s scale S Scale 3D Printed Wheels

[Timber]

Hello

 

In this section I will keep you updated on my 3D printed wheels.  The plastic wheels are 3D printed to fit Markit S Scale Axles and Society Tyres.  The price will be approximately £10 per set of four wheels This does not include axles or tyres that will have to be purchsased through the society stores. 

 

The metal wheels are still in development and may not be successful, I will update when I have some news.

 

First up are some 5'2" 16 spoke 12" throw inline drivers, I will add pictures of other wheels as I make them or others ask me to make them for them.  These wheels are an improvement on the ones I shared in the most recent society publication, the profile is slimmer but still supports the Markit nut.

 

 

 

 

Edited January 31, 2021 by Timber

[Timber]

Hello

 

A member contacted me today and enquired about steel wheels so thought that I would provide an update.

 

In the last society publication I shared some pricing for steel wheels.  Unfortunately Shapeways will not print metal components on a spruce so i need to find an alternative.  Individual wheels are too expensive when printed individually. 

 

However, what I can do is to join the wheels so that the rims just touch.  The wheels will have to be seperated with a razor saw.  This may seem odd but I tested on some plastic wheels and found that even with two flat edges the wheels help concentricity in the society tyre....

 

What I have not tested is the end to end design.  Basically each wheel has a a printed axle.  Within the axle and wheel there is a 1.5mm hole.  This will take a 1.5mm glass fibre rod.  There is then plastic collar that sits between the wheel and provides the insulation.  But the proof is in the eating.

 

I can modify the design and just print a 1/8 axle hole.  The printed axle is smooth but not polished.

 

Interested in others thoughts.

 

 

 

 

 

[Rosedale]

This is very impressive and I think that metal 3D printed centres that can be fitted into our tyres and mounted on  a split axle is the holy grail for our scale. So, I take my hat off to you. I would be very interested in the running quality, trueness, concentricity etc. Please keep us posted either here or via email. Brilliant!

[Timber]

Hello,

 

I will photo and update as I produce different wheels.  I have changed the orientation of the prints to a strip as it helps with printing.  

 

Balance weights can be added as required (or not).  Balance weights are smooth no rivet detail.

 

Plastic Wheel Number 1 - to fit 5'2" society tyre- 16 Spoke - 12" throw - PB.

[David Bigcheeseplant]

Have you seen my thread any wheel any size

I use a Gibson tyre, I am now using a harder resin which is giving very good results. Using parametric designs means I can create most wheels by just adjusting  the input table, I keep adding more parameters so can even adjust the spoke profile both in cross section and how it changes along its length.  

[Timber]

Yes - great thread......i think our aproach is very similar.  The power of 3D printing opens up a world of possibilities. 

 

S Scale is a great scale for 3D printing, It is big enough to compensate for minimum printing standards but also not so large that the irregularity of the printed surface cannot easily be smoothed out.  I would encourage anyone who wants to use 3D printing as a means to create models to look seriously at S Scale.

 

Whilst the geometry of wheels is relatively complex, Fusion 360 is an ideal CAD tool for the job.

[Timber]

Plastic Wheel #2

 

5'7" 18 Spoke 10" Throw PB. 

 

With or without balance Weights for Sharp Stewart Cambrian Albion or similar 

 

[flubrush]

How concentric are the wheels when mounted on the Society's Markits Romford-style axles?

 

They are looking good.  If you want to do other diameters,  it's worth a chat with Paul Greene since he might be able to get out tyre supplier to do a batch at another size.

 

Jim.

[Timber]

Hi Jim....good to hear from you.  The wheels appear to be concentric....clearly there are limitations with any two components that screw together but I am running locos on my dodgy track and they are just fine....on my layout I am running my own wheels, Markit and Gibsons but will gradually align on my own wheels with society tyres across my rolling stock....which is only two wagons and seven coaches so not a particularly significant upgrade.

 

I am talking to Paul....this wheel should really be a 5'6" but using a 5'7" tyre is OK.  But I can expand this across any size of tyre.....I did look at Ultrascale but they do not have a front face on their tyres, something that makes aligning the tyre to the wheel that much harder.  Not impossible but losing the inner face of the tyre loses a good reference point.

