What is Smoothing Fusion 360 CAM? FF128

[@djberg3483]

Man John, after years of watching and many re referencing your fusion360 vids, I’ve ended up finally actually crossing paths with a cnc mill. This single video, is the most relevant vid to my personal needs to date! Making templates for the diaform I use to shape grinding wheels. So first scenario in cnc/cam airfoils lol, second laugh it’s on a 1989 series 2 interact 2… but at least I can drip feed it. Thanks for the years of learning tools, you n Lars Christiansen put into teaching the world all that you two have.

[@kaia8167]

I've been using smoothing for a while now without fully knowing if it was the best thing to do for my particular project needs. Not only am I now glad I've been using it all this time, but you also introduced me to a fantastic strategy for testing different smoothing/tolerance options (saving the stock and taking a look at the STL file) to see where my ideal tolerances are instead of just guessing. No doubt I'm going smaller than I actually need to, but now I don't have to guess! I know this video is a few years old, but I still wanted to say thanks :)

[@CatNolara]

FYI the double points come from the way Fusion generates the path. First the spline gets segmented into straight lines, then they are offset by half the tool diameter and on outer points an arc is added, that wraps around the point. The smoothing looks at all the lines and arc segments and replaces them with a few circular arcs.

[@bluustreak6578]

That's interesting :)

[@Shopbuilt]

It's to bad it isn't always on by default, I always forget to check it....

[@ScottMoyse]

You can turn it on by default for each toolpath in the Compare & Edit dialog... right click on the toolpath and select it. Find smoothing, right click on the smoothing setting and set it as Default Yes.

[@curryandapint]

I've posted my problem on the Fusion CAM forum but didn't get an answer. I've got part of a shape which is a slope. I'm using a flat-end mill and it make she slope look very 'stepped' (even though the machine head only goes down 1mm at a time. Is there a way (for example) to make a pyramid in CAM without visible lines for every level. I tried bull-nose tip and 'smoothing' but it doesn't make much difference.

[@danl.4743]

Nice demonstration with the machines at the end. Really drives the point home.

[@BiggestNizzy]

I run my tolerance using a formula. 1/3rd the stock left on Min 0.005mm Max 0.5mm it gives you really quick generation. when roughing. I tend to keep smoothing at 0.002mm

[@TobiasAnderer]

Thank you John. It helpt me a lot. I am working with an old deckel fp4, runns so mutch better now.

[@homeworkshopengineering]

Thanks for this John, I run an old interact 1 with Heidehain TNC 151 and drip feed programs. I am getting really jerky movements in adaptive so this explains it.

[@stefanberglund983]

Well, you may have to add "m90" after each line if you havent done it already. Otherwise the machine stops after each block. I changed the tnc155 postprocessor and my tnc155 mill runs great now! :)

[@homeworkshopengineering]

Stefan Berglund Thanks for the tip I will look into that

[@jacobacostamasterscribe2200]

If it’s an old machine, pay attention to the baud rate too

[@routercnc9517]

Great video John. A lot of work went into making that and it was well explained.

[@mryoutuser]

Nice Video Jhon, You may give NC Corrector a try for detailed g-code path info. Does HAAS machine support an SSS (Super smooth surface) feature that may eliminate that jerky motion? Thanks

[@occamssawzall3486]

mryoutuser G187 P3 E.001 would give a finish profile movement with a .001 arc tolerance smoothing factor.

[@TROYOSTRANDER]

so many tips in here. watch to end for an actual machine demo

[@spkrman15]

Awesome Video guys and girl. 😉. I really like that you took the time to show the impact it has on different machines. That was a good amount of work for 2 mins of a 12 minute video. I for one appreciate that kind of effort.

[@gerrykmack3296]

John- Another great video! I need to cut corresponding parts which have spline-type curves, and fit together perfectly. Will using identical tolerance & smoothing setups guarantee this? In my case, a perfect fit between the parts is more important than matching the CAD curve exactly... What is the best strategy to accomplish that?

