topic Re: Point to point move not accurate. in Fusion Support Forum

Point to point move not accurate.

davidturnswood — Sat, 17 Feb 2024 19:57:29 GMT

Hi,

I'm having an issue moving an object from one point to another. Selecting a target point in the center of the bottom of a cylinder and moving the object from that point to a point on the corner of a cube 200mm or so away. The issue is once I check the location of the point that it arrives at, the center of the bottom of the cylinder is about 4mm off in the y axis. ( -4.768E-06 mm ) It should show (0). The cube's corner has not changed, and it is still in the right spot. Y - (0)

The same error occurs with a point to point or point to coordinate move. I have to say, while not especially intuitive, I am a big fan of Fusion360's toolpath planning - especially for straightforward CNC 3 axis machining. On the other hand, moving from one position to another accurately is about the most basic operation I could ask for in cartesian space.

Can anyone suggest why Fusion won't make this move accurately?

Thanks,

David

Re: Point to point move not accurate.

g-andresen — Sat, 17 Feb 2024 20:13:13 GMT

Hi,

According to the motto "A picture is worth a thousand words", please show and explain what it is about and share the file.

Günther

Re: Point to point move not accurate.

davebYYPCU — Sat, 17 Feb 2024 20:22:43 GMT

That is.not -4 mm

it is -000004768 mm.

Might help…..

Re: Point to point move not accurate.

TheCADWhisperer — Sat, 17 Feb 2024 23:48:53 GMT

@davidturnswood

Are you familiar with scientific notation?

What measuring instrument will you use in the real world to measure to E-06 resolution?

Will your CNC reproduce that resolution?

Re: Point to point move not accurate.

davidturnswood — Tue, 20 Feb 2024 18:52:05 GMT

It's helpful to know that this is a very small number, but I am still unsure as to why fusion doesn't move the part to "0" when the point I have created is at "0". All I can say is Rhino 3D runs circles around Fusion when it comes to making drawings and getting things done efficiently. If I ask to move a part from any location to a specific point - it will move it there. This was bothering me enough that I moved a large number of models in rhino and re-copied them into the file I was working on. Thanks for all those offering assistance - any number that has an E in it is abstract to me considering I never had any high level math classes.

Re: Point to point move not accurate.

g-andresen — Tue, 20 Feb 2024 19:08:56 GMT

Hi,

please share the f3d file for reply

günther

Re: Point to point move not accurate.

TheCADWhisperer — Tue, 20 Feb 2024 21:15:04 GMT

@davidturnswood

I have never had any trouble getting any geometry dead on 0,0,0 in Fusion - so I suspect there is something else going on.

Do as @g-andresen suggested and Attach an example file. Based on experience here, I have a good idea what the true issue is.

Re: Point to point move not accurate.

davidturnswood — Wed, 21 Feb 2024 00:49:12 GMT

I would attach something but am way past that point and tore all of that up to start over. What did you think might have happened? I'll try it again some time and let you guys know if I get a differnent result. A separate issue I am having is: It seems hard to get fusion to generate arc movements. Trying to make my CNC turning output (grbl turning) run smoother on my machine. Arcs seem like a nice way to do that (at least I'd like to try using them). I'd love a tolerance setting that would effectively force Fusion to interpolate arc moves for an entire toolpath - down to a single arc attempting to describe something complex, all the way up to a very long complex squiggly line with hundreds of arcs in it. Any tips on generating arc moves in grbl-turn? I'm using adaptive toolpaths and profile finishing. Have played w the tolerance settings a bit (there are no smoothing settings).

Thanks!