# Tag Info

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An NC machine, instead of having wheels like a manual machine, accepts instructions and numbers. But unlike a CNC machine, a computer is not feeding it those instructions and numbers. An NC machine comes with a special typewriter thing that you use to write your program and it produces the punch cards or magnetic tapes that the NC machine accepts. You then ...

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The cutting blanks equation is, $$F=l*t*s$$ L=length mm t+thickness mm s =shear N/mm^2 We measure the perimeter of the blank and then add the circumference of the two holes. $\text{The straight sides are 2*70mm =140mm and 2*( 70-40-20=10)mm=20mm =160mm}$ $\text{half circles are 2*pi*20=125.66mm, inner holes 2*2*pi*15=188.49mm}$ \$\text{ Total 188.49+124.66+...

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So why not calculate the cut length ie perimeter and use that with the thickness - the cut length is what you get with pi * D in your single blanking example.

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As you don't have a mill or a lathe, I don't see much options here. Brazing is a very strong joint if done properly (nearly as good as welding). You could also drill, tools permitting, a round keyway or keyways.

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A shrink fit is possible, but do you have the mill or lathe to make the appropriate dimensions and then sufficient heating and/or cooling? Liquid nitrogen is a possibility, but a household freezer is about -18 deg C and a household oven about 280 deg C, which means a delta T of 300.

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Well, the question has already been accepted, however. I'll mention something regardless. First of all, it's perfectly fine to use a plain threaded rod for linear motion. You mostly simply need to consider what your basic requirements are, and your willing budget. What I'm most surprised about, is that no-one here even considered to mention all the ways you ...

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You can use regular threaded rod as a lead screw. The size and pitch (and grade) of the thread will determine your precision but 0.5 mm seems overkill for furniture positioning. The smaller the screw the finer the pitch and therefore precision will be, but at the cost of reduced load capacity. Just keep the rod lubricated and you shouldn't have issues.

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It's not exactly clear to me what you mean by trapezoidal thread rod. Like you noticed Metric threads are also trapezoidal (just like ACME with slightly difference face angels). Figure : Common types of bolts (source linearmotiontips) To my understanding (from the context of the question) the main differences that you are likely to find between the ...

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