Litho gone wrong

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Xxray
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Litho gone wrong

Post by Xxray »

Greetings, hope all is well with everyone, haven't posted in a while.

Did this 10x6" litho for the daughter of a deceased friend, RIP Bro John. Don't know why it cut through, rarely ever happens to me and usually .21 max depth is fine, but thats not what I'm asking about [obviously will have to redo it]

Took an inordinate amount of time, well over 8 hrs, and I know for sure I have made lithos this size and bigger in half the time. Usually just keep all my settings the same. the .03 for the bit I got from some calipers, is a 1/32 bit BN, obviously I can increase line spacing, what do you pros usually use for something this size ?
IMG_6381.jpg
IMG_6382.jpg
Doug

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Xxray
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Re: Litho gone wrong

Post by Xxray »

Can't edit anymore at all [nevermind, I see it]?
Thought I'd say, ironically, vcarves time estimate was like 90 minutes.
Doug

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Adrian
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Re: Litho gone wrong

Post by Adrian »

The estimate is meaningless until you've set the scale factor for the type of job being done, VCarve has no idea what the acceleration/deceleration settings and capabilities of the machine being used are. That becomes a bigger and bigger discrepancy the more three axis movement there is and there's a lot in a litho.

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adze_cnc
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Re: Litho gone wrong

Post by adze_cnc »

Here's where relying on percetage stepovers can deceive: 11% looks big; 0.003 inches is very small (your basic thickness of a yellow sticky note).

For 2900 goodly sized lines I can easily imagine 8 hours.

GEdward
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Re: Litho gone wrong

Post by GEdward »

I am by no means a "pro" but it seems to me that a plunge rate of 30ipm is a bit slow for a machine capable of machining at a 300ipm feed rate. I'd double the Z axis feed rate if the machine is capable of it. I can't see your rapid clearance gap setting. I have found some improvement in machining time by setting it around 0.03. I've seen a number of examples of your litho work and most of it is quite good.

Ed

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Xxray
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Re: Litho gone wrong

Post by Xxray »

was pretty hazy last night, settings i used were when I was doing 3" square night lights so indeed, need to jack up line spacing
Doug

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