Screw bootle feed making toolpath

[jonnyF57XN]

Hi try  make a infeed bottle screw to learn my new (old CNC lathe). my problem is that i cant make any toolpath for it. I'm a newbe in FUSION 360 and have it on trial for a month to evulate if its something for me. i can make simple drawing and make a post for G-code and it all works in the machine, but this is something i cant solve, is there any one who can point me in right direction for creating toolpath? thanks a lot for reading, and if you have any suggestions.

Best regards Jonny

[engineguy]

@jonnyF57XN 

Jonny

Best if you can upload your f3d file, go to File>Export to a folder or Desktop on your PC and then attach it to your reply.

You should be able to use a Profile cut using round profile tool for that job by selecting both edges of the spiral.

Regards

Rob

[jonnyF57XN]

Hi thanks for reply, here is my file. i will try your tip. and get back. BR Jonny

[jonnyF57XN]

Hi now i have tryed everything in my knoledge,  i attached my file with toolpath. and when i generate previev of toolpath i can see there is material left that i cant get ride of. where do i make it wrong?

Thanks in advance

[Anonymous]

In setup1 3D contour leaves uncut material in the middle, not sure what caused it.

Rotary in setup2 looks good but both of these need some serious computing power to simulate.

[jonnyF57XN]

Hi thanks! you put a lot knowledge in that i´m impressed. One problem that puzzle my brain,,, my lathe kan rotate the stock in any slow speed and back and forward. and the milling head can go out and in Y(or x depends on setup) direction and along (paralell) to z, but it cant go around the stock. so your setup learned me alot, but it doesnt do the trick, is there another way to do it? one of my idea is to move the milling head along the z axis while the stock is rotating slowly. is its possible? i tried for two week find out howto but no succes. some ideas?

Maybe your first setup is possible,  make pocket 1 rotate 120 degres make pocket 2 rotade 120 degres, pocket 3 rotate 120 degres countur 1 rotate 120 degres....etc but i didnot manage to create post without error..thanks a lot in forhand.

[Anonymous]

For start, your model far exceeds any mill-turn Y axis range that I have worked with in the past or present, general stroke of Y axis is +/- 2 inches and your model diameter is in 6 inches range, that makes for big bottle cork screw.

If there was no taper in diameter, you could use 2D contour or 2D pocket to wrap tool path, but because of taper, you cannot, wrap only works with fixed diameter cylinder.

You also have variable fillet on one edge so it is job for 3D tool paths and ball end mill.

Using tool orientation, I divided part in 3 sections, each would result in indexing C axis, you would machine each segment at 0, 120 and 240 degrees respectively, inner radius is set to have each tool path overlap the other resulting in complete circle.

I cannot post setup1 due to out of limit range, I can post rotary setup because it only uses X and C axis. 

I have Lenovo P72 workstation laptop with 40GB ram, i7 intel processor and Nvidia Quadro P2000 graphic card, all SSD and simulating this part slowed it down significantly but it produced clean result if I cared to wait that long.

3D contour left unfinished stock in the middle and that is something I can't explain, perhaps one of the wizards from Autodesk can tackle that one.

[Anonymous]

One correction, rotary tool path in setup2 uses X,C and Z axis. Tool is driven in X and Z axis while C axis is continuously spinning. 

[jonnyF57XN]

Hello, Thanks a lot for helping me think. yes its a big file and it consum lot of computer power.

i realized that the 120 degrees rotade does not work i cant move the mill out of centerline......dead end..

But you give me another idea.

I will try to explain:

look from the side of the srew and ther will be countur. make the countur as a toolpath. mill down to bottom stock is not rotating.

.

rotate (i guess 2) degrees, make new countur. mill down

rotate 2 degres make a countur mill down
rotate 2 degres make a countur mill down
rotate 2 degres make a countur mill down
....and so on

and so on to a hole  360 swing, my lathe can make index..

