[NorthwestGarrattGuy]

sigh i really shouldn't be trying to do any massive scratchbuilding or 3D printing projects until after things are finished but i got it in my head that i wanted to try 3D printing a CMstP&P EP-2 since its an articulated locomotive and each section should be small enough for the small FDM printer i have but what height should each section be in tinkerCAD

 

[Scott]

Designing it as a series of sub-assemblies works. Also working to the capacity of your printer is the way. Keep a list of the assembly parts and your detail parts.

 

[NorthwestGarrattGuy]

Designing it as a series of sub-assemblies works. Also working to the capacity of your printer is the way. Keep a list of the assembly parts and your detail parts.

well the loco is pretty much 3 section and for trucks the only issue is how i am going to power them also this a kind of an experimental project and things might go anywhere is just kinda of a first attempt

 

[du-bousquetaire]

very interesting project but you will need to make some pantographs and it is quite a job.
Good luck and keep us posted its a fascinating prototype to model.
Simon

 

[NorthwestGarrattGuy]

very interesting project but you will need to make some pantographs and it is quite a job.
Good luck and keep us posted its a fascinating prototype to model.
Simon

well i was planning to just buy LGB pantographs since there close enough

 

[NorthwestGarrattGuy]

here is the current progress on the 3D model

 

[NorthwestGarrattGuy]

actually

Designing it as a series of sub-assemblies works. Also working to the capacity of your printer is the way. Keep a list of the assembly parts and your detail parts.

actually i have a bit of a question which type of filamet should i use? ABS or PLA?

 

[David Leech]

From my experience, if you are only going to run indoors, then PLA is fine.
But NOT if you run outside in the summer heat. Attached photo - PLA in the background.
I could not stand the fumes given off by ABS inside my house, so I use PETG, which a okay in the heat, so far!
Cheers,
David Leech, Delta, Canada

 

[NorthwestGarrattGuy]

From my experience, if you are only going to run indoors, then PLA is fine.
But NOT if you run outside in the summer heat. Attached photo - PLA in the background.
I could not stand the fumes given off by ABS inside my house, so I use PETG, which a okay in the heat, so far!
Cheers,
David Leech, Delta, Canada
View attachment 63788

ok well i was planning to make the frames out of PETG anyway cause its strong and was thinking about ABS for the Shells

 

[Scott]

Yes, good question in regards to powering it. As it's a CO+DO+DO+CO (3+4+4+3) wheel arrangement there are several ways you could do it:
- All wheels powered
- The triple axle bogies as powered and keeping the two 4-axles bogies to spread the weight.
-Triple axles unpowered but work as guiding / trailling bogies spreading the weight and the central 4-axle bogies to power the unit.

It's almost like you're building an electric powered Garratt. Will this be track powered or R/C Battery?

 

[NorthwestGarrattGuy]

Yes, good question in regards to powering it. As it's a CO+DO+DO+CO (3+4+4+3) wheel arrangement there are several ways you could do it:

• All wheels powered
• The triple axle bogies as powered and keeping the two 4-axles bogies to spread the weight.

-Triple axles unpowered but work as guiding / trailling bogies spreading the weight and the central 4-axle bogies to power the unit.

It's almost like you're building an electric powered Garratt. Will this be track powered or R/C Battery?

battery also what i am thinking so far is to have a C-4+4-C arrangment also the prototype is actually a 1B-D+D-B1

 

[Scott]

So both of the three axle bogies had two wheels powered and a idler axle? Intriguing indeed.

 

[NorthwestGarrattGuy]

So both of the three axle bogies had two wheels powered and a idler axle? Intriguing indeed.

Yep

 

[Scott]

Wouldn't that be more of a A-1-A setup? Much like some of the Alco Locomotives.

 

[NorthwestGarrattGuy]

Wouldn't that be more of a A-1-A setup? Much like some of the Alco Locomotives.

nope because its 1B-D+D-B1 its a B truck with an idler axle on the front rather than the middle

 

[Exador]

Quite a while back I purchased an extender kit for increasing my vertical print to 400mm from 250mm. Was about $40 and we'll worth it if you can stand 120 hour prints!

 

[NorthwestGarrattGuy]

Quite a while back I purchased an extender kit for increasing my vertical print to 400mm from 250mm. Was about $40 and we'll worth it if you can stand 120 hour prints!

Could be mildly helpful if it works for the voxelab Aquila printer

 

[ralphbrades]

Interesting! I have been printing locomotives for a couple of years now, but nothing as big as this... I use the open source design language called Open.SCAD. My working scale is Gauge '3'.

I work by printing 5mm thick "tiles" in PLA and bonding them to plywood frames. I normally power all axles via simple printed OU shaped fitting with the motor clamped in in the O and the axle shaft dropped into the U with a retaining piece slipped into the U cavity..

The motor/axle is 5W and is fed from a 12V 7.5 Ah SLA to a 15A ESC (with a coolant fan!!!) To the buss bar.

The chassis frames are simple 3mm steel plates to which the external "gubbins" are printed and stuck to. Because of curve radius I normally produce B0-B0 and C0-C0 bogied locos. I have produced a 2-D0-2 loco but the sideplay required is just dire!

Good luck with your project and I will follow your progress with interest.

Regards

Ralph

 

[ralphbrades]

Sorry -this should help! Just cut and paste the source code into CURA (with the open,SCAD plugin)
-------------------------------------------------------------------------------------------------

//axle securing block
//smemotormount

difference()
{
cube([33,20,7]);
{
translate([0,0,3.5])
{
rotate([0,90,0])
{
cylinder(40,3.5,3.5);
}
}
}
}
//END

----------------------------------------------------------------------------------------------------------------
And the OU part
----------------------------------------------------------------------------------------------------------------

//wonder engine SME motor mount
//12Tmod0.5 on motor
//90Tmod0.5 on wheel

//faceplate
difference()
{
cylinder(3,17,17);
{
cylinder(4,5,5);
translate([7,0,0])
{
cylinder(4,2,2);
}
translate([-7,0,0])
{
cylinder(4,2,2);
}
translate([0,7,0])
{
cylinder(4,1.5,1.5);
}
translate([0,-7,0])
{
cylinder(4,1.5,1.5);
}
}
}

//holding tube
translate([0,0,3])
{
difference()
{
cylinder(30,17,17);
translate([0,0,3])
{
cylinder(34,14,14);
}
}
}

//axle U
difference()
{
translate([25.5,0,0])
{
cylinder(33,11,11);
}
{
translate([25.5,0,-2])
{
cylinder(40,3.5,3.5);
}
translate([22,0,-2])
{
cube([7,20,40]);
}
}
}

translate([29,0,0])
{
cube([5,15,33]);
}
translate([17,0,0])
{
cube([5,15,33]);
}

//damper fitting
difference()
{
translate([13,5,0])
{
cube([9,23,10]);
}
translate([18,22,-5])
{
cylinder(20,1.5,1.5);
}
}
//END
-----------------------------------------------------------------------------------------------------
The motor I use is 25mm dia and has a 2.3mm shaft. By altering the raw dimensions you can adapt this to fit any motor. The axle shaft can be either 6mm (a common hear bore) or 6.4mm (Slaters wheels). The 90TMOD0.5 gear is a perfect fit for a BR 3 feet 9 inches diesel wheel at 1:22.6.

regards

ralph