Hollow Bolt Torque Specification

While I've come up with a variety of sources for torque tables for both English and Metric bolts, I've run into a problem with finding a good torque setting for my uninsulated binding post for grounding. It's this one, which is made of nickel coated brass and is hollow to accept a banana jack:

https://cinchconnectivity.com/OA_HTML/ibeCCtpItmDspRte.jsp?sitex=10020:22372:US&item=4252201

https://octopart.com/111-2223-001-emerson+network+power+-+johnson-29988

Its "datasheet" is sparse and blithely omits maximum torque for the nut. As it turns out, torquing it to 77 inch-lbs as you would for a brass 1/4-32 bolt simply pulls this thing apart!

http://www.engineersedge.com/torque_table_sae.htm

There are a variety of similar uninsulated banana jacks or binding posts which also don't have mounting torque specified.

http://www.grayhill.com/assets/1/7/pushpoststerm.pdf
http://keyelco.com/userAssets/file/M65p111.pdfhttps://cinchconnectivity.com/OA_MEDIA/specs/pi-108-0740-001.pdf
http://www.pomonaelectronics.com/pdf/d3267_1_01.pdf
http://www.caltestelectronics.com/images/attachments/CT2220_drawing.pdf
http://www.caltestelectronics.com/images/attachments/CT2232_drawing.pdf

Torque is specified for all kinds of plastic-bodied banana jacks, but those values are going to be lower than what I'd want to use because I want this thing to be given the best possible connection to the front panel to ensure good grounding.

This catalog contains one tightening torque for a panel mount banana jack. Its 120 N*cm which translates to about 10 inch-lbs, which is interesting because this is for a plastic mounting body. https://www.radiall.com/media/wysiwyg/BananaPlugs_catalog_D7M00CE_1_ed_2011_.pdf

This datasheet seems to be useless, it specified a torque but it seems to be for the little terminal screw on the back rather than the body. It's also a shockingly low torque spec. http://www.pomonaelectronics.com/pdf/d72930_002.pdf

There is one torque spec in this PDF of three different parts' datasheets. It's 6 inch-lbs, but it's clearly for a plastic-bodied part.
https://www.egr.msu.edu/eceshop/Parts_Inventory/datasheets/insulated%20binding%20post.pdf

I looked around again for online torque calculators, but was unable to find one that produced results for anything but standard bolts.

This seems to be a pretty nice torque calculator, and it even had a "hollow screw" option but for some reason that option didn't work, the tool simply resets. http://www.online-iso-calculator.com/online-bolt-torque-calculator-metric-vdi-2330/us/index.php

Here is another nice torque calculator, but it didn't seem to have a "hollow screw" option. It does allow you to put in your own tensile strength, and I played around with putting tensile strength for brass into this one but still got ridiculously high torque specs: http://www.futek.com/boltcalc.aspx

Here is a cute online calculator for converting between Nm and inch-lbs: http://www.numberfactory.com/nf_torque.html

I found several references to a "NASA Fastener Design Manual" NASA-RP-1228. However even NASA sites like this one had dead links to it: http://www.grc.nasa.gov/WWW/StructuresMaterials/TribMech/publications.html

I did eventually find a copy of NASA-RP-1228 and it's very nice but largely filled with theory with nothing I can just directly reference for this problem

I finally had an idea that a similar product that would be more likely to have a torque spec would be panel mount BNC connectors. It was still hard to find something, and the information that I found had to be derated because BNC connectors are usually steel rather than brass and a wider diameter.

Here is a page all about BNC connectors with unsourced recommendations for jam nut torques (below the section for interconnect torques, which are a much bigger deal for BNC and other RF connectors). For 1/4-inch it has an implausibly low 3-5 inch lbs recommended. https://www.microwaves101.com/encyclopedias/connector-torque

This datasheet had an extremely high 25 inch-lbs listed for jam nut maximum mounting torque. Presumably I could apply some derating to that: http://www1.futureelectronics.com/doc/TYCO%20ELECTRONICS/5227169-8.pdf

I eventually also had the brainstorm that toggle switches are also panel mount, hollow with jam nuts, and about the size of my insulating binding post. Amazingly, it was still difficult to find a switch datasheet that had a spec for a mounting nut torque.

The best source that I found for switches was the NKK datasheet for their M series (minature) toggle switches. Its spec is still a bit murky however, it lists an incredible 26 inch-lbs for "large bushing" switches, and two specs, 13 and 6 inch-lbs for double nut vs single nut (not completely sure what that even means but I think it's whether there is a nut on the shaft in the back or if only a front nut is used). http://2t70un3m1d9z1kztamkdrd38.wpengine.netdna-cdn.com/wp-content/uploads/2016/02/MtogglesBushing.pdf

NKK's extremely well organized site with other links is here: http://www.nkkswitches.com/products/toggle/#jump-post-103

Bolt Torque tables

Because my assembly instructions have to be very precise, I needed to find actual torque values to put in for every bolt called out in the parts lists. I also expected that there should be some restrictions on the amount of torque one should apply to screws attaching circuit boards to standoffs. Oddly, searching on torque values for circuit board assemblies produced no useful results. It seems that a few other people have had the same assumption, and when they asked the question on forums nobody else thought the question made any sense. Eventually, I found one set of tables, adapted from a Japanese standard, which listed torque values for "electronic assemblies" which seem to be simply half the standard torque values. Here is the link to that table. This table is neat because in addition to the standard and halved values, it lists tighter values for high strength bolts. Also note that aluminum bolts/threads are listed as requiring 0.5 of the standard torque:

https://mdmetric.com/tech/Standard_tightening_torque.pdf

Note that the above table give torques in Newton-meters, logically enough. To convert that to inch lbs, there are sites that have calculators like the following:

http://www.unitconversion.org/energy/newton-meters-to-inch-pounds-conversion.html

That table is from something called the "Tohnichi Torque Handbook" which comes up well in Google searches on its own. Those values are for metric bolts and screws only, however. For English bolts, I got more google hits, strangely:

Here is the one I've been using mostly, because it goes all the way down to #4 screws and gives the values in inch lbs. However, this is just a car enthusiast's blog and doesn't credit the source of the table so I should probably find a better link: http://tr6.danielsonfamily.org/TAStripTest.htm

This table references SAE values, but doesn't apply to anything smaller than 1/4-inch bolts. This is the issue I encountered for most Google hits for English bolt torques: http://www.engineershandbook.com/Tables/torque.htm

However, it looks like another page on the same site does have the smaller sizes, and also lists torques for aluminum: http://www.engineershandbook.com/Tables/torque3.htm

This presentation has a nice table on page 9 which goes all the way down to 4-40, and an appendix that shows how to derive values for yourself using formulae: http://fp.optics.arizona.edu/optomech/Fall14/Notes/18%20Fasteners.pdf