"Brass" plaques

[timtoo]

I have successfully machined and engraved brass on my scrapyard CNC build, it has a cheap 500 watt Chinese brushless spindle. I have had decent results using a tiny center drill as an engraving bit.The lettering is a test for the dial of the Orrery I am building is 1.6mm high.



You do need to make sure the workpiece / table is dead flat, just bolt a piece of sacrificial aluminium plate to the table face it off and stick down the brass with super glue/ masking tape. The red stuff from Wilcos is great, any gel super glue will work.

As Jazzcnc said make sure you get CZ120 brass, I had really bad finish using unknown brass from the scrappie.
It did cut but I needed to do loads of test cuts to get the feed and speed correct.

Here is a gear for the Orrery, 40mm dia. from 3mm brass, apart from taking off the burr round the edge it's straight off the machine.
Note: only the spokes were done on the CNC I cut the teeth on a manual mill with a DIY digital dividing head.



Take a look at the Carbide Create Youtube channel loads of good stuff there for us hobbyist dabblers.
Winston Moy is a wizard, in this video he is using the Nomad which only has a 75 watt spindle............

https://www.youtube.com/watch?v=mhqjhD0XJl0

For Ali. see the amazing stuff that Vince Ramirez is doing.

https://community.carbide3d.com/t/ha...-on-an-s3/9744


https://carbide3d.com/spotlight/vincefab/

I am a real noob with all this, I just got some cheap ebay cutters and gave it a go.
You should too.

Tim

[Britannicus1]

Inspiring work there Timtoo. One of my aspirations is to make a really satisfactory astrolabe. I have SVC files for the engraving, though somehow fusion 360 scrambles them up a bit . I also fix clocks from time to time, I hadn't thought my cheapo Chinese cnc would e up for the job - just playing with the technology at the moment. I got the point about brass, and the speeds and feeds - what would be a good set to start with to experiment ? I'd figured a slow feed rate and my fastest (8000 rpm) rotation would be a start

[timtoo]

I got the point about brass, and the speeds and feeds - what would be a good set to start with to experiment ? I'd figured a slow feed rate and my fastest (8000 rpm) rotation would be a start

Hi Britannicus
I started with the feeds and speeds from Winston Moy in the Carbide 3D video from the link in my previous post
Run a couple of tests and see how they go for you.
I found I could use between 7,000 and 10,000 RPM and get good results, with the spindle on manual control I just turned up / down the spindle speed until the cut looked / sounded better.

Tim