 

I have developed a plunger pickup to go with the wheel using some readily available components.....I have some parts in the post ..... when they arrive I will share.....

 

 

Edited July 22, 2022 by Timber

[Timber]

Hello

 

I appreciate that most S Scale modellers use split axles, therefore, the subject of pickups is not often discussed.....

 

But I needed a solution for my plastic wheels.  There are some good commercially available items but they have moving parts within the chassis and the wire to the pickup can become an obstacle to smooth operation.

 

I found these pogo plunger pickups that are a good size and not too strong.  Ebay has many of these types of contacts listed, they are typically soldered to printed circuit boards to support mechanical connection to external devices...

 

The beauty of these devices is that the plunger moves within the body, any wire soldered to the body has no imparement on the movement of the plunger, therefore there are no moving parts within the loco frames.

 

The challenge has been to find some that are of the right size and do not act as a brake.....the ones I have landed on have a 2mm diameter body, approx 8mm long and have a 12 gram compression.   Plus they sit nicely inside a Markit 2mm insulated bearing and become a push fit into the frame.

 

I have fitted them to a loco with decent sized wheels and a mashima motor and they run really well.  Clearly any pickup has an element of friction but these work as well as anything else I have tried without constantly fiddling with wires ....

 

Time will tell if these will wear well...

 

[Regularity]

2 hours ago, Timber said:

 

I appreciate that most S Scale modellers use split axles, therefore, the subject of pickups is not often discussed.....

Whilst many do use split axles, I am not certain about “most”, and there is certainly no proscription about not using them.

[flubrush]

That looks like a good solution.    I built one loco with Sharman wheels some years ago and used Gibson plunger pickups and they worked fairly well but getting the wiring right was the problem,  as you note.  I think I used pickup arm wire which was the most flexible I could find.   I was wondering if you were considering inlaying a shorting wire and metal plate in the wheel boss to provide for split axle insulation.

 

Jim. 

[Regularity]

He’s getting some done in metal to my order, Jim.

[Timber]

Here are the brass wheels.....first time I have used brass.....On the CAD i profiled the spokes but this has got a little lost in the printing process.....  Challenge I have is that you have to allow for shrinkage as the metal cools....with steel i worked it out at 0.25%.  With brass it looks a little less.....but there will always be a little trial and error at the start.  

 

 

 

 

[Timber]

I now have 10, 11 and 12 spoke tender wheel centres for our 3'7" society tyre should anyone be interested.

[steveNCB7754]

Hi,

 

Apologies; a) if you have answered this elsewhere and b) for my ignorance, but what is the 'fit' between your wheel centres and the society's tyres?  In other words, what holds them together - press-fit or glue?

 

TIA

 

Steve

[Timber]

I use super glue...I spray paint the wheel and after a couple of hours run a bead of superglue around the rim and then push together....I find that the glue softens the paint and it makes a very strong bond.  Another member who I made some wheels for used Araldite and this worked fine.

 

I have templates now for society tyres, ultrascale tyres, alan gibson tyres and scalelink tyres,  With gibsons and scalelink you have to buy the wheel and push the centres out.

 

Our society tyres are the best as they have a nice front rim that offers additional strength.

 

There is a clip on "what is on your workbench" of a saddle tank running with 3D printed wheels and society tyres,  You will see that it runs nice and smoothly.

 

Any assembly where the axle comes from one supplied, the wheels printed by another fitting to a tyre made by a third supplier all with their own tollerances is never going to be geometrically perfect.  But that applies to anything that is not machined as one piece.  

 

However, I find that our society track standards are actually very forgiving and I am running a mix of all the above tyres through some rather dodgy point work without unexpected derailments.

 

I have just made some Manning Wardle wheels to run with Scalelink tyres I will publish a picture once i have them painted.   I am using Scalelink tyres for these small wheels because while we do have a society tyre that would do the job I use pickups rather than split axles and for these small diameters our society tyres engineered to prototype standards have less metal contact with the pickups.

