US O scale 82ft turntable

82ft US O scale (1/48th) bow girder turntable kit.

Can be built with 2 rail, 3 rail or dual gauge.

Based on a Canadian Pacific design - in particular the turntable at Pembroke, Ontario, these bow girder style turntables were also found throughout the USA.

82ft is long enough for a standard gauge Baldwin 2-8-0 with tender which is the largest loco what I use it for.

Assembly is straightforward with step by step instructions with many photos. No need for clever solder skills - it really is for the "average" modeller.

This kit is for modellers who want something that will not look out of place and is simple to put together.

 bridge dimensions

82ft 1/48 scale bridge length = 20.5" (525mm)

deck width between bow girders = 3.5" (90mm)

Pit dimensions:

Outer rim = 558mm

hole required = 548mm

pit depth:  31mm at centre, 25mm at edge

Drive train options:-

Hand from heaven!  The most basic turning is hand from above. 100% foolproof, 100% simple.  This is what I use on my dual gauge module.

"El cheapo"  The 0.6rpm motor I released the kit with will turn the bridge just fine with the free-running wheels. BUT....its a very cheap motor. It has backlash. It has no lock when the motor has stopped. That means the cheap motor will not hold the bridge still by itslelf. its possible to add enough friction at the shaft to hold the bridge in place. This is why I have removed the cheap motor from the options, but the mounting for it and shaft adapter is still included in the kit and the motors are available on ebay. Search "0.6RPM Motor gearbox", or "GW370 motor gearbox" on ebay.  For the price of a couple of beers its worth a try.

NYRS turntable drive can be used (with indexing system). Jack at NYRS is familiar with my turntables and can sort you out a simple interface

DCC or DC. Like all KHM turntables can be used with either system. The track power PCB connection rings are continuous so there are no disconnects to DCC decoders with sound as the bridge turns. The contact plungers are 6A rated quality items from the electronics industry. Polarity can be handled with a DCC reversing module or a simple DPDT switch for DC.

Primary shaft turning plate: the heart of all KHM turntables and now proven design. This is a jig-built, ready-assembled item with the 4mm primary shaft, pinned and epoxied into a milled brass section. She ain't slipping!!

Assembly and construction:-

Bridge is made of laser cut ply of various types and thickness with hardwood decking. Glued together with step by step photo instructions. Not hard. Novices have built my turntables!

Bridge track is not included. The deck will take 2 rail, 3 rail or dual gauge (like mine) but you will have to supply your own

Pit is laser cut 3mm and 4mm ply. Because of the weight of locos it is best to support the turntable from below, rather than the rim (unlike other KHM turntables)

While the kit will make up a whole pit with base , because of the size it is very strongly recommended to fix an additional flat, rigid 3/8" ply sheet to the underside to maintain rigidity. This isn't in the kit because that would weigh far too much and be too big to ship!

Ring rail:  Code 100 (included) is soldered to copper clad ties and a simple jig helps you get it circular and set in the right place. All KHM turntables use the method and its well proven over the years. Its simple, even for novice solderers.

bridge wheels: Now 3D printed Nylon with ball-race bearings. They are wide enough to be forgiving of "assembly tolerance" of the ring rail.

INSTRUCTIONS ARE NOT PRINTED. This would be high cost, and heavier to ship. This way I can include very many photos. The PDF files are emailed to you when the kit is shipped. If you want to see instructions to help your purchasing decision then I happy to send without obligation. Electrons are free!  Just contact me on the contact page.