3D Printed Lima Gear Replacement

Thanks Echidna,
My intention has always been to just run the rail cars individually or as they are, certainly in the case of the express parcels.
The passenger rail car could have a coach or a couple of vans as you say, just to create a bit more interest.
The running trials I`m conducting at the moment are designed to stress the new replacement gear, and indeed try and break it, because we are in unknown territory here.
Can a 3D print of this small size stand up to the everyday punishment required of it in the rail car gear train...???...who knows...???....but for my own peace of mind and probably Chris`s as well....I need to know.
The results will help anyone going down this route in the future hopefully
So at the moment....the big question....and probably the only question is .....will it last ?....because we now know that it certainly works.
Happy days Echidna, when we can source new parts from 3D printers and keep the trains running.....
Gormo

 

Thanks Mossy.......Merry Christmas to you lot up North too.
We won`t get snow here but so far we`re having a cooler than normal lead up to the festive season.....things are a changin`
Gormo

 

Further running on the rail car today, approx. 30 minutes with a train in tow and a further 40 mins running the length of the branch and back under the control of the auto shuttle.
Still no issues........
Gormo

 

Thanks Andy,
I think you`re talking about my train detection system track diagrams.
That is explained in the video below from 15 mins 22 secs starting point.
I have since changed the method of detection, however the panels still work in the same way


Gormo

 

Well folks,
It`s time to evaluate the 3D printed gear.
I`ve removed it from the loco today after it`s had considerable running, enough running indeed to break it if that was going to happen, and in fact it is not going to happen because the integrity of thing overall is good.
I think however, the one thing to be considered is the product used for lubrication.
What you will see in the video below is some pitting on the surface of the gear which I think must be due to some incompatibility with Inox.
Inox is supposedly safe on most plastics, but I think long term on resin it may slowly eat it away.
Therefore, the search is on for a non corrosive, non toxic method of lubrication.......my first thoughts being a vegetable oil or some such thing which you would think would be safe enough to use.
More research required on that one.
Anyhow......I think the 3D printed gears are up to the job long term, but we don`t know these things until we try them, so I am always open to trying things, because eventually most problems can be solved.
This image below shows what appears to be a surface that is eroding and that must be down to the lubricant.





A video through the microscope



Gormo

 

G`day Chris,
Yes I`m not particularly worried at this stage about the pitting, however what is unknown is it`s effects long term. The Inox may be working away like a cancer that will slowly destroy the part.
I have wiped the part and surrounding gears clean for the moment which might slow the process ......so we wait and see.
In the meantime....I`m open to ideas like your Graphite suggestion.
I think some people use it on their track to improve electrical conductivity ??....but I think I remember reading that process plays havoc with traction tyres.....not sure....can`t remember....
Anyhow I will try your suggestion when we emerge from the Christmas excess and dull hangovers......Oh just remembered..... gotta get through New Years yet......
I will research again on the internet and there is bound to be a simple solution that has been flying under the radar all this time.
Ain`t technology great....
Gormo

 

Gormo

 

I guess one solution for lubrication could be KY Jelly........a tip that was passed on to me years ago.
Safe to use on human skin and I think it`s water based..???
Just looked it up.......contents are .....Water, Propylene Glycol, Hydroxyethylcellulose, Benzoic Acid, Carbomer, Sodium Hydroxide.......Hmmmm...?????
Gormo