Hi gang:
As many of you are aware, my club (Barrie Allandale Railroad Modellers) is in the process of designing and building a new permanent layout. We have decided to include a turntable and we want it to be able to accommodate the really big steam locomotives.
I have a few questions:
- One of the club members has suggested that we need a 140' turntable. Does it have to be that big to accommodate a UP Big Boy (4-8-8-4?).
- I know that Walthers offers 130' turntables but I have also read that they aren't that great. I know the Walthers 90' kits were pretty bad - I built one, but I made a whole bunch of changes so mine runs like a top. I paid peanuts for the 90' kit. I don't want to spend $350+ for an assembled version if I have to rebuild it from the start.
- I know that CMR offers turntable kits up to 135'. Their prices seem to be reasonable. Any experience with them?
Does anybody else make kits or plans for a large HO scale turntable?
Thanks,
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
Dave,
Diamond Scale also offers turntables maxing out at 135'. Haven't built a big one, although I'm very happy with my 75' one which has been in service more than a decade now.
I suspect that a 135' will work with Big Boys. The idea that 140' is needed may have to do with measuring overall length, when it's really the wheelbase that is the determining factor and somewhat less than the overal length.
Mike Lehman
Urbana, IL
I'm almost sure the larger Walthers one will fit the Big Boy. I have one still unused but I hope so as I plan on using it on my new layout.
I believe I heard some rumors that the early DCC model of these had some track alignment problems (electrical or programing?), but I don't think they had any mechanical programs?
Brian
My Layout Plan
Interesting new Plan Consideration
The Big Boy has a max. wheelbase of 123'-6.5'' but that might differ from the model's measures.
So it will fit on a 130 ft turntable but you have to watch for the overhang as it is 132 ft long.Regards, Volker
Edit: Custom Model Railroads offers a 135' turntable plus motor kit. Indexing isn't included I think.
I will briefly pass along my experience with the Walthers 130' model #2850 turntable. Spent two years trying to get this to index reliably, and not skip teeth in a 2-3 inch area of the gear track. Extreme care building level benchwork to the point of using lasers to get everything just right and this TT would not work reliably. This was to be an addition to a large layout, 900' plus of track that has been installed for nearly 30 years. Maximum frustration level was reached December 2016......TT removed, benchwork completely removed, and two partially built roundhouse structures put back in boxes along with TT. Nearly $600 and countless hours of work for nothing. I've chalked it up too experience and moved on. TT and structures now reside under the benchwork, final disposition undecided. As a sidebar concerning Walthers.......received 7 SD70ace diesels for Christmas last year and had to repair everyone of them, preorded 2 ES44AC diesels January 2016 and still waiting for a couple of average DC locomotives that are now expected November 2017??? Emailed Walthers to express my dissatisfaction. Received reply stating my concerns will be forwarded to the appropriate people several months ago and it ended there. This has been my actual experience.......draw your own conclusions and choose wisely before purchasing there products.
Howard Zane has at least 4 turntables I can say at least 2 are walthers a 90 and 130' He runs them all with MRC DC throttles and it's no problem at all to line up the rails. Maybe it's not the most elegant solution, but it's plug and play and the power packs are cheap enough on ebay
Henry
COB Potomac & Northern
Shenandoah Valley
After following your earlier TT thread, all I can say here is that you are the right guy to be taking care of this for the club
Guy
see stuff at: the Willoughby Line Site
So you are saying that Howard lines them up by eye, rather than some sort of indexing?
I built my own first turntable I installed on my Atlas plan 'Central Midland' layout. At first I was just going to apply a manual rotation gear and flexible shaft to it, but decided to motorize it just to see if i could. I used a big gear reduction motor and ran it with a varible-speed DC transformer. Worked just fine, but still had a little problem getting tracks lined up precisely as you need to view them all from several angles.
My turntable was not quite long enough to fit my Big boy, so I just provided a straight thru storage track for that particular engine.
