Tram Engine

This is a Tram Engine based on the Bobber Caboose, but now with the "planks" horizontal like photos of LNER J70 (/ GER Class C53). A video of the prototype being tested is here: https://youtu.be/43rY8J1DrOc

You can add the "Toby Face" , modified from http://www.thingiverse.com/thing:293591, and a driver, http://www.thingiverse.com/thing:1413975 (here he is enlarged in x and y, to make him a "fat driver!)

Four of the wheels are powered, by "TT Motor" gearboxes from EBAY, search for "TT motor Ardunio". They are about £2 each or so. The wheels are to G1MRA guidelines for "standard" wheels on 45mm track. There are also "treaded" wheel versions, that take two 20mm*1mm square cross section rubber bands to improve traction.
(In the photos I did not spot I had fitted three treaded wheels and three standard wheels).

UPDATE March 30 2016 : following tests, I would advise changing to the "28mm" diameter wheel to give a bit more clearance, especially on bumpy track and points. I have put the "28mm g1mra" wheel stl in the files. With the rubber tyres, the tram can push about 8 oz, but even with the normal wheels it can still push more than 5 oz, so I would recommend using the normal wheels and not use the rubber tyres unless you have very steep track or lots of carriages to shift. You do not really need the centre, un-driven wheels.

If you want to fit "LGB" couplings, or my servo driven one http://www.thingiverse.com/thing:1000218 , then you will need to cut out a section of the cowcatcher. There is a photo that shows this. I also found on the test run that the cowcatcher did catch on some bumpy track, so there is a second version "Higher CowCatcher" that has a little more clearance, but I would recommend trying changing the wheels to the 28mm versions first.

There is also a "slightly smaller steps" stl that makes "slightly smaller" steps that may be easier to fit in the base!

I had a lot of problems with the side panels "shearing". I think a heated enclosure around the printer is needed to get these to print well.

The base takes 6 AA batteries. The springs and connections came from cheap (ebay) "2AA battery boxes".
In the Video the tram is running from a 2S 2000mAh Lithium cell mounted loosely in the cabin. I do not think that AA batteries would be able to drive the 55mm EDF unit, and the EDF controller can get confused if not fed by a Lithium cell.

The motors work well from 3V, so only 2 AA batteries are needed as a minimum to run the Tram nicely, and you can fit these in the boiler if you want. I have found a DC speed controller on Ebay that works well, and the boiler has fittings to take this. But its better to use the 6 AA batteries in the special holder in the base.
The motors, buffers cow catcher etc are held in place by 3mm filament sections.
The lamps are held by 1.75mm filament sections or bits cut from by cocktail sticks .
Screws are "# 4" size, 6.6mm or 13mm. DRILL all the clearance holes to 3mm, and the parts that they screw into out to 2mm before trying to fit the screws!!!
Hopefully the pictures should explain everything else.