Dave's 4mm scale loco scratchbuilds. (Manning Wardle 1802)

[Herb Garden]

It has advanced a little.

The frames now have 3-point compensation, are painted, motor, wheels and cylinders fitted.
View attachment 218527
I have made the connecting rods and have put power to the motor with them fitted - all good.

Bodywork.
View attachment 218528

Dave,

Following this one with a lot of interest.

You are making me question why I always use thin gauge material for my scratch build projects. (Maybe I'm just too used to etch kits). Seeing your use of heavy gauge materials in both the chassis and parts of the body makes me think why don't I use these thicknesses myself? Why don't I look at machining things from solid more? All possitve reflections and ones I will have to look at more in my next projects.

I've never heard of N20 gearbox's what are they like and where does one get them from?

 

[Dave]

I've never heard of N20 gearbox's what are they like and where does one get them from?

Hi George. As far as I know, N20 refers to the motor size but if you search ebay for "N20 gear motor" you will find these motors with gearboxes attached. I think that they are intended for door locks and such like. They are advertised as having various output R.P.M. (at what voltage I cannot say) so avoid the really low figures. I have used 200 or 300 R.P.M.

They may only be small motors but when coupled with the gearboxes they are very powerful. I got the idea of using them from reading an article by Geoff Helliwell in the April 2018 Railway Modeller. He made a motor bogie powered by one and was able to press down on it as hard as he could but was unable to stall it.

 

[Herb Garden]

Hi George. As far as I know, N20 refers to the motor size but if you search ebay for "N20 gear motor" you will find these motors with gearboxes attached. I think that they are intended for door locks and such like. They are advertised as having various output R.P.M. (at what voltage I cannot say) so avoid the really low figures. I have used 200 or 300 R.P.M.

They may only be small motors but when coupled with the gearboxes they are very powerful. I got the idea of using them from reading an article by Geoff Helliwell in the April 2018 Railway Modeller. He made a motor bogie powered by one and was able to press down on it as hard as he could but was unable to stall it.

Now you come to mention it I vaguely remember that article.... Should really look it up.

It's interesting to hear your thoughts on the power of these units. I've been using high level units to power my locos recently which are great but they do take up space. The Sharpie single has a big old 12/20 coreless in the tender which packs a punch but by the time you account for the losses through the two gearboxes and layshaft between it might have been better to have a smaller power pack in the loco these might fit the bill....

 

[Dave]

Instead of making the tank with slab sides to fit the space between cab and smokebox, which depends on me accurately measuring and making it to fit, I'm building it using a skeleton. The rods fit into holes in the cab and the leading rib has a hole that fits a rod through the smokebox. With the cab and smokebox ribs butted squarely against those parts I can solder the ribs to the rods. It should all fit precisely. Until I have added the wrapper and then it'll probably all go wrong.

 

[simond]

@Giles has used them for years in his R/C vehicles, both road and rail.