Well, it’s finally here, the American Flyer SD70ACe. This is the 6-42505 BNSF scale wheel version.
What follows are my observations and opinions.
Overview:
Wow. Out of the box, this locomotive is impressive. It’s a full 2” longer and a little taller than the U33C. I’ll admit to not being 100% familiar with the prototype SD70ACe, so I can’t tell you if any rivets are out of place, but BNSF units have the headlights in the nose, not between the number boards.
Prototype image: RailPictures.net c. Warren Calloway
Overall, details appear to be based on Union Pacific SD70ACe’s.
Prototype image: RailPictures.net c. John Witthaus
Regardless, the SD70ACe sets a new standard for American Flyer diesel locomotives.
The first thing I noticed was the pilots don’t flop around with the trucks, more about that later. The next thing was while the handrail stanchions are still Delrin or similar material, the railings and grab irons are wire. Very stiff wire. These railings are a lot more durable than the U33C’s, but things can apparently still get bent slightly either during packing or shipping. I’m working to straighten out the front railing a little better on this BNSF model, I’m not quite there yet.
There’s a largish gap between the truck side frames and wheels to allow room for the wider tread HiRail wheel sets (and maybe also the result of rescaling data from the O gauge model file.) For the folks who this might bother, the side frames are held on by screws. I haven’t removed the side frames, but it looks like it may be possible to elongate the mounting holes on the side frames and move them inward a bit.
Paint is even, lettering is crisp and there’s no overspray or smudges I can see. There’s two crew figures in the cab and a gray plastic shield to hide the front motor from view.
The model has see-through radiator grills…
…and fan blades visible in the cooling and dynamic brake fans. Blow on them, they will spin.
The radiator fan assembly lifts off, revealing the rear motor, smoke on/off switch, TMCC program/run switch and volume control pot.
Even though my SD70 came factory equipped with scale wheels, Flyer coil couplers were factory installed. Mounting brackets and screws for Kadee 802 couplers are included in the box. Kadee couplers not included.
China Drive Syndrome:
The drive system has been on just about everyone’s mind. There’s been a lot of fear and loathing particularly from the scale side when it was announced the SD70 would have twin vertical DC motors. We scalers have been collecting pitchforks and torches in anticipation.
Well, I’ve blown out my torch and put the pitchfork away… It’s not evil.
The SD70’s drive runs smoothly and has good slow speed response. It runs as well as any traditional horizontal drive locomotive from AM or (former) SHS in my opinion.
The SD70 also tracks through my Shinohora #6 and Old Pullman #5 turnouts with no trouble.
Command/Conventional Control:
The SD70ACe is also the first Lionel/American Flyer model that will run on AC conventional, TMCC/Legacy, DC analog and DCC. No switches to set, nothing to remove, replace or rewire. The internal electronics senses what is applied to the rails and responds accordingly.
I’m going to discuss DC and DCC operation here. I’ll leave it to conventional AC and TMCC/Legacy users to report their findings as I‘m not really equipped to test these modes properly, other than verifying the locomotive does also work on AC and TMCC.
Analog DC:
Note: The SD70 will run on DC, but it has to be pure DC. In discussions and experimentations with the Y3 here on OGR, it’s been discovered that some contemporary DC power packs don’t output a pure DC signal and the model’s radio board reacts to the anomalies. As a result with pulsed DC, the SD70 will run fine in reverse, but sit with the horn blowing in forward. Several different power packs have been tried with the same result. Reversing the wires to the track has no effect.
Lionel is aware of this issue and is looking into it.
My DC throttle is an old GML Enterprises 3 Amp throttle using the fixed AC output of an old MRC power pack as a power source. I’ve had no problems running the SD70 with this particular combination.
With conventional analog DC operation, the prime mover sound activates at about 5.9v, lights come on around 7.9v and the locomotive begins to move around 8.5v. Speed control is a good as your throttle. The locomotive stops moving around 8.5v and shuts down around 6.2v. In DC, there is no independent control for the horn or bell. Direction is controlled as usual with the direction switch.
I don’t know if add-on products like MRC’s “Black Box” function controller will access Lionel’s DCC sound features in DC mode.
DCC:
My DCC system is an MRC Prodigy 2. I’ve tested the SD70 using the tethered throttle and the wireless upgrade throttle.
Lionel describes the SD70 as “DCC enabled.” DCC gearheads expecting a decoder with a million CV’s to play around with are going to be disappointed. The factory installed DCC decoder is built into the TMCC receiver and is designed to control Lionel’s TMCC/Legacy electronics, which control the locomotive.
However, the DCC decoder has the NMRA standard CV’s for long and short addressing, consisting, acceleration and deceleration delays. Available user CV’s are listed in the manual, along with Function Key assignments. The decoder is capable for 14, 28 and 128 speed steps.
The manual is viewable here, DCC functions begin page 24:
http://www.lionel.com/media/se...541748171SD70ACe.pdf
CV50 is an interesting one. Depending on it’s setting: 1 for lead; 2 for middle; 3 for rear; it will control the lights within a consist so that only the front lights of the lead unit and rear lights of the last unit will respond to direction changes. Any intermediate unit will be lights out. The horn, bell and TowerCom in the lead unit will be to only ones respond to commands when in a consist when CV50 is set.
I have had no problem programming the decoder on main or the programming track, but needed a booster such as one made by DCC Specialties to do a reliable read-back function on the programming track.
As expected, overall control of the locomotive is finer with DCC than with straight DC.
Pilots:
“Swinging pilot? What swinging pilot?”
