Limit work depth in 3d roughing toolpaths

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tahustvedt
Vectric Craftsman
Posts: 107
Joined: Mon Sep 03, 2007 9:08 pm

Limit work depth in 3d roughing toolpaths

Post by tahustvedt »

I would really like to be able to set a maximum work depth when I rough cut 3D models. I like to leave a few mm of material left all around the piece, which is removed when finishing, for superior support of the part. To achieve this now I have to trick Aspire into doing what I want. Either by roughing a smaller area than the part and then profile, or by fiddling with the zero or pass depth. I'd love it if instead I could set it to only go down a certain depth. Please add this in future versions, unless I've missed an obvious function in the menu. :)

GraClay

Re: Limit work depth in 3d roughing toolpaths

Post by GraClay »

Is this what you are looking for?
Attachments
roughing parameters.jpg

tahustvedt
Vectric Craftsman
Posts: 107
Joined: Mon Sep 03, 2007 9:08 pm

Re: Limit work depth in 3d roughing toolpaths

Post by tahustvedt »

Not exactly. I need to stop at a certain depth around the part, but still rough close to the 3D part surface. If I set that value to 5 mm, for example, the toolpath calculations take half an hour, and leaves a lot of mmterial to remove at finishing. I want the finishing pass to cut all the way down around the part, to 43 mm depth, but I need the roughing pass to stop at 35 mm to leave 5mm of material to hold it together. The wood is 40 mm thick, and the tool is 6mm. When I cut end grain surfaces it will break up too easilly if I just use tabs.

tmerrill
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Re: Limit work depth in 3d roughing toolpaths

Post by tmerrill »

What I have done is to create a "machining base" using the Create Shape tool and flat Planar surface option. Make it larger than the model and set the height to the amount of material you want to leave.

Then set it's combine mode to Merge and have both it and the model visible (box checked next to the component name) when you calculate the 3D Roughing Pass. The depth of the roughing pass around the model will be set by the thickness of the machining base.

Now, uncheck the machining base to make it invisible and calculate the 3D Finish toolpath with only the model visible. Now the finish pass will extend to the bottom of the model, which is what I think you are asking for.

The use of a vector machining boundary during this process is critical, but I think you already have that figured out.

Tim

tahustvedt
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Re: Limit work depth in 3d roughing toolpaths

Post by tahustvedt »

Thanks. That's a trick I haven't thought of yet. :)

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mtylerfl
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Re: Limit work depth in 3d roughing toolpaths

Post by mtylerfl »

tahustvedt wrote:Thanks. That's a trick I haven't thought of yet. :)
You can see an example of this 'similar' technique on the Seahorse Corbel project I designed for Vectric back in July 2012. If you expand either one of the Model groups in the modeling tab, you will see an item I named "Bit Stop Plane". It is only 0.125" thick in this case, but suitable for those particular models. I usually make "bit stop" planes thicker for most projects. I believe I've used similar planes on a couple (or more) other public Vectric free projects, but the Seahorse one was the first that came to mind.

Here's a link to the Seahorse Corbel project:

http://www.vectric.com/cool-stuff/proje ... rbels.html
Michael Tyler

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facebook.com/carvebuddy

-CarveWright CNC
-ShopBot Buddy PRSAlpha CNC

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