Round a steel edge question

[Jim F]

Another idea, bolt a washer of your desired radius as a guide to grind away.

 

[MrWhoopee]

That's one operation that a standard milling machine can't do easily-
Pretty much have to saw and then grind/file like Larry$ said

Excuse me!?

Regarding the OP, I always do it with a belt-sander. Good excuse to buy another tool.

 

[SouthernChap]

Recent video by Blondihacks about making filing buttons:

 

[dml66]

Another idea, bolt a washer of your desired radius as a guide to grind away.

Another "why didn't I think of that" moment, thank you!

 

[dml66]

Lots of great ideas here, thanks to you all!

I should've added angle grinder and air cutoff tool to my list of what's in the chest. Also, have a 5" P-C disc sander I can use for cleanup.

 

[savarin]

check this out

The Giant Binocular

I rounded the ends at 500rpm with the 12mm end mill. Thanks to Bob Korves for suggesting the speed. Virtually a hot knife through butter. all 6 done with the handle I used as an aid. To weld them to the base I clamped a length of steel to the legs as guide to keep the angles correct...

www.hobby-machinist.com

scary to think about but easy peasy in practice.

 

[MikeInOr]

I'd like to round the end of a mild steel bar like I did the aluminum prototype beside it in the picture.

The aluminum one was done on a table-mounted router with a ball-bearing quarter round bit.

I don't have a mill: I do have a mini-lathe, drill press, bench grinder, metal cutting bandsaw, and metal dry cutting chop saw.

Any ideas for a way to take the vertical sharp edge off the steel bar somewhat like the aluminum?

Thanks

View attachment 469284

I would rough in the rounded corners with the grinder then finish them with a file.

Like others have said a disc/belt sander does a great job for this.

Neither the grinder / file or disc / belt sander will give you perfectly radiused corners but it shouldn't be very difficult to get rounded symmetrical looking corners to the average eye.

 

[RaisedByWolves]

That's one operation that a standard milling machine can't do easily-
Pretty much have to saw and then grind/file like Larry$ said

Two words:

Corner rounding end mills.

 

[Larry$]

I think there is confusion about which radius we are talking about. Not the edges but the end.

Corner rounding end mills.

 

[RaisedByWolves]

I think there is confusion about which radius we are talking about. Not the edges but the end.

No confusion at all.

Edge, end, inside a pocket, they work wherever you use them.

Unless your confusing them radiused endmills?