"Brass" plaques

[JAZZCNC]

You reckon I'd be OK ??? - don't want to knacker my machine to be honest. My long term plan would be to engrave a brass plate as a clock face (that would have to be a good quality brass) but had thought I'd have to use some other technique like photo-etching instead. I fiddle with clocks and watches and if it helps with that - It's a real win. To be honest I thought I'd need something with more oomph.

The video shows him going to a depth of 0.1 mm - is that the secret ? - lots of sweeps at very shallow depths ??


I'm still very new to all this stuff - being able to cut brass and aluminum would be a definite plus. All advice gratefully received

Well without knowing your machine it's difficult to say how it will handle cutting brass, but if you chose the right stuff and take it easy on DOC then can't see why you shouldn't be able to engrave or cut brass without any troubles. You want something like CZ120 which is a free-machining brass and a nice carbide engraving bit.

Also if you are not engraving deep then look at using a diamond drag bits. This doesn't apply many cutting forces on the machine and doesn't require a perfectly flat bed or material surface as the spring-loaded tool adjusts to suit. If your planning on engraving without spring-loaded tool then make sure your bed is sufaced perfectly flat.

[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