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Discussion Starter · #1 ·
What will follow is how I design, program and print parts prior to assembly. What I intend to do is describe the process and then illustrate it with photos and then a dump of the code used to produce this part. All the code is produced under GNU GPL 2.0. For some reason the editor for this forum collapses the tabs to just /nl. The code will work -it is just not as beautiful...

This is the target locomotive, I t will be produced in "Gauge 3" which is a scale of 1:22.6 running on 63.5mm track or 13.5mm to the foot.


It is not pretty -to be honest the baby warship is dammed ugly. But this is what I have chosen, there are few diesel hydraulics in this period of BR I use the period of 1948 to 1963 as the era of my railway. This enables some economies such as coaches being "Blood and Custard" and diesel locos being BR Diesel Green. Electric locos are BR Electric Blue -which has to be specially mixed, The BR Rail Blue is a totally different colour entirely!!!

And so we begin!

regards
ralph
 

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Ralph,
This will be fun to watch.
A couple of years ago, a friend who was tired of having his Gauge One British trains pulled by a battery powered USA Trains NW2 switcher, asked if I had any suggestions.
I said that maybe I could 3D print a British looking diesel body to fit on the chassis.
Checking the wheelbase of trucks and spacing, I found that the Class 22 would fit.
However, closer examinations showed that the original chassis width was far too wide to look correct, so I ended up making a new chassis too.
The photos show how I only needed to computer draw one cab, and print it twice and then the central body part and the skirts and it was done.
Hopefully your printer will be large enough for the Gauge 3 size that you can do something similar or do you plan on a lot of parts?
Cheers,
David Leech, Delta, Canada
Train Rolling stock Vehicle Railway Rolling


Train Wheel Vehicle Plant Locomotive
 

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Discussion Starter · #4 ·
David,

I operate by making "tiles" and then epoxying them to a plywood backing board. Thus you could say that I make a lot of pieces. The roof will be made from ten sections. The longitudinal part of the body from six pieces at least. The central body has a distinct facet below the driver door window.

Quote a lot of the bodywork has repeatable objects thus coding is going to be fairly straightforward with lots of "yanks & puts" between the source code files.

The chassis frame is going to be made from 13mm x 3mm thick rhs steel. (Its cheap!) The bogie plates made from laser cut 3mm thick BMS and the axles all powered via a single stage 12:90 MOD0.5 spur and bull gear. (I like simple) from a motor, (see elsewhere). Fitted to a 50mm wheel this equates to a std BR 3'9" express loco driver wheel.

The gears I use are made from POCAN which is a ground glass and Nylon composite. Once run in there is no trouble - but fitting gears with a fine glass saw edge to each tooth is often a bloody task!!!

Regards

Ralph
 

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Discussion Starter · #6 ·
Well what I do is (I think) pretty simple. The code is very simplistic and like all of the prior projects aimed at a yr9 with access to his schools reprap and a small source of income!
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this is the side A of the locomotive. It is made from two slabs that I am in the process of cutting holes into to insert the things like doors and radiators. The top slab is inclined by minus 2.5deg in the X axis to produce the facet line on the bodywork. Once this piece is finished I will dump the code here for you to mangle to your hearts content.

regards

ralph
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Discussion Starter · #7 ·
as promised!
//BR class22 SIDEPANELONE.scad

//lower panel
difference()
{
cube([220,60,5]); //side panel to cut out of
{
translate([1,8,-5])
{
cube([3,50,16]); //handrail
}
translate([21,8,-5])
{
cube([3,50,16]); //handrail
}
translate([40,30,-5])
{
cube([30,25,16]); //small radiator
}
translate([120,30,-5])
{
cube([44,25,16]); //large radiator
}
translate([75,5,-5])
{
cube([30,55,16]); //engine door
}
translate([5,5,-5])
{
cube([15,57,16]); //drivers door
}

}//end of holes to cut out
}

//start of things to fill holes
difference()
{
translate([5,5,0])
{
cube([15,(57+30),2]); //drivers door
}
translate([7,(57+3),-5])
{
cube([11,27,16]); //window
}
}
difference()
{
translate([75,5,0])
{
cube([30,(57+30),2]); //engine door
}
{
translate([77,(57+3),-5])
{
cube([11,27,16]); //window L
}
translate([92,(57+3),-5])
{
cube([11,27,16]); //window R
}
translate([89.75,4,1])
{
cube([0.5,(57+29),16]); //door slit
}
}
}


//upper panel


rotate([-2.5,0,0])//facet
{
difference()
{
translate([0,59,4.55])
{
cube([220,40,3]);
}

{
translate([5,58,-5])
{
cube([15,30,16]); //top of drivers door
}
translate([75,58,-5])
{
cube([30,30,16]); //top of engine door
}
translate([40,62,-5])
{
cube([30,25,16]); //small radiator
}
translate([120,64,-5])
{
cube([44,25,16]);
}

}//end of things to cut out}


}
}
//END
 

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Discussion Starter · #8 ·
Well the gcode file from CURA has been fed to the tronxy. According to the sand glasses part one (port) should come off the build plate at 20:35:19. The other side (starboard ) is a simple morror() command.

Doing a 12+hour print is nerve wracking!

But, the part will cost the next builder £0.60p. where possible I like to make a complete model from a single reel of PLA (£10).

Regards
Ralph
 

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Discussion Starter · #10 ·
Yes you are right the A and B ends are not symmetrical. But rather than recode the entire thing I can simply mirror() the required object to this place.

It is 17:52 and the printer os still at work on the first piece! The plans come from the (now extinct) PDH designs in OO scale, so there has been a lot of work with dividers and a slide rule

[X divide 4 multiply 13.5]= Y

But as I said a lot of yank and put between the files
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Regards

Ralph
 

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Discussion Starter · #12 ·
David. If you examine the bottom right hand corner of the drawing - it says page one of two. I do have to admit that shot is a nice one to work from. What is still being printed on the tronxy is the section from the end of 'b' to the end of 'd'.

Section 'e' is a standalone.

But if you examine section 'f' and 'g' this is a mirror() of section 'd and ''c'. The code for this is going to laughably simple, additional radiator vents are removed and a control panel cover plate inserted. I will probably do it whilst waiting for my mug of tea to mash.

Regards

Ralph
 

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Discussion Starter · #13 ·
Here is the screenshot of the third panel of the side of the loco. You will notice that it now sits to the minus side of the X axis as it has been made as a positive and then mirror() used to reflect the code. Its a cheat I know!
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Discussion Starter · #15 ·
And now PAGE2!
These is the fourth and fifth slabs. I have been asked why I don't append the code. This is because the only code you would need is in the first dump. and the other slabs simply consist of moving the cutouts around. The re-enforcing piece at the top helps the angled CUBE statement to hold everything together! Yes, I DO use Debian11...
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