RC Locomotive 'Diesel-Electric'

[WickedFog]

I then went on to the job i was dreading the axles, made from ground silver steel rods, machining these seems to eat my tooling. I wish I could figure out a better way to make the reduced dia ends as the distance between the internal shoulders is quite sensitive as it sets the distance between the wheels.
I am currently machining the axle to its final length then cutting the reduced sections the correct length to set the shoulders the right distance apart. Any way heres a picture of two axles in a box of increasing pile of parts

View attachment 270684

We had our lathes setup with a stop we could setup for these types of jobs. This is a cutaway of the spindle, chuck would be mounted on the right end. Basically just a bar inside the spindle to be a stop for your workpiece.

 

[Roog]

We had our lathes setup with a stop we could setup for these types of jobs. This is a cutaway of the spindle, chuck would be mounted on the right end. Basically just a bar inside the spindle to be a stop for your workpiece.
View attachment 270688View attachment 270689View attachment 270690

Ah of course, now you mention this I’ve seen YouTube machinists extolling the virtues of stops when making multiple items the same

 

[Roog]

today the temperature in my shed will be mostly,

Or 56F topped put at 15.5C its getting warmer! At least my visor eye protection didn’t mist up today.

Fed up with making axles i moved on to tapping threads and making spacers to set the wheels centred on the bogie

Parting off the first one, wow, I’d forgotten how nice brass is to machine.

And heres a set of four

The DRO I have fitted to the lathe has a more modern display, it is quite a bit clearer to read than the old LED one I have on the mill.

Now back on to making axles, new tip makes light work of the first few cuts.

Wheel seated on axle and

The last one set up with the wheel spacer and bearing stacked in position.

Didn’t quite go to plan though, on the very last shaft end, i released the power feed and I didn’t do it quite as decisively as i should and by the time i managed to hit the ‘E-stop’ the tooling had pushed 1.5mm past the required shoulder position, a critical dimension on the axle. Not in the mood to make another i made a steel spacer, you can’t see it in the image above because it’s hidden behind the wheel!

One partly completed bogie and parts to make the second, getting there….slowly.

And yes the bench is very messy.

Next up is the pivot ‘pin’ and platform on which the chassis sits. Hey it’ll make sense when you see it.

 

[WRM]

today the temperature in my shed will be mostly,

View attachment 270725

Or 56F topped put at 15.5C its getting warmer! At least my visor eye protection didn’t mist up today.

Fed up with making axles i moved on to tapping threads and making spacers to set the wheels centred on the bogie

View attachment 270726

Parting off the first one, wow, I’d forgotten how nice brass is to machine.

View attachment 270727

And heres a set of four

View attachment 270728

The DRO I have fitted to the lathe has a more modern display, it is quite a bit clearer to read than the old LED one I have on the mill.

View attachment 270729

Now back on to making axles, new tip makes light work of the first few cuts.

View attachment 270730

View attachment 270731

Wheel seated on axle and

View attachment 270732

The last one set up with the wheel spacer and bearing stacked in position.

Didn’t quite go to plan though, on the very last shaft end, i released the power feed and I didn’t do it quite as decisively as i should and by the time i managed to hit the ‘E-stop’ the tooling had pushed 1.5mm past the required shoulder position, a critical dimension on the axle. Not in the mood to make another i made a steel spacer, you can’t see it in the image above because it’s hidden behind the wheel!

Next up is the pivot ‘pin’ and platform on which the chassis sits. Hey it’ll make sense when you see it.

It's not about being perfect, it's about how you fix the occasional "Oops". Well done!

 

[Roog]

It's not about being perfect, it's about how you fix the occasional "Oops". Well done!

Aww shucks, thanks @WRM, can we forget that I swore blue murder for five minutes solid after messing up!

 

[WickedFog]

Looks awesome man. I wish I was your neighbor. I'd be over turning handles with ya.

Will these bogies (trucks over here) have suspension?

 

[Roog]

Looks awesome man. I wish I was your neighbor. I'd be over turning handles with ya.

Will these bogies (trucks over here) have suspension?

