Any Luck With Less Expensive End Mills?

[China Woody]

I've had some success cutting 2D and 3D images in brass with my small X-Carve and Stepcraft machines, making medallions for renaissance fairs. I started with Amana Spektra and ZrN-coated end mills, and finally got to very conservative cut speeds and widths that get the job done, and don't often break bits. But when it does happen, it is very discouraging, as the bits are in the $40 range.

Has anyone had any good experiences cutting non-ferrous materials with less expensive bits? It would be nice to find a source that would make it less traumatic when things go wrong.
Thanks.

 

[Rick Mainhart]

Hi John,

It's a bits kind of night!

You probably need to look at end mills designed to cut the materials you are working with. While you can cut brass and other softer materials with woodworking router bits, the cutting edge geometries are different.

As mentioned in another message, take a look at Bits & Bits and see what they offer. Others may have alternate sources they can share (hint hint).

Onsrud is another good source, and I had lengthy discussions with them when I was cutting HDPE with the ShopBot CNC (a long time ago btw), and had a very good discussion about optimum chip loading, depth of cut, and how to calculate the proper feeds and speeds (for the HDPE it was to obtain a 0.007" thick chip for maximum heat transfer and minimum bit deflection, and at a reasonable production rate).

For cutting copper-clad fiberglass circuit boards at work, we had used TiN end mills designed specifically for the purpose (and cut dry with only vacuum cleanup) ... there may be some newer coatings available ... these were all 1/8" diameter shanks and only ran about $7.00 each. We'd toss the end mills when they started plowing the copper rather than turning it into fine copper dust ... and generally if you watched the process, you could swap out the tool before it broke (saves material).

Regards,

Rick

 

[China Woody]

Rick, thanks -- good info. I've been using ToolsToday for the Amana stuff. Have you had good luck with any other sellers?
Thanks again.

 

[Rick Mainhart]

Hi John,

Not off the top of my head. I've retired, but can check with my friend that is doing the PCB milling to find out who he's getting his end mills from, and what coatings he's using. Mind you, this is for copper ... brass may have different requirements (though the supplier will be happy to tell you).

Will 1/8" shank end mills work for you?

Regards,

Rick

 

[China Woody]

Hi John,

Not off the top of my head. I've retired, but can check with my friend that is doing the PCB milling to find out who he's getting his end mills from, and what coatings he's using. Mind you, this is for copper ... brass may have different requirements (though the supplier will be happy to tell you).

Will 1/8" shank end mills work for you?

Regards,

Rick

Thanks, Rick. I've done most of my stuff with 1/4 inch shank before, but I've got reduction sleeves, so it shouldn't be a problem. Maybe that's what I should be looking for, as a way to reduce cost? I've tried to cut copper before, and yes, the characteristics are different. It was much harder to get a good cut, so I went back to using mostly brass.

 

[mkepke]

Not much experience to offer but check out the eBay seller drillman1. Offers a wide range of end mills usually Kyocera brand often USA made. Bits for metals, plastics, woods, etc.

You'll save money if you use 1/8" shank where possible. And a 1/8" collet instead of a reducer - less slippage, less run-out.

-Mark

 

[China Woody]

Not much experience to offer but check out the eBay seller drillman1. Offers a wide range of end mills usually Kyocera brand often USA made. Bits for metals, plastics, woods, etc.

You'll save money if you use 1/8" shank where possible. And a 1/8" collet instead of a reducer - less slippage, less run-out.

-Mark

Mark, thanks for your comments and advice. I think you're right. I'll check out drillman1, and see if perhaps 1/8" shanks are the way to go.