A bit late but here goes.
I don’t have any Stewarts F’s, all my diesels are PAs or E7s and all are AB with a brass drawbar connected with Kadee’s one on each end. All my road diesels are super heavy (25oz to 33oz) and need the brass drawbar. They all have 8oz to 10oz of drawbar each. I use a 2mm screw to hold the drawbars and never have any problem. I simply lay them on their sides and remove one screw, I also wire them together with polarized micro connectors that easily disconnect. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
Yes you could get FTs as an A-A set running back to back connected by drawbar. The A-B sets were also connected back to back; as I mentioned earlier, unlike later F units the FTs trucks were offset toward the back so there was an overhang in the front with the rear trucks very close to that end.
BTW an A-A set, or an A-B-A set using the FTSB "short booster" between two A units, had to be freight-only. Only the standard FT B unit had room for a steam generator and water tanks, in the end of the B unit where on an A unit the cab would be.
Autonerd Late reply: I don't think FTs ever would have run AA --
Late reply: I don't think FTs ever would have run AA --
This is an incorrect assumption. Steve Sandifer's article on the FTs on the web site of the Santa Fe Historical Society
https://sfrhms.org/wp-content/uploads/2019/02/ft-_locos.pdf
refers to several pics of FT AA combos (or "LL" in Santa Fe speak), including
402L-414L as A-A Emporia, KS - St. Joseph, MO and Emporia - Wellington, 1954
407L-429L A-A Emporia, KS - Superior, NE, 1952
(Sorry, I cannot access the pics.)
Of course, it should be noted that all Santa Fe FTs had couplers between A and B units, not drawbars, making it easier to build an A-A consist.
davefrSimply because I'd like ease/flexibility to reconfiguring the consist from ABBA to ABA and maybe even AA.
Late reply: I don't think FTs ever would have run AA -- I believe they were AB sets from the factory, though there were some ABAs and ABBBs. Basically you'd buy a single 2700 hp locomotive from EMD, and you'd get an AB set.
If you're running long trains or steep grades, I would consider keeping the powered units together (so either an AB powered or even BB powered).
Well the solution was 2 packs of Kadee #38's and 2 packs of Kaydee #5's and now everything can connect to everything else in any combination. The #38's needed to be modified to fit but they work fine.
A couple of thoughts.
You could try making a two-piece drawbar that used neodymium magnets to keep them together. Maybe an additional pin and socket would have to be employed or, perhaps two pieces of telescoping Evergreen square tubing with the magnets embedded and epoxied inside? If the lead and trailing A units are pulling together there wouldn't be much force to pull the magnets apart.
OR perhaps you could modify one of those safety snap devices that many neck lanyards use? They seem to click together with a pretty strong grip but can be separated by squeezing a tab or some such device.
Cheers, Ed
Hello All,
davefrI've test run the ABA's on DC and there's been no issue with mismatched speed. They run great.
If you are running in DC that is great news.
davefr...Beside(s) that, it's quite a handful handling a string of attached ABBA's off rail.
I completely understand. I have little staging space for the 4-unit consist of GP40s on my 4'x8' pike.
davefrI'd like ease/flexibility to reconfiguring the consist from ABBA to ABA and maybe even AA.
Unfortunately, drawbars don't allow for the flexibility you are seeking. Couplers would be the way to go.
Hope this helps.
"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"
Yes Santa Fe did get EMD to jerry-rig up a coupler assembly that could be added to FT A and B units. Remember unlike later F units, the trucks of the FTs were offset so only the end with the long overhang were designed for couplers.
Some of the railroads that used the A-B FTs with an F2 or F3 A unit may have numbered the added A unit to match the FTs, so they were like 343A-B-C or something, due to the union issues. However as I recall that issue was resolved fairly soon - by the end of the forties?
wjstixSince FT B-units weren't designed to have couplers at both ends, and not all railroads wanted to buy FTSB units to have drawbar connected A-B-A sets, a number of railroads bought single 1350 HP F2 or later 1500 HP F3 A units after WW2. That way they could run an FTA-FTB+F3 set which would have 4200 HP - "just right", but could still combine two FTA-B sets for 5400 HP when needed for longer trains.
