I am using a shapeoko 5 with a vfd spindle and carbide create. I am going to be cutting approx 300 wall switch cover plates using brass if I get this figured out. Approx thickness is 1.5 - 2 mm thick. Unless I am wrong I think c360 might be best. Does anyone have experience cutting these. My first attempt at metal. Bit choice, speeds n feeds? Thanks for any advice. I’ve attached an example.
2 Likes
I should be able to do some testing on feeds and speeds. The general approach to brass is something like aluminum speeds in CC and back off about 15%.
In a bit of serendipity, I need to replace some quickly done 3d printed wall plates in my own home anyway.
I’ve got high confidence you’ll be able to find feeds and speeds appropriate. The trickier part would probably be work holding. If it were just a couple, the usual tape tricks might work but at 300, that might just drive you insane. Maybe a vacuum table is worthwhile in this case 
I’ll try it with my switch plates and see how it turns out.
Out of curiosity, what are your raw stock dimensions and what kind of timeline are you looking to have these done in?
1 Like
For multiples which have holes in them, isn’t the best option to just use slightly oversize stock, clamp on a fixture w/ threaded inserts, machine the holes, put machine screws through the holes, then remove the clamps and send it?
FWIW, we did look into this a while back:
1 Like
Oh yeah that’s a solid idea. If there’s enough surface area, vacuum might get it done in a single operation, though with a decent torque limited driver the screws wouldn’t be so bad.
I wouldn’t want to mar the part by zipping in screws in a hurry 
@mountroop10 what are the hole sizes for those screws and do they need to be countersunk at all
Screw shaft 3mm. Heads are 6mm. Might consider counter sync
Just a tiny bit off subject: If you look at pretty much every light plate at your local big box store you will find the back of the plate is hollow as if it was an unbacked STL. This isn’t because they are cheap with material. It is to accomodate varying switch depths and the boxes which were installed decades ago…sometimes by unskilled non-electritians. (me). A flat backed plate will sometimes dissapoint in the final installation process as the switch body bulges out. My experience caused me to pocket from the back and leave the front alone, save a little touchup for the screws to fit flush. I see you are doing Decora, that’s probably better. I have always lived in old houses.
7 Likes
Does anyone know where i can source c360 brass sheets approximately 2mm thick? I am looking for large sheets
being new to brass cutting I am wondering which brass composition will cut the cleanest. From what i have read, c360 is best for free machining, however I cant seem to find larger sheets? Is c260 acceptable. My client is looking for a brushed brass look like the picture I posted in my initial thread.
Here’s one of two places to look. I’ve ordered from both and am a satisfied customer.
Bernd
1 Like
Midwest Steel and Aluminum has 36" x 96" x 0.125" C260 sheets.
1 Like
per your bit selection question. O-flute all day for brass on the shapeoko. I’ve been cutting a fair bit for leather stamps and have been very pleased with the stock oflute speeds and feeds for aluminum in carbide create. when you incorporate v bits is where you need to tweak some settings.
Workholding it needs to be solid. double sided tape is not enough. clamp the crap out of it.
2 Likes
Carve or 3D print a jig to hold them. Use double sided carpet tape to hold the material down inside the jig. I’ve done this with brass coins.
1 Like