Stepper-motor turntable drive?

[JeffP]

Last year at Telford, I saw demonstrated, a superb turntable drive using a stepper motor and associated electronics.

I can neither find the leaflet I had, nor any mention of the beast on t'internet.

 

All I know is that it wasn't Metalsmiths, but was driving one of their turntables.

 

Can anyone point me at it, please?

[newbryford]

It may have been by one of the Liverpool Lime Street team. I know Jeff - who does the electronic stuff for LLS, was working on the possibility of making it commercially available. It may be worth posting on the LLS thread.

 

Cheers,

Mick

[nick_bastable]

look at a Ardunio to control a stepper motor the codes all written and a  set up can be had with motor ( if you can solder ) for under £20

[ozzyo]

Hello Jeff,

 

have a look on the tehnobots web site for stepper motors you can also get toothed drive-belts and pulleys. If your going to go along this route you want a motor with as many steps as possible. So if you start with a motor with 400 steps per rev. and use a 2;1 reduction you should end up with 800 steps at the T.T. and so on. 

 

OzzyO.

[Coombe Barton]

At Scaleforum i went to the Model Railway Developments stand http://www.emardee.org.uk and saw an indexing device for turntables. You may want to have a look, although I couldn't find it on their website. And i only saw it - don't have any other details.

[Michael Woolford]

Jeff,

 

As Mick said, it may be by the same guy who does all of the control systems for Liverpool Lime Street; Geoff Peters. I know he demonstrated at Telford and I think what you are looking for can be found on his website. If I am right you were posting on the LLS thread and asking about the turntable some time ago; I remember Steve put a link to the website and described the systems on the thread. 

 

http://www.rmweb.co.uk/community/index.php?/topic/33141-lime-street-station/page-13 

 

If you go to post 317 at the above link then you will find a description by Steve and a link to Geoff's website. Hopefully this is what you were looking at when you went to Telford.

 

Michael

[JeffP]

Thankyou one and all.

I'll follow those links.

Michael: I probably did ask for advice before, then forgot it as Metalsmiths had no turntables anyway......NOW I have one!

 

Thanks again.

 

The one from Liverpool Lime Street is a bust: none in stock, and no plans to make any more.

 

Back to the drawing board. I'm afraid my electronics knowledge stops at how a transistor works, so actually buying the parts and self-building may be a non-starter.

[JeffP]

Tried the Arduino site, I'm awaiting a response on their forums about how to control a motor. The link I got off there was for a motor etc and was only $4.76....sadly, the vendor refuses to ship to the UK.

 

I've also contacted Metalsmiths, who now list one, but with no details about how it's controlled. I want standalone, NOT from my computer.

[meil]

Try the MERG stepper motor controller. Designed for use with a turntable.

[steve fay]

Jeff,

I've used my turntable with the supplied belt drive system, its very controllable, I was talking to the guys on 83G and they use a toothed disc under the turntable driven by a worm and they line the track up by site. They said this system was the best they had used as the belt on the standard metal smith supplied one can stretch.

On RB I'm going to line up the turn table by site but to help I'm going to add a security camera directly over head in the ceiling and have a monitor up on the wall so I have a birds eye view over the turn table.

[nick_bastable]

quick look on that auction site throws up a  steppers with controllers for ardunio one @ sub £2 which is I think what I paid  and a build your own ardunio for less than  a £10

 

try the tutiorial http://arduino.cc/en/Reference/StepperConstructor

 

cant comment more on a turntable becuase having done the provisional work/bench test  i have yet to build the TT to see how it works in practice 

[CUTLER2579]

Jeff,

I think you were thinking of G.F.Controls. It was my intention to purchase one,but their website now states:-

Turntable Unit

 
These units are now out of stock.
There are currently no plans for any further production.

The G F Controls turntable operating unit has been made as a result of the frustrations the designers have found in properly indexing track alignment in the past.  This new unit is a very substantial engineering and electronics solution to the problem.

 

Regards,Unhappy Del.

[JeffP]

Yes, that's the one. I might try an email.

[CUTLER2579]

Jeff,

if you do e-mail them and get a positive response would you PM me and let me know please, as I was going to purchase one as well.

Regards,Derek.

[JeffP]

OK, some good news for me and bad for Derek.

 

I e-mailed them, got a response stating that they knew of one with a customer in the USA which was no longer required and had not been used, but had been upgraded by themselves.

 

I contacted him and after a bit of to-ing and fro-ing, we have done a deal. I have yet to pay for it, he has to e-mail me the deatils of a friend's bank in the UK the money can go into. He is standing carriage costs from the USA. I am waiting to hear from him, but he is 8 hours behind me.

