7mm/ft O scale 75ft turntable

75ft O scale (7mm/ft scale) turntable kit.

If you model in the UK then this kit is great for those "northern powerhouse" pacific steamers.  LNER A3's and A4s that ran out of Doncaster, or maybe a LMS Princess from Crewe works, this turntable kit will tick the box for you.

If you model in Germany, and need to turn your beautiful O scale German BR class 50 2-10-0 then this 23m Drehsheibe is just for you!

The kit is a stretched version of my 65ft turntable. It picks up generic features found across the UK and Germany, rather than focusing on a particular prototype.

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

75ft (23m) 7mm/ft bridge length = 525mm

bridge track deck width = 47mm

deck width between handrails = 91mm

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.

"El cheapo"  The 0.6rpm motor I released the kit with will turn the bridge just fine with the free-running 28mm wheels. BUT....its a very cheap motor. It has backlash. It has no lock when the motor has stopped. That means the motor will not hold the bridge still. its possible to add some 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 I'd say its worth a try.

GREENWOOD MODEL RAILWAY PRODUCTS. manual motor. Mike Greenwood now has an adapter plate for Kitwood Hill turntables which allows you to use his turntable drive systems. This is based around a stepper motor and 3 toothed belt reduction. I have the manual control version. it is a quality-built ready-assembled unit and runs really smooth. The manual control version is with simple a push button. You will have to order the unit from Mike. (£165 for the manual system as I type this) https://greenwoodmodelrailwayproducts.co.uk/

ADM Indexing system  Alistair at ADM retired in December and these most excellent drives are no longer available.  If you pick one up second hand I do have an adapter for it.

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: chairs for code 124 bullhead rail is included in UK and Oz orders ONLY. But the rail is no longer included. Use Peco. (code124 is no good for German locomotives. You will need to supply your own taller "Lenz" code 148 rail and chairs .) 

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 9mm 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 PCB sleepers 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.