Fasteners Workbench thread and head scaling

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Frank Sonne
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Re: Fasteners Workbench thread and head scaling

Postby Frank Sonne » Fri Oct 04, 2019 11:56 am

shaise wrote:
Fri Oct 04, 2019 11:17 am

This might look like a screw, but actually its a "reversed screw" that is specially designed to make tapped holes into solids. When using the 3D printed mode, this "screw tap" is getting wider, creating the necessary space tolerance similar to nuts. It can have arbitrary length.

shai
First, Fantastic Fastner tool Shai.

That is the icon i use, the problem is, i use the same for BOTH parts, so what you are saying is i need the ScrewTap for one part, and a Cut M42 BOLT for the other, for 3D printing to work for me? I cannot use the same ScrewTap for both parts. Is that my problem? Would REALLY like to get it right for the next print :o)
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shaise
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Re: Fasteners Workbench thread and head scaling

Postby shaise » Fri Oct 04, 2019 12:09 pm

Frank,

Thank you for the kind words, but the big thanks are for Ulrich1a - he made the screws, I just organized it in a workbench.
The screw-tap profile is made specially for inner threads, it can not be used as an outside thread (the profile is different - the ends are rounded rather then flat) So yes, basically, you will need to cut an existing M42 to get the counter part.
To make tests without wasting time/material you can try printing say 1cm high of completely empty solid (no infill, no top/bottom plates). its weak, but a good and fast test.

shai
Frank Sonne
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Joined: Thu Oct 03, 2019 12:15 pm

Re: Fasteners Workbench thread and head scaling

Postby Frank Sonne » Fri Oct 04, 2019 12:48 pm

Thx Shai,

that got me on my way :)

What would it take to have option in the ScrewTap to tell if its a Bolt or Nut, so it uses the appropriate Screw/Nut Scale?

I've made M42 Screw, where i cut off the top and bottom, so it has the right Height, for what i need, and then made the pockets and ScrewTaps i needed in the part, now i need to print it, but i really messed around with the values without writing the Default settings down.

As far as i remember its
Screw Scale
A: 1,020
B: -0.020

Nut Scale
A: 1,030
B: 0,100

Does anyone remember if that's correct?
Frank Sonne
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Joined: Thu Oct 03, 2019 12:15 pm

Re: Fasteners Workbench thread and head scaling

Postby Frank Sonne » Fri Oct 04, 2019 1:45 pm

Setting on Screw Tap is not possible, as you say they have different threads, but what is missing from the Fastner collection is a threaded rod, which can be gotten, as i did, through cutting top and bottom off a bolt. Sadly not all bolts can do M42, and some are even missing some of the ScrewTap sizes, but it looks like it works, so going for a print.

I guess that's the kind of problem you run into, when you are not an engineer, and know what things are called :o)

Started printing the full 2 parts, i trust it correct this time around :)
Frank Sonne
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Joined: Thu Oct 03, 2019 12:15 pm

Re: Fasteners Workbench thread and head scaling

Postby Frank Sonne » Fri Oct 04, 2019 1:48 pm

Putting the 2 parts together in Simplify 3D even show they now fit, so got it right this time around.
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shaise
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Re: Fasteners Workbench thread and head scaling

Postby shaise » Fri Oct 04, 2019 1:52 pm

Default values:
Screw Scale
A: 0.990
B: -0.050

Nut Scale
A: 1.030
B: 0.100

However different printers / different print settings, might need to adjust these values by trial and error. There is no shortcut...
shai
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shaise
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Re: Fasteners Workbench thread and head scaling

Postby shaise » Fri Oct 04, 2019 1:53 pm

And yes, I agree, a threaded rod should be added...