Ah. My apologies John in not thanking you back in the other thread. I would have hoped I would have at least clicked the thank button but perhaps I was so caught up in the construction that I completely overlooked in. Regardless, it was no excuse so I’ll be sure not to let that happen again in the future.
For those curious of a side view of the area that had the problem, it can be seen right here though in this video the train is going the other way, and the other tracks that have been added since then were missing.
As soon as I get the steel cut, I’ll be running the train that was a problem again, with a net, or something and me standing there. I’ll update here with the results once I do. I suspect the problem will go away.
Nicolas, I’ve emailed you my suggestions… seems that it’s hard to be constructive here on the forum some times.
Greg
Hello Nick the point to my post was if you follow Ted’s recommendation you will have the best luck of not having derailments and be able to pull longer trains. with his recommendations i have been able pull 49 cars up 4 plus % with curves also. Some people just don’t get it.
Richard
Sorry Richard, I misread your post earlier and missed that you stated you did mods per Ted.
Can’t get any better endorsement than running things at shows were everything can go wrong.
On car weight, I use the 1:29 equivalent of a light load of the prototype as a starting point. For cars like box cars, even increasing the weight to the model equivalent of the unloaded weight makes a huge difference. It’s clear to me that the intermodals are just too light stock.
Regards, Greg
Richard said:
Hello Nick the point to my post was if you follow Ted’s recommendation you will have the best luck of not having derailments and be able to pull longer trains. with his recommendations i have been able pull 49 cars up 4 plus % with curves also. Some people just don’t get it.
Richard
What radius were there curves you ran with? Thanks
Removed Duplicate Post
I know this has been posted before, but take the prototype unladen weight, and since weight is related a 3 dimensional volume you divide the prototype weight of a car by the cube of 29 (in this case) 29**3 = 24389
Unladen weight of a typical 50-60 foot boxcar (reference UP site: https://www.up.com/customers/all/equipment/descriptions/boxcars/index.htm) is about 120,000 pounds for their lightest ones, divide that by 24389 and you get 4.92 pounds… that is unladen. And that is the lower end of the weight scale. Fully loaded the same car scales out to 10.7 pounds.
Your typical double stack intermodal (reference GBX https://www.gbrx.com/manufacturing/north-america-rail/double-stack-cars/all-purpose-double-stack-car/) unladen is 54,000 pounds, which comes out to 2.2 pounds, but fully laden comes to 9 pounds.
Clearly the intermodal is designed to have all the weight in the cargo, but for a 60 foot car, 2 pounds is awfully light, 3.5 is as light as I run my 40’ box cars, so 5 pounds makes sense.
I know someone will come up and tell me the laws of physics do not hold for our trains, but do the math on the locos too… I think you will be surprised at the parallels of properly weighted models and this calculation.
Greg
When I started in large scale, I asked around about the recommended car weight. Yes, I modeled in HO and N before I became a gauge 1 modeler. In HO and N there is a chart of NMRA recommended weights for cars. But no such recommendation seams to exist for large scale. Working back from a prototye’s weight seams to be the most reasonable way of going about it.
Also, it is (usually) common railroad practice to put the heavier cars toward the front, and the lighter cars toward the rear. This tends to prevent stringlineing and popping the lighter cars off the rails when the breaks are applied.
This past week I finally had the weights put in place so I was able to test out the changes.
I decided to put the steel plates in the containers. The bottom containers of each car have a steel plate in them that is the length of the container and the size per the article on Greg’s site. I wrapped each plate in some shipping foam that I had.
During the first run, I noticed the cars were leaning quite a bit. I quickly realized I didn’t take effort to put the plates in the center of the containers so I stopped and adjusted each one. At some point I’ll need to add spacers so that they cannot slide. They shouldn’t hopefully slide just from moving in the cars, but if I lift them off and move em around the metal weight could shift back to one side.
The runs after adjusting the weights seemed to go fine. The cars still leaned in at times when stopping with the container cars over curves. Starting back up would also cause them to lean just slightly. Made it much more clear to me what had happened during the accident. The added weight also likely has increased the effect since the container cars themselves are heavier too.
