PDA

View Full Version : Help with tapered holes



tinmanpk59
04-05-2020, 02:03 PM
Hello All
I have been trying to get my head round cutting out tapered holes via Vectric VCrave Pro without success and I am after some pointers. I want to be able to rough out the tapered circle pocket, then do some kind of helix interpolation down the tapered sides to smooth out the steps. Would be helpful if I could do this in VCrave, but if not an example in pure G Code would do.

Neale
04-05-2020, 08:11 PM
One of the restrictions of Vcarve is that while it is great for 2D/2.5D CAM. it can't do this 3D kind of thing. Unfortunately, it's not straightforward in gcode either. If you use the G2/G3 arc/circle commands, you can either cut a circle at a single depth, or cut a circle with steadily increasing depth by advancing in Z while cutting the circle with constant radius. No tapers.

I would suggest that you could look at Fusion 360 which has a full CAM capability which would produce this kind of gcode. There is a bit of a learning curve involved (depending on where you are coming from - this could be an understatement!) but it could do what you want and it's free for home and hobby and small commercial users.

Voicecoil
04-05-2020, 09:36 PM
One thing that might help (if it goes to the sort of angles you're looking for) is the Vectric chamfer plug-in/widget or whatever they call it*. It's meant to be able to cut chamfers of any arbitrary angle using e.g. a ball nose cutter, you can adjust the smoothness apparently by setting the step-over. I'd be interested to know how you get on with it as I have a project coming up which is going to need a lot of strange angles cutting.

* https://gadgets.vectric.com/V8/chamfer.html

tinmanpk59
04-05-2020, 09:46 PM
Never tried that, will give it a go. Thanks

tinmanpk59
04-05-2020, 09:48 PM
May look into that if there is no other option. Cheers.

phill05
05-05-2020, 02:03 PM
Here one to try,
Example to draw a ER32 collet holder: Draw out your largest circle say 32mm dia within draw smaller circle say 25mm dia, draw another circle say 17mm Dia, draw a vertical line 9mm long starting top of largest circle down towards centre select and circular copy this say 400 times ( the more lines you copy the smoother the finish) x 360 degrees.
Select smallest circle "pocket toolpath" to full depth say 36mm,, select all circular copied lines "Fluting tool path" run preview job done.
Hope it helps.

Phill

28057

28058

28059

28060

28061

tinmanpk59
05-05-2020, 04:36 PM
Thanks for that, will look into that.

tinmanpk59
05-05-2020, 05:18 PM
Have tried your idea out in VCarve, its a nice one but takes too long to generate the hole. And my machine will not take a massive ramp up in speed and feed rates to reduce the cycle time to a respectable level. Pity because I like this approach. Thanks for the input.

Voicecoil
05-05-2020, 09:05 PM
Another way of doing it (particularly if all your holes have the same angle) would be to get a custom cutter made - best shape might be an endmill with angled sides I guess? If this appeals I'll have a word with my luthier friend Mike who had some made recently - but they won't be ultra cheap.

tinmanpk59
05-05-2020, 10:58 PM
Have tried to use the plug in chamfer program in VCrave 10 but it keeps bombing out with various errors with my system so no joy there. Had looked on the net for a cutter. The nearest I came to what I need is a 7 degrees cutter, will have to workout what the difference is in diameter between the 8 degrees and 7 degrees then go for the cutter to make the smaller holes and opening up the rest with the same cutter.

phill05
06-05-2020, 06:09 AM
Have tried your idea out in VCarve, its a nice one but takes too long to generate the hole. And my machine will not take a massive ramp up in speed and feed rates to reduce the cycle time to a respectable level. Pity because I like this approach. Thanks for the input.

You can put less lines in I copied 400 times for a 12mm end mill to give you a superfine finish less would be quicker, play around until you find best to suit your setup.
Plug in "chamfer" only works in V9 I think.

Phill

the great waldo
06-05-2020, 11:41 AM
Maybe you could use a taper pin reamer. There are plenty about on the web but you might be a bit limited with angles. Or something like this
https://www.toolstoday.com/3-5-7-patternmakers-plunge-bit.html
What do you need the tapered holes for.
Cheers
Andrew

Voicecoil
06-05-2020, 02:40 PM
Take a look here, they do 7 degree cutters:

https://www.drill-service.co.uk/products/milling-cutters/conical-tapered-milling-cutters/

not ultra cheap, but I'm told their quality is good.

tinmanpk59
06-05-2020, 09:20 PM
Thank you for the link, will check it out.

Arron
17-12-2020, 02:36 PM
Hello All
I have been trying to get my head round cutting out tapered holes via Vectric VCrave Pro without success and I am after some pointers. I want to be able to rough out the tapered circle pocket, then do some kind of helix interpolation down the tapered sides to smooth out the steps. Would be helpful if I could do this in VCrave, but if not an example in pure G Code would do.

Hi there.
I know this is months ago, but.
If it is any help you can cut, straight, convex and concave tapered holes with the software CAMBAM (97) and its free to download a trial that allows you to use it 40 times with no limits.
You select the hole you want to cut in the viewer and select profile operation. In the properties section of this operation you just created, set for inside profile, and then set the options for side profile shape (straight, convex, etc) and the angle in degrees (I think it is degrees). CAMBAM will then calculate the path based on the cutter details you have selected.29265

regards

Voicecoil
17-12-2020, 08:48 PM
Interesting, thanks for that. Does it allow you to do chamfers with an arbitrary angle around the edge of a part as well by any chance??

EddyCurrent
18-12-2020, 08:36 AM
Interesting, thanks for that. Does it allow you to do chamfers with an arbitrary angle around the edge of a part as well by any chance??

Yes.
Examples here show circles but any shape will do.
https://cambamcnc.com/doc/1.0/cam/side-profile.html

There's also a "Break Edges" plugin I use for chamfers but angle depends upon the V tool used.
http://www.atelier-des-fougeres.fr/Cambam/Aide/Plugins/Break_Edges.html

Another, but slower method, would be to create a 3D surface with required chamfers then use a 3D Machining Operation.

Voicecoil
18-12-2020, 03:44 PM
Cheers for that, I might buy Cambam then. I'd thought of the 3D route, but as you say, slower to machine (and draw up!) when the job's mostly profiling with a few angled edges.

Kitwn
19-12-2020, 10:29 AM
I like Cambam a lot, it's easy to master but powerful as well. It is greatly improved by the large selection of plug-ins available to extend it's capabilities and the support forum that backs them up. The trick is knowing where to find them...

http://www.atelier-des-fougeres.fr/Cambam/Aide/Plugins/plugin_menu.html