Question for machinists

[D-fens]

What end mill or cutter is used to create a radius like in the pic above?

Preferably something that could be used on a mill not equipped with a rotary table.

Thanks in advance.

 

[NASTYZEN]

There called radiused end mills. Check with a machine shop suppliers like KAR.

 

[A_Pmech]

I often use corner rounding router bits in a handheld router for finishing holes like that in aluminum. It's a two-******** and I won't dare climb cut, but it's a whole heck of a lot faster than setting up a rotary table for each hole.

I won't go much over 1/4R by hand though.

 

[Kevin54]

It's done with a corner rounding end mill, but it's all dependent on what size of hole is through the material and what size of radius it is, as the corner rounding tools are pilot size specific.

What are you looking at doing? It would be easier to answer as to how you may go about it.

 

[D-fens]

It's done with a corner rounding end mill, but it's all dependent on what size of hole is through the material and what size of radius it is, as the corner rounding tools are pilot size specific.

What are you looking at doing? It would be easier to answer as to how you may go about it.

Building a short runner intake for a turbo car. Need to bore and radius six 1.75 (aprox) holes in a piece of 3/8 or 1/2" plate.

I found a thread covering the how-to on VW Vortex (where I stole that pic from) but one, the guy didn't specify exactly what the tool was called, and two, it looks like he's no longer active on Vortex - not that I blame him - so I doubt I would get an answer.

A_Pmech - haven't ruled out what you suggest, but since I have access to a vertical mill I thought I'd try that first.

 

[bullnerd]

No rotary table, no CNC = hand held router.

 

[Kevin54]

With a 1.75 diameter bore, it will take a rotary table, or else a special cutter to do it. If you are interested, send me a PM and I'll make you a hell of a deal for machining them.

 

[iajonesy]

I would be more inclined to say that was done on a cnc with a boring attatchment. It looks too smooth to be done with a radiused end mill. Just .02 cent worth.

Mike

 

[PugetDude]

If it's aluminum, you should be able to radius a bored hole with a sharp carbide roundover bit in a big handheld router. Take a small bite, go slow, and don't try to climb cut. It will take multiple passes to get to depth, but it won't take long.
Easy to experiment...

 

[rsanter]

custom blade in an adjustable flycutter.

Make your radius in a standard blade.

This or use a round over bit in an adjust adjustable boring head

Bob

 

[bullnerd]

I would be more inclined to say that was done on a cnc with a boring attatchment. It looks too smooth to be done with a radiused end mill. Just .02 cent worth.

Mike

Too smooth?....the whole thing is chatter.

If CNC, you dont need a boring attachment, just a roundover bit.

Pretty common operation really.

I noticed you said you have a milling machine, I didnt see that in my earlier post.

So you can make a custom "form tool" , many different ways, or buy the right size radius cutter (cheap, could be a router bit) and figure out how to hold it. Again could be many different ways. Can you weld? Space it out and weld it to a shaft. Lay it down and weld it to a shaft. Many different solutions. Think about it.

If your only doing one part....router is tough to beat.

 

[Guster]

Ditto on the form tool in a boring head if it is large, corner radius end mill or custom ground counterbore if it is small'ish. Rotary table is also handy for the latter. Router is one option if a little sketchy for a big cut. If it is large you can relieve it in steps on the mill first and do the final cut with a form tool or router

That chatter ripple looks like it was done in one op with the same tool.

 

[Grigg]

...use a round over bit in an adjust adjustable boring head

Bob

Yep, that's what I do, and or grind a tool to suit and still use in the boring head for easy adjustment.

 

[bullnerd]

Yep, that's what I do, and or grind a tool to suit and still use in the boring head for easy adjustment.

Yup,yup....now, does the OP have a beefy boring head?

 

[mattygee]

For simplicity and time I would go with A_P Mech's solution. A carbide roundover bit with a guide bearing will do each hole in about 30 seconds with no setup required. Brass and aluminum can be successfully cut/shaped with a lot of woodworking type power tools.

 

[petawawarace]

Router would be the easiest for a few pieces. You could make that with a custom ground cutting tool and a 4 jaw chuck on a lathe (depending on size of the part) on a mill with the boring bar, fly cutter, rotary table, or cnc mill or cnc lathe it. Many ways to skin a cat. But again I would say the router is easiest

 

[D-fens]

Thanks very much for all the replies and input.

The tooling we have for the mill / lathes is minimal. I don't know what we had to begin with, and whether or not fellow employees toted it home one piece at a time, or if it went to the pawn shop like a lot of tools and equipment that used to be here. Nuff said.

I don't have a boring head, but I will at least take a look at the Hazard Freight rotary table. Though I don't know how that would work with a piece of 4x1/2" aluminum flat bar about 18" long.

I'm considering grabbing up a router bit, a few pieces of 1/2 and 3/8" stock, practice up a little, and see how that works before making the actual parts. If the results **** I will contact Kevin54 and have him make a couple for me.