What dou you think of that solution?
if it possible i dount now and next is to make fusion 360 to work it out.
any idea is welcome, thx Jonny

[Anonymous]

---

@jonnyF57XN wrote:

Hello, Thanks a lot for helping me think. yes its a big file and it consum lot of computer power.

i realized that the 120 degrees rotade does not work i cant move the mill out of centerline......dead end..

But you give me another idea.

I will try to explain:

look from the side of the srew and ther will be countur. make the countur as a toolpath. mill down to bottom stock is not rotating.

.

rotate (i guess 2) degrees, make new countur. mill down

rotate 2 degres make a countur mill down
rotate 2 degres make a countur mill down
rotate 2 degres make a countur mill down
....and so on

and so on to a hole  360 swing, my lathe can make index..

What dou you think of that solution?
if it possible i dount now and next is to make fusion 360 to work it out.
any idea is welcome, thx Jonny

---

Good luck with that .....

Rotary tool path in setup2 does not require Y axis,....... but given the size of it, you would most likely need to drip feed program, lathes don't come with abundance of memory, especially the old one's.

[jonnyF57XN]

Sorry if I'm not understanding solution number two, in my program the mill tool is circulation round the stock, but do i understand it correct? if so it wount work. my spindel is fixed in that way. but if the stock circulating and mill head gous out and in and sideways it works. And memory is no problem i did an uppgrade on program and servon. thanks for you patience.

[Anonymous]

OK, setup1 is for machine that has Y axis and setup2 can run on machine that has Y axis or only C axis.

Does your machine have Y axis?

Going back to your idea with contours at 2 degrees increment,........ you would need 180 contours and if you can produce accurate tool paths, result would look something like saw blade because at 2 degrees increment, step over amount would be too big and very in value depending on diameter, passes would not be coordinated for smooth finish.

BTW, nothing of a kind hes ever been attempted to best of my knowledge and no one should ever attempt it because it cannot work.

Now, setup2 does exactly what you proposed with multiple contours but it does it in a way that produces uniform finish.

If your lathe does not have Y axis, this is the way to do it.

[engineguy]

@jonnyF57XN 

Yes, it is a bit confusing in the simulation, it does show the tool rotating around the stock but in reality the stock would be rotating and the tool would just be moving up and down in the X axis on a Lathe, so, from my limited knowledge of this project I would think that no Y axis (You are not cutting across the part) would be in use for the rotary, only Z moving along the part and the X moving in and out and the C axis doing the rotation, just a matter of finding the right Post Processor to produce the code needed.

I have tried a Doosan Fanuc 31i post and it looks pretty good, starts off with a full X and C rotation and then goes to X and Z and C moves together which I think is what you need to Spiral along the length of the Part, so if you have a Fanuc based control this post may work for you with a few "tweaks" 🙂 🙂

Files attached.

Regards

Rob

[Anonymous]

To post (setup2) for C axis only, set Doosan post to Lynx in user parameter window.

[engineguy]

@jonnyF57XN 

P.S. I forgot to mention, you will be making pretty deep DOCs so would have to go very slow with small tool, I looked at doing several passes at reduced depths and I found that I could set "Stock to leave" at say 10mm Axial, then duplicate the Rotary operation and set the next one to say 5mm "Stock to leave" and the last one at the finish setting of 0.5mm, so a bit of a workaround to use a bigger tool, say 12mm Ball nose and higher feeds and bigger stepovers to remove the bulk of the material with only the finish with the small stepover producing the big code.

Just a thought 🙂

Regards

Rob

[jonnyF57XN]

Ok now we talking... i did a fancy and quick drawing of my movement of the machine and attached it. I´m not so used to axiz labeling in the mill worls, i´m a lathe man. so please correct me then i can print it on the wall. Thanks for patience.

[Anonymous]

Rob, setting small value as step over in roughing removes bulk of material in same fashion as adaptive clearing with optimal load set to small value.

[jonnyF57XN]

PS this is so cool if it works thanks a lot

[Anonymous]

Can anyone explain why there is uncut material left in finish pass along middle of each 120 degree segment?

[johnswetz1982]

Does same happen if you use 60 degree increments?