small radius on inside corners

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FredrikB
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small radius on inside corners

Post by FredrikB »

Hi

I am rather new working with Aspire and have a little problem that I would like to solve.

I should cut out (profile toolpath) some letters in 10mm acrylic, these letters should be placed as fronts on some hollow aluminium letters.
There will be a profile on the edge of the acrylic so 7mm will go down in the aluminium letters and the rest 3mm will be above.
There is an offset of 5mm between the 3mm edge and the 7mm edge so you would not see the edge of the aluminium letter from the front.
Inside the aluminiumletters there is led so the acrylic will light.

I want the inside corner radius to be so small as possible so I have used a 3mm bit when I make the letters before.
But I takes so long time with the small 3mm bit.
I would like to use a 8mm router bit instead and then fix the inside corners with a 3mm bit.
Is there any setting that can fix this?
I use a TigerTec with automatic tool changer.

Know that there is a option (use larger area clearance tool) on pocket toolpath that can fix it when you make a pocket.
But I can’t find it on the Profile toolpath.

best regards Fredrik

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TReischl
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Re: small radius on inside corners

Post by TReischl »

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garylmast
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Re: small radius on inside corners

Post by garylmast »

Draw a smaller rectangle in each corner, then mill inside that with the smaller bit.

Gary
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plcamp
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Re: small radius on inside corners

Post by plcamp »

garylmast wrote:
Sun May 03, 2020 8:11 pm
Draw a smaller rectangle in each corner, then mill inside that with the smaller bit.

Gary
If you are machining an inside corner of a pocket, you will never get a sharp or 'square corner. The reason for this being the cutter used for machining, this is what creates the corner radius. The tool diameter/2 = tool radius and this is always what will remain. The trade-off is how small of a tool you willing to use and what would be the minimum acceptable corner radius.

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martin54
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Re: small radius on inside corners

Post by martin54 »

How big are the letters & what is the viewing distance? If this is for something like a shop front then I wouldn't worry to much about it, I do this sort of thing with a 6mm bit & when viewed from a few feet away you can't really see that the corners have a radius on them :lol: :lol:

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Jim_in_PA
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Re: small radius on inside corners

Post by Jim_in_PA »

Cut the profile as you do with a slight allowance and then run the same toolpath without the allowance and a smaller cutter. Since you're removing only a small amount of material with the "tiny" bit, the cut should be nice and it will get the corner sharper than you can with a 3mm tool. I often use a 1mm or 1.5mm cutter for this kind of cleanup for inlay pockets I create for a client. The statement that you can't get a true "sharp" inside corner with a rotating tool is correct, however. But scale matters and you can get a "visually square" corner with small tooling. Be sure that the cutter you use is appropriate in geometry for your material.

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martin54
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Re: small radius on inside corners

Post by martin54 »

But scale matters and you can get a "visually square" corner with small tooling. Be sure that the cutter you use is appropriate in geometry for your material.

That's why I asked about letter size & viewing distance Jim, if you have 2 foot tall letters 20 feet off the ground even a 6mm radius isn't going to be noticed unless someone gets the Binoculars out :lol: :lol: :lol:

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Jim_in_PA
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Re: small radius on inside corners

Post by Jim_in_PA »

martin54 wrote:
Mon May 04, 2020 4:08 pm
That's why I asked about letter size & viewing distance Jim, if you have 2 foot tall letters 20 feet off the ground even a 6mm radius isn't going to be noticed unless someone gets the Binoculars out :lol: :lol: :lol:
True dat!

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