“Oh, THAT swinging pilot!”
OK, The pilots swing on the SD70. This has been a REAL sore spot on the scale side, so I’m going to spend some time here.
The pilots are mounted to the locomotive’s frame on a bracket that allows them to swing independent of the trucks. They will remain aligned with the locomotive body through curves unless there is a car or locomotive coupled to it. There is still a gap between the pilot and carbody, but it is less than the U33C’s.
Now, for those who would still be upset with this arrangement, Lionel has provided spacers and screws to mount the pilots to the sheet metal frame. Simply unscrew the Flyer coil coupler and bracket, unplug the coupler cable and remove the pilots.
Four spacers and screws are included to “fix” the pilot. The spacers go between the pilot and the sheet metal frame. The instructions for mounting the pilots and Kadees escaped being put in the manual shipped with the locomotive.
The pilots must be mounted to the frame before the Kadee coupler brackets are installed. Correct screws are also provided for this. It’s also wise to mount the Kadee’s to their brackets before installation, they’re a lot easier to handle that way. Once installed, the Kadee couplers are at the correct height according to the Kadee coupler height gauge.
As before, there is still a gap, about .033”, as opposed to the U33C’s .055” on straight, level track. A clever modeler could fabricate and paint a filler piece to fill the gap if he so desires.
I found the pilot gap on the rear of my BNSF unit to be greater than the front pilot. However, the rear pilot and coupler were both sitting at the correct height and the body appeared level. But, after a little investigating, it appeared the rear of the body wasn’t sitting quite all the way down on the frame. By pressing carefully on the hood and frame, I could see a little “bounce” and close the gap. It was very subtle, I probably wouldn’t have noticed it for a while if I wasn’t taking gap measurements.
I tried tightening the two screws underneath the end of the long hood that hold the body down, but they wouldn’t budge. Not wanting to strip the mounting lugs, I removed the screws and added some thin washers as needed to pick up the slack. Now both front and rear pilots have the same .033” gap from the body. A minor issue and I don’t know if or how many other units are so afflicted.
Sounds:
I’m not real familiar with exactly how an SD70ACe sounds. When I see them on the BNSF Chicago-Aurora racetrack, I’m usually more concerned with getting somewhere rather than railfaning and groovin’ to the sounds, plus they’re usually mixed in with GE’s. I’ll take it on faith that this is how an individual one sounds up close and personal. There are some EMD signature sounds I recognize in the prime mover mix, the horn and bell sound good. The prime mover sounds will “notch up and down” as the locomotive accelerates and decelerates in both DC and DCC. In DCC mode, the horn will sound as for as long as F2 is pressed.
However, the braking sound is well… sorta sounds like an elephant in heat. It sounds every time the locomotive is brought to a dead stop, so don’t stop it near a zoo or circus. Or… DCC users can set CV54 to 0 to turn brake squeal off. And, of course, there’s TowerCom.
Lights:
Numberboards are illuminated as long as there is DCC power applied to the locomotive. The cab lights and headlights in the direction of travel will light when the locomotive is selected. The cab lights go out when the locomotive starts moving. The ditch lights will illuminate in forward only once the locomotive is moving and will alternate when the horn is sounded per current prototype practice.
Smoke:
Yes, The SD70 smokes where and when it should with a fan driven smoke unit. I’m not a smoke enthusiast, so I’ll leave that for someone who is to talk about. With DCC, smoke on/off is controlled by F8, or the smoke unit can be turned off permanently by the switch under the radiator assembly.
Curves and “Fixed” Pilots:
Now, this is a big locomotive, and being able to run on sharp curves is more about how far the coupler is from the truck pivot axis than overall locomotive length. Mounting the pilots to the frame brings its own perils of overhang. The following shows how much overhang there is on a 33” radius curve.
And on a 29” radius curve:
29” radius seems to be about as tight as you can go with fixed pilots and Kadees with this locomotive:
As the above picture shows, when coupled to a 50’ boxcar, the Kadee couplers are just about, if not at the end of their range. A more modern car with an extended draft gear would actually make the situation a little better, but I don’t have any to test with. If you have sharper curves, you may want to consider leaving the pilot pivoting bracket assembly in place and let the pilot swing.
My 29” radius curves are inside passing tracks, and I haven‘t run into any issues with derailments so far because of the fixed pilots. Otherwise, my mainline curves are 33” radius and there have been no troubles there.
Conclusion:
Well, I’m finally going to shut up!
But… not before an apples to oranges editorial.
Submitted for your approval, a comparison of the Flyer SD70ACe with a custom painted and detailed River Raisin brass SD9, the only tricked-out S scale diesel I have that’s close enough to compare:
There will still be some in the S Scale modeling world who will equate anything with the American Flyer brand as toy trains. Maybe they’ll change their minds with the SD70ACe, maybe not.
However, with the SD70ACe I think we can safely say that American Flyer has evolved well beyond the “toy train” stage.
Even with the design considerations taken for the traditional American Flyer operator, the American Flyer by Lionel SD70ACe is a great S Scale model. I’m looking forward to other similar products in the future.
UPDATE 03/08/13:
Additional reviews and information may be found at:
Micheal Greens S Scale blog:
The S Scale SIG (Special Interest Group):
http://sscale.org/988/volume-2...diesel-first-look-2/
Carl Tuveson's American Flyer website:
http://www.tuveson.com/sd70/af_sd.htm
Rusty
GP7/9, RS-3, etc. would be most welcome even if they've beem done before by other companies.
