Cut 3D - does not "see" holes in model

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draconidus
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Cut 3D - does not "see" holes in model

Post by draconidus »

Hi all,
I hope someone has struck this curious problem before.
This problem persists with both WRML & STL formats that I read into Cut3D.
I save my Solidworks model in both WRML & STL format. I then import into Cut3D and setup tool-paths (usually finishing&cut out).
I then notice in the preview that my 3mm screw holes in the model do not appear. Why is this :?:
The generated Gcode does not contain the hole information -

If I create a 2D DXF and read it with Cut2D - the holes are there. This problem is only happening with 3D files read into Cut3D.

Thanks in advance :)

tmerrill
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Re: Cut 3D - does not "see" holes in model

Post by tmerrill »

Without a file to look at it is going to be somewhat of a guessing game. First thing I thought of was what size bit are you using and will it fit into a hole that size?

If you can't post the model, consider sending it directly to Vectric support (support@vectric.com) and let them look at it.

Possibly a better approach is to use Cut3D to generate the finish and cutout toolpaths, then import the file into Cut2D and set up drilling toolpaths to do the holes. You will get much better results creating holes like this with a 2D drilling toolpath rather than a 3D finish pass.

Tim

draconidus
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Re: Cut 3D - does not "see" holes in model

Post by draconidus »

Thanks for the reply Tim.

I did in fact resort to loading a 2D DXF into Cut2D just for the drilling path to cover the immediate situation. But I would still like to know if I am doing something wrong.

I have attached the WRML & Solidworks files in case anyone is interested in checking whether there are issues with the geometry.

Best
Draco
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hex-landing-gear-curve-lhs.zip
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Adrian
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Re: Cut 3D - does not "see" holes in model

Post by Adrian »

As Tim says if the tools you're using are larger or (if Cut3D works the same way as the other Vectric products) exactly 3mm then they're not going to be able to cut a 3mm hole.

I think that's almost certainly the problem as I scaled the model up and cut with a 1/4"and 1/8" bit and the holes came out fine. Scaling it down so the holes were less than 3mm and the holes disappeared.
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Capture.PNG

tmerrill
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Re: Cut 3D - does not "see" holes in model

Post by tmerrill »

Draco,

I'm going to change the subject slightly.

For this part, and ones of similar design, I would not use Cut3D at all - it is not the best program for the job. This part can be machined quickly and more accurately using simple 2D toolpaths in Cut2D. Plus you could easily layout multiple parts on one piece of material.

Preview below is from using the vectors obtained from your .wrl file (you would have the .dxf files) and using 3 toolpaths in Cut2D, drilling for the holes, pocket for the slot and lower recess and profile to cutout. The vectors determine the size in X and Y, the cut depths for the toolpaths determine the height in Z. Plus the drilled holes will be perfect with straight, smooth sides and accurately placed.

Just something for you to consider, but whenever you have a design like this the frustration level will increase trying to set up any 3D toolpath for acceptable results. Not saying it isn't possible, but that you are asking the program to do something it wasn't intended to do.

Tim
Attachments
Landing gear with Cut2D.JPG

draconidus
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Re: Cut 3D - does not "see" holes in model

Post by draconidus »

wow!! Thank you all very much for your responses :!:

@Adrian - I see what you mean. I edited the model to size the holes out to 3.1mm and they appeared. Armed with this new knowledge, I will avoid this in future.

@Tim - Well Tim , I am impressed and very grateful to you for sharing this knowledge. You make me realize what a newbie I am with Vectric (in the nicest of ways).
I have been wrestling with getting multiple parts out of a piece of material. You say, I you could easily layout multiple parts on one piece of material so there is my next challenge.
I did try to use Cut2D for the whole job but I found that I had to create 2 rectangular shapes to get the pocket paths because Cut2D could not (would not) break the curves at the pocket corners. I did set up with drilling for the holes, pocket for the slot and lower recess and profile to cutout. Guess it's a case of me not knowing enough when it comes to Cut2D/3D, but that I can fix.
So I take it that you converted the WRL file to a DXF. Did you convert to a 2d or 3D? (I suspect Cut2D only reads 2D).
Fully understand your point regarding asking the program to do something it wasn't intended to do, and I agree fully. This is not the way I like to work.

