[cncsdr]

how would i program a cone 3inches at top 1.7 at base angle 35degrees

[Geof]

Lathe or mill?

[cncsdr]

mill vf-2

[Geof]

I wondered; lathe is fairly simple but mill is not. It is beyond my present ability and I am interested to see what is suggested because I have in mind some parts that will need it.

[psychomill]

3.0" at top, .... 1.7 at the base,.... 35deg angle.

So you have an upside cone? Is there a plate at the base? Basically, is it just a cone, or is there more to this part?

If its just a cone, then its a cake walk. You can do it on a rotary table (if you have one), or you could stand it up with the small end up and cut it in 3D. Which in reality, you don't even need full 3D, you can cut the part in 2-1/2 axis (G2 or G3 arc moves with an XZ or YZ stepover).

[miljnor]

is it the math your having problems with or the actual programing?

Because programing the, part lets say from the top down, (like psychomill said "small end up") is just integrals from a 90 degree triangle, with the top (or smaller angle) of 35deg, with with every step over calculated by how far in the Z direction you go (trig it out) this is how much the radius of you circular move will change for every z step.

I have calcualtors for this, but in a pinch I could give you all the formula. I am sure someone with a higher order frontal lobe could probably give these things to you quicker. afterall its been about ..... well a few years for me!

[Brian J]

Or even nastier yet if you have Haas Macro let the machine do the math and you can set the step down however you like by just changing some variables.

[Kool Parts]

cncsdr,
Is this the shape you are looking for. Allways a good place to start! :idea:
Gary

[Kool Parts]

If so it would go something like this. There are several more pages but you get the idea.
Gary

[miljnor]

or if you wanted to get trick you could do a downward spiraling helix! Have fun programing it though if you don't have a cad/cam system.

[Geof]

or if you wanted to get trick you could do a downward spiraling helix! Have fun programing it though if you don't have a cad/cam system.

This is what I am waiting for someone to post; but not the cad/cam version a generalised macro routine is what I want. Enter top diameter, bottom diameter, height, pitch of helix - push button.

[miljnor]

not asking much are you! I see what i can do but it will take me awhile. Hopefully someone beats me to it (as I am pretty slow in the macro coding) but I can do it..

your not in a hurry are you? tired :tired:

[screensnot]

The attached pic is from a Fanuc manual. I don't know if Haas can do it or not.

You only need to program one of the three values that are in the parentheses. The other two will be figured out by the control.

[miljnor]

I have never tried that but I think it will work. Will try it Tomorrow at work.

[HuFlungDung]

Michael T,
Let us know if you make a discovery on the Haas. I doubt that it will work on a G02 or G03, but it might work on a G13 helical.

[miljnor]

dont you have HAAS in your shop Hu?

never used a g13 does haas support that?

dont have my book at home!

[gar]

050916-1453 EST USA

G13 on a VF is Circular Pocket Milling Counterclockwise.

This starts at the center, arcs out as shown in the HAAS illustrations, and at the end arcs back to the center. I believe the first and last motions are arcs, and the middle area is a spiral. G13 won't work for this application unless the cone is a cavity with large open end at the top.

If a machine has a true sprial capability, then one instruction would make a cone. I do not believe HAAS has such a capability, whereas I believe Fanuc does, or partially does.

Thus, on HAAS you make a lot of short straight segments, or arcs, or you use a lot of circles. Any of these can be done with relatively little code in macros.

.

[miljnor]

I looked at the book and Gar is right on. Probably the best way to do this is with a macro that vari's the arc and the depth of spiral using a g2 or g3. Which is what I am working on. Virtual gibs does this for me with a plugin that does tapered pipe threads. After seeing a couple of example outputs for the tapered thread it is fairly easy to make a macro for it. After I rember which trig function to use I will put it here.

[Geof]

.... Virtual gibs does this for me with a plugin that does tapered pipe threads....

Why can't you just use this to make a very fine pitch thread with a very steep taper?

[HuFlungDung]

The Haas manual doesn't address a conical interpolation that I can find, but I was wondering if there were any undocumented moves that it can be tricked into making. I have not attempted to find out thus far on my own machine.