Atlas F7 Pre-Order Pulling Power

You might be able to find a product review from their F3's in the OGR archives or even the Atlas website. It maybe an old review, but the drives & weight will be the same.

How many cars do you want to pull?

update: product review from 2004 Model Railroad News, GP35 (basically the same drive as the F unit's) pulled 28 mixed freight cars on level track with no issues.

You have to remember though, it may pull the train no problem, but you could be tearing up the traction tires and not even know it, unit it's too late

15 - 20 would do it.

2-powered 3-rail Atlas F7's should be able to handle that, easily.  I am assuming that the F7's will be mechanically identical to the F3's.      

However, I am also assuming that the freight cars were made from 1987 on for the most part.

Here is a video link of my Northern Pacific F3 A-B-B-A.  The two A units are powered, the B units are dummies, and they are real boat anchors.  This train is about the limit of what can be pulled with two locomotives on O-72 to O-90 curves.  If the B units were not on there, you could probably do another five cars.  The train had 24 cars plus the brain box on the end. 

Regards,GNNPNUT

For what it's worth, I have learned from statements posted over on the 2-Rail SCALE Forum, that all the Atlas O "dummy" units come with the full set of gearing in the truck assemblies. That must be why they add so much drag to the locomotive consist. If one was to remove all the gearing from the "dummies", I'll bet they would then roll pretty smoothly.

Here's a quick shot of my unpowered A unit. I suppose one could take out the idler gears as they seem to be held in with c clips but my unit rolls along pretty smoothly And coasts with a little push. It does weigh quite a bit due to the cast frame, probably about 4-5 scale cars' worth as mentioned above.

Norm, did you remove the pickup rollers on the dummy?  On my B units, they have pickup rollers on them, didn't see an easy way to remove, never got around to digging into it further.

Regards, 

Jerry

Jerry, yes, I pulled them out when I fixed the pilot. They are screwed in from over the top of the truck assembly. I don't even think they had leads on them, I think I had to solder in my own when I had a board in there to control the electrocoupler.

Got to LOVE the "optional" fixed pilots that Atlas includes with there "A" units.  Is that what you used here, or is this your handy-work?

A step ahead of Lionel and MTH.  They have been offering this "owner installation" option for years and no other manufacturer has caught on.  

What I find even MORE TROUBLING is that one still insist on unbilical cords as a method to control trailing powered units.  HELLO... last time I looked at the calendar it read 2015.

What makes them draggy is not the gears but the pickup mechanism.
 Atlas uses a sprung pickup on one side of the trucks to obtain electricity from
 the wheels. These are present in F dummy units to feed the light board. Here are
 some pictures of the mechanism and the inside of a 2-rail dummy F3,
 two wheels in each truck have this sprung pick up. If not needed, once removed
 and the gears greased the unit it runs pretty decently!

What makes them draggy is not the gears but the pickup mechanism.
 Atlas uses a sprung pickup on one side of the trucks to obtain electricity from
 the wheels. These are present in F dummy units to feed the light board. Here are
 some pictures of the mechanism and the inside of a 2-rail dummy F3,
 two wheels in each truck have this sprung pick up. If not needed, once removed
 and the gears greased the unit it runs pretty decently!

That applies to 2-Rail models only. The Atlas 3-Rail models have center rail roller pickups, no mater whether powered or dummy. 

Jim, the fixed pilots are an Atlas F2/F3 feature in the 3 rail models. You get an extra set of pilots and a full set of scale couplers along with the rear coupler mounting boxes. You have to grind off the electrocoupler mounts front and rear so it's not really reversible/interchangeable.

Thanks Norm.  Just as I thought when I posted:  Got to LOVE the "optional" fixed pilots that Atlas includes with there "A" units.

And so... Atlas remains a step ahead of the competition.

I have 2 Atlas B units.  They did not roll easily.  I removed the pick up roller, gears and replaced the wheel sets that had traction tires with sets without (I ordered them from Atlas).  This few things made a big difference in the rolling resistance.

T4TT -

Sounds like excellent advice.  Do you have a part number and price for the replacement wheel sets?  I need a pair for my non-powered GP60.  I have searched the Atlas-O parts site and can not find these wheel sets.

Thanks.

Hi Jim,

The part number for the Atlas non grooved/non traction tire wheelset is 2005171.  They were 4.95 each.  It cost me $24.80 for 4 axles and $5 shipping.

Take Jim, I enjoy your posts.

T4TT,

Thank you.  Were you able to order via the AtlasO website or did you have to call it in?

As I mentioned earlier, I searched the site but could not find the part.  I also tried to enter this part number into the "search"  window w/o any luck.

Jim