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Alright I've got a project for my engineering class to create a historical object from scratch using your own design. I'm making a guillotine and have so far made a rough prototype(pic related) The way it's designed is that there's a 3/4" steel pipe on each side and a piece of wood holding the blade, which is connected to a couple pieces of PVC pipe that slide up and down the steel pipe. The only problem I'm having so far is that there's a tiny difference in the diameter of the pvc pipe and the steel pipe, so the wood+blade wiggle around going up and down. I tried packing the pvc with tape to fill the gap but even then it was still wiggling around too much. Any more tape and it was too tight. Anyone know how I can get this gap filled without making it too tight?
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Here's a closer look at the gap
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>>1143637
you want it to be loose, otherwise it will be slow when it chops down, it needs to be fast and does a free fall
but why are you not using your own design?
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that is so badly made
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>>1143670
Not meant to be good. Just threw some shit together to see if it'd work
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>>1143672
Fair enough. Who's it going to be demonstrated on?
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A longer peice of PVC would reduce the "tilt". I tink you'll need this to keep one side from dropping faster and binding. I don't think filling the gap with that short piece will help much.
Tweaking the spacing between the metal pipes to put the gap either inside or outside on both sides would also help.
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Try a linear bearing instead.
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>>1143725
I didn't even know these existed. What kind of force can they take? Also OP could cheap out and use some sort of sliding door/curtain/drawer rail if it's long enough, the bits that fix to the drawer/door have bearings if they're good enough.
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>>1143729
They're used all the time in 3D printers.
As for forces, I'm not really sure.
I just figured it'd be an excessive solution for his needs, if he felt like spending ~20-30 bucks on getting an astroglide fit.
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I'm thinking the PVC is the problem. Maybe the softer material is having friction problems from rubbing on the metal. Use a metal pipe in place of PVC and the friction issue should go away.
This>>1143725
seems like a good idea, but just getting a steel pipe to cut is likely cheaper and easier to find.
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>>1143725
This is probably overkill. Some brass bushings and polished steel rods would be ideal. And OP do not install the blade without some sort of safety.
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>>1143637
>create a historical object from scratch using your own design
>historical object from scratch
>using your own desing
When the only relevant answer is a *working* gas chamber.
But the you figures out that gas chamber never happen in history so you can't claim them being historical and masterrace your own design
>picrelated.jpg
you dun goof'd
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