21E tram truck

[Melbournesparks]

Finally got around to testing and uploading a complete 3D printable tram truck. Using the same tram traction motors developed previously, you can use this truck to re power Bachmann trams, or for your own scratch building projects.



Brill 21E trucks like this were extremely common on early 4 wheel trams all over the world. This one is modelled to approximately 1:24 scale, though they came in various sizes and lengths.




It is designed to be fitted to a Bachmann tram using the existing screw holes, though note some cutting and trimming of the plastic mounting posts will be required.

You can download the files from thingiverse:

Thingiverse - The community for Open Hardware

Thingiverse - The community for Open Hardware

www.thingiverse.com

 

[DafyddElvy]

Your design has appeared just at the right time, how did you guess.

3 Tweaks, to suit my own modelling, I'll be asking man CAD friend to make so the whole truck can be printed as a single unit and also because my trams are sprung.

• The whole truck will be printed as a single piece, this will allow me to have the life tray cross member printed as part of the truck, and have a corresponding truck side support/brace at the top of the frame.
• The axle boxes will be removable so I can have them sprung, I already have a selection of springs and do this with the white metal truck sides I use.
• The central cross member will be printed as part of the truck and used to secure the truck to the tram body where Bachmann fix the weights, this is the fixing arrangement I started using when I converted a tram to a trailer.

I'm not suggesting these are improvements but personal preference tweaks, I really can not tell you how much of a happy modeller you have made me by drawing up these items, and how grateful I am, and for doing it as I have entered this larger scale, you couldn't have timed it better, thanks.

So what next?

 

[DafyddElvy]

Mr. Sparks, I don't know if the significance of what your hard work in designing traction motor and now drawing the truck sides means to the hobby, at least in the circles I roam.

My conversion of a Bachmann trams has cost circa £130 for each model just for traction motors, you have now reduced this to under £40 including slaters wheels, this makes tramway modelling in our scale a lot more attractive and less unattractive financially and I for one believe thanks are due for the work you've done and for making the CAD files freely available to us, so thank you.

 

[Ralphmp]

Mr. Sparks, I don't know if the significance of what your hard work in designing traction motor and now drawing the truck sides means to the hobby, at least in the circles I roam.

My conversion of a Bachmann trams has cost circa £130 for each model just for traction motors, you have now reduced this to under £40 including slaters wheels, this makes tramway modelling in our scale a lot more attractive and less unattractive financially and I for one believe thanks are due for the work you've done and for making the CAD files freely available to us, so thank you.

Does the £40 include capital outlay on a suitable printer, printing materials and electricity costs? If so, it does appear to be a very economical way to create your own models.

 

[Melbournesparks]

Your design has appeared just at the right time, how did you guess.

3 Tweaks, to suit my own modelling, I'll be asking man CAD friend to make so the whole truck can be printed as a single unit and also because my trams are sprung.

• The whole truck will be printed as a single piece, this will allow me to have the life tray cross member printed as part of the truck, and have a corresponding truck side support/brace at the top of the frame.
• The axle boxes will be removable so I can have them sprung, I already have a selection of springs and do this with the white metal truck sides I use.
• The central cross member will be printed as part of the truck and used to secure the truck to the tram body where Bachmann fix the weights, this is the fixing arrangement I started using when I converted a tram to a trailer.

I'm not suggesting these are improvements but personal preference tweaks, I really can not tell you how much of a happy modeller you have made me by drawing up these items, and how grateful I am, and for doing it as I have entered this larger scale, you couldn't have timed it better, thanks.

So what next?

Glad it will be useful! I expect many people will need to make modifications to suit their particular purposes and application. Because I'm printing in PLA using a FDM printer I had to orient the parts for printing in a way that aligned the strongest axis of the materials with the load paths. I noticed you've been printing in resin which should give a lot more design freedom, as well as much better detail resolution. I'm sure the sprung axle boxes will give a very good ride quality.

Mr. Sparks, I don't know if the significance of what your hard work in designing traction motor and now drawing the truck sides means to the hobby, at least in the circles I roam.

My conversion of a Bachmann trams has cost circa £130 for each model just for traction motors, you have now reduced this to under £40 including slaters wheels, this makes tramway modelling in our scale a lot more attractive and less unattractive financially and I for one believe thanks are due for the work you've done and for making the CAD files freely available to us, so thank you.

