P-TET-000019 Shutoff valve thru body - Design Updates

[mechatroniks-git]

• O-ring grooves too tight
• OD fit with SLA tetra valve was ok, but with FDM shutoff valve, it was a bit tight
• Pocket to hold nut needs to be changed so that nut doesn't spin
• Consider modifying pocket to hold nut such that nut kept centered during assembly (drop in to shallow pocket?)
• Emboss part number on model

[cyunis]

Videos from 7/20:
Archive.zip

[mechatroniks-git]

[jgrano]

Took all above notes into consideration rework of this part. Will reprint 7/23 and verify fit w/o o-rings

[Judoguy12]

John, when you save the part you could put in the reason for saving the issue number so it is traceable

…

On Thu, 23 Jul 2020, 22:45 jgrano, ***@***.***> wrote: Took all above notes into consideration rework of this part. Will reprint 7/23 and verify fit w/o o-rings — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#98 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AHE6JJPWSBKRAJPD7ZKQST3R5CVQPANCNFSM4PEC6TPA> .

[jgrano]

@Judoguy12 so add #98 to the final save?

[jgrano]

Final save of design and starting to print based on all feedback.

[Burhan-Q]

Darryl to print for testing

[jgrano]

Body that I printed works great, integrates fine with existing shutoff valve body. Waiting for verification from Darryl

[mechatroniks-git]

John, nice work. Can I go ahead and print the FDM parts on this? should I pull STLs from Fusion? Point me in the right direction, want to make sure I print the right ones. Thanks.

[jgrano]

https://github.com/tetrabiodistributed/project-tetra/blob/master/02_Development/Prototype_release/Alpha/Parts_to_print/P-TET-000019-2.stl

[Burhan-Q]

https://github.com/tetrabiodistributed/project-tetra/blob/master/02_Development/Prototype_release/Alpha/Parts_to_print/P-TET-000019-2.stl

@DHHwangPhD ready for testing, please comment when print has started

[mechatroniks-git]

Part fits knob much better, nut capture is good also. O-ring compression is too much. Need to revise. Currently it is a 2mm o-ring compressed 35%. We should try 10% compression. See https://www.marcorubber.com/o-ring-groove-design-considerations.htm

Also, not sure we can do much about it, but the thin section at the bottom, but as the groove goes deeper, this will be weaker.

[mechatroniks-git]

Reduced o-ring groove ID such that o-ring compression is 10%, not 35%. Should make it easier (possible) to assemble.

Bumped part number embossed on part to P-TET-000019-3

Ready to print & test

[mechatroniks-git]

design updated to -3, ready for review @Burhan-Q

[Burhan-Q]

Part fits knob much better, nut capture is good also. O-ring compression is too much. Need to revise. Currently it is a 2mm o-ring compressed 35%. We should try 10% compression. See https://www.marcorubber.com/o-ring-groove-design-considerations.htm

Also, not sure we can do much about it, but the thin section at the bottom, but as the groove goes deeper, this will be weaker.

I'm seeing the change as 1.90 mm (5% of 2mm o-ring). If this is still okay, then I think this part looks good.

General note for main body vs thru body nut capture dimensions, request was to reduce main body nut capture to 7.1 mm here, but stated above that this size (7.3 mm) was good.

Part fits knob much better, nut capture is good also.

[Burhan-Q]

@jgrano @Judoguy12
Ready for approval for whoever is available. Please self assign this issue if you're able to Approve

[mechatroniks-git]

@Burhan-Q good catch on the oring groove depth. I'm ok to test it with 5% compression on first article

[Burhan-Q]

Latest model milestone
P-TET-000019-3.zip