Working with large assemblies

Hi

We are having problems with our large assemblies. A typical machine is
5000+ (not unique) parts with lots of subass. Our largest machine is
20.000+ (not unique) parts. This has never been loaded with all parts.
I think our pc's are ok, Dell Precision 360, 3 Ghz and 2 gig ram and
FX 500. Sw 2004.

They way we work is like this; no in-context parts, except from one,
our dummy part which is first part of all our assemblies. This part is
used for position parts in sub- assemblies. We found this is the only
way we can make top level assemblies. Except from very few parts we do
not use configurations. No red mates. Fully defined sketches. And all
parts are fully defines. I know that means we sometimes have a mate to
much but I have to often that parts are not mated when you think they
are. Not any equations. Basically as simple as possible. I have looked
at Matt Lombards homepage, thanks Matt, to get the settings right. So
I think we do things the best way.

But know we get messages like "SolidWorks cannot obtain enough memory"
more and more often. When we open drawings sometimes a view or two is
missing. Stuff like that. So we have talked about getting a new
expensive pc with newest hardware. That might help us but I think we
soon will get the problems back.

So I have been thinking. How do you guys with large assemblies work.
Do you make simple parts of every part and simple assembly
configurations? Make configurations of assemblies were all mates are
suppressed and the fix the parts. Or are there other things you can
do?

Kind regards and have a nice weekend

Klaus

 

Klaus,

You are on the right track, but you are reaching the limits of SW. I'll
share a couple more things with you.

1. Is the 3Gb switch enabled? When you get the memory errors what does
task manager say you are using? 1.6Gb or 2.6Gb? If it tells you the
former then the 3Gb switch will help with that problem.

2. At SWW the number 1 thing that was presented by SW was upgrading
hardware. You can probably get another 30 to 50% improvement by moving
to the very highest end AMD machine. AMD64 FX55, NVidia FX3000 or
better, Fast RAM and lots of it all on a good quality motherboard. See
www.tomshardware.com for a system that will be very fast.

3. Also from SWW they suggested creating simplified configurations of
parts for large assembly work. Have configurations without fillets and
other non-essential features for your large assemblies and drawings.
Whether this is time effective to create all these extra configurations
makes sense is something you will have to determine.

 

My two cents worth:
We made great gains in perfomance when changed just the video card.
We were using Matrox Parheilia 128 cards and switched to Nvidia Quadro
FX100 128 and It makes a huge improvement especially where we have cast
parts with many fillets shown. All other hardware was the same. Also,
we use Western Digital SATA (WD-740 Raptor 10k RPM HDD 4.5ms Access
time) to obtain (2x) improvement for file open speeds over the SATA
(WD-800 7200 RPM HDD). BTW, we only work with 500 to 1500 parts in
assys.

 

Your PC's are not ok. I have a Dell 360 on my desk now and wish I
could throw it out the window. I have a FX2000 with 1 GB of RAM and I
hate this box. I don't know if it's the mobo and the way it channels
the memory or what but this is the slowest box I have ever been on.
I've stripped down every service and it just blows. I can't wait to
get rid of it.

KM

 

Hi

Thanks for the response.
No, we have not tried the 3 Gb switch yet. My manager wants some kind
of proof that it works before buying. But I have considering trying
even though we only 2Gb Ram. The way I understood the articles on the
subject I will also gain some performance with 2Gb.

Hopefully we will get better performance with new hardware. But I was
curious to hear if someone is working with simple parts configurations
and other methods. I am sure that performance will be better. But I
also see a lot of problems. Problems with wrong configurations on
drawings. And with automatic printing and a colleague to fold (hope
right word) drawings I fear what will end up in the machine shop. I
also see a lot of time maintaining drawings and assemblies.

I have heard about companies building very large machinery in
SolidWorks and hoped someone from one of those companies would tell a
little about how they have solved the problems they have faced.

Kind regards

Klaus

 

The 3Gb switch is free and is well documented on this newgroup. It is
simply a setting in your boot.ini file that allows the operating system
to use more than 2Gb for application software. This seems to be your
problem. If you implement it then you may still find that your hard
drive thrashes when a very large assembly is loaded. Then you will need
to get more physical ram. But frequently the 3Gb switch helps those
with only 2Gb of installed ram.

