters (DI type) - 1023/25, no shimming,
Autoracks - 1025 built upside down, no shimming, remove Con-Cor logo on one end first.
Woodchips cars - 1023/25, no shimming
Well Cars - depends on type. I use modified 1019's on the MDC cars.

Note, the 1015 could probably be substituted for 1023/25.

Gary.

ps, if you're still in MSP and want hands on with body mounting couplers. let me know. I'll be there mid-late Sept.

(edit note - wrong name now changed to Matt - sorry! )

[ 16 July 2001: Message edited by: Gats ]</p>

 

<blockquote>quote:</font><hr>Originally posted by Ratcals:
I'm not too up on the coupler lingo. I assume the pilot is basically the "box" that hold the the spring for the coupler?

Mark<hr></blockquote>

I am glad I am not the only one that doesn't understand all this coupler stuff. Since we are on this coupler subject. How come most engines and cars come with the plastic (rapido, do you call them) couplers. Is it a cost issue, an ease of use for kids and beginners issue, or is that just the way it is?

 

Why Rapidos? It's a defacto standard, if you wish.

Created for the European market by Arnold-Rapido back in the early days it became the norm for N Scale couplers much like the horn-hook coupler did in HO in the US and the Lima-style hook and loop in European HO, though on an international scale.
Yes, it is simpler to use and large enough to have a massive fudge factor remaining coupled. It's also inexpensive but it would have been used primarily because it was a defacto standard.
On the other hand, the MTL coupler design has recently expired it's patent and other manufacturers, such as Atlas and Kato, have jumped the band wagon to start producing 'compatible' auto/semi-auto couplers (plus the likes of Kato and Intermountain with their own static couplers) so the days of Rapido couplers on US outline RTR rolling stock is slowly coming to an end.
I'm sure Don Brown has a deeper history for those interested.

Gary.