Hi, I dont have a layout right now but I’ve been working on some projects for an anticipated move and a future layout. I am scratchbuilding a turntable and would like some comments or suggestions (or tell me I’m crazy dont do it) Ive’ read alot about the walthers (heljan) units allthough I havent seen one. I thought about it but I’m too cheap and what fun would that be, Anyway the problem seems to be with the pits. I have built an awsome pit and I have constructed the drive unit. I am not interested in indexing and I am moving on to the bridge. My question is should I modify a walthers (heljan) bridge or scratchbuild it. How deep are the walthers pits and what does the center pivot look like? I know there are different models. I am interested in pit rail and center pivot power pick up. I also liked the through girder type like the lackawanna TT at Port Morris N.J. (its different) which was in RMC awhile back but this type gets real interesting with the bogies. I’m looking for ideas and comments and let me know if you need more info. Thanks MARK
I have scratchbuilt a turntable in N scale once. I hope you are mechanicaly inclined. The measurments and centers for drilling will need to be very close tolerances.
Scratchbuild it. I used a piece of wood block for the base structure part of my bridge and then used evergreen styrene to make the prototype sides and glued them to the wood block.
It doesn’t matter. Don’t make your model from a model. Do some research on the Internet and make it as deep as the real ones were. As to the center pivot, you can use a brass tube in a brass tube bearing. You just need a firm structure for the bottom of the pit to hold the bearing. You can epoxy the bearing in. Mine was 3/4 inch plywood.
As mentioned in this month’s Model Railroader, a stereo plug makes an excellent pivot that can also carry track power.
There have been an amazing number of turntable bridge designs, so your sly and cunning maneuver would be to hunt up photos of turntables used by your prototype railroad, or the one you freelance around. Even that may prove to be a large number - my prototype ranged from a transplanted deck girder bridge in an incredibly deep pit to through girder designs in pits about as deep as a soup bowl, with the carrier wheels outboard of the girder riding on a ring rail barely below the bases of the running rails.
One good thing about researching and then scratchbuilding - you don’t end up with a TT just like everyone else’s.
Chuck (modeling Central Japan in September, 1964 - with 2 dis-similar turntables)
As allways, thanks for the info and ideas. My entire turntable pit was (with the help of a friend) milled out of a solid piece of aluminum. It was then finish cut on a large lathe so it is absolutely precise. I have a bronze bearing pressed in the center and a 3/16 steel shaft to eventually turn the center. The drive is a 12 volt DC gear motor (about 4 rpm) connected to an additional gear box further reducing the speed. I made this myself out of brass gears, steel shafts, and bronze bearings. It is an open design and easily dissassembled to change gears if I find its too slow. I think right now you can go make yourself a cup of coffee while your engine is turning. I think the commercial turntables look good and I was kind of wondering if its better to buy one for the nice rivets and all. but my goal is one that runs great and lasts a long time without problems. MARK
Speaker rings are useful when scratchbuilding a turntable. You can get them in different sizes and they make a good form for the pit wall.
And note what the author says under the “REFLECTIONS” section…
Mark,
I have scratchbuilt one turntable and am finishing up another. I would suggest that you check out Diamond scale for the bridge trucks. Second suggestion is that you obtain scale drawings of the prototype that you prefer and scratchbuild the bridge from them. I agree with what Craig says in the aforementioned “relections” section. Building a scale operating turntable from scratch is not an easy endeavor.
Good luck,
Guy
I built a Diamond Scale turntable for a friend many years ago, and, while it works well, I was very disappointed in the kit: the pit was out-of-round and I wasn’t particularly impressed that so much fiddling was required to make it right. They may have improved them in the intervening years, though.
Wayne