Engraving Tool Woes

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carbidetooth
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Engraving Tool Woes

Post by carbidetooth »

What tool do I need to do some fine engraving? This is my first go at it. Done with Quick Engrave offset fill toolpath and diamond drag bit.

Image shown is 1 3/8 high. Diamond drag bit seemed like the ticket, but lateral play in the plunger piece and subsequent deflection at the tip sort of shoots its foot. Pretty sure machine is capable, but maybe a more precise (spinning?) bit is needed. Would appreciate advise of those more knowledgeable.
Screenshot (25).jpg
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Tailmaker
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Re: Engraving Tool Woes

Post by Tailmaker »

looks like your drag bit is wobbly. I built one where the drag bit is guided by 2 linear bearings with adjustable pre-load. No backlash and pretty precise traces.
I did some experiments with stainless steel but need to find the pics.
DSC01300.JPG

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carbidetooth
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Re: Engraving Tool Woes

Post by carbidetooth »

Indeed it is wobbly. Enough that I can easily feel it with my fingers. Seems like a built in problem, which surprised me. The idea of linear bearings, perhaps with just a smidge of preload makes real sense to me after seeing how this works. Actually kind of disappointing. I wonder how folks successfully use these?


Is there a commercially made version or do you sell your design?

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Xxray
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Re: Engraving Tool Woes

Post by Xxray »

What bit are you using ? Shouldn't be any play, insert or holder must be defective.

Have used this one for years with no problems in a variety of materials

https://www.ebay.com/itm/CNC-spring-loa ... SwCiRcYI66
Doug

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carbidetooth
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Re: Engraving Tool Woes

Post by carbidetooth »

It appears I got a badly made one.

It was this one:

https://www.ebay.com/itm/CNC-Diamond-dr ... XQVhFR9Tyx

I wouldn't spend the money with those folks again, but that's another story. I may try to peen the end a little on this one before purchasing another. Center pin would have to have some clearance so it could move vertically.

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