Machining a 10mm diameter recess 4mm deep

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Soapyjoe
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Machining a 10mm diameter recess 4mm deep

Post by Soapyjoe »

Hi Everybody,

Simple question, I think, but I am not happy with the results I have been getting so far.

I am making a dust shoe and need to machine four 10mm diameter recesses 4mm deep for the magnets.
Ideally I would like to machine the whole component with, say, a 6mm slot drill but find that the magnet recesses display a very jerky movement.

I have tried altering the machining specifications for the 6mm tool with less than satisfactory results.

What am I doing wrong ?

I could go to the expense of buying a 10mm slot drill a just drilling the holes but do wonder if there is a better way of doing it.

Soapy

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Adrian
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Re: Machining a 10mm diameter recess 4mm deep

Post by Adrian »

I'd use an inside profile toolpath with a bit bigger than 5mm but less than 10mm (6mm would be ideal) and set it to a cut depth of 4mm with perhaps a spiral ramp set.

Hard to say what is causing the jerky movement without more info. Could be that the movement speed is too high and the control software is not smoothing it out correctly.

Soapyjoe
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Re: Machining a 10mm diameter recess 4mm deep

Post by Soapyjoe »

Thanks Adrian,

Nice answer.... I consider this feature (The Forum) of the Vectric software a great asset.

I have not tried your suggested method yet....... but feel certain this method will work well.

Thanks once again

Soapy

Soapyjoe
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Re: Machining a 10mm diameter recess 4mm deep

Post by Soapyjoe »

Adrian,

Just made a quick trial on the machine.... cutting the magnet recesses with a 6mm slot drill, as you suggested, works well

fixtureman
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Re: Machining a 10mm diameter recess 4mm deep

Post by fixtureman »

Are you drawing it in Aspire or are you using a cad program or inkscape to draw it then import it.

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martin54
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Re: Machining a 10mm diameter recess 4mm deep

Post by martin54 »

If you were using a pocket toolpath then the jerky movement as you described it is simply because the machine was moving a very short distance between its changes of direction, slowing your feedrate right down would improve this to some degree but probably never get rid of it entirely. The machines weight & rigidity will play a large factor which you can't really do anything about :lol: :lol:

Best option I have found & one that I use a lot when wanting to cut small or narrow pockets is to use Adrians suggestion of a profile cut inside the line, normally as Adrian also suggested using a spiral ramp :lol: :lol:

DLWOODWORKS
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Re: Machining a 10mm diameter recess 4mm deep

Post by DLWOODWORKS »

In case this hasn't been suggested, make sure your circles are true circles and not vectored circles. I've been burned by this a couple of times. A true circle has besier curves and smooth points. A vectored circle is made up of tons of vectors forming a "circle". Each vector requires the machine to perform a small incremental move versus smooth moves.

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mtylerfl
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Re: Machining a 10mm diameter recess 4mm deep

Post by mtylerfl »

DLWOODWORKS wrote:...A true circle has besier curves and smooth points...
I think you mean arcs (not Bezier, although Bezier curves are better than the "stepped straight lines" versions of "circles")
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BalloonEngineer
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Re: Machining a 10mm diameter recess 4mm deep

Post by BalloonEngineer »

I always convert Bezier curves to arcs and lines ("Fit curves to Vectors"). There is no g-code for a Bezier, so it always results in toolpaths using the dreaded short line segments, instead of arcs and lines which do translate directly into G2 and G1 commands. I do keep the unconverted Bezier on another layer for editing purposes, I copy the vectors to another layer before converting and creating toolpaths.

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