3D Toolpaths- Which ones are best and best used for what?

So trying to learn whats best without tons of hours in testing and trial mostly error.

I have BCCv24 Pro. So it has these paths to choose from,

Z Level Rough
Z Level Finish
Slice Planar
Slice Spiral
Slice Radial
Plunge Rough
Advanced Rough
Flatlands
Equidistant Offset
Pencil

I am sure some of those are better depending on the material and geometry we are cutting but what should be my staple path for stuff like filleted aluminum? I assume the Pro paths are best since they are the upgrades? Some ideas for me to go off of would be cool. Complete newb here on 3D pathing.


Thanks!

that's a pretty wide guess for us -- stuff like filleted aluminum.

A drawing at least would help.

Zip a drawing and post if you can

You got us with both hands tied behind our back.
That is like setting us up on a blind date,most likely won't end well.
Please a .bbcd file.

If you are going to be doing a lot of 3D tool paths..BoB has made great advancements since 24,,just saying.





"Fillett Aluminum" is that made out of Billett ? sorry,could not resist

but she's really really pretty

LOL, knew it would be kinda broad LOL.

Give me a min, will get a file.

Probably the most used (If you have Pro and by me anyway) would be the "Advanced Rough" for roughing out/semi rough/semi-semi rough etc and "Equadistant Offset" for finishing.

There are of course instances where a particular job may well be better run with different strategies but I would say the above are a fair starting point, will do most jobs :D :D :D

Regards
Rob
:rainfro: :rainfro: :rainfro:

Here is an example.

Can someone tell me what I am doing wrong on the second pass? It wont compute only locks up BCC and makes it crash after about 10 minutes of computing. 1st rough pass with 1/2" bit runs fine.

I don't know about your specific projects, but if you're asking what a person most likely uses as their go-to 3d strategies over a year's time, I'd have to agree with Rob. I'd say they are in this order:

1: Advanced Rough (use on almost every 3d project)

2: Equidistant Offset - Produces the best finish on difficult surfaces, but I do wish that it had a way to avoid dwells due to hard changes of direction (like a loop around instead of a chevron motion). Still one of the best for most jobs.

3: Planar Slice - If you can cut is in a line on one axis, this is the best option. You may have to step over tighter than you'd like if the surface goes more vertical than 45degrees, but so long as you set up the toolpath based on the worse case step over in the steep areas, you'll get a great finish. The "adaptive" version of this in V27 completely eliminates all the issues with Planar Slice and steep walls, plus you can add a loop around at the end of each path to link them more smoothly. When I get V27, this will eat into the operations I do with Equidistant offset a bit.

4: Flatlands - Used on a lot of projects, but not super critical because you can do the same thing in 2d with a little effort.

After those, I don't use a lot of the 3d toolpaths very regularly. I still use more 2d toolpaths and drilling ops than 3d toolpaths on a day to day basis.

Quote:

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Originally Posted by Beansdiesel

Here is an example.

Can someone tell me what I am doing wrong on the second pass? It wont compute only locks up BCC and makes it crash after about 10 minutes of computing. 1st rough pass with 1/2" bit runs fine.

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First thing is that you're going to want to set up your stock. That's really one of the only draw backs to V24 is that the stock wizard is a bit light on features. Starting in V25, you could be much more specific about your stock, and how the stock relates to the origin of the part for each machine setup.

The second thing I notice is that the boundary you created has some problems with gaps/overlapping geometry, so you'll need to clean that up for it to be useful. Whether you are using it as a boundary in the toolpaths later or not, you can also use it to define the stock geometry. You'll want to delete the points, then zoom in and delete all the little tiny line segments (there is one or two at each interior corner. It's also delete the lines going from the inner corner out to the radiuses above the wing looking platforms. Once you have all those deleted, just the "Line > Join" to join the ends of the remaining geometry. If you do it right, you can hold shift down and click on any of the lines of the boundary with the selection tool, and the entire boundary will all be selected as a chain. Once you get to that point, you can right click on "Stock Geometry" in your cam tree under the milling operation, and the choose "reselect". Go to the boundary, shift click on the boundary so that it all highlights, then right click and choose "OK". This will create stock geometry that is the same shape as your boundary. If you need to change the height of the stock, right click on "Milling Stock" in the cam tree and choose "Edit" from the drop down menu. This will allow you to specify the stock thickness (among other things).

