CNC fillets

[valmeidan]

just curious it it possible to fillet around a part like this by machining it, and if so how? Or too costly? the piece is CDA110 copper pretty strong copper, and about 1.5x1.5 inches,.,

 

[ctopher]

The small fillet around the top edge?
Easy. Machinist's do this every day.

Chris, CSWA
SolidWorks 14
ctopher's home
SolidWorks Legion

 

[valmeidan]

how would they create that fillet?

 

[rb1957]

you could run a cutter (NC) around the corner. mind you, you could bevel the edge. or if it isn't critical, just a drawing note "break sharp edges"

Quando Omni Flunkus Moritati

 

[ornerynorsk]

Corner rounding end mill.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[ctopher]

Yes, corner rounding end mill.
Look up end mills with a corner round and see the sizes used so you are familiar with them.
A start: Link

Chris, CSWA
SolidWorks 14
ctopher's home
SolidWorks Legion

 

[BrianE22]

Yes, a corner rounding end mill. Try to choose a standard radius:

http://www.mcmaster.com/#end-mills/=tku6f9

You could also have the part tumbled. That will produce a radius around all the edges.

 

[valmeidan]

Thanks to all that posted I will look this up...

 

[KENAT]

Design for Manufacture Guidelines often discourage this kind of radii that is being created by the form/shape of the tool itself because each size radii requires a custom tool which may mean a tool change etc.

This is why chamfers are often used instead as the same tool can make multiple sizes of chamfer.

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[rb1957]

this fillet willadd to the cost of the part, maybe not much.

is it critical to the part's performance ? or is it "artistic" or just someone playing with the solid modeller ??

if not consider bevel (probably similar cost), or just breaking the sharp edges.

Quando Omni Flunkus Moritati

 

[ornerynorsk]

Corner rounding is often done in place of chamfering because a chamfer is still an edge, albeit obtuse. A radius lends to aesthetics and ergonomics and adds perceived value. The time spent machining is no greater than for a chamfer, and it would be unusual to mix multiple edge radii on the same part. It also reduces stress concentrations in more critical parts.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[valmeidan]

I would assume since this would be using a corner end mill that you would have to manually rotate the part along the edges to create the fillet around the part? or could this be programmed into a CNC machine tool path to do it?

 

[kingnero]

cnc does this for you
when correctly programmed...

 

[ctopher]

CNC will do the entire part.

Chris, CSWA
SolidWorks 14
ctopher's home
SolidWorks Legion

 

[BrianE22]

If you also have the fillet on the bottom side then the block will have to be flipped over.