Do you ever lie to Vcarve?

This forum is for users to post tips and tricks they have found useful while working with VCarve Pro
Post Reply
johnelle
Posts: 45
Joined: Thu May 25, 2017 7:23 pm
Model of CNC Machine: Shapeoko 3
Location: Groton MA, USA

Do you ever lie to Vcarve?

Post by johnelle »

I am turning out a bunch of small pieces and have found matching the tooling with what I want to do a real challenge. One of the things that really peeved me was when Vcarve grayed out a tool that I was pretty sure would work fine.

As I was reaching a hypnotic state watching the carving bit go over and over some details, an evil thought popped into my head. I wonder if folks routinely let the software do its CAM thing with a certain tool defined but then actually load a different tool. For example telling it you are using a sharp engraving bit but then actually loading a small ball nose instead.

I would experiment with it but I am in the middle of production.

So is this just common practice amongst the seasoned CNC'rs or is it just an evil thought that I should drop?

Bob Reda
Vectric Wizard
Posts: 858
Joined: Wed Aug 16, 2006 7:34 pm
Model of CNC Machine: shopbot 48x48 upgraded prt
Location: Monessen, Pa
Contact:

Re: Do you ever lie to Vcarve?

Post by Bob Reda »

I do it, also if you use the keyhole gadget you will lie telling it is an endmill when you are using a keyhole bit.
Bob

4DThinker
Vectric Wizard
Posts: 1701
Joined: Sun Sep 23, 2012 12:14 pm
Model of CNC Machine: CNC Shark Pro, Probotix Meteor 25" x 50"

Re: Do you ever lie to Vcarve?

Post by 4DThinker »

You have to "lie" when using any router bit that does an undercut, as vectrics' products can't preview what the real result of their use will look like. T-slot cutters and Dovetail bits usually. Occasionally a big ball end on a small shank. I also am fibbing to the software when I create toolpaths for what looks like a normal flat rectangle of wood but is actually the end of a chair or table stretcher clamped at a compound angle under my CNC. I'm guessing this isn't what most folks do with their CNCs, but it is a fairly common occurrence in the fine furniture workshop at the university I teach at.

4D

User avatar
IslaWW
Vectric Wizard
Posts: 1402
Joined: Wed Nov 21, 2007 11:42 pm
Model of CNC Machine: CNC Controller Upgrades
Location: Bergland, MI, USA

Re: Do you ever lie to Vcarve?

Post by IslaWW »

"Do you ever lie to VCarve?"

Of course, it's software. Software is made to be tricked, hardware is made to be modified. Not the other way around.
Gary Campbell
GCnC Control
ATC & Servo Controller Controller Upgrades
GCnC411 (at) gmail.com

User avatar
Leo
Vectric Wizard
Posts: 4082
Joined: Sat Jul 14, 2007 3:02 am
Model of CNC Machine: 1300 x 1300 x 254 Chinese Made
Location: East Freetown, Ma.
Contact:

Re: Do you ever lie to Vcarve?

Post by Leo »

I don't really think of it as lying.

Using the tool within it's capabilities to gain a desired result, is more appropriate.

Really, all a CNC program is even doing it describing a path from one point in space to another point in space. Everything else is just getting dragged along for the ride.

Tool shapes, no matter what the shape is - is really just going along for the ride.

Now - "GRAPHICALLY" - we "want" to see something else and Vectric draws in all the graphical stuff so we can more easily "see" what we want to see. They do a GREAT job at it, but there are limitations.

Soo - given the limitations - we can improvise a little to get the toolpath, but also understand the limitations but also "see" with our minds eye - what we want to achieve.

WHEW - I dunno if anybody actually read that, but me thinks, maybe it's bed time for me.
Imagine the Possibilities of a Creative mind, combined with the functionality of CNC

User avatar
scottp55
Vectric Wizard
Posts: 4713
Joined: Thu May 09, 2013 11:30 am
Model of CNC Machine: ShopbotDesktop 5.5"Z/spindle/VCP11.5
Location: Kennebunkport, Maine, US

Re: Do you ever lie to Vcarve?

Post by scottp55 »

I lie about the angle and flat on engraving bits all the time to get the effect I want if needed.
Does take a little playing around, as the preview will be wrong of course, and you have to actually cut, to see what you've got.
Play with small projects before production.
In buttons pic...it was the same exact toolpath and and 60 degree bit with .02" flat, but I changed to 30 degree on top row, and then fussed with tip width until I got what I wanted.
On burnt Maple pics , you can see I wanted more white area for contrast, so called the 60 a 30 degree, and you can see how on the right side it narrowed down the surface too much.
Takes a bit of playing, to get an idea of how it will actually cut.
When I used Cut3D, I made up imaginary TINY ballnose bits with tip size that matched engraving bit flat because it wouldn't let me use an engraving bit, and used 30 degree engraving bits for Tiny stuff, but not the other way around.
scott
Attachments
3 TOOLPATHS SAME BIT LYING ANGLE AND FLAT.jpg
LYING ABOUT THE ANGLE ON ENGRAVING BIT.jpg
LYING ABOUT THE ANGLE ON ENGRAVING BIT2.jpg
I've learned my lesson well. You can't please everyone,so you have to please yourself
R.N.

User avatar
IslaWW
Vectric Wizard
Posts: 1402
Joined: Wed Nov 21, 2007 11:42 pm
Model of CNC Machine: CNC Controller Upgrades
Location: Bergland, MI, USA

Re: Do you ever lie to Vcarve?

Post by IslaWW »

Listen to Leo: "Tool shapes, no matter what the shape is - is really just going along for the ride."

Truer words were never spoken. We get caught up in the pseudo details of how to do all these toolpaths by the numbers, tool descriptions, form tools ad infinitem. I like to see what action a particular type of toolpath delivers. Of course the 2.5D are my favorites as they can do so many things. The VCarve toolpath has a fairly rigid set of rules, but the others.. no limits!

Learn to look over and understand the wireframe toolpath view and you will learn a lot. You will see what the center bottom of the bit does, that how they are calculated. You can use that info along with some basic knowledge about bit shapes in material to expand your horizons. Personally, I do not use the toolpath preview for my daily work. In fact, if I didn't use it to prep training slides I would never have had a need for it. I learned on the wireframe and use it still today. Especially for rotary. I also realize this is not typical.
Gary Campbell
GCnC Control
ATC & Servo Controller Controller Upgrades
GCnC411 (at) gmail.com

Fleming
Vectric Wizard
Posts: 400
Joined: Tue Oct 28, 2008 3:41 pm

Re: Do you ever lie to Vcarve?

Post by Fleming »

I lie quite often when using V bits to do text, especially small text in wood that tends to splinter out. I spec a 60 degree bit and then cut with a 30 degree bit. This leaves the boundaries between letters a little larger and the letters such as an "o" a little fatter within thus getting a cleaner cut. What you sacrifice is the sharpness of corners but for small text your eyes don't typically see that.

Post Reply