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regeneration of part with large pattern

tracy

New member
Ok, I have a sheetmetal part with a large (101x248) identical pattern of small rectangular extruded cuts that is mirrored across the longitudinal centerline. These rectangles have separately-modeled full radii which are reference patterned. I have made it a family table, because of concerns about regeneration times in assemblies. The generic has a 2x2 pattern on each side of the centerline, with a cosmetic sketch of the pattern area (simple rectangles), while the instance eventually needs to have the full 101x248 pattern. A similar part will end up having a 30 x 858 pattern, also mirrored.

I have not yet successfully regenerated this instance with the full pattern. I have had some success with smaller patterns.

I'm running Creo 2.0 M040 on a Dell T5400 with a Xeon E5405 2 GHz processor and 4 GB of RAM. It appears to be using all four cores, and less than 2 GB of memory.

I set this thing to regenerate the whole pattern over the weekend, and when I got back this morning, it appeared as if Creo had gotten lost in the weeds.

Would I be best off:

1) expanding the instance pattern little by little (say, do the 101, then add the 248 2 rows at a time), and saving between verifications,

2) suppressing the rounds until the rectangular pattern is successfully regenerated, saving, then regenerating with unsuppressed rounds,

3) combining options 1 and 2, or

4) should I just kill this and restart and hope that it doesn't go off into the weeds, again?

The part is essentially a screen, and I HAVE to regenerate this at least once, so that I can have a DXF and a drawing for the part manufacturer. The rectangles are patterned identically, not generally, and the radii are separate features that are reference patterned. I can't share the part file because of IP concerns.

For what it's worth, I've also tried to do this with the radii encompassed in the sketch for the cell, but that took way longer to regenerate a 10x10 pattern than doing it with the reference-patterned radii did.

Nothing else is running on the machine, except Creo, and Creo's CPU usage hovers around 26%.

Thanks,

Tracy
 
Very cool, and trying that out, but Creo seems to have gotten itself stuck at 4749 features remaining to regenerate. I'm going to try it again, but maybe just half the pattern size, at first.

Tracy

ETA: It does seem to have regenerated the first 20k or so features a whole lot faster.
 
Hello,

In the option tab you can choose identical instead of general.
But if you use identical, you can't go outside the boundary of your piece and create a half of pattern.
They al have to be identical.
This was the regeneration goes a lot quicker.
 

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Jacek,

I think that has some merit. I've tried the turbo pattern idea, but I'm running into two separate problems with that. One, I can't "solidify" an extruded cut (I've tried as many options in the solidify tool as I can see), and two, even with the turbo pattern, something funky is happening. It may be that it's still thinking, but I left it overnight, and it was no further along this morning than when I left last night. I think Creo is still going out in the weeds.

I've got another turbo pattern going now, so we'll see if it hangs this time. If it does, I think I'm going to try a 101x10 or something along those lines, then pattern that.

Tracy
 
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Hello,

In the option tab you can choose identical instead of general.
But if you use identical, you can't go outside the boundary of your piece and create a half of pattern.
They al have to be identical.
This was the regeneration goes a lot quicker.

Yes, I tried identical, but it still takes forever, and the program seems to wander off, after a while.

Tracy
 
I run into this same problem all the time. I've tried the surface copy method, it only works part of the time due to the complexity of the geometry in the pattern. The only thing that I've found that reliably speeds up the regeneration is a faster processor. When I went from a 2.0 Ghz to 4.2 Ghz, speeds were MUCH faster. Still takes 20 minutes to regen a 110 x 150 pattern, but it took hours with the 2.0
It also helps to have more memory. Even though it appears that you are not using it all, you are likely swapping to the hard drive frequently. Another thing that can help is to split the geometry into multiple parts and make patterns of each of those parts. It seems that a directional pattern is also faster than a reference pattern.
 
32 Bit windows will only use 2Gb of RAM per process max. Creo will not utilize more than a single processor. You can get up to 3Gb of ram per process using the /3GB switch in the boot.ini but this has a number of caveats with it and if you don't know what you are doing, will cause more problems than it solves.
 
I run into this same problem all the time. I've tried the surface copy method, it only works part of the time due to the complexity of the geometry in the pattern. The only thing that I've found that reliably speeds up the regeneration is a faster processor. When I went from a 2.0 Ghz to 4.2 Ghz, speeds were MUCH faster. Still takes 20 minutes to regen a 110 x 150 pattern, but it took hours with the 2.0
It also helps to have more memory. Even though it appears that you are not using it all, you are likely swapping to the hard drive frequently. Another thing that can help is to split the geometry into multiple parts and make patterns of each of those parts. It seems that a directional pattern is also faster than a reference pattern.

