DWG file inported into aspire

[nywoodworker]

someone converted this pdf file see attachment [attachment=0]Kiwassa Lake.pdf[/attachment from NY state DEC web page. it was converted into a DWG file. I can not down load it here it is to large 2,358 KB. This is 10 times larger than the pdf file. It opens in aspire but when I try to convert the contour lines into depth the first cut. is well over 500 hours.
I am not sure it appears that the file must have extra data that is making thing take to much time to run.
I really need someone to help me out

[PaulRowntree]

Are you trying to make the contours into shelf-like areas of constant height (a 2 or 2.5D project) , or are you trying to use adjacent contours to set the slopes, and make a true 3D shape?

[nywoodworker]

I was hoping to slope the contour line but at this point i would be happy with having steps. I live in an area that has many lakes and thought offering 3D models would be profitable

[TReischl]

I notice from your post that you are not running a machine at this time?

Tremendous amounts of data do not mean the machine will take longer to cut. I would assume you are getting the 500 hours from the time estimate?

We have no idea of what size tool you are using, how large the job is, etc.

When you load this dwg file into Aspire, how big does Aspire tell you it is? What is the material size that you set?

If you tell Aspire to cut something that fills up a 48 X 96 sheet with a .062 ball nose, it could well take forever to cut.

You could always post the dwg on something like photobucket and allow others to download it so we can see what is going on.

[nywoodworker]

I have a Industrial router with a 4x4 table. I switched to a .5 mill to cut down the time it takes to cut the depth. I also increased the feed rate .The size of the project 1.5 x 18 x24. The first cut is .25 deep and i was using a 75% step over. This first cut take over 500 hours. The DWG file is to large to down loan in here. I would be glade if someone could take a look at the dwg file . Can you tell me how to access photobucket and than I could post it.

[zeeway]

Something does not compute. You have an 18 inch by 24 inch project, and you are doing a roughing cut with a 75% stepover and Aspire says 500 hours? You would have to be using a truly tiny tool to get that. What is the diameter of the tool and the feed rate and depth of cut you are using? Perhaps mm and inches got switched?

Angie

[cac67]

I think you have too many nodes. Select a vector and look at it in node edit mode, I'll bet it will be almost solid with nodes. If it does have a bunch of nodes use fit curves to selected vectors to smooth it out.

[TReischl]

I have a Industrial router with a 4x4 table. I switched to a .5 mill to cut down the time it takes to cut the depth. I also increased the feed rate .The size of the project 1.5 x 18 x24. The first cut is .25 deep and i was using a 75% step over. This first cut take over 500 hours. The DWG file is to large to down loan in here. I would be glade if someone could take a look at the dwg file . Can you tell me how to access photobucket and than I could post it.

Sorry I typed "photobucket" when I meant something like Google Drive, Dropbox, SkyDrive, etc. So many clouds!

If you are running Windows you should have access to SkyDrive/OneDrive (SkyDrive was the old name, it is now OneDrive). It is accessed from from OutLook which is your email program. Look at your email, in the upper left you should have the word "OutLook" with an arrow pointing down next to it. Click on the arrow and you will see a bunch of icons, one of them is OneDrive.

Not to be picky, just trying to help, but you need to post specifics when discussing this stuff, like what feed rate you increased to.

[TReischl]

I think you have too many nodes. Select a vector and look at it in node edit mode, I'll bet it will be almost solid with nodes. If it does have a bunch of nodes use fit curves to selected vectors to smooth it out.

Chris, having too many nodes does not increase the run time of the machine.

[cac67]

I think you have too many nodes. Select a vector and look at it in node edit mode, I'll bet it will be almost solid with nodes. If it does have a bunch of nodes use fit curves to selected vectors to smooth it out.

Chris, having too many nodes does not increase the run time of the machine.

Having too many nodes can increase the run time of the machine. 500 hours is unlikely but inefficient toolpaths are going to cut slower than efficient toolpaths will cut, and a lot of nodes usually indicates a lot of short straight lines that will cause the machine to move in short, jerky moves. It will also show bigger toolpath file sizes.

[ssflyer]

Out of curiosity, what's your scaling factor set to in Aspire for in the estimated machining time? If the DWG file is as simple as the PDF you posted there is likely a problem with the DWG file, assuming your scale factor isn't whacked.