You guys have made a huge difference ,thanks again for the guidance. :wink:

Draco

tmerrill
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Re: Cut 3D - does not "see" holes in model

Post by tmerrill »

Draco,

I imported your .wrl model into Aspire and that has a tool to quickly trace 3D objects. This vector trace was then exported from Aspire and imported into Cut2D.

Cut2D does not have this ability to trace 3D objects, in fact is can't even load 3D objects, but the program is really designed to toolpath vector designs created in another CAD program. I am not familiar with other CAD programs, but if you have one that will create and export .dxf or .eps files, you can do all the vector work in that, then export/import into Cut2D and toolpath. In essence, that is what I did - used Aspire to create the vectors and exported/imported into Cut2D where the toolpaths were set up.

In case you aren't aware of them, you can find some tutorials for both Cut2D and Cut3D here and they are worth your time to watch:

http://www.vectric.com/WebSite/Vectric/ ... orials.htm

And never hesitate to ask any questions. If possible, including a file and/or pictures normally helps get a faster response, and there are many here very willing to help.

Tim

JimG
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Re: Cut 3D - does not "see" holes in model

Post by JimG »

draconidus wrote:@Adrian - I see what you mean. I edited the model to size the holes out to 3.1mm and they appeared. Armed with this new knowledge, I will avoid this in future.
Draco,

My quick and dirty way of getting around holes or spaces the exact size of the cutter is to reduce the cutter diameter by a very small amount in the tool database - in your 3mm hole case, reducing the cutter diameter to something like 2.999mm. It means that the actual 3mm cutter will cut very, very slightly oversize, but it might be an easier fudge than going round and altering all the hole sizes in your CAD drawing.

Jim.

draconidus
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Re: Cut 3D - does not "see" holes in model

Post by draconidus »

@ Tim
Thanks for this :wink: I will curb my eagerness and sit through the tutorials. I can export DXFs and in fact this is what I did after reading you last post and got the paths out in Cut2D. It all worked very well and (as you pointed out in earlier posts). I feel better now that I am utilizing the tools' capabilities to a fuller extent.

@ Jim
I think that reducing the cutter diameter by a very small amount in the tool database in the right place to do it. I will be applying this approach when I use Cut3D in future. I agree, it is an easier fudge than going round and altering all the hole sizes in the CAD drawing. :(

Great information - excellent help - hope I can repay one day soon.

Cheers
Draco

draconidus
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Re: Cut 3D - does not "see" holes in model

Post by draconidus »

tmerrill wrote:Draco,

I'm going to change the subject slightly.

For this part, and ones of similar design, I would not use Cut3D at all - it is not the best program for the job. This part can be machined quickly and more accurately using simple 2D toolpaths in Cut2D. Plus you could easily layout multiple parts on one piece of material.

Preview below is from using the vectors obtained from your .wrl file (you would have the .dxf files) and using 3 toolpaths in Cut2D, drilling for the holes, pocket for the slot and lower recess and profile to cutout. The vectors determine the size in X and Y, the cut depths for the toolpaths determine the height in Z. Plus the drilled holes will be perfect with straight, smooth sides and accurately placed.

Just something for you to consider, but whenever you have a design like this the frustration level will increase trying to set up any 3D toolpath for acceptable results. Not saying it isn't possible, but that you are asking the program to do something it wasn't intended to do.

Tim
Hi Tim,
One more question please.
How did you get Cut2D to trace the pocket tool path following along the contour of the drawing? I can only manage to set up a pocket tool path for this part if I draw a rectangle using the polygon tool to mark the pocket tool path. Problem is this then leaves a rectangular foot print on the material. I still get the part cut out as designed (because the cut out tool path cuts the outline) but the machine time would be decreased if it only cut along the contour of the part rather than having to over cut because I have "fudged" the pocket outline. Hope the attached pic illustrates my point in question.

