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Guerrilla guide to CNC machining, mold making, and resin casting (2015)

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Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#161

Post by sokoloff »

naasking wrote: post #125
gaze wrote: post #114

Earlier quoted context omitted.

They don’t hold great tolerances, but if that’s ok then they’re fine.

What do you consider a great tolerance?

Not parent, but I’d consider 0.001” over 10” to be totally acceptable for home and hobby use and 0.00025” over 20” to be acceptable for general production use (“great” isn’t really meaningful, but “makes parts to spec” is good enough).

Re: Guerrilla guide to CNC machining, mold making, and resin casting (2015)

#162

Post by gaze »

sokoloff wrote: post #161
naasking wrote: post #125

Earlier quoted context omitted.

What do you consider a great tolerance?

Not parent, but I’d consider 0.001” over 10” to be totally acceptable for home and hobby use and 0.00025” over 20” to be acceptable for general production use (“great” isn’t really meaningful, but “makes parts to spec” is good enough).

That's the specification of a measuring instrument. Commercial VMCs don't hold 0.00025” over 20" even without being loaded. A slight temperature change will throw that off.
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