Much of any attempt to use additional A units to get 'bidirectional' rightsized consists would not have been done before the MU-locomotive issue had been resolved with the unions, as one of the claims was that each unit with a cab and separable by couplers should count as a separate locomotive for crew allocations. So the quoted combination would require two assigned crews to be paid in full to operate, with this presumably retroactively billed to the date the combination was put in service were the decision on MUed consists to have gone the other way in the '40s.
As I further recall, this is why ATSF went into A-B-B-B consists for an appreciable part of its early-postwar F-unit fleet.
davefr Beside that, it's quite a handful handling a string of attached ABBA's off rail.
As I mentioned, having all four connected by drawbars is not prototypical. You would have two A-B sets with the A and B units connected with drawbars. Two A-B sets would join together back to back using regular couplers. Picking up an A-B set of F's in HO isn't hard.
Real railroads during WW2 found a problem with that set-up. A typical mainline freight of the era needed about 4000 horsepower, like a fairly large steam engine (2-8-4 for example) would produce. FTs were 1350 HP each, so one A-B set of FTs were 2700 HP - not enough power. An A-B+B-A set was 5400 HP - way too much power.
Since FT B-units weren't designed to have couplers at both ends, and not all railroads wanted to buy FTSB units to have drawbar connected A-B-A sets, a number of railroads bought single 1350 HP F2 or later 1500 HP F3 A units after WW2. That way they could run an FTA-FTB+F3 set which would have 4200 HP - "just right", but could still combine two FTA-B sets for 5400 HP when needed for longer trains.
I have operated my Stewart ABBA for many years . I use the drawbar between each A and B. Between the B units I have Kadee couplers . The front of each A unit has a Kadee coupler.
I have had no problems with this arrangement. If you have tight radius curves, you can easily make longer draw bars.
Note: FT's were delivered to various railroads from EMD with a drawbar between each A unit and B unit.
GARRY
HEARTLAND DIVISION, CB&Q RR
EVERYWHERE LOST; WE HUSTLE OUR CABOOSE FOR YOU
Well, if that's what you want then that's what you want. However, the Kadee #35 conversion kit does work well and is made for the rear of the Stewart FT B-unit chassis, as well as the pilot of the A-unit:
https://www.kadee.com/ho-scale-couplers-c-272_230_231/35-30series-couplers-short-overset-ho-p-269.htm
And I don't bother with the supplied coupler; preferring to use a Kadee #58 with the #35 gearbox. The larger Kadee #5 would work, as well.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Thanks everyone for the replies. I think my only solution is two short drawbars pegged together or maybe a peg in one end of each locomotive chassis and a drawbar in the other. This illustrates what little room I have to work with. A Stewart drawbar just barely clears.
Overmod...an important factor in this discussion may be whether he's going to run these DCC and, if so, how good his consisting will be.
DC vs. DCC can make a huge difference in how this consist will perform. If the DC units don't "play well together" it will be a struggle no matter how the units are MUd.
With DCC they can be speed matched- -depending on the decoder(s).
My question to the OP is why do/will you need to break the consist?
If you can answer these question the great folks on these forums can help better answer you questions.
If I take 2 powered Stewart F units, consist them with a pair of B unit dummies in between, if I use the same brand decoder in both - there won't be any consisting issues. ALmost certainly won't even have to fool around with speed matching them. Even if they have BEMF. I've got completely mixed sets (different brand locos, different decoders in them) which had had absolutely no speed table settings done. They run perfectly fine. It's even easier when they are both the same brand loco. People were doing this with DC long before there was DCC. DCC does not change that. Just because you CAN spend hours tweaking perfect lockstep response doesn't mean you HAVE to.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I replaced the screw on the front of the B unit with a longer-shank screw with the head cut off and made it a drawbar pin such as in Wayne's example.
The Stewart FTs came with several lengths of drawbars but they all broke after a while. I bought replacements from State Tool & Die.
There's no room at the front of the B unit for a coupler.
Good Luck, Ed
Yes, as has been talked about already, making them two A-B drawbar connected sets would make the most sense. Remember that the real FTs were designed to run as an A-B set connected with a drawbar. There was also an FTSB (Short Booster) that could be connected between two A units with drawbars, making an A-B-A drawbar connected set. Unfortunately no one has ever made an FTSB in HO (except maybe in brass?) .
It's possible some railroad(s) ran A-B-B-A sets all connected soley by drawbars, but if so, it would have been very rare. An A-B set of F's fit on most late steam-era turntables and in corresponding roundhouse stalls - remember that early in the diesel era railroads continued to use existing roundhouses for maintenance until dedicated diesel engine houses could be built.