That was hopefully the goal, the high cost of everything has been a huge barrier to entry for people coming into large scale tramway modelling. I have been using either Bachmann or Grootspoor wheels which are even cheaper than Slaters.

Does the £40 include capital outlay on a suitable printer, printing materials and electricity costs? If so, it does appear to be a very economical way to create your own models.

A complete 21E truck and traction motor cases consumes about $4.20 Australian dollars worth of filament at current prices. This is definitely on the low end of new material costs for an object this size, though of course using traditional scratch building techniques you can often obtain recycled materials for free. Electricity costs would be so little that it would be difficult to measure here. 3D printers themselves are still in the hundreds of dollars, though all investment in tooling costs money and there are libraries and commercial printing services as alternatives to investing in your own machines.

 

[DafyddElvy]

Sounds silly to me now, but I hadn't spent much time looking at alternative wheels, smack on the hand for that mistake, must look harder, thanks.

 

[DafyddElvy]

Does the £40 include capital outlay on a suitable printer, printing materials and electricity costs? If so, it does appear to be a very economical way to create your own models.

For the traction motor the biggest cost for me is wheels.
10 motors shipped circa £10, 100 of each of the gear types circa £32.
I made an estimate for the resin printing, however you work it out it's still about 1/3 of the cost of a commercially available product, it works, its reliable and very simple to assemble, making the ideal option in my mind.

 

[Melbournesparks]

Sounds silly to me now, but I hadn't spent much time looking at alternative wheels, smack on the hand for that mistake, must look harder, thanks.

The Bachmann wheels are very cheap, though the metal they are made from is less ideal for electrical pickup in an outside environment. The Grootspoor wheels that I used in the example pictured in this thread are good, with spokes and stainless steel running surfaces. Their main disadvantage is that they have deep LGB type flanges, so may not be compatible with fine scale tramway track. I also use the brass axle bearing for electrical pickup, so need to ground the wheels to the axle. For the Grootspoor wheels this is done by pressing the wheel off the axle, then the stainless steel wheel rim off the plastic wheel centre. A bit of thin stainless steel wire is then threaded around both and the wheel pressed back together. A bit of a pain, but I haven't really found a better way to do it.



One more picture showing the 21E truck fitted to a bachmann tram. This tram is part way through conversion to a Sydney C class, so has had some modifications to the end platforms.

 

[PhilP]

I am sure there was a thread, with all the details of your trucks (powered bogies)?
I now can't find it, and am wondering if these could be adapted to my needs for GP38 - 2 power-bogies?

I know there will be some design work involved, but the cost of the (not very robust) OEM components, plus shipping etc. makes this worth investigation.

PhilP

 

[Melbournesparks]

I am sure there was a thread, with all the details of your trucks (powered bogies)?
I now can't find it, and am wondering if these could be adapted to my needs for GP38 - 2 power-bogies?

I know there will be some design work involved, but the cost of the (not very robust) OEM components, plus shipping etc. makes this worth investigation.

PhilP

It was possibly this thread, about the traction motor case that this 21E truck uses. These traction motors are relatively light duty so I'm not sure how effective they'd be in a heavy rail locomotive application. The good news however is that a project is currently in progress to develop a traction motor suitable for heavy duty locomotive applications, watch this space.

 

[tramwayknowledge]

I have been following the development of this project with growing enthusiasm. You have certainly created an elegant 1'24 truck, something that many of us have been wanting for a long time.
It certainly takes the Bachmann car from being a 'toy that can be made to look something like the prototype' to a 'decent model of a first generation car. Given the number of car bodies that I have in the 'Pending' box I estimate that I could use 4-6 of these per year for a couple of years.

The trouble is that when you get to my age the workbench is cluttered with tools and gizmos and the old brain is resistant to buying new tools and learning a new skill from the ground up. Now. if someone with the right tools could make up assemble-it-at-home kits of parts at a reasonable price I would be at the front of the queue. I might even be able to give a hand with the making up of the packets of parts and their marketing...

.IS THERE ANYONE WHO WOULD TAKE UP THE CHALLENGE OF PRINTING THE BITS AND SOURCING THE WHEELS AND MOTORS?