Ha…I suspect you would be shouting at me constantly “doing it wrong, again!”

I did ask about suspension, big models definitely, in smaller models less so, one of the reasons why I went for two axle bogies rather than three. Of course I may regret this!

 

[CertifiedMike]

today the temperature in my shed will be mostly,

View attachment 270725

Or 56F topped put at 15.5C its getting warmer! At least my visor eye protection didn’t mist up today.

Fed up with making axles i moved on to tapping threads and making spacers to set the wheels centred on the bogie

View attachment 270726

Parting off the first one, wow, I’d forgotten how nice brass is to machine.

View attachment 270727

And heres a set of four

View attachment 270728

The DRO I have fitted to the lathe has a more modern display, it is quite a bit clearer to read than the old LED one I have on the mill.

View attachment 270729

Now back on to making axles, new tip makes light work of the first few cuts.

View attachment 270730

View attachment 270731

Wheel seated on axle and

View attachment 270732

The last one set up with the wheel spacer and bearing stacked in position.

Didn’t quite go to plan though, on the very last shaft end, i released the power feed and I didn’t do it quite as decisively as i should and by the time i managed to hit the ‘E-stop’ the tooling had pushed 1.5mm past the required shoulder position, a critical dimension on the axle. Not in the mood to make another i made a steel spacer, you can’t see it in the image above because it’s hidden behind the wheel!

One partly completed bogie and parts to make the second, getting there….slowly.

View attachment 270734

And yes the bench is very messy.

Next up is the pivot ‘pin’ and platform on which the chassis sits. Hey it’ll make sense when you see it.

Your weather was slightly warmer than mine today. We will be complaining of too much heat and humidity soon enough!

It already looks 'right'. I could picture a few of these lying around in a train yard waiting for install.

Next level build right here!!!

 

[Roog]

Your weather was slightly warmer than mine today. We will be complaining of too much heat and humidity soon enough!

It already looks 'right'. I could picture a few of these lying around in a train yard waiting for install.

Next level build right here!!!

For reasons I can’t explain most of my builds happen in the winter, thankfully my shed is hidden behind big hedges and under a 65 year old cedar tree so it keeps a sensible temp in the summer.

Thinking more about suspension, I was led by the configuration of the commercially produced locos available as kits or ready made in the UK, even those of 5” gauge, tend to use very simple folded sheet steel trucks with plain bearings similarly the chassis are large folded sheet metal. As I don’t have the means to bend big sheet metal my chassis will be fabricated from angle with ‘rungs’ like an old car chassis, I just hope it works OK.

I did ask whether i could use aluminium for my build and it was recommended that i use steel for its weight, this was further amplified by the bloke who sold me the piece of track who seemed surprised that i was building a ‘small one’ and added “better make it heavy then”!

 

[Roog]

I’ll try to post a meaningful line drawing if i can get around to it.

 

[Roog]

Missus Roog is rushing about re some Easter event, so I booted the PC for some pictures.

Engine is a bit of a squeeze, OS MAX 120 AX is my engine of choice, max revs at 9500rpm at 3.0 PS (hp) is relaxed by IC standards, hoping to run it a bit slower if possible. Muffler is going to be tight too, again hoping to silence it as much as possible. Ultimate power isnt my aim here, 1 hp should be enough.

25 V LIFe PO4 battery is going to sit in an aluminum box slung below the chassis rails. Low capacity battery charged by IC driven generator, if it works.

Current thinking on motors is 6378 FLipsky skateboard motors, I guess these should be quite tough!

That’s frustrating, the pdf images are ‘pin sharp’ they go a bit fuzzy when you convert to jpg. I’ve not dimensioned them because I keep changing them and I’m lazy, i measure directly from the CAD model on screen using the measurement widget and draft a hand drawing for each part. Engine cooling is going to be interesting, current thoughts are to suspend a fast centrifugal fan drawing from a grille in the roof and blowing directly over the cylinder.

 

[CertifiedMike]

The lines look good here, the drawings are impressive!
The fan for cooling is a great idea!
Is it possible to direct cool air across the head fins directly?
I think that will give the best cooling if that is an option.