Once you get to that point, try to calculate the toolpaths again. When I opened the file, the toolpaths had been "blanked". If you don't know how to blank/unblank the toolpaths, let us know and we can help you with that. When I ran the calculations, the system took much longer to generate the second toolpath as you created it, so it does take some time and you may have to be patient. If you're computer is a little slow or you don't have a great graphics card, it might take as much as 10 or 15 minutes. My computer is pretty speedy, but it still took 1 minute and 15 seconds to process the second operation while the first one only to 14 seconds. That might help give you some idea how long you may have to wait. If your computer takes 45 seconds for the first operation, you could expect close to 5 minutes for the second. Often Bobcad seems like it has crashed, but really it just needs some time to itself.

Ahh ok, I thought I had got that boundary cleaned up, guess I didnt. Not sure why I had them blanked but ya I know how to blank and unblank them.

Did your computer run the second path as it was or did you fix the boundary first? Mine refuses to run it. Just changed the graphic card to something better and didnt help any. Will see if it helps out with crashing though.

It ran it without changes to your geometry, but it did take much longer to process.

Another thing is that once you do redo the boundary, you'll have to remember to reselect it for the second operation. I would also recommend that you create a surface that covers the large holes in the middle of the top. Those holes aren't being ignored like they should be and are probably one of the sources of problems. I created a 4x4 square centered around the origin, reselected it as the stock (you have to "clear selection" in the "All" drop down first, then reselect) and set the stock height to 1.4". This increased the calc time for the first op to approx. 18 seconds. Once I created a surface over the holes, the calculation for the second op dropped to about 17 seconds for a total of 35 seconds to calc both ops, so it clearly made a difference.

If you are in 64 bit Windows, you should also open your task manager and monitor the memory usage. In my case, I'm finding that V24 will just simply run out of memory after a while, so you should save your files often, then when you start to run at about 3.5gb of memory usage, close and re-open Bobcad. It wasn't really designed for 64 bit systems, and I think that it's not clearing the memory well for some reason and 32 bit apps are limited to about 3.7gb it seems. I'm not knowledgeable about the technical stuff behind that, but closing Bobcad and reopening it will keep you running much smoother if you see the memory getting up there and will be worth doing. I think the rapid consumption of memory in your case may also have to do with the bad geometry, the holes that don't get recognized but shouldn't be part of the op, and the lack of stock definition causing the calculations to be exponentially larger than they should be. Once I fixed those issues, I'm not seeing the memory escalating and I can recalc a dozen times without getting anywhere near the max. With the two ops as I redid them, I get about 200mb of memory used up each time I recalc, so eventually you'd get to the max, but you can work for quite a while before you would. I've attached an updated version with some modifications so you can look at them.

Another thing I meant to address is that the toolpath strategy takes the stock into account when it generates the toolpath. Not having the stock defined is like leaving a variable out of the equation, which likely is one of the calculation issues you're having. The very first thing you should do when you start doing CAM operations is define the stock. As you can see in the two images I posted, the toolpath changes to reflect the stock, so you can imagine that if there is no stock, it's hard for Bobcad to guess what you meant to do.

Thanks mmoe, trying some your suggestions out. Good to know on the stock geo, wasnt sure if 3d paths needed it or not. Thought I had put a stock geo on one of those square lines, not sure if I didnt or I deleted it at some point messing with everything. I will make sure and always have it from now on.

On that boundary on the second pass, I cant for the life of me make the ends connect. I have tried everything I know, connect lines, intersect points, end points, clean up utility etc. My way of checking for gaps is to use select and hold shift and click on it, if its broken it wont all light up. The way I made the line was to use the line offset and offset it .250 outside of the original that I had extracted from the solid. When I do that it leaves gaps at the inside curves. Then nothing I try that normally works will reconnect them.

It's not just if the geometry is broken, it's also if there is an extra piece of geometry. My guess is that you missed deleting one of the little line segments. I'll make a quick video to show what I'd do.

Here's a link to the video. I made it as short as I could to keep the file size down, but it's still a 30mb download. Hopefully you're not on dial up or something (do they still have that?).

I didn't zoom in as much as I maybe should have for the deleting of the lines, so I'll just tell you that there are two lines and a point in each corner that I deleted. You should delete one long line, one very short line segment (which didn't always show up as well in the video) and one point in each area you see me delete things. The points are hard to say if they are exactly on the ends of the other lines, so I feel it's best to delete them in this case. Then you just use the "Join" line and put the cursor near the end of the line where you want to snap to/from until the line you want to intersect with is highlighted red.

