Coupling

I'm having a coupling problem I hope someone can help with. I'm building an activity for KHP2; using the KHP2 stock, I'm uncoupling the caboose from the train, placing the remainder of the train on a siding, picking up a static consist of loaded sulfur hoppers (also KHP2 stock), and backing into the caboose to pick it up.The problem is, I can't get the caboose to re-couple. I've tried all speeds from 1 mph through 7 mph, and all that happens is the caboose is pushed backwards. I can't get the darned thing to hook up.I've looked at the coupling settings in the .wag file, but don't see anything different from coupling settings on other cars that couple just fine.Any suggestions?Thanks,MC

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

RE: Coupling, frankgi, Nov-14-04, 08:44 PM, (1) RE: Coupling, seern, Nov-14-04, 10:47 PM, (2) RE: Coupling, seern, Nov-14-04, 10:59 PM, (3) RE: Coupling, MasterChief, Nov-16-04, 09:04 AM, (4) RE: Coupling, jtsdadinaz, Nov-16-04, 02:39 PM, (5) RE: Coupling, frankgi, Nov-17-04, 05:11 AM, (6) RE: Coupling, frankgi, Nov-17-04, 05:14 AM, (7) RE: Coupling, MasterChief, Nov-17-04, 09:07 AM, (8) RE: Coupling, frankgi, Nov-17-04, 09:58 PM, (9) RE: Coupling, leisure, Nov-18-04, 04:28 AM, (10) RE: Coupling, charlie, Nov-18-04, 06:10 AM, (11) RE: Coupling, MasterChief, Nov-19-04, 09:07 AM, (12) RE: Coupling, jtsdadinaz, Nov-19-04, 07:31 PM, (13) RE: Coupling, MasterChief, Nov-20-04, 09:32 AM, (14)

Conferences | Topics | Previous Topic | Next Topic

Do all the air brakes go haywire when you try to couple? It may be a bounding box problem on the caboose. Check out "Bounding Box Edit" in the FL. Its worth it!

FrankG
NJ
MP 9: Vineland Secondary
http://www.sjrail.com/

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

If he is using the cab that comes with KHP2, there should not be a bb issue. In my activities for KHP2 I have not required the cab to be uncoupled and picked up again. I could fire up the route and try to drop and reattach the cab.

Sharon Evans
Glen Allen, Virginia
Activities are what makes MSTS run.

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Ok, I just went in and had no problems dropping then picking up the cab. Now to check if it is a bb issue press ctrl + to turn on visable bb. Now look at the cab and the car just ahead. The red boxes that you see should either just touch or not touch at all. If they overlap then you will never get a couple.

Sharon Evans
Glen Allen, Virginia
Activities are what makes MSTS run.

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

LAST EDITED ON Nov-16-04 AT 09:07 AM (EST)

>If he is using the cab that comes with KHP2, there should
>not be a bb issue. Agreed; I took a look at the bounding boxes, all looks fine (see below). Kind of hard to tell from my picture, but about half the coupler sticks out past the bb on both cars. When I try to couple, the bb's do not touch before the couplings bottom out and the caboose begins being pushed.Could it be something else? I've even tried setting the hand brakes on the caboose to prevent it from rolling (as much), but to no avail.Thanks,MC

Attachments

http://www.train-sim.com/dcforum/User_files/419a08ca567cc9a5.jpg

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

If that is the way it really looks, the length is wrong.

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

I would shorten the lenghth of the bb on the caboose by maybe .040. Bring the bb back to the vertical ladder on the caboose.

FrankG
NJ
MP 9: Vineland Secondary
http://www.sjrail.com/

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Bounding Box Edit in the FL......orhttp://www.train-sim.com/howto/boundbox.htm

FrankG
NJ
MP 9: Vineland Secondary
http://www.sjrail.com/

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

LAST EDITED ON Nov-17-04 AT 09:08 AM (EST)

Thanks - I've played a little with BoundingBox Edit in the past...but I don't really know what I'm doing. I'll try shortening things a little, both on the caboose as well as on the sulfur hopper.One more thing I noticed in fiddling around with this, is that the lower limit (height) of the box on the caboose is below ground level. Which value in BBEdit do I need to change to correct this?Also, what does the "inertia tensor" value do?MC

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>One more thing I noticed in fiddling around with this, is that the >lower limit (height) of the box on the caboose is below ground >level. Which value in BBEdit do I need to change to correct this?>Also, what does the "inertia tensor" value do?MC,
Dont really know either, but I just try and remove all the "red" values (out of range) and replace them with "in range" values. There is a button labeled "Fix" that usually does the trick.
I hope this helps.
Drive safe!

FrankG
NJ
MP 9: Vineland Secondary
http://www.sjrail.com/

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Hi,As jtsdadinaz said in #5 the length is wrong.
The bb seems to be allright. The length in the Inertia Tensor is too long. Either the caboose or the other wagon.
compare the length from the bb's and the inertia Tensor's. If you see that the Inertia Tensor is far longer then the bb, shorten the length in that Inertia Tensor. Good luck, Jan.

Steam is hot

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>Also, what does the "inertia tensor" value do? You can find many treatments if the InertiaTensor on the net. If you already know how to resolve (either graphically or mathematically) vector forces, then the following link is written in language such that it might begin to make some sense to most folks. If the math gets in the way, ignore the math bits and just read what he says.http://baba.astro.cornell.edu/inertiatensor.pdfIn the statement "InertiaTensor ( Box (3m 3.5m 17.7m) )", the Box part is simply the size of the object for which we need to resolve, about all three axes, the angular or rotational momentum at any instant in time.In the dictionary definition, if in fact the "coordinates of an arbitrary point in space" is the object Center of Gravity, you can immediately recognize the implications of misplacing it. Or you might choose to misplace it on purpose to tailor stability to your needs. You could even assume that this is the one best reason for holding "InertiaTensor" separate and distinct from "Size" in the wag file.You can think of the IT "Box" as just a distribution of mass about a point of rotation. The point of rotation is, by definition, the CoG.The IT is only useful for describing the properties of a mass during rotation about the CoG, specifically the angular momentum. If you think about the ease or difficulty of changing the direction of an F-15 in roll, pitch or yaw, then you'll have it. A first order effect for a high performance aircraft, a third order effect for a train.Increasing the size of the Box to the max allowable (no bigger than "Size"!) will make it more difficult to turn or roll.When coming off a tangent into a curve, an actual torque has to be applied to the distributed mass in order to give it some rotational momentum to force it to rotate (turn). The Inertia Tensor allows the calculation of the Newton-meters (torque) required to get the thing rotating. Once rotating, it wants to continue to do this, so coming off the curve you have to do the same thing all over again in the opposite direction.Torque is just the result of a force applied to the end if a lever arm. Our "lever" is the size if the Box & our "handles" are the wheel flanges; bigger Box requires more torque & vice versa.Rotational inertia is exactly analogous to linear momentum. This is just another application of Newton's First Law: "An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force."regards,
charlie

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Thanks to all; I shortened the bb on the caboose as well as the sulfur hopper by about .8, and coupling is now possible, although not 100%. I may need to play with lengths a little more.MC

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Which Caboose and Which hopper?

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

KHP2_Caboose and KHP2_SulfurLD.

Alert | IP

[ Home | MSTS Forum | MSTS FAQ | How To... | File Library ] Copyright © 2004 by Nels Anderson. All Rights Reserved.