Later F units, starting with the F2, could have couplers at both ends of A and B units - although many railroads did (at least at first) continue to use drawbars between A and B units.
Back in the DC era, I knew several modelers who used a steam loco / tender drawbar such that Wayne pictured. It worked well for the time. I tried it for a while, it worked, but I really like the flexibility of couplers on both ends of a unit. I did power the B and dummy the A; primarily to put a cab interior in the A unit.
I don't know if the curve in the picture is representative, but an important factor in this discussion may be whether he's going to run these DCC and, if so, how good his consisting will be.
Having two powered units flanking a couple of dummies is giving all sorts of opportunity to kicking out the middle if consistent tractive effort isn't kept on all the intermediate connections at all speeds, including momentum coasting. I would argue that any intermediate drawbar or coupler alignment and centering choice be done with this in mind.
Ideally I'd think that if he carefully speed-matches the A units the 'bidirectional' resulting consist should work OK in either direction. Does he need careful reduction of 'slack' in his drawbar holes, if he sticks with drawbars, or might he benefit from spring centering of some kind with drawbars?
My hood units, Athearn blue box F7s and Proto 2000 Alco FA and FB units just go together with Kadee couplers. All the locomotives, both powered and dummy, have coupler boxes on both ends that can take Kadee couplers, not #5's but Kadee recommended couplers for those products. What does the Kadee "what-fits-what" list recommend for your diesels?
You can buy or make drawbars to fit anything. Downside is you need a screw driver to get the units apart. Couplers are more convenient.
David Starr www.newsnorthwoods.blogspot.com
Why not just have the draw bar between both sets of A-Bs and Kadee couplers between the two B units? Then you are just connecting one FT A-B to another FT A-B via couplers. This also allows you the freedom to use each FT A-B set separately.
I used the Kadee #450 conversion kit to add gearbox & couplers to the ends of the B-units. Even with a #58 scale coupler, it works great.
The #35 works on the rear of the A units.
But what I would do is someone claser to prototype practice - each A-B set is drawbar coupled, and then the B's have Kadees on the rear, so the two A-B sets can be coupled together to make your A-B-B-A set. I have my FT A-B connected with the drawbar, but my other F units all have couplers, so I can replicate mixed consists with FT, F3, and F7 units as happened later once the drawbars mostly vanished.
to the Model Railroader Forums davefr!
davefr...Is there a drawbar attachment system that's easy to attach and detach. The only place for a Kaydee coupling is the front of A's and back of B's. Besides that I don't link it would work to well for this string of locomotives. I guess I'm looking for 2 piece drawbars that can be separated easy. Any ideas?
I'm guessing that there's no room for installing Kadees in draught gear boxes, although it might be possible to use short-shank Kadees without the draught gear, and install them with the screws used to hold the drawbars in place. Because the mounting hole in the coupler's shank is fairly large, I'd suggest bushing it with either plastic or brass tubing to eliminate any slop.
Another choice would be to do a drawbar set-up as used on most model steam locomotives, where the drawbar is screw-mounted to the locomotive, while the tender is fitted with a "peg" that fits into a hole at the rear of the drawbar...
You could make the pegs using either 3/32" piano wire or brass tubing of a similar diameter. This would allow you to at least be able to separate and pick up each unit individually.
Wayne
The Kadee #450 is for Stewart F units, but it does not fit the FTs, so do not try that one.
Can one ond of the drawbar be converted to a pin like on a brass tender-to-locomotiove configuration?
I do not own any FTs, so I cannot help much.
-Kevin
Living the dream.
I'd convert the drawbars to Kadees and be done with it. I don't recall the Kadee part #, but maybe someone else can help us out?
Mike Lehman
Urbana, IL
Hi Fellas,
I'm experimenting with a future layout and I'd like to use two Stewart FTA/B sets to create a FTA-FTB-FTB-FTA string with the two FTA's powered.
These locomotives use drawbars and screws between A's and B's and B's to B's This creates a long attached string to move around and somewht of a PIA to reconfigure.
Is there a drawbar attachment system that's easy to attach and detach. The only place for a Kaydee coupling is the front of A's and back of B's. Besides that I don't link it would work to well for this string of locomotives. I guess I'm looking for 2 piece drawbars that can be separated easy. Any ideas?
TIA