[@sbirdranch]

Great explanation and +1 on the video edit. The timely onscreen text and graphics were great ~P

[@MotorsportsX]

This is why I like Hurco machines. I can throw a spline with THOUSANDS of points at it, no smoothing in the cam, and the Hurco gives me a highly accurate part with no jittering. If you have a haas, you also need to know how g187 works. if you smooth it to much in the code, and then youre running g187 p1 e.050, you are going to end up with an inaccurate surface.

[@OakwoodMachineWorks]

>Comparing a machine that easily costs 15-20x more than a tormach to a tormach.

[@RobLlewellyn1]

An utterly brilliant video. They all are I know. But this had details and cut aways to illustrate the topic. Frickin brilliant.

Another priceless one ! Thank you so much again John

[@jomme918]

what if smoothening tolerance is a good deal great then your general tolerance,,, 0.02 general and 0.5 smothening, ?

[@ScottMoyse]

Excellent video John

[@DCT_Aaron_Engineering]

Excellent explanation John. Thanks for taking the time to share this with all of us ;-)

[@mavericksdesign7033]

You have explained this so well John. Thanks

[@hillfortherstudios2757]

There's a free G Code Plotting app online!!!!!???? Thanks man!

[@kahansoni7558]

Isn't there a technique in which the machine is controlled by equation.??...i mean all the splines have their own equation so isn't it possible that we have to only put some variables of that equation and tool will follow the path rather than divide that spline into small line segments...??

[@TheWireEDM]

The mahine can only move in straight lines, so now the controller would have to do the smoothing. Far more efficient to do it prior in CAM, as you can see/test the results of different settings.

[@stevensimpson6208]

I wish I knew about this before my 22min gcode took two hours... thanks though!

[@MKA667]

This video is almost four years old now, and it only has 658 likes: how is that possible?

[@bob_mllr]

Great tutorial. Thanks John!

[@jamesdavis2027]

I assume that splines are equation driven curves at some level. I wonder if it would be possible to add a separate function in some future update to gcode architecture which calls a spline by simply defining the variables within its equation. The math is way above me, and I have a feeling that it would still require an advanced cnc controller, but it would provide the most accurate results.

[@gredangeo]

Fanuc Series 18i already has Spline Interpolation actually, and that controller is at least older than 2005. The question is how to get the Post Processor to figure out exactly what it's looking at, and understand that the implied motion of segment of points can be redefined as a Spline command.

[@occamssawzall3486]

Regardless of the coding, the machine still only moves in linear directions. The “spline codes” are basically a simple way to manually define a splines path with points, and it combines controller side arc smoothing. Same as turning smoothing on in CAM, cept it’s all done in the background within the controller.

[@finnna8352]

Very interesting, thanks John! Great job of explaining it.

[@juanandrescarri27]

Fantastic

[@johnswilley6764]

Thank you for your great explanation, I really a precise it. Very explicit and concise.

[@BerndFelsche]

Interesting video. Don't know if Tormach simply haven't implemented it but the core LinuxCNC (now) "supports" G5[.x] splines www.linuxcnc.org/docs/2.6/html/gcode/gcode.html#sec:G5-Cubic-Spline Back in the "dark ages" (1982 :-) ) I wrote a research paper on (C)NC machines and one of the holy grails was constant velocity machining throughout a complex motion. While there's about a million times as much processing power available within current CNC machines, the "tool chain" from CAD to the cutting edge has still not caught up. I suspect that it's in part because it's very hard to decide where the smoothing is to happen; within the machine tool controller, the post processor or the CAM modeller. While it's most attractive to put e.g. spline emulation into the post-processor so that the CAM modeller is always dealing with virtually the same machine; regardless of actual machine (within operating envelopes, obviously). OTOH a machine controller running LinuxCNC or similar can offload post-processing *and* the same CNC (G-code) program can be loaded onto different machines as long as their controller can hack the job. An ideal CAM would accept any CAD model of a product and, without human intervention, be able to produce "G-code" for the machines necessary to make the part, along with a specification of stock (from a "library" of available sizes) and fixtures necessary. Obviously it needs a "dictionary" of available machines and tooling; and for comparison purposes, the relative costing of all the combinations.