I did tests with two sets of 5 in which 4 cars were strung together with shared trucks and 6 were strung together with shared trucks. I also had 2 individual containers on there. I also tried a configuration very similar to what appears in the video. I moved them all over the railroad stopping at places where I feel the cars would try to string line. Everything seemed good, except for an occasional slight lean when starting up.
.
A single SD70 can no longer really pull 10 of them up the grades I have like it used to. This is understandable with the added weight. Two SD70’s had no issue pulling the load as seen in the video.
As a side note: one of the two SD70’s I ran had the battery moved to the fuel tank with the original weight put back over the trucks. At one point I had the lighter engine pulling the set of 4 cars and the heavier engine pulling the set of 6 + a single. They were running on the same track a distance apart but still paired with my remote as a consist. I noticed the heavier engine pulling more weight was going noticeable faster. The added weight to the engine must have made a notable difference in the traction of its wheels. The lighter engine is “front” heavy. I am guessing the battery does not weight as much as the led weight.
If it’s not necessary to remove the weights, try using double sided tape to hold them in place.
Hmm. Interesting. Because I wrapped them all in a packaging foam, I am not sure how well the tape will hold to it. I’ll have to play with that idea and see if I can come up with something that works or remove the packaging foam.
Paul Burch said:
Must be track or radius. I have been running a 15 car set for years without problems.
X 2 as I’ve had good success running mine also. Later RJD
Nicolas Teeuwen said:
Hmm. Interesting. Because I wrapped them all in a packaging foam, I am not sure how well the tape will hold to it. I’ll have to play with that idea and see if I can come up with something that works or remove the packaging foam.
Guys have been using the double sided tape for years. You won’t need the foam if you secure both ends, no rattle.
You want the weight as low as you can. Metal wheels add a lot too, if you’re running plastic ones.
Now might be time to go through all the cars and look for something strange like an axle binding in a journal, a truck that has some obstruction to it’s pivoting, etc.
It seems to me that still something is not adding up here.
Greg
R.J. DeBerg said:
Paul Burch said:
Must be track or radius. I have been running a 15 car set for years without problems.
X 2 as I’ve had good success running mine also. Later RJD
x3
" Rooster " said:
R.J. DeBerg said:
Paul Burch said:
Must be track or radius. I have been running a 15 car set for years without problems.
X 2 as I’ve had good success running mine also. Later RJD
x3
What is the minimum track diameter on your railroads? Mine is 9 ft but only for a small part that eases in to it with 10ft. Everywhere else its 10 foot diameter. I never had any trouble running set 2 sets of 5 with a set of 2 at the end. The trouble came when I ran a set of 4 pulling everything you can see in the video. That particular train was pulling a lot weight behind it. It had 1 tanker, which has to be the heaviest car I have, and 4 center flow hopper cars. Those 5 combined are definitely much heavier then an equivalent 5 car container setup. It was also towing 3 box cars, one caboose and 3 small hopper cars.
I suspect that if I had a train consisting of just 15 sets of container cars, no weights would probably be necessary.
To answer John’s question regarding wheels, the wheels on the container cars are metal. All the wheels on all my cars are metal.
I, also, lower the USAT Intermodal Car and use body mount Kadee 907 centerset couplers. Not only does this improve the operational physics but is more prototypically realistic. The cars should always be weighted more if traversing tighter curves.
The illustrations below shows a more favorable attitude of the Kadee knuckle coupler closer to the outer curve rail (compared to truck mount coupler) on 8 foot diameter track curves. This is behooving with respect to coupling the SD70 - with its excessively pronounced pilot end overhang and coupler projecting way beyond the outer curve rail - that with otherwise truck mount coupler imparting twisting forces to it, jamming wheel flanges against the railhead asking for derailments
-Ted
Nicolas Teeuwen said:
What is the minimum track diameter on your railroads? Mine is 9 ft but only for a small part that eases in to it with 10ft.
Same…without the easement but I have a few more 4.5’ into 5’ radii curves than you do I believe. Once again I also run some 35" long scratch built cars as well with no issues.
Nicolas,
My railroad minimum diameter is 10 foot, most with easements, but the indoor part rail yard access is 8 foot diameter. Straight track sections are placed within “S” bends.
-Ted