Gauge for pulling power?

Micro Mark has a Digital Pull Meter I have one of these. Or you could possibly use a fish weighing scale from Bass Pro or Cabella's? I think others here have also mentioned using the Micro Mark scale.

I have one of those.  It's pretty nifty.  

You can rig up a scale for weighing fish to do the job pretty easy.

I have a $3 digital scale, it does a pretty good job just coupled to the rear of the locomotive.  It's only lack is no maximum value lock.

 

What do you guys do with the information obtained from these "pull meters?"

Uhhhh.  Not a whole lot, but its interesting and fun.  In an real sense, my locos fall into to categories, those that pull, and those that don't.  I think like most owners, I know which is which.  The difference between 30 and even 40 ounces of pull is rather lost on any practical application I have. 

I have a great train notebook that I keep all the statistics in.

 

Seriously, it's 99% for discussion, as Lee says.  Truthfully, I bought the little scale on a lark, if it had cost much more than $3, I wouldn't have it.

 

I think if you are a "pull-thingee type guy" you just get one and play with it.  It is interesting sometimes:  One time I had a loco without traction tires -- I think it had had them but not  by the time I bought it.  I measured it before and after applying "bullfrogsnot" to the wheels to improve traction.  It worked, traction increased from something like 16 to 30 ounces or something - about doubled.  I then scrapped off all the bullfrogsnot and applied a coat of the plastic sold as pliers -handle coating (you find it for that in Lowe's and Home Depot - much much cheaper).  It worked just as well.  I'm not sure that knowledge is valuable, but it was a fun little project. 

I got a scale about a month ago and built a "test track" as a result of a thread on the subject. It's been a lot of fun and......quantitative. I've been adding a second motor to my postwar Alco sets and just today completed tethering together two postwar (motorized) Budd cars. It's interesting comparing my results on those to the pulling power of my F3s (and other engines touted for their pulling power). I've also been experimenting with putting lead ingots in some of my engines and it's great to measure exactly how much difference it makes.  I've yet to measure my MTH and Lionel modern stuff, mainly because I know they've got an advantage with the traction tires and double can motors. 

 

-Roger

 I do remember a fishing scale being used by my Grandfather. I think I still have it; a large black Zebco I think. But I always just compared engines by a grouping of heavy weights & post war first, then adding a few mpc cars & flats till I got wheel spin.

  A whistle tender, two die cast filled Evans Auto Loaders, two milk cars, cast flat, cast work caboose, scale NYC stock car, geared gunfighter car, two "weighted as empty" tankers, various box cars, and then a flat or two.

 One interesting thing I noticed once I had grade. On two near identical traction tire Pulmor NW switchers, one out pulls the other one car on flats, but not up a grade, it loses by a car there! (bolster looseness?) 

 

Okay...I understand...just making sure I was not missing something...it's a gadget and most of us just like gadgets.

 

 

BINGO!

 Numbers can be fun.

  A tool to change the way fun is had, for finding the best mods, max pull, or simply to find out if your brothers train out pulls yours. Yep gadget.

Back to back "tractor pull" style, isn't unheard of either

While waiting on the Micro Mark one, found a suitcase digital one that goes to 100 pounds for less than $10, just kind big. Its capacity might work for your "Tractor Pulls" Adriatic, sadly we normally just bump into parked objects:-)

 

It reads about .5 pounds max when pulling a freight train from standing start, then dropping to .3 pounds rolling along. All tests were done on level track, never got any higher even through curves. 

Do these numbers seem accurate to any of you that have measured resistance?

to me when I start stripping traction tires that's an indication there are too many cars in tow. and its time to lighten the load

Something doesn't sound right here.  My test track has the scale in a fixed position, with the engine pulling away from it. How are you measuring a moving train?  And those numbers seem really low.

 

Roger

NOT TRUE!!

 

Our own Mr. Jim Barrett did an article sometime in the past. My memory fails me, I cannot recall which run. It can be used in diagnostic work on power units over a period of time. He explained how and why.

Much earlier, he performed some for fun tests in his, BackShop series.

We were just measuring the force required to pull the train itself, we wanted to see if we would be overloading just one powered unit. One train was about 15 MTH hopper cars and a dummy unit, the others a mix of Atlas, Lionel, MTH, and Weaver scale length freight cars which was a bit longer but may have had less trucks due to the length of some cars. We did not pin the gauge down and have any engines pull against it like the magazine tests do.

 

Going to try it again with other cars being brought over Sunday. Just surprised that the gauge read less than a half pound required force. Unlike the Micro Mark, this one has a hand grip type handle so We could not place it between the engine and cars.

Fun tests is what gadgets are for.  I didn't say it couldn't be useful, but it's hardly an indispensable tool for model trains.

 

If it's fun you're after, take your drawbar pounds measurement on your rolling consist and multiply it by the speed.  This will give you scale Horsepower albeit you need to fuss with scale factors.  Compare your HP output with that of the prototype engine.  You might be amused.  Then compare your power output with how much electrical power (Watts) you're putting into the engine.  Haven't seen it in OGR but you get amusing discussions amongst the rivet counters in HO forums.

 

Haven't seen a functional (recording) Dynamometer Car in O-gauge but it's a recurring topic in HO.  From Wikipedia:

 

A dynamometer car is a railroad maintenance of way car used for measuring various aspects of a locomotive's performance. Measurements include tractive effort (pulling force), power, top speed, etc.

I've seen up to about three pounds in extreme cases.  I've heard of tests up to five.

 

Someone asked about measuring it static (not moving) versus moving.  You ahve to measure it moving.  You don't get a true reading of the loco's pulling power when its NOT moving, and running it any time with a locked motor rotor is not a good idea.  

I was reading the print copy of OGR last night and George Brown reported 7 lbs 2 oz pulling power in his review of the new VL Big Boy. He said he went back 10 years in his records of testing and couldn't find anything to out do the new VL BB. Might be a new entry for the Guiness Book? (However you spell that, I mean the record book)

We made sure all the axles received a drop of oil and were very surprised at the small amount of force required to get them rolling, especially with a big dummy engine. Even with a 100% tester error it would still be less than a pound required to start. Mainly just concerned about using one locomotive to pull 15' to 20' trains without having to worry about overload heat. Now it is just running out of smoke fluid. Awaiting the smaller tester to make a rolling car for it. 

I suspect that pulling any reasonably modern freight cars, 15-20 cars are not much of a challenge for almost any decent sized locomotive.

Modern cars, yes. It is astounding how little resistance some of the best have.  But I have some old postwar cars I have done everything I can too, including using graphite lube which seems to work best, but even so they just have high rolling friction: maybe the bearings wear out?  Something like the WBB 44 tonner can only pull about seven of eight of them before it starts to struggle. 

Let's be fair Lee, the 44-ton locomotive isn't really designed for that either.  I did say "decent sized locomotive" after all.

 

I agree, the PW cars have a LOT more rolling resistance than modern cars.

 

 

A true reading of what? That is the question.

Some are measuring what it takes to pull a train if everything is moving.

 A loco hooked to an immovable scale, dead stop to wheel spin, and its variations from throttling speeds give a base of the locos usable capabilities. Starting is most often the weak point, and its traction at the heart. I've not stalled a loco by pull weight, or had it reach a visible steady speed only to stop accelerating from wheel slip. Wheel spin at start is always the limiting factor so I sought to know those points in my locos.

 Most of my hi-tech experiments were done before my age hit two digits