BTW I am again considering the simplicity of a manually operated turntable on my new layout, particularly as it will be on a lower shelf/deck pretty close to the edge of the blob that will house it.....ahhh simplicity
You can find gear reduction 12 volt motors pretty cheap. For example
http://www.ebay.com/itm/DC-12V-14RPM-2-Wires-Electric-Geared-Box-Reduction-Motor-US-SELLER-/263145794668
This is a surplus electronics store I used to buy mail-order from
Allelectronicshttp://www.allelectronics.com/category/400/motors/1.html
According to http://steamlocomotive.com/misc/largest.php the locomotives longer than 130' with tender are the Big Boy, C&O's M1 turbine, N&W's Jawn Henry turbine, and PRR S1.
The big turbines are probably a lost cause to fit on a turntable, but digging into the specs for the Big Boy and the S1 the actual wheelbases with tenders are 117'7" and 123'9" respectively. Even with longer than prototypical engines due to extra drawbar space, 130' should be enough to turn them, although they would still overhang the ends.
Here's a video I just found of a Big Boy fitting on a Walthers 130' turntable: https://www.youtube.com/watch?v=UoyvaI7xk_E
Our club layout has 2 turntables, the first versioon of the Walthers 130' with indexing, and the other one is I think a Dimond Scales model someone built, about 110' based on how the larger locos look on it, which is driven by a rather crude motor with a rubber roller and spring, controlled with an old home built transistor throttle.
Which one actually gets used during shows and always works? If you said the one with the crude DC drive, you would be the winner. The Walthers one to my knowledge has NEVER worked. I spent significant time one day messing with it trying to get it to work, to no avail. Same with the Walthers transfer table in the engine facility. I managed to get a littel motion out of the transfer table but it would never run from one end to the other or home itself to allow programming. I gave up. My new layout will have a turntable, it will be either a Diamond Scale or CMR, with a simple non-indexed drive. It will be right near the front like the one is on the club layout so it will be super easy to line by eye instead of relying on some precision mechanical and electronic components to for repeatable automatic stops. Trying to build a drive with practically no backlash attached to wood framing which WILL move with environmental changes - no thanks.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks ckape:
The video shows that the Walthers 130' turntables can probably be made to operate smoothly. This is a Walthers 90' turntable built from a kit which works great! The 90' kits are garbage, but with a little ingenuity they can be made to operate smoothly and reliably. Here's mine in action:
I replaced the pit rail wheels with some spare brass wheels leftover from a Grandt Line box cab kit, and I added brass bearings to the main shaft. The biggest issue was cleaning the flash from the large drive gear. That took a lot of time and patience, and I had to do it a couple of times before I got the gear totally clean.
RR_MelI built my own indexing system but I can operate it manually also within 1/64” by eyeball using a DPDT momentary toggle switch.
.
1/64" is about 0.015", which should be plenty close to run on and off with no issues. Sounds good to me.
Every turntable I have see run with an indexing system has been frustrating. Everyone I have seen that was lined up by eye has worked very well.
Mine will use eyeball indexing!
-Kevin
Living the dream.
SeeYou190Every turntable I have see run with an indexing system has been frustrating. Everyone I have seen that was lined up by eye has worked very well.
I've got 4 turntables, all HOn3 gauge. Two index and two don't. They all work well for me.
My first was a converted Atlas TT. The Geneva motion indexing is limited in the number on-off finger track locations, but is dead accurate. My 75' Diamond Scale has a New York Railway Supply drive and it's also dead accurate. If you bump it and upset things, all you need do is reset the primary track and that sets everything back to where it was without needing to do a full reprogramming. There are no sensors, etc, it's all internal to the drive motor, so very uncomplicated as a system.
My other two are manual, but I don't align by eye so much as by touch, since my fingertip can differentiate better than my sight can these days.
Due to their locations away from the layout edge, indexing is virtually a necessity for the two indexed TTs. Yes, some patience is required in setting both of them up, but once dialed in they work well and require very little attention. In fact, the Atlas is under a snowshed and I can't even see it when its working, just the top of the boiler through a vent opening to let you see it's turning. The loco drives in and comes back out turned with nary a complaint.
That is quite the layout you have there Mike. Got a link to more photos, info?
Thank you everyone for all the information and suggestions.