[Timber]

The society has some nice brass Manning Wardle wheels...here are some with plastic centres should anyone be interested in using pickups rather than split axle

Edited August 11, 2021 by Timber

[Timber]

Just made some 9 spoke 3'7" wheels for a fellow member.  I now have a supply of pinpoint axles should anyone be interested...with the 3D prints, society tyres and newly aquired axles it is possible to make any coach/wagon/tender wheel.

[Rob R]

First go at the 5 ' 7" plain drivers on the Mars.

They don't seem to have shrunk on the OD but the square hole is a little snug and the counterbore for the retaining nut is too small in diameter and I am not convinced that the OD isn't tapered slightly.

I am having another go now but with the print set to 19 deg to the build plate - the same angle that everything else seems to work at for me - to see if I can eliminate some, or hopefully, all of those issues.

Worst case scenario is to place it at a fairly steep angle (say 60 deg or more possibly even 90 deg) but I'm not sure if I will run into concentricity/ovality issues.

I may also tweak the drawing a little and put a small chamfer (say 0.1mm) around the back of the square hole just to help the axle sit true and square.

Time will tell (about 2 hours and counting).

Images taken straight out of the wash and before curing.

Rob

 

 

[apl31]

Very nice Rob.

Something I will want in future for a Furness 2-2-2WT . What are you planning to make with these?

[Rob R]

APL13

 

All being well I have a couple of outside framed 2-4-0's lined up using standard S axles and Markits axle extensions with either Markits cranks or more likely some of my stash of EmSoc/Sharman moulded cranks.

West Midland Railway circa as running 1861, the Hawthorn is ex Oxford, Worcester and Wolverhampton Railway of 1855 and the E B Wilson (with passenger train) is ex Newport, Abergavenny and Hereford Railway about the same date (sorry haven't got the book to hand - RCTS Great Western Locos Vol 3). The Wilson engine of course is slated to use parts from Timbers' Brecon and Merthyr "De Winton"(please!).

The WMR also had a couple of "De Winton" 0-6-0's from E B Wilson (Manning Wardle acquired the patterns etc when Wilson folded) amongst many other very do-able locos.

Photos linked below.

Hawthorn 2-4-0

WMR No.95

All to be found here

Hereford History Images - Building the Hereford and Worcester Railway

I only stumbled upon these photos recently and they are some of the best views of 1850's goods stock I have seen. More work for the printer!

You are more than welcome to as many wheel centres as you need once I have sorted the manufacturing technique. Of course once this wheel is sorted I should be able to do the others as well.

 

Keep safe out there

 

Rob

 

[apl31]

Those are good photos. I wonder how Hellfire Jack keeps his uniform so white.

[Timber]

18 hours ago, Rob R said:

They don't seem to have shrunk on the OD but the square hole is a little snug and the counterbore for the retaining nut is too small in diameter and I am not convinced that the OD isn't tapered slightly.

 

Hi Rob - The hole for the brass nut was sized to be an engineering fit.   To illustrate, as you can see from the pictures below it takes a gentle push for the nut to go into the wheel and the friction is just enough to hold the wheel.  Typically I push the brass nut into the front of the wheel to ease the fit, remove and then fit axle from back and reset the nut onto the axle through the front.

 

If the nut is a good fit, when tightened, this holds the wheel nice and true.   I find that this is better than simply relying on the axle flange and back of wheel.

 

In the New Year I plan to try making some wheels that push onto a 1/8 axle, similar to Gibosons and Ultrascale.   The markit axles are good in that it is easy to take the wheels on and off but I wonder if a push fit will be simpler,

 

 

Edited December 21, 2021 by Timber

[Rob R]

Timber,

Ok, that sounds good.

I still can't push the nut in on my first prints, probably due to shrinkage.

The Shapeways prints of course use a differentmaterial and process so I will have to do a bit of trial and error.

I have some printing now, set vertically on the print bed with the nut recess opened out to 3.3mm on the drawing.

If this is too much then it will be back to the drawing board for a tweak or two.

The push fit method will throw up a different set of issues, whether it is better or worse is just down to personal preference.

In other scales I have had no issues with quartering, assuming the frame and coupling rod centres match and all the wheels have the same crank throw.

I shall keep playing, Paul is sending some tyres so hopefully by the new year I will have some useable wheel sets.

 

Rob