help decieding on ho diesel engine

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bristolman

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its really confusing . you read that if you buy this ho engine with great pulling power , the smallest radius it will run on is 18 . ive bought a passenger engine now i want to buy a diesel . when you do searches on the engines people are using ( great running / pulling power ) they arent made anymore or not cost effective . looking for advice for a beginner looking for that engine that will pull yet be cost effective ( still available )( only want new ) . confused so help if you can .
mike
 
First of all, you state that the diesel engines you've seen advertised "will only run on 18" radius". Just how tight a radius do you want to run? About the tightest curvature track that is readily available is 15", so you will have to choose a short wheel based engine. This will probably limit you to one of the SW-series EMD switch engines (which were used on branchlines for road duty until the GP's came along), or the GP-7 or later. Also, if you go with the earlier "covered wagon" units like the FT's, F3's, or F7's, there are a number of units available from several manufacturers. You may need to decide what era and what road names you want, as there are limitations on these, depending on the manufacturer. You also need to decide if you want DCC and/or DCC with sound, or whether plain DC and no sound will do. This factor will affect the cost by about $100 per unit for DCC over straight DC.
One thing you can do about getting more pulling power from diesels is to do what the prototype railroads do...MU (multiple unit) them. I've run the old DC powered Athearn F7A and F7B or a pair of A's (back to back) for years (they are about 30 years old now, maybe older...still run fine). They match fairly well as to speed without special modifications, and will pull about anything you want up a 3-4 percent grade. If F7's will work for you, you might try to pick up some of the older Athearn units at model train shows or on e-bay. Get the "Super Power" models, the ones with the flywheels on the motor shafts. Same is true of the SW1500's (what Athearn called them, although some debate what prototype model they are actually). Otherwise, I have lately run some of the Walthers/LifeLike Proto2000 F7A&B units with DCC and sound, both powered, and like them well. Just depends on your criteria, and pocketbook.

Highball on #1!
 
ho engine descision

thank you that helped . i will stick to 18 r (smallest when i do my layout ) , that said what would my options be then ?
mike
 


I really can't say about the SD-40-2. Some six-axle diesels will work run okay on 18" radius track and some won't. In some instances, even though the locomotive will negotiate the curve, the overhang and coupler swing may not be sufficient to prevent derailing of cars coupled to it. Six-axle diesels may have some difficulty with #4 turnouts, depending on the brand and the actual angle of the diverging track. Atlas so-called #4's are actuall slightly easier. I've run Athearn SD7's on 18" radius and #4 Atlas turnouts. I've also run Proto2000 E8's and recently tried an Athearn SD60, the former ran fine, but the SD60 was not quite as reliable in a few spots. One technique is to remove the wheels from the center axles, leaving the axles and gears intact.
 
6 axle diesels will get around 18"R curves but they won't be happy about it. There is a noticable drop in speed as friction increases in the curve. This would affect powering power too.

One simple way to improve 6 axle diesels, and long rolling stock generally, on curves is to use easements. For beginners the easiest way is to use set track curves with larger radius sections leading into and out of the curve.

This webpage explains using Kato N scale uni track, but the same principle is applicable to other scales also:

http://modeltrains.about.com/od/layoutconstruction/tp/curve_easements.htm

The easement will help avoid a sudden slow down between straight and curved track, but will add an inch or two to the size of the curve.
 
bristolman said:
its really confusing . you read that if you buy this ho engine with great pulling power , the smallest radius it will run on is 18 . ive bought a passenger engine now i want to buy a diesel . when you do searches on the engines people are using ( great running / pulling power ) they arent made anymore or not cost effective . looking for advice for a beginner looking for that engine that will pull yet be cost effective ( still available )( only want new ) . confused so help if you can .
mike
Click to expand...

are DC or DCC? If you are looking for low cost, maybe the Athearn Blue box engines The did a nice GP38-2 and SD40-2. Their details pale compared to today's engines. However, I have both that are over 20 years old. Both will go around a 18" rad. curve. But the car behind the SD may derail depending on coupler, wheel base. For pulling power the Proto2000 are better than the Kato. Kato's are smooth runners. I'd recommend 4 axle on the 18"rad. curve, though. Good luck. Phil
 
yeah, the newer engines don't seem to pull as much as the older less detailed engines. My GP38-2's will out pull my 40x's upwards to 40% greater. My Atlas and Kato power are the weakest. I have a pair of Walther's P2k,Athearn Genesis and Stewarts F units and they are close with Stewart being the slightly stronger
 


2 engines

not ready for dcc yet , but buying dcc ready when i do purchase . i read (google search ) , the atlas ho are more consistant running at the same speed ? true ? ( those who buy atlas )
mike
 
bristolman said:
does everyone just use 2 engines to pull their longer trains to put less stress on the engines ?
mike
Click to expand...