[@occamssawzall3486]

Bernd Felsche The G5 spline is more for coding size and ease if you’re manually programming, rather than machine movement. Machines are still stuck using a combination of 3 linear directions at varying feed rates. Smoothing in the CAM and G5 spline on the code side are pretty much identical in taking a spline path of hundreds of points and reducing them down to a combination of lines and arcs with fewer point to point movements. On a G5 the controller is still processing a series of lines are arcs in the background, you just don’t see those movements in the code is all. It’s similar to a G187 P# E# on HAAS machines in which it will override the coded positions and delete or add points to maintain the specific arc tolerance set by the E value on the G187 line. The DMU I run has a similar code line that not only does arc tolerance point reductions, but also overrides the coded feedrate to maintain a constant velocity, so it doesn’t whip around tight corners even when it’s linear feedrate is over 200ipm

[@BerndFelsche]

It's ultimately up to the CNC machine to control tool position, velocity, acceleration and sometimes jerk by the combination of available servo controls and feedbacks. The machine knows the internal resolutions. The internal spline/NURBS following can be much more finely resolved than what one would sensibly generate from CAM. The controlled position/velocity can be more finely resolved than is worth programming as line segments. Internal curved motion interpolation can produce a more CAD-conforming shape than "segmentation". While internal "segments" are calculated, they can be within a tighter envelope. Block processing of equivalent segments can substantially slow machining, resulting in worse finish and frustrate e.g. internal look-aheads. (see www.fanucamerica.com/home/products-services/cnc/cnc-technology/high-precision-machining) IIRC, the Fusion360 CAM processor produces arc as well as linear segments to approximate a non-circular curve.

[@danielrose1392]

​@@occamssawzall3486 To stick with your argument, yes you are stuck to varying feed rates of your 3 axis, but you have the same problem with arches. Still circles are often not split up into individual line segments, especially when it comes to larger machines which have some momentum. Same could be done for splines, there is no need to have lines or arches as an intermediate format. The controller could directly evaluate the splines and translate it to feed rates. There are historically good reasons not to do this, the computational power, but this argument is no longer valid for at least 10 years.

[@klavsvasilis]

OHHHHHHHHH I thought i got some problems with motors, turns out , i got problem because i use splines :D

[@klavsvasilis]

And I was googling vibration... instead of jerking.. :"D

[@TheFixxxer11]

thanks

[@mikeberlinquette9896]

Great video ........You are smooooooth

[@dantahoua]

You make my day!

[@Ja-ug5gu]

Can’t say thank you enough

[@jomme918]

by the way, good www job your doing for all of us.

[@GiovanniCarloIglina]

So a Tormach and a Haas don't really have lookahead and handle segments really badly and a simple Arduino Mega 3D printer board with Marlin software has it and run segments smoothly? Spooky...

[@TheWireEDM]

They all have it, but there are more variables at play here. On a Heidenhain controller it is easy to spot from the parameters list, but in essence it boils down to to the speed at which the machine gets the code (drip-feed vs. HDD/SSD), lookahead buffer size, wanted feedrate (as in does the machine move faster than it can read&process code in to the lookahead buffer), the parameters of the machine itself, like how tightly it tries to follow the given path, how much jerk is permitted and so on. That Marlin will smother to bits if you try high feedrates with 0.001 mm max path error, which is quite typical of a CNC milling machine. And the drip-feed issue comes in real fast, plus the was it 18 block lookahead buffer which is filled to the brim by just starting a spline.

[@shansultan1995]

Hello Sir Sir I am a Pakistani and me also see your video but I am start business CAD CAM so please sir I need complete Course fusion 360 programming a🙏🙏🙏🙏🙏🙏

[@maercnc6707]

Great.!!!

[@mikiauto73]

This is not Fusion 360