Well, if I could get a reliable run time out of it, it wouldn't be an issue, because I could let it regen overnight. The big hangup with that is that it seems to lose track of itself at some point in the regen cycle, which causes me to have to kill the process and restart Creo.

I haven't had any luck trying to do anything other than a reference pattern on something that WANTS a reference pattern. Perhaps there's some config option I'm missing to let me pattern other than reference when that's what it chooses, automatically.

I'm stuck with the processor and memory I have, right now. Looking at Resource Monitor, I've got 1463 MB cached out of a total 4093 MB installed with 120 MB free. There's about 143 MB paged memory.

I dunno. I guess I'll just have to keep slogging through it.

Tracy
 
32 Bit windows will only use 2Gb of RAM per process max. Creo will not utilize more than a single processor. You can get up to 3Gb of ram per process using the /3GB switch in the boot.ini but this has a number of caveats with it and if you don't know what you are doing, will cause more problems than it solves.

This is a 64-bit machine, running Windows 7 Pro x64, which I neglected to mention above, so I'm not sure memory utilization is an issue.

Tracy
 
regarding the solidify problems:

well, this issue is a part of "turbo Pattern" approach by default. I mean, I encounter it almost every time I must solve big patterns long regen time.

So, basicaly, If you create basic quilt of merged surfaces, then pattern the group of merged surfaces, mentioned Merge can fail.

Usually this is because of Normal direction of merged quilt. I solve this by switching the sequence of merged surfaces inside Merge tool.
 
Sounds like the perfect time to hit up your boss for that 3.6 GHz machine with 16Gb of RAM! :cool:

Wish that was an option. I'm a contractor working for a small start-up with a limited budget. I do have to replace my own computer at some time in the near future, and I'm going to max out processor and video when the time comes.

Tracy
 
I've never seen the inability to choose a directional pattern. Maybe it is related to which license you have?
 
I would try deleting your pattern, ungrouping the features, and then patterning each feature individually. I've found this to improve performance when it hangs.
 
regarding the solidify problems:

well, this issue is a part of "turbo Pattern" approach by default. I mean, I encounter it almost every time I must solve big patterns long regen time.

So, basicaly, If you create basic quilt of merged surfaces, then pattern the group of merged surfaces, mentioned Merge can fail.

Usually this is because of Normal direction of merged quilt. I solve this by switching the sequence of merged surfaces inside Merge tool.

Essentially, what I have is a thin piece of sheet metal, pierced with an exceedingly small rectangle with fully radiused ends. When I modeled this, I did it as an extruded rectangular cut, then added the radii as full rounds in one feature (as opposed to making each end a separate feature).

I selected the inside surfaces of the cut, copied and pasted, then tried to solidify that copy. It didn't work. I tried every option or combination of options that I could think of in the solidify, but it just won't solidify. It really doesn't make sense to "solidify" the lack of something, anyway.

If I pattern the copy, I get a really nice array of little ovals that I can't get to cut through the sheet.


I have a sneaking suspicion that my problem can't be easily solved. I wonder if making it a solid, rather than sheetmetal, would help, but I guess it probably wouldn't.

I think I will try your idea of making a pattern of a pattern, though, when I go back today. It can't hurt, and it might help. Luckily, I can use one machine to do that regeneration while I work on another on other parts of the project.

Tracy
 
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I used to work for CINCH Connectors near Chicago. There was one project that a different engineer was working on, where he was grouping a set of 6 or 7 features (cuts, drafts and rounds) and then trying to pattern it into approximately 30x30 pattern (900 socket holes) for an IC connector. Wildfire 2.0 was running overnight as well and still didn't complete the task by morning. I suggested he try to pattern a surface copy of the 7 feature group, then merge and then try CUT, USE QUILT. That worked better... to a degree. After repeated tries, we contacted PTC and one of our engineers went out there to visit, with the sample data. We discovered that we could easily accomplish the task in our 1 seat of SolidWorks in a matter of minutes. What gives???

PTC admitted that in Pro/E, when you pattern features and regenerate, Pro/E does a mass analysis upon every single featue that is successfully regenerated and writes it as an appendable file to disk, all the while, continuing to regenerate. This takes considerable resources and can/will bring Pro/E to it's knees. While SolidWorks only generates a single MP file at the END of ALL feature regeneration.

I left CINCH before I found out how they handled the issue, but even PTC folks had a hard time with this.

Bob
 

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