I didn't go through the entire toolpath setup, so the second operation did take a little longer than when I went through it fully for the file I posted earlier. In this case, the second op took maybe twice as long to calculate as the first op, but that's just a matter of settings in the op that could streamline it further. The main thing is that I feel the safest way to set up the last page is with the S-links and retracting as I show. Just my opinion, but I do it that way pretty much every time with Advanced Roughing and never have collisions.

You should also check that you have the latest update of V24. It should be build number 546. I'm guessing you do or you probably couldn't open the file I posted, but worth checking. V24 if very stable for me, and I just don't get much crashing. I upgraded to V26 mostly for the increased productivity in how it's set up and also the additional "adaptive" toolpaths that really make Advanced Rough shine even more. Plus, I really like all the lead in options in V26 for the 2d toolpaths, which are vastly improved over V24 and V25. Stability of the program has never really been something that I've been concerned with. Keep in mind that I was running video capture software while the calcs were being made, which really saps some of the life out of your computer. As you will see, it still performed quite well and that's about the worst case scenario (next to rendering a 2 hour full HD video in Sony Vegas while working in Bobcad, which I have done at times!).

https://files.secureserver.net/0sw0RDIbYaPgcD


Another quick note. I like to use the extrude curves function even is I just need a surface. I find it faster than the surface tools in Bobcad to just make the whole solid, unstitch it into surfaces and then delete all but the surface I need. May just be me, but I always have trouble with the surface tools and half the time I end up doing it two or three times if I use them. The extrude curves function always works right for me the first time, so much easier IMHO.

Quote:

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Originally Posted by mmoe

I'll make a quick video to show what I'd do.

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Aha... Beat you!!!

bbcd cleanup - YouTube

In the video:

Cleanup boundry = quick trim end, translate arcs only to endpoints and rejoin. Stitch surfaces to solid.

At the end, I open a file with second op calculated. Didn't record the 2 minutes it took to calc... As mmoe states, it takes long because it is a "HEAVY CALC"... Just look at it and all the little ramps going forever... You could certainly do better on that path....

Machine association with his file seems to be corrupted....

Beans new an has a thread with "issues"... Here's my take on it....

He's stated it's a system purchased and new to them. They are probably fairly proficient in several softwares and other packages (Dad and vetric) Bean can somewhat fly around pretty well on computer...

V24 loaded and "dove into, full speed ahead".....

BobCad being slightly heavier than single objective packages (And especially 3 versions ago), needs definite structure and movement.....

Before going too deep with "how to do advanced rough", I would suggest a look into making sure the system is setup correctly, and a good post processor......

So, A good machine file. a good post processor. Pref's setup. A quick run through on how to use the system.....

my 2 cents...

(Damn mmoe... Beat me while I was typing.... :eek:)

Quote:

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Originally Posted by BurrMan

Aha... Beat you!!!



(Damn mmoe... Beat me while I was typing.... :eek:)

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I skipped Youtube, which saves time waiting for it to endlessly process the video. ;)

It is interesting that you were able to rough out those big holes. Did just stitching it to a solid allow that to work out? Without the stitching, I was just getting non-sense in those areas.

Another thing to try is setting your second Advanced Rough op to "Rest Roughing". I think you will find that it really isn't a necessary op as most of the cutting is just cutting air after the first pass. The main thing to remember is that Advanced Rough is just for quick material removal. It seems like you're trying to use it for some of the finish work, when really it just isn't the right op for that purpose. Once you get the roughing done, you'd want to move on to profiling and facing the surfaces using other strategies. I'll have another look tonight, if Burr doesn't do so first, and go through the steps I'd take to actually program a part like that. If I did the second Advanced Roughing, I'd just do it with the "Rest Roughing" on to save time. It literally only has to clean up the interior corners around those wing like things, which would probably save half an hour of machining. Everything after that is meant to produce a finished surface, so it's different ops.

"So, A good machine file. a good post processor. Pref's setup. A quick run through on how to use the system.....

my 2 cents..."

Burr,good summary.
I will add,if you are going to be doing parts like this often,and you like Bobcad (especially because of cost ) I would seriously upgrade to V27.The difference is tremendous.Bag 24 the sooner the better.Again,I am only saying this going off what type of work you are posting.

Thanks guys for the tremendous help. Seems as though my internet is down at the house so cant watch the vids till tomorrow. Before I left the shop I redid the boundary, my step overs and made it rest rough and worked perfect. Will try and clean it the rest of the way with equidistant?

This biz I bought was supposed to come with 2 weeks training from the previous owner/machinist. He has gone awol so far so I am stuck just trying to do everything I can on my own to get production going asap.

I am starting to get my head wrapped around BCC, may wind up just upgrading it to 27, will save me quite a bit of doe.