Westlake Publishing Forums

It already looks impressive!

Cool!

I love 'em! They'd be right at home in so many small mining towns in the western USA.

More from 'The exception proves the rule Dept.'...

A facebook group I belong to popped up the attached images in the last couple of days.

The Mangaweka building had a comment from a previous owner to the effect that the bench out front was placed there as a way to escape the chill of the interior.

Not that this in any way changes my feelings about whole towns of such structures appearing unrealistic.

Yes, that definitely needs to be modelled.
Les

Adequate. -- Russ

For this third engine I decided to make some small improvments on the trucks, so I milled the holders for the spring hangers from solid brass instead of forming them from strips of brass.

But these buggers are small, just 1.6X2X2mm. The biggest problem with milling such parts are holding them firmly in place during the machining process.  For bigger parts i mostly use two-sided carpet tape for holding, but for thes parts the holding area is way to small.

So I started by soldering a 10X60mm piece of 1,6mm engravers brass to a 10X10 bar of brass. A brass bar like this soaks up a lot of heat, so i used a large propane torch for heating up the parts. For solder I used Carrs 179deg. solder cream.

The brass bar was then placed in a small machine vise.

First operatian was drilling the 0.8mm holes. This was done with a feed of 2mm/sec. The holes were "peck-drilled" 0,4mm at a time.
Then a 3-cutter 3mm flat endmill was used to mill the parts. Feed was 3mm/s, spindle speed "5" on the Kress motor  wich i guess is 25000 rpm. 

I used some spray-can machining oil that seems to make maching brass a little easier, even if most folks say that brass can be machined dry. 

There was a little burr on the parts, but it was easily sanded off with some grade 400 emery paper.





PS: As mentioned before, these parts are small, and in a flash of foresight I made 6 more holders than needed!

Quote from: Bernhard on November 22, 2023, 12:29:04 PMFor parts that are just lying around as decoration, the truck sides look really good.

Bernhard

They are indeed built for laying around looking gorgeous in the workshop, but as I have revealed in another thread building this is also a way of tricking myself into building the last of the three engines of this tyoe that the Thamshavn Railway operated. So all stops will be pulled for building the engine parts!

Quote from: Bernhard on November 24, 2023, 02:01:41 AMThanks Kim, Russ and Hauk.

Hauk, I use two types of brass:

• Ms 58 (CuZn39Pb3) hard for flat and round material. The material is very easy to machine.
• Ms 63 (CuZn37) semi-hard for sheet metal. The material is easy to cold form.

I purchase the material from a local dealer.
I am relatively careful with the cutting values when milling. Under no circumstances should you use the values recommended by tool manufacturers for industrial use. I run the spindle at a maximum of 10,000 revolutions. Otherwise, because it is only air-cooled, it heats up too quickly.
I normally work with 2-tooth cutters with a diameter of 3 or 4 mm at a feed rate of 50 mm/min.
You have to work your way up a bit from the bottom. The optimum cutting data certainly also depends on the stability of the machine.

Bernhard

Thanks a lot for the info!

I see that you too use very slow feeding, and it seems this is the key to success when milling metal on relatively light CNC-routers.

Thanks Kim, Russ and Hauk.

Hauk, I use two types of brass:

• Ms 58 (CuZn39Pb3) hard for flat and round material. The material is very easy to machine.
• Ms 63 (CuZn37) semi-hard for sheet metal. The material is easy to cold form.

I purchase the material from a local dealer.
I am relatively careful with the cutting values when milling. Under no circumstances should you use the values recommended by tool manufacturers for industrial use. I run the spindle at a maximum of 10,000 revolutions. Otherwise, because it is only air-cooled, it heats up too quickly.
I normally work with 2-tooth cutters with a diameter of 3 or 4 mm at a feed rate of 50 mm/min.
You have to work your way up a bit from the bottom. The optimum cutting data certainly also depends on the stability of the machine.

Bernhard