milling question, 80 degree V groove

[X-Rated]

If I had a mill, and wanted to cut an 80 degree V notch how would I do it? If It was a 90 degree notch, I could just tilt the head 45 degrees and use an end mill, but I need a notch that is less than 90... Do I do the same with but with a 60 degee cutter and just tilt the head 10 degrees one way and then 10 the other?

[Cork]

Could a 80 degree cutter for a horizontal mill be used if an adaptor was made to chuck it up? Then just put the work on its side.

[Toddy]

Why not tilt the head 40 degrees? Or make you a jig to hold the piece you are cutting at the angle you need.

Toddy

[PTSchram]

Why not tilt the head 40 degrees? Or make you a jig to hold the piece you are cutting at the angle you need.

Toddy

Because the bottom of the cutter would be cutting at 90', not 80'. Best case with your setup would be to use a tiny cutter and cut a relief at the peak of the groove.

A formed cutter with an 80' angle would likely be the easiest but not necessarily the least expensive. Think shell mill.

[JeffHPK5]

Our tool room at work is privileged to have a very skilled cutter grinder hand so custom profiled tools are usually no problem for me..but..

If he's off and I needed to make a cut like your describing I would take a end-mill to the pedestal grinder and clear the flutes at an included angle less than the 80* your trying to attain....make a cut with the bottom of the E-mill then flip the part ...cut again to your desired angle.

Think dovetail cutter..:smokin:

Jeff

[PTSchram]

If he's off and I needed to make a cut like your describing I would take a end-mill to the pedestal grinder and clear the flutes at an included angle less than the 80* your trying to attain....make a cut with the bottom of the E-mill then flip the part ...cut again to your desired angle.

Think dovetail cutter..:smokin:

Jeff

Wouldn't this limit the depth of cut? I'm assuming you're talking about cutting inward from the face of the cutter, angling inward toward the shank.

[JeffHPK5]

You'd be limited to the cutter dia. as your single pass depth. I was picturing this being like press-brake tooling for the female die section ?

I've hacked a 1" 4flute Emill to taper down to 1/2"dia. at about 1.5 up the flute , not great but it worked..:smokin:



A keyed arbor cutter or ground form tool would be ideal but sometimes you need to do stuff thats less than pretty!

[Ghetto Fab.]

Don't know if this would work for you, but you could cut a grove with an endmill straight down along the length of your part. Then using a smaller end mill tilt the head 40* and cut one side. The bottom of the endmill would be in the grove and clear of the opposite side. Turn part around and cut the opposite side. You'd have to do some figuring to figure out what cutters and depths you need, but it'd give you an 80* slot.

Kevo

[X-Rated]

I think this is the answer. Cut a small slot right in the middle of the V, then tilt the head. It wont give me an 80 degree sharp pointed V, but it will let me get a 80 degree V with a 1/4" or so flat spot in the middle.

[JeffHPK5]

Until he posts otherwise I was "assuming" he wanted a sharp corner (V) with no extra groves or radi. in the gullet.

Edit: If a sharp corners not needed then this shuold be easy... good luck.

[PTSchram]

I think this is the answer. Cut a small slot right in the middle of the V, then tilt the head. It wont give me an 80 degree sharp pointed V, but it will let me get a 80 degree V with a 1/4" or so flat spot in the middle.

Don't know if this would work for you, but you could cut a grove with an endmill straight down along the length of your part. Then using a smaller end mill tilt the head 40* and cut one side. The bottom of the endmill would be in the grove and clear of the opposite side. Turn part around and cut the opposite side. You'd have to do some figuring to figure out what cutters and depths you need, but it'd give you an 80* slot.

Kevo

This is what I meant by cutting a relief at the peak of the groove.

[D60]

Aren't production drill/mills 90 included? Seems like w a steady hand you could grind 'em back to a semblance of 80. But yeah, depends upon just how deep/wide you need this v-groove to be and if you can buy a drill/mill large enough.

[JeffHPK5]

It takes a pretty skilled person to free-hand sharpen the bottom of an Emill... and have it do anything other than rub :laughing:

Also the max flat you could achieve would be half of the cutter dia. on one side of your "V".... it would look more like a check mark than a "V".

I thought about this thread at work today, I had to make a 70* included "V" in a bar of alu.... roughed as much out as I could with a standard 3/4" rougher and used a fly cutter to finish.

Flats of the "V" where 2.125 in length.

[rideonjon]

if it needs to be a v at the base and no clearance groove is allowed grind a peice of HSS to 80DEG put into fly cutter and use it like a slitting saw.

[X-Rated]

Like mentioned above, I am trying to replicate a lower V die for a press brake. I cant seem to find any of the 4 way ones online to buy...

Although, the lower part of the die doesnt really need to be a V, It could just be a rectangular notch out of a piece of steel. the only thing that matters is the width at the top and the depth needs to be great enough to get to 90. The V's make it easier to get 4 different widths on a single block of steel though.

[guy,sxj]

Using a 4 flute 60º countersink grind some clearance on the back side with a hand grinder. Tip the head +10º, cut, then -10º re-center, cut.

[p14175]

Split the "V" in half, machine two pieces 40-deg each and then bolt them together?

[Brian Ellinger]

Why not a 45 or 60 degree cuter and a sine bar, rather than tilting the head (and having to reset it)

[JeepButcher]

At work we've gotten decent results doing v slots using carbide spot drills and they come in various angles. Of course we really don't do that any more because it's slow and sucks ass. Now we just order any tools we need.

Edit: Oh and it also doesn't give you a sharp V it more of a flat bottom