This concern was brought up in the session at SWW. I really don't know
of anyone that uses this method in practice. It is something that came
out of SW testing to get better performance. It works but it may not be
practical for the reasons you mention.

 

Hi

Reading about the \3GB switch I came across this link:
http://support.microsoft.com/kb/108393/EN-US/

It describes how you limit how much RAM XP may use. This I can
understand. The 3Gb code I do not understand. What does it mean if you
write SOS at the end? Reading WT's part 3; there are four entries, do
you have four boot.ini files? Or how does XP know which to use.

Is the result not the same whether you use the MAXMEN or 3GB switch?

Best regards

Klaus

 

The SOS at the end is not necessary and has nothing to so with the 3Gb
setting. What it does is let you see some of what's happening when things
load, but it goes by so fast that I'm not sure how useful it is.

As far as the 4 entries, there is only one boot.ini file and all those
entries are in it. I would suggest that you run the two lines under
[operating systems] as that gives you the option to load the system with the
3GB switch by default, and also have the option to not load it if there is a
problem. I have listed the boot.ini as I would suggest, but you would have
to make sure that you compare everything to your existing file in case there
are other differences.

The NoExecute at the end is from XP SP2 saying that random programs can't
run by themselves.

As far as how you set the default load, in the System startup area there is
a box that lets you choose the default load, and you can also set the amount
of wait time before it automatically takes it. I have mine set to 5 seconds
as I figure that if I want something other than the default, I'm going to be
waiting there for it.

[boot loader]
timeout=5
default=multi(0)disk(0)rdisk(0)partition(2)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP
Professional 3gb limited" /fastdetect /3gb /userva=2900 /SOS
/NoExecute=OptIn
multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP
Professional" /fastdetect /SOS /NoExecute=OptIn

WT

 

You might want to refenrence this article:

http://www.solidworks.com/swexpress/pages/jan05/TT_AssemblyDrawingPerformance.html

 

I do not agree with their statement about being fairly meaningless!!! False
information!!

Use of 3GB mode - Windows® XP Pro is required for using 3GB mode. Also, it
is fairly meaningless without 3 or 4GB of RAM. See the Microsoft article for
details on enabling the 3GB mode.

Even if you have less than a GB of physical RAM, it can still open memory
space that might allow you to load something that you otherwise couldn't.
Granted, you are working in the page file and more physical memory is better
& faster, but this switch is still a viable way to utilize more working
memory space for SW. There may be one file that you get from a customer
that you need to open, even if it's slow. This may let you do it. Then if
that size file becomes the norm for you, more memory may be worth
installing, but that's not the issue here.

WT

 

Klaus,

In response to your question about how others handle large assemblies
with many configurations.

We have a standard product consisting of ~5000 parts. This is broken
down into multiple subassembly levels.

We sell the product using a "Pick List" method to add options to a base
standard. Each option means an assembly is either added or deleted,
and in most cases this changes a configuration of a subassembly.

We use configuration specific custom properties to define drawings
numbers. We also have a VB program that uses the sales pick list
(which is an excel spreadsheet) to determine which drawings need to be
released to the production shop for manufacture.

With the options available on this machine, we figure there is over 1
million possible combinations that could be setup. This usually means
that not all configurations that could be sold have been created in the
model. We don't worry about this, but instead create a configuration
after a sell if one isn't yet created. All subassemblies are created,
so detail type drawings are available for the program to fillout and
submit. We will then create the couple layouts for the machine if it
isn't yet available.

We are using 1MHz HP workstations with 2Mram and Quadro 980 xl video
cards. Normally, we will run the program overnight so the drawing set
is ready in the mornings. Although it would take about 3-4 hours to
complete otherwise.

I hope this is helpful knowing how difficult it is to manage large
assemblies.

We have been using Solidworks since the fall of 98, and keep the
software updated. We are currently running on Windows 2000 with SW2005
SP 1.1 (and evaluating SP 2.0)

 

The 3Gb switch helped my 1Gb machine. It gives SW extra breathing room.
What some people don't realize is that during a regen SW may, for short
periods, require considerable blocks of RAM. The 3Gb switch gives that
breathing room.

I've been getting quotes on hardware with dual or quad 64 bit
processors and up to 32Gb of RAM. I do FEA as well and sometimes run
out of RAM and am short on CPU cycles. This stuff isn't cheap, but its
scalable so I can start with a single processor and run 32 bits and
then move on up by adding processors and RAM.