MTH ALP-46 required minimum O-72 curves?

A good question on the track radius.  I would tend to believe that 0-72 would be for scale wheels (and likely fixed pilot) version.  If that version has a fixed pilot, then I can see o-72 due to the long wheel base. 

There's a video of a hi-rail version below.  At the 4:50 mark you can see the unit up close, and it is navigating turns much sharper than 0-72. (And the pilot clearly is not fixed.)

https://www.youtube.com/watch?v=_gr6XwWNXNE

If I understand correctly, all 3-rail curves in O-gauge are referenced by diameter of a full circle of those curves, e.g., O36 curves form a 36" diameter circle which has a radius of 18"

Hi Kevin - my suggestion is to contact MTH directly. 

Kevin, O Scale, O Gauge, can run form 1/43 through 1/48.  But true 1/4 gauge modeling is exactly 1:48...  .25 or 1/4 inch equals 1 foot....  You will find many O scale items are 1:45 scale...   Remember the higher the number, the smaller the scale'.... and sized item...

Just an FYI before digging to far and contacting MTH, the 2RS locomotive would be 36” RADIUS as in a 72” diameter circle. The 3RS locomotive is O72 or a 72” DIAMETER circle... hope this helped

MTH Premier NJ Transit ALP-46 Electric Engine 20-5661-1 is listed on line as 1:43.5 scale and operating on O-72 curves. Length is 16-3/16 inches. Just for comparison, the MTH Premier New Haven EP-5 electric locomotive (20-5531-1) is listed as 1:48 scale and operating on O-42 curves. Its length is 17-7/8 inches. The ALP-46 has two two-axle trucks and the EP-5 has two three-axle trucks with longer truck wheelbase. Of course, they both run on 3-rail O-gauge track with rail spacing of 1-1/4 inches.

Based on the length and number of axles, it would seem that the ALP-46 should run on smaller radius curves than the EP-5. However, looking at the MTH on-line images of these locomotives, the ALP-46 sits lower on the trucks (no visible gap between body and trucks) than the EP-5 (clearly visible gap between body and trucks). Therefore, it may be that the ALP-46 trucks cannot pivot through as much of an angle as the EP-5 trucks due to potential interference with the body. Thus the ALP-46 is listed for O-72. This is just my conjecture. You need to check with MTH or a dealer.

MTH European electric locomotives are made to larger scales (1:43 and 1:45) than American O scale models (1:48). The MTH ALP-46 at 1:43.5 is approximately 10% larger than if it had been made in American (1:48) O scale. I don't think this is the reason for the listed O-72 curve requirement but it may be a contributing factor.

I own several MTH Premier electric locomotives with PS1. (New Haven EP-5s and New York Central P2s). They have been excellent runners for twenty years.

MELGAR

if Lionel says 072 they mean it!!

No so with MTH. I have found that smaller radii can work. YOU SHOULD CALL MTH  or test drive one

I contacted MTH today and they provided the following response:

"The ALP-46 does indeed require O-72 curves for its operation, due in large part to the skirting that hangs down from the body.  While the locomotive's length shouldn't be an issue for a tighter curve, the skirting prevents the trucks from rotating far enough to the left or right to negotiate a curve smaller than O-72."

They didnt take a long time to respond to my question.  I figured it would take 3-4 days.

Okay, so that narrows down my locomotive choices. Maybe I'll get a LionChief GP40 and have one of the skilled painters here on OGR do it for me.

Depending on the era of NJT you are modeling, these are always choices as well: 

Obviously 3 of the four are my creations and one project isn't nearly done yet.  What I call the C34-7H is in back pieces as I need to rebalance the trucks so the weight was is the two powered wheels.  The E60 is two Williams shells combined with no power, but I have a BDO shell that sits on a SD60 chassis that will look much better with the correct side frames when I get to that project.

The ALP44 is stock Atlas.  MTH released the F40PH in NJT too recently. 

On a separate note the scale of the European style MTH is true O scale.

In US terms it would be 17/64" scale which puts the rails at 4'-8 1/2" apart as opposed to 1/4" scale which has the rails at 5' apart.  Talk to a Proto-48 modeler about modeling O at 1/4"   That's a hardy group of modelers. 

Don't want to stray too far off the subject here though.  Someday an ALP46 would be nice for my NJT collection. 

FWIW. MTH's ALP46 used to be rated o54 on its original release some years ago. Also, though I wouldn't recommend for a permanent layout, the ALP46 can negotiate and run on o54 tubular smoothly and even o48 Fastrack. The trucks rotate just fine. I tried this "just to see" and I was pleasantly surprised. The absolute minimum diameter curve it'll run on is o60 FT on my next running layout to be safe.

GG1 4877 posted:

Depending on the era of NJT you are modeling, these are always choices as well: 

Obviously 3 of the four are my creations and one project isn't nearly done yet.  What I call the C34-7H is in back pieces as I need to rebalance the trucks so the weight was is the two powered wheels.  The E60 is two Williams shells combined with no power, but I have a BDO shell that sits on a SD60 chassis that will look much better with the correct side frames when I get to that project.

The ALP44 is stock Atlas.  MTH released the F40PH in NJT too recently. 

These are awesome! Fellow NJT fan as well. 

Jonathan, I'm not running any particular era of New Jersey Transit or NJT in general.  I liked they way they look in real life, like in this photo at railpictures.net #77677 , I want to have a collection of New York City area transit + commuter trains, and  just wanted to have a nice consist to watch run.  I have 5 Comet Coaches to go along with an ALP-44 that I purchased (that's another thread and soon to be the topic of another thread I'm going to start tonight).  Two of those Comets are Cab Cars and I will be looking to trade one for a Coach Car.

Do you happen to have the Owner’s Manual for the ALP-44?  Is it possible that you could scan a copy and e-mail it to me?  Also, does the ALP-44 require the LocoMatic box to run properly with all of its features?

Thanks.

Kevin, if you can get an MTH ALP-46 at a good price, then try it on your curves and if ... if ... you get a problem use MTH's useful comments and cut/file away as much of the skirt as you need to.  As a 2-railer I'll probably get shouted at for saying so, but enjoying 3-rail is about getting O-gauge empires in tight spaces.  Hardly anyone seems to look at those details nearer the track and maybe you'll be the only 3-railer showing the fix!

Jason

Kevin,

I have the manual for the ALP44. Unfortunately it is in storage at the moment.  I do need to get over there soon though.  I'll remember to dig it out.

All the features can be used without the Dallee control system but the manual is very helpful in setting it up.

Kevin:

Please see my answer here, including the manual.

Perfect!