Fasteners not fitting

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svobodat59
Posts: 7
Joined: Wed Aug 26, 2020 6:18 am

Fasteners not fitting

Postby svobodat59 » Wed Aug 26, 2020 6:25 am

Hello everyone,
I just started trying the Fasteners workbench. I printed several pairs on nut/bolt (M8 - M20) on my new Prusa mini and none of them fit each other.
Am I missing some important parameter?
Could the properties "match outer" and "offset" have something to do with this? (I did not find any explanation for them)

Thank you
Tomas
chrisb
Posts: 30663
Joined: Tue Mar 17, 2015 9:14 am

Re: Fasteners not fitting

Postby chrisb » Wed Aug 26, 2020 7:05 am

Hi and welcome to the forum!

That's not a problem of FreeCAD, it's a problem of the printer or the printing process in general. If you measure your nuts and bolts you find that they don't match the stl or obj which you exported. For validation you can re-import these files and check them.

To compensate you can load Fasteners workbench and then customize nuts and bolts in the preferences.
You need at least FreeCAD 0.19.23300 to edit my current sketches.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
Jee-Bee
Posts: 2187
Joined: Tue Jun 16, 2015 10:32 am
Location: Netherlands

Re: Fasteners not fitting

Postby Jee-Bee » Wed Aug 26, 2020 4:12 pm

I never understood why print fasteners.
just print a hole and use inserts(https://www.pemnet.com/fastening-produc ... r-plastic/) and buy some fasteners
svobodat59
Posts: 7
Joined: Wed Aug 26, 2020 6:18 am

Re: Fasteners not fitting

Postby svobodat59 » Wed Aug 26, 2020 7:11 pm

The dimensions seem to be OK.
Rather it seems that the inner and outer thread are exactly the same and therefore have no clearance to allow them to enter each other. Is there any way in the Fasteners settings to influence this ?

BTW: Is this the correct forum for discussing the problems of an addon workbench?
chrisb
Posts: 30663
Joined: Tue Mar 17, 2015 9:14 am

Re: Fasteners not fitting

Postby chrisb » Wed Aug 26, 2020 9:18 pm

svobodat59 wrote:
Wed Aug 26, 2020 7:11 pm
Is there any way in the Fasteners settings to influence this ?
How about reading the comments given here?
chrisb wrote:
Wed Aug 26, 2020 7:05 am
To compensate you can load Fasteners workbench and then customize nuts and bolts in the preferences.
You need at least FreeCAD 0.19.23300 to edit my current sketches.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
User avatar
shaise
Posts: 376
Joined: Thu Jun 11, 2015 8:11 am

Re: Fasteners not fitting

Postby shaise » Wed Aug 26, 2020 9:35 pm

svobodat59 wrote:
Wed Aug 26, 2020 7:11 pm
Is there any way in the Fasteners settings to influence this ?
Indeed there is, as chrisb mentioned already before: select the fastener workbench, goto Edit -> preferences. Select Fasteners on the left. In the fastener settings there is a "Tread generation" option. If you select "3D printer compatible", all fasteners will have a dimension compensation for 3d printing. The default parameters are a good start, but you might want to tweak them based on your printer and filament.
It is important to note that if you already generated some threads, they will not be affected by the new settings until you recompute them.

shai
svobodat59
Posts: 7
Joined: Wed Aug 26, 2020 6:18 am

Re: Fasteners not fitting

Postby svobodat59 » Wed Aug 26, 2020 9:39 pm

Thanks a lot SHAI ! Yes this is what I was looking for.
svobodat59
Posts: 7
Joined: Wed Aug 26, 2020 6:18 am

Re: Fasteners not fitting

Postby svobodat59 » Wed Aug 26, 2020 9:43 pm

Jee-Bee wrote:
Wed Aug 26, 2020 4:12 pm
I never understood why print fasteners.
just print a hole and use inserts(https://www.pemnet.com/fastening-produc ... r-plastic/) and buy some fasteners
Actually all I would use from the Fasteners menu is a threaded rod and a "screwtap" to cut its opposite. The rest of the detailed fasteners I don't need. I am speaking here about large plastic threads like M24, not something easy from the hardware store.