Are there NMRA RP's for tender weight? I have several Spectrum tenders that seem to be quite light and am wondering what the correct amount of weight should be? Any thoughts?
No -- there are no NMRA standards or RPs for anything dealing with locomotives or tenders. The NMRA Standards and RPs are concerned primarily with track and electrical wiring/DCC.
The NMRA web site has an index of Standards and RPs.
http://www.nmra.org/standards/sandrp/consist.html
Trying to set weight standards for tenders would be impossible considering the different types of tenders -- plastic or metal -- solid or hollow -- square or Vanderbilt -- short or long --
The NMRA may not have a standard or RP for this, but adding weight to tenders is a fairly common practice. In the days of DC brass, you needed the extra weight to help with maintaining contact. Even brass tenders are fairly light, mostly plastic ones even lighter.
I only have narrowgauge steam locos and used 1 oz in the tender. You don't want to go too heavy as that limits pulling power, but a couple of ounces sound right as a possible maximum. Worth trying.
BTW, you didn't indicate any problems, like tracking difficulties, derailing, etc, but if you are, be sure and check things like wheels and trucks, as well as the drawbar, before worrying about adding weight. Weight can help with some problem, but it doesn't really "fix" anything that's not right to begin with.
Mike Lehman
Urbana, IL
I add weight to all tenders, and also modify the coal bunkers to accept loose "coal" loads. The added weight helps improve electrical contact and, when pulling heavy trains, improves tracking of the tender. I run DC, so don't have to worry about accommodating decoders or speaker enclosures.
Most of my tenders, like the one behind this modified Athearn USRA Mikado, weigh about 6.5oz with a fairly full load of "coal" (coke breeze):
This loco has a shortened version of a tender very similar to that behind the Athearn Mikado, and it also weighs about 6.5oz.:
The shorty tender behind this modified brass import tips the scales at just over 8.5oz.:
In my opinion, it's well-worth the effort to add weight to any tender, as any negligible effect on pulling ability is more than offset by the increased reliability.
Wayne
I consider the NMRA car weight RP as a reasonable starting point. Then add more for each additional set of wheels (there are tenders with 6 wheel trucks, pedestal 4-10 tenders and those Santa Fe and Pennsy 16-wheel monsters...) The trick is to get enough weight to assure good tracking without adding more than necessary. The loco still has to pull that thing!
Since my models are nowhere near typical for US prototype practice (6 wheel pedestal tenders?) I won't say any more.
Chuck (Modeling Central Japan in September, 1964 - with tenders that are as light as possible and as heavy as necessary)
If you were to treat the tender as a peice of rolling stock NMRA would say 1/2 once for every inch in length (1 oz minimum)
But I wouldn't worry about it unless you were having tracking issues.
-Don
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
Like Wayne, I weight all my tenders about twice what they would be as cars.
I have lots of Spectrum steam, yes all their tenders are light.
Here is a link to some tips I posted awhile back that you may find useful.
http://cs.trains.com/mrr/f/88/p/181314/1984908.aspx#1984908
Sheldon
I have a Spectrum 4-6-0 with sound and DCC and the tender is constantly coming off the track. I placed some flat steel weights on top of the tender and that seems to help a lot. Now I have to remove the tender shell and see if any weight can fit inside. Just haven't gotten up the nerve to tackle this task as the tender is very small.
-Bob
Life is what happens while you are making other plans!
Like others, I have had to add weight for a couple of reasons:
I had to add weight to both of my Spectrum 2-8-0's and both of my BLI USRA Heavy 2-8-2 steamers. I have them weighted to just a little more than the NMRA RP for rolling stock - Big Difference!
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
Joe Staten Island West
Picked up some sheet lead at the LHS this week and hope to find time to open the tender and see what I can add to the weight. Don't expect to find much room in there! This is a Spectrum 4-6-0 and is quite small (DCC and sound).
OK so Added about 2 oz of weight to one of the tenders and yes I think it does help.
joe323 OK so Added about 2 oz of weight to one of the tenders and yes I think it does help.
Joe,Adding more weight then that might cut down on the locomotive's pulling.
My advice is add just enough weight to keep the tender on the rail-if you are having problems.
I've always thought modelers over weight everything just because of RP20.1(slightly outdated for modern cars) and there's no real reason to add weight in most cases.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
BRAKIE joe323 OK so Added about 2 oz of weight to one of the tenders and yes I think it does help. Joe,Adding more weight then that might cut down on the locomotive's pulling. My advice is add just enough weight to keep the tender on the rail-if you are having problems. I've always thought modelers over weight everything just because of RP20.1(slightly outdated for modern cars) and there's no real reason to add weight in most cases.
Larry,
A four or five oz tender is only the wieght of one extra car, so it will only affect pulling power by that amount - one car. If your loco pulls 20 cars comfortably, then it likely will still pull that many if you add 2-3 oz to the tender.
The fact is that the dynamics of tender drawbars are different than couplers for a number of reasons.
One, tenders are usually much shorter than the loco, creating the same effect as coupling a 75' car to a 35' car.
Two, all the weight of the train is transfered there, and when backing around curves or through turnouts it can create a lot of side pressure.
NOW, if you trains are only 12 cars long, tender weight is not likely to be an issue unless the electrical pickup, binding wires or similar problems exist with a particular loco.
BUT, if you regularly run trains of 25, 35, 50 cars or more, maybe with double or tripple headed steam, weighting those tenders to a total weight of 5-7 oz will provide much more reliable operation - especially in reverse.