 

The bad news is that no more are being made, although they still offer support for those in existence.

 

If I were you, Derek, I'd e-mail them asking if it's possible to put together a kit of parts and make one yourself? Or if they know of any others going spare.

 

Sorry for the bad news, Jeff.

[Simond]

Anyone got any recommendations for an O gauge turntable drive belt to connect the big Metalsmith mdf pulley to a motor?

 

Or has anyone got further experience of the Metalsmith drive belt?

 

Thx

Simon

[CUTLER2579]

Hello Jeff,

Thanks for your update. Just proves the old SAS adage -He who dares (does) in this case. Well done my friend I am very pleased for you.

Will get an e-mail off to them today and let you know how I get on.

Simon, at risk of upsetting my friend @ Metalsmith, have you considered replacing the drive with an ABC Turntable Drive Unit. (usual no connection thing.).  I have been considering this for some time.

 

 

All prices are inclusive of VAT at 20% - (Prices subject to change without notice.)

              We produce a worm & wheel turntable drive unit - size 110mm x 84.5mm using a motor with a 100:1 gearhead followed by our 120:1 worm drive giving a total reduction ratio of 12000:1 - with continuous running this equates to approximately 0.35rpm on 6v, 0.7rpm on 12v and 1.4rpm on 24v   Pricing for the complete unit is 55.00
Postage & packing 7.00

 

Now I got this from the "O" Gauge Guild website,but I have no experience of it. However they have a good name for gearboxes and this looks a well engineered bit of kit,especially at the price.

Regards.

[Simond]

Thanks Derek

 

Looked at Arduino website and I'm thinking stepper motor (with added benefit of option to do servo point motors - smaller and cheaper than tortoises)

 

I looked also at the Technobots website mentioned above and need to check that there is a belt long enough for the big mdf pulley. I think there is and so a couple of plastic teeth to make sure it doesn't slip, and a few quid for a stepper & toothed pulley and Robert's your mother's brother... Well, watch this space! And, more or less the same price as the abc unit (I love their loco gearboxes - nearly all my locos have them) so the benefit of automatic indexing is "free"!

 

I quite like the idea because I have quite a bit of a scratch built scale Stothert & Pitt 12t level luffing dockyard crane, and a couple of other goodies, all of which will benefit from me learning how to do this.

 

Of course, there's the nearly finished mostly scratch built 28xx, and a part built King, and the not-yet-started 1361 from last Christmas to do too, plus a PBV And a siphon to finish.... Message to self. Don't buy anything needing any work whatsoever at Reading!

 

Best

SD

[Blue Max]

At the Peterborough show today there was a company 'ADM Turntables' selling a very proffesional looking turntable system.

Contact details are Tel; 01933 411127 and e-mail; alastair@admturntables.co.uk

[polybear]

At the Peterborough show today there was a company 'ADM Turntables' selling a very proffesional looking turntable system.

Contact details are Tel; 01933 411127 and e-mail; alastair@admturntables.co.uk

 Seemed to work very well,  though very little detail on the turntable itself (standard PECO unit?).  Very little change out of 400 notes though 

 

polybear

[JeffP]

Not much out of £600 for the Metalsmith 7mm Ransomes and Rapier setup........

[Simond]

Progress!!!

 

Have received the Arduino and stepper motor, plus other bits & pieces. Soldered up the stepper driver without problems.

 

Initial playing with the examples provided and have managed to get speed and direction control of the motor. Next step (sorry) is to get position control sorted.

 

Still haven't got a drive belt. Any ideas welcome!

 

I'm very optimistic that this is going to work!

 

SD

[tender]

Funnily enough, I've been playing around with a Arduino plus stepper motor directly connected to a PECO turntable shaft today.

Initial results look promising, I've used a Hall effect device on the well and magnet on the bridge to provide a single index point and then am able to turn the bridge back and forth (180deg) just by counting steps. Have done this continuously for a good hour or so without loosing registration. Next step is to build a DCC interface for the Arduino and control the turntable with DCC accessory commands.

Ray.

[JeffP]

Interesting last two posts.

 

Keep us informed, please.

 

My GF Controls unit arrived from the States while I was working away. Just need to construct the turntable now, but have been told it needs to run like a sewing machine.....

[polybear]

This is an interesting thread - I'd be interested in how to use/program an Arduino also please; ideally I'd like to be able to control a stepper motor driving a turntable using perhaps some form of selector switch to choose which road is required etc.  I don't really want a laptop etc. hooked up all the time!

 

 

Many thanks.

polybear

 

p.s.  This site may be of interest to you (no connections etc.) for the PTC III Turntable Control System:

 

http://www.nyrs.com/overview.htm