Cheers & Thanks
Draco
Attachments
Polygon drawn over intended pocked to provide pocketing path.
Polygon drawn over intended pocked to provide pocketing path.

tmerrill
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Re: Cut 3D - does not "see" holes in model

Post by tmerrill »

Hi Draco,

I did that part in Aspire which has some tools to support it. I had assumed you could do this in your CAD program where you could create all the vectors and export/import them as a .dxf file.

In Cut2D this is still possible but will take a few extra steps. One thing to realize is you will want the pocket toolpaths to extend some past the left and right sides of your drawing so you get good clean edges. The top and bottom edges you want perfectly aligned with the original drawing.

What you need to use is called Node editing and you can find it explained in the Help Contents, but here is a quick introduction.

Starting with what you have shown in the picture, you can select the rectangular shape, press 'n' (the shortcut key for Node editing), then hover the mouse pointer over the left side and right click. In the menu that opens, convert the line to a Bezier and then adjust the Bezier to follow the general shape of the object. You don't need to be exact. Then do the right side the same way. You can also select nodes (the squares) and use the arrow keys to nudge them into position with more control over them. For exact control, you can right click on a node and select Properties, then enter an exact X,Y location.

Give it a try and ask if something doesn't make sense.

Tim

draconidus
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Re: Cut 3D - does not "see" holes in model

Post by draconidus »

tmerrill wrote:Hi Draco,

I did that part in Aspire which has some tools to support it. I had assumed you could do this in your CAD program where you could create all the vectors and export/import them as a .dxf file.

In Cut2D this is still possible but will take a few extra steps. One thing to realize is you will want the pocket toolpaths to extend some past the left and right sides of your drawing so you get good clean edges. The top and bottom edges you want perfectly aligned with the original drawing.

What you need to use is called Node editing and you can find it explained in the Help Contents, but here is a quick introduction.

Starting with what you have shown in the picture, you can select the rectangular shape, press 'n' (the shortcut key for Node editing), then hover the mouse pointer over the left side and right click. In the menu that opens, convert the line to a Bezier and then adjust the Bezier to follow the general shape of the object. You don't need to be exact. Then do the right side the same way. You can also select nodes (the squares) and use the arrow keys to nudge them into position with more control over them. For exact control, you can right click on a node and select Properties, then enter an exact X,Y location.

Give it a try and ask if something doesn't make sense.

Tim
Hi Tim,
Thanks for understanding my eagerness. Of course, I had to actually go into node edit mode to adjust the shape of the rectangle for my earlier example. Would you believe that while I was doing this I did not notice that the pointer changed to "~" each time I hovered over the line LOL. Naturally once I realized this was actually indicating spline options (after reading your reply) it all made sense.
I have attached the result below. :) I promise I'll return to the tutorials now. :wink:

Cheers
Draco
Attachments
grab.jpg

tmerrill
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Re: Cut 3D - does not "see" holes in model

Post by tmerrill »

Hi Draco,

You are catching on real fast and don't think you'll have any problems.

I'm curious. These parts are labeled as landing gear - can you share a picture of what they will be used on or provide any other details?

Tim

draconidus
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Re: Cut 3D - does not "see" holes in model

Post by draconidus »

Hi Tim,
Apologies for the tardy reply...got busy at work so no time to pursue interests :(
I expect to cut the part this weekend so I will post pics and explain the whole thing. I ran a test by cutting my son's name out of 8mm transparent acrylic (using two depth passes) and it turned out OK but I think that I need more speed to get a nice smooth finish on the acrylic. I am currently using a dremmel 300 which is fine for up to 6mm depth but I think it is asking too much for it cut 8mm acrylic (other stuff like HDPE, Nylon is ok at that depth).
So in preparation for the job I will be mounting an 800W router head (1/4" schank) and I hope this improves the edge smoothness. Not that there is a great deal wrong with it - It is just not as smooth as one might like - I have to take to it with a file and "clean" out the tiny ridges. I have been reading about "feed & Speed" and made changes to these settings to see what happens but this has not yielded spectacular results and I suspect it is because the actual router is not up to these tasks.
I will update you once I have run the job.

Cheers
Draco

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