 

[DafyddElvy]

I have been following the development of this project with growing enthusiasm. You have certainly created an elegant 1'24 truck, something that many of us have been wanting for a long time.
It certainly takes the Bachmann car from being a 'toy that can be made to look something like the prototype' to a 'decent model of a first generation car. Given the number of car bodies that I have in the 'Pending' box I estimate that I could use 4-6 of these per year for a couple of years.

The trouble is that when you get to my age the workbench is cluttered with tools and gizmos and the old brain is resistant to buying new tools and learning a new skill from the ground up. Now. if someone with the right tools could make up assemble-it-at-home kits of parts at a reasonable price I would be at the front of the queue. I might even be able to give a hand with the making up of the packets of parts and their marketing...

.IS THERE ANYONE WHO WOULD TAKE UP THE CHALLENGE OF PRINTING THE BITS AND SOURCING THE WHEELS AND MOTORS?

Some modelling friends have already asked me to do exactly that for our wee group, not on a commercial basis but for those of us that locally model in the larger scale.

You wouldn't be at the front of the que but if you're in britain I wouldn't mind sending you a set of parts.

 

[PhilP]

Some modelling friends have already asked me to do exactly that for our wee group, not on a commercial basis but for those of us that locally model in the larger scale.

You wouldn't be at the front of the que but if you're in britain I wouldn't mind sending you a set of parts.

His profile suggests Fife, so not a million miles away from you.

 

[Melbournesparks]

Certainly much closer than me! I did initially think about trying to produce some kits or complete units for sale, but the economics really don't stack up. By the time I source all the parts and pay to have them shipped half way around the world, put the machine time into printing, my own time into assembling, procure packaging materials and eventually ship the completed product back to the other side of the world it goes from a very budget solution to a pretty expensive one real quick. Not to mention any time I devote to it would be time taken away from modelling, so I'd want to pay myself a reasonable hourly rate. For people who's save money <---> save time and effort equation skews more towards the latter there are a number of already existing commercial products that you can buy ready made that do basically the same thing. This was really intended to fill a void at the other end of the market where up until now there's been very few options.

I realise the long shopping list of required parts is a bit of a pain, though everything seems to be easily findable through an ebay search at the moment. If some of the particular parts required become hard to find the design might have to be adapted.

Some modelling friends have already asked me to do exactly that for our wee group, not on a commercial basis but for those of us that locally model in the larger scale.

You wouldn't be at the front of the que but if you're in britain I wouldn't mind sending you a set of parts.

So given the time involved it is very kind of you to offer to assemble some for others! As long as people aren't actually selling parts made from these designs in a shop for profit I'm happy for anyone to use them in any way that helps them get their large scale trams running. I don't think it would be a problem anyway since like I said you'd have to sell them for absurdly high prices to make any profit. Would love to see any pictures of completed units in service!

 

[tramwayknowledge]

Some modelling friends have already asked me to do exactly that for our wee group, not on a commercial basis but for those of us that locally model in the larger scale.

You wouldn't be at the front of the que but if you're in britain I wouldn't mind sending you a set of parts.

Im in Falkland Fife...so I guess I'm no far from you.......and I don't really hope that this will be a way to add a significant sum to my pensions!

 

[DafyddElvy]

Im in Falkland Fife...so I guess I'm no far from you.......and I don't really hope that this will be a way to add a significant sum to my pensions!

Are you a member of the TLRS?
Do you have a layout or garden line?
Would you like to share some photos of your models.

I live 1.9km from Breich station.

I'll ask the pal in Falkirk to add a few more traction motor prints to his to do list and I'll add a few motors to my next order when I get back from Porto, where my wife says every tram driver must know me by now.

 

[borsig1963]

great job, but I have a problem: the zip file doenloaded from thingiverse is empty...

thanks, Paolo

 

[Melbournesparks]

great job, but I have a problem: the zip file doenloaded from thingiverse is empty...

thanks, Paolo

Looks like thingiverse is being unreliable. Try clicking on each file individually, there's only 3 of them.

 

[borsig1963]

Looks like thingiverse is being unreliable. Try clicking on each file individually, there's only 3 of them.

ah perfect, now is ok, thanks a lot - grazie !

Paolo

 

[3 minutes of fame]

These print very nicely. I designed something similar a while back for a tram project I am working on, and the overall length is spot on. I've modelled a shorter wheelbase version with the revised axle boxes, comparison below.


This is the print just push fitted into my tram body. A perfect fit!