I think it isn't so much a case of putting less stress on an engine as it is tractive effort. Most (unless grossly overloaded or have traction tires) HO model locomotives will slip their wheels under an "excessive" load, whether that load is from having too many cars or a steep grade. This is also what happens with the prototype. For most of us having too many cars is less of a problem with most of us than pulling trains up steep grades, as our layouts aren't big enough to allow long, long trains. My layout fills a 14 x 14' room around the walls and with a pennisula. My longest trains are usually passengers, with some old aluminum cars mixed with Athearn passenger cars. I can get a single Proto2000 E-unit to pull six cars up a 3 percent grade, but anything longer doesn't fit my passenger terminals. Nonetheless, I run a pair of powered E's because it looks better and does make it easier to pull the ruling grade.

On freight trains, I can run just about any train that is a reasonable length can be handled by a pair of powered F's, a pair of powered Geeps or a single SD7 (Athearn blue box). But I generally run a dummy third F, just because it looks right, and doesn't take much room (about one 40-50 ft. boxcar worth) in the train.

It is easy to get DCC locomotives to run at the same speed. All you do is program the speed CV's until they run at the same rate (you can eyeball this by running them with a little space between them and see if one leads or lags the other. A Proto2000 F7A/B set I have runs fine with each other with no changes to the CV required. They were sold as a set, so may have been matched by the factory.

With DC it can be a little more difficult. Similar models should run at the same speed with the same throttle setting, but differences in motors, gear wear, etc., can make that problematic. I have quite a few older Athearn F's that I just kept swapping chasis until I got pairs that run together.

So far as steam locos are concerned, I've had very few problems with having to double-head even up a 3 percent grade with practicable-length freight or passenger trains. I have pairs of kitbashed 2-10-2's and 2-10-4's which are DC only, and have had their motors replaced with Canon coreless motors, which I've double-headed on modular layouts that pulled dozens of cars in a single train. But this was more for show than necessity.

It takes more traction to start a train or go up a grade than it does while rolling. This was where the diesels have the advantage over most steam locos on the prototype. But with electric train locos, it's closer (except for the diameter of the drivers on steamers vs. the smaller diameter on "diesels."
 
bristolman said:
does everyone just use 2 engines to pull their longer trains to put less stress on the engines ?
mike
Click to expand...

I usually run 2 6 axle units on trains up to 50 cars. The same train gets three 4 axle units. I have had 2 P2k SD60's pull a 60 car train up 2% grade, the same train required 3 GE dash 9's. The 4 axle units are GE's, Alcos or GPs. No end cab switchers. Phil
 
Mike,

Since you are just starting out, you'll want to go with a 4 axle locomotive. 6 axle locomotives are more picky about trackwork and derail more often. Any newer model by Kato, Atlas, Athearn and Walthers will work well. I'd be wary of Bachmann even though they are much better than they used to be. Bachmann spectrum steam locomotives are good, but steam in general pulls less and derails more often than diesels. I'm also favorable to the Life Like Proto 2000 (P2K) locomotives with are well detailed at low cost. Some early P2K diesels have a split gear issue that's easily fixed.

Now here is a good set of power for passenger trains and the like.
http://www.ebay.com/itm/Athearn-8024-RTR-HO-F7A-F7B-AB-Set-Southern-Pacific-SP-Daylight-7034-and-7134-/270911490138?pt=Model_RR_Trains&hash=item3f1395485a

And for freight trains, this kind of locomotive would be ideal;
http://www.ebay.com/itm/HO-RTR-GP38-2-SF-Freight-2370-Athearn-78939-/370577247437?pt=Model_RR_Trains&hash=item5648200ccd
 
I have had a pair of Atlas GP38's move 60 cars uphill with no issues at all. Coming out of the yard, there is a grade heading west. I would not send a road train out powered like that, this was a switching move.

I rarely run one unit. Even my switching moves/locals are usually a pair of units, various styles of Geeps or SD38's or 4 axle GE's. Most of my road jobs operate with at least three units, a mix of 4 and 6 axles.
 


Small, light locomotives usually don't have much room for extra weights, so either traction tires or Bullfrog Snot on the treads will help. Obviously, there is a point of diminising return, and you don't want to overload the motor. Best is to check the load with an ammeter under full slip. You need to know the rating of the motor, of course. It's easier with a DC setup, unless you can locate an AC ammeter. Personally, I generally quit when it's obvious the engine is laboring. The prototype usually figured out how much each class of engine could handle, under what grade and load, and either tacked on a helper or double-headed, or added an extra diesel unit.
 
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