I used Mach3 in 3D raster carving extensively. I never noticed any error whatsoever in the "Simulate Toolpath" time estimate.
It should not be done in CAM software. That's just not possible. Now in the case of 2D cutting some plywood, changing machine acceleration will likely make <1% difference. Who cares, sure. I'm not that much of a perfectionist. BUT, in the case of 3D raster carving, the distance/feedrate calc might say 45 min yet the actual runtime is 2 hrs. Because acceleration becomes the deciding factor. There's no telling what it'll be like. Sometimes sharp surface textures which aren't even these deep, dramatic features really drag down the runtime. Also, blending and path tolerance will have considerable effect. That implementation is very specific to the machine and I doubt CAM software could reliably reproduce its effects. It's very important to have access to these figures. For example, in 3D carving, I discovered the machine almost never went faster than 150 ipm. It would go much faster with smoother surfaces, but it rarely occurred- what having a 300 ipm speed DID do was create some inconsistency in surface finish in those few smooth areas, with only a petty improvement in runtime. It wasn't worth it. I decided to go with 125 ipm and that only increased runtime by like 5% over 150 ipm, but with very consistent finish. Similarly, I had to make a call- my drive system is VERY effective. It is technically capable of fantastically high accelerations, but it will shake the machine all over the floor and could prematurely wear components. I can see what toning down the acceleration is doing to the 3D performance and make a decision. So now I need to understand the effects of path blending tolerance (G64 P0.001) in addition to accelerations. This is a per-design tradeoff, IMHO. If I start from "get this job runtime down to ~90 min", well, if increasing the path tolerance to 0.05 decreases runtime by 20%, I can decrease raster stepover by 20% which could result in a net INCREASE in quality. But I got no idea what effect G64 will have on runtime in the real world. And I have no way of finding out anything unless I actually run jobs over and over and time them. Considering I'd really need to get hundreds of datapoints to fully understand G64 path tolerance vs acceleration vs raster detail, that's just not ever going to do it. I could spend years of my life trying to understand the real-world effects if there's no accurate simulation of it. In fact, in Vectric Aspire, there's a Tolerance figure there- I already discovered that one. Similar to G64 path tolerance. It defaults to a very low value and increasing it can substantially decrease runtime. Danny On 4/23/2016 10:50 AM, Dave Cole wrote: > That is more usually a function of the Cam software that I am used to using. > > I don't know if Mach3 is all that reliable when it comes to accurate > numbers for run time. > I recall that being a problem actually in some situations. > > There is some discussion of that on the web. > https://www.machsupport.com/forum/index.php?topic=18557.0 > There are several other links available. > > Dave > > > On 4/23/2016 4:19 AM, Danny Miller wrote: >> As I've said before, I'm used to Mach3. In this case, Mach3 allowed me >> to click "Simulate Toolpath" and gave a 100% accurate figure for the >> file's runtime. It actually simulated with the same path that would >> execute the code, just without waiting to step anything out, so it takes >> into account the max speed & accelerations of the machine. It sometimes >> took a minute or 2 to evaluate large 3D files that took hours to run. >> >> This is super-important for tuning. I obsessed a lot about the best >> speeds & accelerations and it paid off. Also kept me from getting into >> trouble with a job that would have taken 8 hrs. >> >> I thought "Properties" would do that, but I was wrong. That just takes >> distance, divides by feedrate, and adds them up. This is not remotely >> valid for fine 3D carving, it requires so much acceleration that >> feedrate is almost irrelevant. And I'd like to see what effect path >> tolerance has. I'm not going to sit over the machine and run it with a >> stopwatch. I tweak these parameters often. >> >> Is there a way to do this? >> >> Danny >> >> ------------------------------------------------------------------------------ >> Find and fix application performance issues faster with Applications Manager >> Applications Manager provides deep performance insights into multiple tiers >> of >> your business applications. It resolves application problems quickly and >> reduces your MTTR. Get your free trial! >> https://ad.doubleclick.net/ddm/clk/302982198;130105516;z >> _______________________________________________ >> Emc-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ > Find and fix application performance issues faster with Applications Manager > Applications Manager provides deep performance insights into multiple tiers of > your business applications. It resolves application problems quickly and > reduces your MTTR. Get your free trial! > https://ad.doubleclick.net/ddm/clk/302982198;130105516;z > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. It resolves application problems quickly and reduces your MTTR. Get your free trial! https://ad.doubleclick.net/ddm/clk/302982198;130105516;z _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
