About three or four of my cars seem, to me, to be "underweight" since they tend to jump the track at turnouts. No such problem with most of my fleet. Any thoughts on how to add weight (or weights) to such cars? Or am I all wet and the problem/cause is omething else???
Car weights and derailments Have you checked the weight using a postal scale? There is an NMRA formula for N cars, that I seem to recall is 1/2 ounce plus .1 ounce for each 1o scale feet of length, or 1 ounce for a 50 ft. car. While this is a likely problem, it may be that the trucks are not swiveling properly or the wheel flanges are catching on something, so check these two first. There are various weights available. I am lazy and use 1/4 oz. stick on weights, although I also have some lead putty to use on cars that do not come apart to permit installation of weights inside. On these, you can pack the putty between the underframe beams. :cat:
Under weight cars It also sounds like your flanges no your wheels could be to wide or too narrow and "picking the points or or guardrails fo your switches. so check the guage ov your wheels. HAPPY MODELING! :shade: 282 mike
I use 7 gram weights to underweight cars. You can get some weights at Fishing and Tackle Shop. Stay cool and run steam....
How can wheels be out of gauge when they are one piece plastic????? I can see if they are metal and two or three piece. More information is needed. By the way I did some math on scaling down weight. A car, forty feet long and weighing 20 tons empty would weigh .15625 ounces in N scale. The same car loaded with 100 tons of coal would scale out at .9375 ounces or roughly the NMRA standard.
The formula I know of says 1/2 ounce plus .15 ounce per inch of car length. Thus, a 50' car should weigh .5 + (.15 x 4 inches) = .5 + .6 = 1.1 ounces. Not much of a difference.
Inkaneer, not all cars come with one piece plastic wheelsets. Assuming stan is having trouble with some of these, checkin the guage is a cheep place to start. :thumbs_up: 282mike
My personal car weight formulas Here are two formulas I use to determine optimum car weight for my n-scale cars: To convert any prototype car length to n-scale car length in inches: Prototype car length in feet x 12 / 160 = n-scale car length in inches To determine a desired car weight for n-scale: Actual n-scale car length in inches x 0.12 + 0.25 = Total car weight in oz. To determine how much added weight is needed: Subtract actual n-scale car weight (a postal scale is excellent for this) from Total car weight. For example: using these formulas a 40 ft. prototype car is 3.0 inches in n-scale and the n-scale car weight comes out to 0.61 oz. I use these formulas with many of my "problem" lightweight cars that have/had “problems”… all "problems" were corrected. Here's a InterMountain Kit 40 ft. steel reefer that weighed 0.45 oz (using a postal scale). As the formula shows, this car should weigh at least 0.61 oz. For this particular car, I simply 'rounded' the total weight to 0.65 and added a 0.20 weight to the car. I cut the weight in half and cemented each half directly above each truck. The car also has MT-1000 trucks and operates trouble free. Not all n-scale cars will allow for this mounting method... so experiment first where and how to put the added weight in any given car type. CAUTION: This weight formula solution works for me… you may may/may not have similar results. Hope this helps... :teeth:
I try to make all my cars weigh between 0.8 and 1.0 ounces, regardless of length. That seems to work best on my layout.
Stan, Try running the 3 or 4 derailing cars at the end of the train. If they still derail, chances are improper wheel gauge or something other than weight is the culprit. If they don't derail then you can probably blame weight. Ben
I use the recommende NMRA/NTRAK weight formula as has been mentioned in this post. For my scale, I've drawn a "ruler" with the weight required for a given length written directly on the scale's table. I place a car on the scale, read the weight, check the ruler to see what it should weigh, and make the adjustment. I then add lead weight up to the required weight. Double sided foam tape or Walther's GOO works well to attach the weight. I also body mount couplers and use low profile wheels. These three things have almost eleminated derailments, even on NTRAK layouts. You should know that there are many opinions on this topic, but that's what works for me.
While I do NOT disapprove, or discourage the use of NMRA/NTRAK weight standards, for me, they are too "generalized" than I find acceptable for car weight use with my own equipment. :unsure8ao:
An alternative to wheel weights or sheet lead, etc. is lead bird shot used in shotgun shells. This is really good for covered cars like hoppers and boxcars. Just attach with white/yellow glue. Available from your local gunsmith at reasonable price and usually in some quantity you wouldn't use in umpteen lifetimes! (Don't ask me how I know! )
Thanks to all for the many sugestions & help. Will let you all know what works best for me after I try your advice.
UNDERWEIGHT FREIGHT CARS Thanks to all your suggestions, I worked out a system for correcting car weights that is working well for me: First of all, I checked the wheel width gauges (with the NRMA gauge) and all passed. (All but two of my fleet have plastic wheelsets.) Then, using a postal weight scale, I checked the car weights. Sad to say, all but one weighed a half ounce or less! My cars are a mix of Atlas and Bachmann, with one Micro Trains 40' foot reefer. THAT was the only one which weighed in over 1/2 an ounce! (It weighs 0.75 oz.) And all 6 of my Con-Cor 80 ft heavyweight passenger cars -- which by formula should weigh about 1.5 oz -- checked out at barely 1 oz. What i am using, to add weight, is some LEAD SHEET which I found in the plumbing department of my favorite (independent) hardware store. For less than a buck, I got a piece of sheet approx. 1 ft X 6 in weighing about a pound. Since it is only about 1/16 in thick, it is very easy to cut with a small tin shears -- or even a good pair of scissors. The beauty of using pieces of lead sheet is that it is very malleable and easily formed or folded to fit the mounting space available. Most of my cars have small flat pieces mounted on the underframe -- using Loctite Super Glue (which bonds to plastic & metal). Except to a "purist" there is hardly any way to see the modification to the cars. And "yes", my cars do run better on my layout!
For adding weight, I just use fishing sinkers (although shotgun pellets would work just as well) embedded in Funtak. Easy to adjust the amount, forms into nooks and crannies, but does look pretty goofy on the underframe. For those, I use tungsten putty, which is similar to lead putty, but basically non-toxic.