I'll post a DWG file of your PDF in a few minutes - see what happens with that...

[ssflyer]

Try this file, and see if you get similar results...

[TReischl]

I think you have too many nodes. Select a vector and look at it in node edit mode, I'll bet it will be almost solid with nodes. If it does have a bunch of nodes use fit curves to selected vectors to smooth it out.

Chris, having too many nodes does not increase the run time of the machine.

Having too many nodes can increase the run time of the machine. 500 hours is unlikely but inefficient toolpaths are going to cut slower than efficient toolpaths will cut, and a lot of nodes usually indicates a lot of short straight lines that will cause the machine to move in short, jerky moves. It will also show bigger toolpath file sizes.

Chris, he is doing a 3D model, not profiling. I would agree with your statement about nodes causing short jerky moves, no discussion there.

But, if you do not believe me, create an outline with a bagillion nodes, park a model in the middle of it, or even create a model from those vectors. Then do a 3D finish cut on it. Makes no difference.

Remember, when cutting 3D paths, the software is actually working on a pixel representation of the model, not working on nodes or vectors. Vectors are only used to determine the boundary of the cut.

[cac67]

Chris, he is doing a 3D model, not profiling. I would agree with your statement about nodes causing short jerky moves, no discussion there.

But, if you do not believe me, create an outline with a bagillion nodes, park a model in the middle of it, or even create a model from those vectors. Then do a 3D finish cut on it. Makes no difference.

Remember, when cutting 3D paths, the software is actually working on a pixel representation of the model, not working on nodes or vectors. Vectors are only used to determine the boundary of the cut.

I don't see anywhere that he said he created a 3d model from it. I see where he said he would like to but would be happy with steps, but nothing that states he created a model and is running a 3d toolpath.
If he wants to do it as a 3d model I would recommend taking this route.

[TReischl]

I ran a test to double triple check what I posted above.

I created an 18 X 24 job. Then I created two sets of vectors. The first had exactly 4 nodes. The second was the same shape with the sides bowed in about .032 to force the creation of 690 nodes. I then dropped a piece of clipart into the middle. Selected the first vector shape with 4 nodes and processed it. Then I created a second finish cut using the second set of vectors with 690 nodes. Used the exact same tool, same feeds, etc. Here are the results:

The tool was a .125 ball nose with a feedrate of 80 IPM.

Controls work with what is known as a "control loop cycle time". The control is constantly working in a loop, even when nothing is happening. It is waiting to see if the operator pushed a button, if emergency stop was pressed, if a limit switch was tripped, etc. During that loop, it also executes the program if it is RUN mode. The control is constantly running that loop to see if the machine has reached a destination (or an in position tolerance zone which is what it does when not in exact stop mode). When a cut move is comprised of too many short motions the machine can reach the destination before the control has a chance to repeat the control loop. With no input, the machine does not move, hence the jerky moves.

Every control has a different loop cycle time. One of the reasons time estimates are exactly that, estimates. Vectric has no way of knowing what they are, in addition to not knowing the accel and decel of all the machines ever built. So the software did not look at a bunch of short moves and adjust for the control loop cycle time.

In this clip, notice the profile path times. The second one is actually less than the first. The second one is also the one containing 690 nodes. In this case, the path is even longer than the other one because of the slight curves in it. So Aspire does not know that short segments slow down machines. You can further prove this by setting the feedrate to some ridiculously high number that would force the jerky motion on a machine (the jerkiness is directly related to feed rate) and there is still no indication from Aspire that path will be cut any slower.

A better question here is why is the path with the 690 indicated as cutting faster? We all know that a straight line is the shortest and fastest distance between two points.

Machines that can run really, really fast, like the 2400 IPM one sees on things like sail cutters, lasers processing thin sheet metal (not lasers based on galvo mirrors) are normally running parallel processing. Instead of having one cpu do everything, they offload the actual motion control onto a second processor which can run a really tight, fast loop which is then reported back to the main loop. Since the main loop does not have to include motion control, it can run much faster.

I have seen a very sophisticated control that uses 12 cpu's to control a machine. It is very fast and processes itty bitty tiny line segments like they are a nice big smooth curve. It cuts true arcs faster, because in the digital world, that circle the machine cuts is actually very small moves generated by the control.