Any Question Answered

[Caley Jim]

I've no experience of these motors, but it sounds to me that it was overheating and there was enough expansion to cause the armature to bind on the outer casing. The gap between the rotor and the magnets will be pretty small.

 

Jim

[Hendreladis]

Thanks guys

 

Jim's explanations seems credible. I'll bin the motor and put in a Lawton.

 

A

[Donw]

If there is binding which is slowing the motor or even a heavy load holding the speed down, then the fact that the voltage is higher than the design voltage means the back emf is much lower than the applied voltage causing the motor current to rise actually stalling would be worse. Most motors can tolerate a brief stall and can be design to safely stall but not if excessive voltage is applied.

 

Don

[RichardBenn]

Last night I blackened the faces of some Association Drop-In DMU wheels by applying Casey Super Blue using a cotton bud, then giving them a quick swish in water to rinse off the chemical and placing them on a piece of kitchen towel to dry. This morning they are covered in a light rust coloured powder.

 

It looks like the powder will rub off, but what did I do wrong? Too much Super Blue? Not enough rinsing? Wrong type of metal? These are the first drop in wheels I've blackened this way, but I've previously done turned wheels from several Dapol diesels with no ill effects.

 

Richard

[Izzy]

Are these the geared wheels for the power bogie or the pin-point split-axle ones, or both? The latter are all-steel on a muff while the former are steel on anodised aluminum axles. I'm afraid I haven't use Casey blue on either type at present, but it does react differently to being used on brass/nickel plated wheels ( mostly what Farish/Dapol wheels are). Can't work out why the rust type result unless there has been a reaction with the glue used on the power bogie types.

 

Izzy

[RichardBenn]

Both types. They've cleaned up fine and this morning there are no signs of it coming back. Thinking about it, I was surprised at how quickly it worked compared to the Dapol wheels so i suspect it needed more than a quick swish in water. Next time I'll dunk them for a while. Is water the best way to neutralise this stuff?

 

Thanks.

 

Richard.

[garethashenden]

Both types. They've cleaned up fine and this morning there are no signs of it coming back. Thinking about it, I was surprised at how quickly it worked compared to the Dapol wheels so i suspect it needed more than a quick swish in water. Next time I'll dunk them for a while. Is water the best way to neutralise this stuff?

 

Thanks.

 

Richard.

 

Water is the right thing to use, but don't let it sit on the steel. Rinse them off and then pat them dry right away.

[justin1985]

I've had this problem with normal Association wheels too. Either Birchwood Casey or Carr's followed by water and no matter how thoroughly I dry them off by hand (plus leave them in the sun etc) there has been a considerable layer of rust to scrape off. It worries me that this seems to accumulate in areas I can't get to to clean. I was kind of thinking I'd skip straight to painting in future.

 

Justin

[queensquare]

I use a sharpie permanent marker pen for this sort of thing - colour in the wheels!

 

Jerry

[RichardBenn]

Thanks for the replies - nice to know it's not just me.

 

I've used a Sharpie for other metal blackening (such as the visible bits of phosphor bronze on power bogies) but I wasn't sure whether it would look too "solid" on wheels. i will give it a go next time.

 

I do like the effect of blackened wheels. The only thing that looks nicer is blackened wheels after you have removed the rust that has appeared overnight which gives the effect that they are subtly weathered by brake dust. :-)

[Valentin]

Hello,

 

Would this type of rolling road be suitable for our models? If not, what do you recommend?

 

Regards,

[Wyvern]

I use a bachrus rolling road which is adjustable and so can be set to 9.42mm gauge. The one you have provided a link to is fixed to 9mm N Gauge so wouldn't be usable for 2mm fine scale.

[Wyvern]

You want the 40 series rollers which are linked to below;

 

http://www.digitrains.co.uk/manufacturers/bachrus.aspx

[Crosland]

Better price, and in stock, at Coastal DCC http://www.coastaldcc.co.uk/products/bachrus/

 

I must declare an interest as I have a business relationship (as a supplier) with Coastal.

[Ref44]

Can anyone help with the specification of the screws that hold the wiring tags onto a Dapol Pannier chassis? Disaster struck when the plastic box holding the removed bits fell off the workbench and broke, enabling the carpet monster to swallow the screws.

 

Many thanks  Mike

[RichardBenn]

Can anyone help with the specification of the screws that hold the wiring tags onto a Dapol Pannier chassis? Disaster struck when the plastic box holding the removed bits fell off the workbench and broke, enabling the carpet monster to swallow the screws.

 

I think it might be 11BA. The OD is about 1.15mm and they are about 1.75mm long.

 

HTH

 

Richard

[Ref44]

Richard,

 

Thanks,  it gives me a start point for finding replacements

 

Mike

[nick_bastable]

Richard,

 

Thanks,  it gives me a start point for finding replacements

 

Mike

have you tried DCC supplies ?

 

Nick

[Ref44]

Nick,

 

Have pinged an email to them; am awaiting a response.

[Chris Higgs]

I think it might be 11BA. The OD is about 1.15mm and they are about 1.75mm long.

 

HTH

 

Richard

It will almost certainly be a pure metric size.

 

Chris

[Wyvern]

I am part way through a 4f conversion using the Jinty conversion muffs.   I found when I installed the driving wheels I found that the muffs were extremely tight - a lot more so than the standard 2mm muffs.   I imagine this is because the material is much stiffer than that used for the 2mm standard muffs.   The wheels seemed to have come out ok, but I would be reluctant to install future wheels with such tight a fit for fear of damaging them or the quartering tool.   Do they need opening out slightly to say 1.47mm or so?   Thoughts on a postcard....

[Donw]

I am part way through a 4f conversion using the Jinty conversion muffs.   I found when I installed the driving wheels I found that the muffs were extremely tight - a lot more so than the standard 2mm muffs.   I imagine this is because the material is much stiffer than that used for the 2mm standard muffs.   The wheels seemed to have come out ok, but I would be reluctant to install future wheels with such tight a fit for fear of damaging them or the quartering tool.   Do they need opening out slightly to say 1.47mm or so?   Thoughts on a postcard....

 

I would use a jewellers Broach to ease them slightly. As the Broach is tappered I would work a little from both sides leaving it tight in the middle. Broaches come in sets Eileens Emporium list a 0.6-2mm set something I would recommend in any modellers tookit. Using one is a trial and error job take a little at a time and keep testing.

 

Don

[nick_bastable]

I am part way through a 4f conversion using the Jinty conversion muffs.   I found when I installed the driving wheels I found that the muffs were extremely tight - a lot more so than the standard 2mm muffs.   I imagine this is because the material is much stiffer than that used for the 2mm standard muffs.   The wheels seemed to have come out ok, but I would be reluctant to install future wheels with such tight a fit for fear of damaging them or the quartering tool.   Do they need opening out slightly to say 1.47mm or so?   Thoughts on a postcard....

did you drill a small hole through the centre of the muff?

 

Nick

[Izzy]

I can't say I have found the conversion muffs any different as regards axle fit. I do twist the wheels as I press them into the muff, (I am afraid I have never used a wheel press in any scale), and also dress both the axle end and the muff bore to aid initial egress. It's just a thought, but did you assemble them during the recent spell of hot weather? It might be that the parts expanded very slightly, just enough to make a tighter fit.

 

Izzy

[Wyvern]

I think nick may have hit it on the head - I didn't drill the hole   !   I cant believe I didn't think of that as I have done it for all the previous association muffs I have installed.    

 

Thanks

 

Guy