Def would want to be running that motor at less than WOT for heat and noise issues.

Good luck searching for eggs later today!
Happy Easter!!!

 

[Roog]

Most locos have big vents either side of the bodyand sbove, so hopefully i can get a fan in there somewhere, just got to keep heat away from the alternator and escs/rc gear

 

[Roog]

Pivot pins, spacer and platforms for each truck today.

Turning down the 12mm diameter from 3/4” stock bar.

Formed a robust shoulder and locating protrusion to fit the truck top plate

Now onto the spacer, this is currently over sized and may need to be adjusted down in size later

Next drilling clearance holes

Once done i remembered that i needed to create a recess in the bottom of the spacer for the pin shoulder with a boring bar, i have no idea why i left so much hanging out the end

Satisfying snug fit between these parts despite just being a spacer, the top plate was hand cut from 3mm thick mild steel and finished by hand filling, which is why it looks a bit rough, perhaps i should invest in rotary table for my mill!

Finished item loose assembled

The plan is to place both trucks on the track in a siding, them lower the chassis over them in turn. Whilst I expect gravity to hold everything together, I was planning on using ‘R’ pins to retain the trucks, but maybe a compression collar might be better?

Again ideas welcomed. :0)

 

[Roog]

Heres a question, i want to fit two ‘buttons’ of slippery material to the underside of the chassis cross members which will rest on the table/platform above.

Do you know of any thing like this? I notice that my telescope sits on similar waxy pads which lube movement but have just the right amount of resistance to stop it spinning perhaps ill check telescope supplies

 

[CertifiedMike]

Delrin is a self lubricating plastic. Would that work?

 

[Roog]

Delrin is a self lubricating plastic. Would that work?

Thanks @CertifiedMike i have heard of Delrin, I’ll check it out.

 

[Doom!]

@Roog I love watching your work!

 

[WickedFog]

Missus Roog is rushing about re some Easter event, so I booted the PC for some pictures.

Engine is a bit of a squeeze, OS MAX 120 AX is my engine of choice, max revs at 9500rpm at 3.0 PS (hp) is relaxed by IC standards, hoping to run it a bit slower if possible. Muffler is going to be tight too, again hoping to silence it as much as possible. Ultimate power isnt my aim here, 1 hp should be enough.

25 V LIFe PO4 battery is going to sit in an aluminum box slung below the chassis rails. Low capacity battery charged by IC driven generator, if it works.

Current thinking on motors is 6378 FLipsky skateboard motors, I guess these should be quite tough!

View attachment 270755
View attachment 270756

That’s frustrating, the pdf images are ‘pin sharp’ they go a bit fuzzy when you convert to jpg. I’ve not dimensioned them because I keep changing them and I’m lazy, i measure directly from the CAD model on screen using the measurement widget and draft a hand drawing for each part. Engine cooling is going to be interesting, current thoughts are to suspend a fast centrifugal fan drawing from a grille in the roof and blowing directly over the cylinder.

I think you would be better off pulling air in somewhere else (like near your motor(s) and use the vent above the engine as an exit, since heat tries to go up. You'd be fighting that to push the heat to some other exit otherwise, while heating everything up along its path out of the body.

I would treat the loco body as a computer case. Posititive pressure works best. So a push pull config. A couple intake fans with a single exit fan, while sealing everything else up as best you can. You could do that with some dryer vent tubing. But make sure the nitro gets the air flowing directly by it on its way out of the body. Or you could consider water cooling the head by wrapping a water tube around it. But then you'd still need a fan or two and a radiator. Look at 240 size AIO coolers if you want to look into it. Not sure if that would fit though. But you could find a small heater core out of a car and build your own cooler.

If you go the fan route, look at HP Server fans. They move a ton of air, are really loud, and would make your loco sound even more realistic

 

[Roog]

@Roog I love watching your work!

Cheers @Doom! The mechanics are a bit “doo hicky” but I am looking forward to introducing some RC gear to the project soon. Yet another Roog project with no means of steering! Seems to be a bit of a theme .