Well, for the record, I bought a Walthers 90' turntable last year, factory assembled. It is indexed and it works like a charm. I do need to re-calibrate it from time to time, but its just a matter of pushing one button. The only issue I had was with the instructions. It took me a while to notice that the ones that came with the kit were missing 2 pages... After getting the PDF from the Web, I was succesful programming it. It runs very well. I understand that the earlier kits were more problematic.
Simon
snjroyWell, for the record, I bought a Walthers 90' turntable last year, factory assembled. It is indexed and it works like a charm.
Hi Simon:
Sounds like Walthers smartened up about the quality of their turntables. When I was working on my 90' kit several people suggested scrapping the mechanism completely. I was able to save it, but it took a lot of work. I'm glad yours operates properly.
The kit has always had issues, no idea if they ever fixed them, but I guess it became obvious when they used it as the bases of the fully built and indexed version. Most of the kit issues are because of design flawas. Most of the issues with the built up and indexed one are because it is rather finicky and delicate. Since all the control is throough the bridge, the slightest speck of ballast or other material on the pit 'rail' gear is likely to cause issues. And the mounting needs to be secure and not flex, it's easy to bind up the bridge . The two don't share the same issues. Mechanically, the built up one is pretty solid. The kit needs help.
AAA PRECISION TURNTABLES also makes HO turntables.
I know nothing about them other than I know a couple of O-scalers that have used them and liked them.
Good luck.
Edit ... I now see that you were asking for kits or plans. So, my info is not applicable.
Our club has had good experience with the (built) Walther's 130' TT. We line it up by eye. I have also seen the AAA HO turntable working at the Springfield show...it is pricey but very impressive. They provide not only the TT but the milled Aluminum base. My vote at the club was for the AAA..but the cheapskates prevailed.
JimLAAA PRECISION TURNTABLES also makes HO turntables.
JimLEdit ... I now see that you were asking for kits or plans. So, my info is not applicable.
Hi Jim:
Thanks for the lead. Actually we are open to either possibility. The cost is a bit sobering for either kits or built ups so we want to try to do this as economically as possible. Of course, cheaper often isn't better and we do want the thing to work properly.
I ended up building my own turntable for my layout (HERE). Basically I utilized Atlas bridge components for the rotating center span. The track and walkway portions came from the bases of Atlas (Roco) curved cord bridges, and these were rigidly mounted onto upside down plate girder bridge sections. Made a wonderfull rigid turntable bridge with wooden walks and handrails on the either side. I glued a spindle from an old 78rpm record player audio turntable onto the underside of this turntable bridge, and this spindle could be pluged into the original record player turntable located under the base pit, and the drive was accomplished with a rubber wheel sprung against the outer rim of the record player turntable. I was considering making a few of these turntables projects for resale, so I experimented with two different 'pit' styles. Both were aluminum pans that just fit the width of the 2 Atlas bridge section end-on-end. One pan was more shallow that the other for a turntable bridge that would consist of just the curved cord sections. The other pan was much deeper to accomodated the thicker turntable bridge with girder bridge sections added. It would just barely accomodate the longest loco, a Union Pacific BigBoy
That would be a very productive engine servicing facility, turning the locooos at 78 RPM!
(yes I know you didn't just use the original record player motor as-is)
The upper portions of the turntable deck were two sections of a Roco Curved Cord Bridge. They were glued onto 2 sections of bridge sections by Atlas mounted upside down.The rail around the perimeter of the baking pan pit was Atlas flexible track cut down the middle between the rails.
I've got some more photos, but not with me at this time.
Hi railandsail:
Unfortunately your pictures in the link you posted have been bitten by the Photobucket bug! They don't show up anymore.
Scratch building a turntable is a definite possibility. I like your idea of spliiting Atlas flex track in two to form the pit rail.
Are you sure that one photo did not show up? I still see it.
I took two of these Atlas Plate Girder bridges and turned them upside down to make a good stiff backbone to the turntable deck...
Then I used these deck portions of the Atlas Curved Cord Bridges to form the top of my turntable deck...
I even gave thoughts to just utilizing the entire curved cord bridge as the turntable deck,...not exactly prototypical but would make an interesting turntable.
Besides there were lots of 'truss supported' turntable decks in rural and wood cutting areas of the USA.