7/16-20 x 1.1/4" SHFH Bolts


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Just ran across an empty bin that wound up in my department marked as such labeled for the bolts to be stored within it.

Fascinating what they meant by it.. Took me a little while in sharing with my department the lables of what specific bolt was to be stored in the bin and in laughing. But also concerned in that multipitle times a week I have to explain to people bolt/rod stock in size and next concept threads per inch or mm. O'gee, that is what it means.

What bolt was specifically to be stored in this bin? What is given the understanding of bolts could have this bin otherwise been labelled accurately? 7/16-20 x 1.1/4" SHFH as labeled.

There is two correct choices dependant on who labeled it in mis-understanding overall of bolts.
Those who know or can troubleshoot this question should wait in answering. PM instead. SHFH part type wait a while on it a day for advice. This is an educational forum... terms and details. Hints ok but don't get too expressessive in the challenge.
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First hint.

SHCS = Socket Head Cap Screw.
SHFHS / SHFH = Socket Head Flat Head Screw.

This person understood the "SHFH" description as told, the initials in how to describe the bolts in labeling. Someone told this person enough to label the bin but not enough to educate or properly mark it. Also 20 threads per inch was correct in bonus help here. Still a question to answer by students. Very important and common "tech" people confuse - thus the asking that those who know don't just answer. You can PM or wait.
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I’m not a student but I truly have no idea what this screw is for.
Good challenge than. As above "I have to explain to people bolt/rod stock in size and next concept threads per inch or mm. O'gee," - above.

What am I explaining is a slap upside the head on what, who labeled the bin didn't get. And the superviser approved of the labeling in also not getting it about bolts how it was labeled. This is a hard one given a SHFH screw. What if the question were about a hex head bolt? (hint.)

Very educational once the appiffony. Other Pro's chime similar if you don't see the answer chime in. Or PM for the rest of the week if you now get it.

7/16-20 I find as a surprise to me, does exist in a SHFH screw https://www.mcmaster.com/products/screws/thread-size~7-16-20/flat-head-screws~/. This was not the bolt described in the mystery bin and exists nowere in the shop... This is not the answer to the question.
Jay T figured it out. No doubt he has run into this similar problem of bolts requested before. It's a semi-common bolt question seemingly in often for me.

Bin was believed to come from the LED dpt. they have their own stashes of bolts or do dump and run's on the shop bolt wall in either putting stuff away wrong, or just leaving it on the floor or any space available short of putting it away properly. As with tour tech people... same problem but they don't have 18" bins. It's department has this size of bin in use and probably some bolt they installed for a clamp bracket commonly but no longer use thus the me getting the empty bin. What might have remained in it was hopefully restocked properly.

One of that department's workers today came to me looking for some wide aluminum wing nuts to replace a missing one on a square Cheseborough, with the approval of his Department Manager. Just need some replacement wing nuts....

I asked his tech person if it was 1/2-13, M12-1.75, 1/2-12 wing nut he wanted (1/2-12 is "old English standard, the origional bolt used on Cheseboroughs from China.) What thread class and grade of aluminum he wanted the wing nut to be? Than on the demo Square Cheseborough he brought with so as to match the wing nut to... screwed it to it's end point in able to open or remove the wing nut. The Eye bolt had a deformed thread on it in demonstration which prevented the wing nut from coming off. I asked the tech person, how given the deformed threads do you intend to install a new wing nut on the eye bolt. More important what will be the load rating of this Square Cheseborough once you screw a wing nut onto the bolt past the deformed threads? For these reasons we do not ever put a wing nut onto a Cheseborough, instead we replace the assembly with supervision as to how to and when not to do so. Specific training on doing so.
There is a box of replacement Wing Screw assemblies next to the arbor press. He wisely dropped the bad one into the pile of bad ones, included rusted ones called into question of if I would use this over someone's head.... an assistant needed to ask about in safe to use. At least that person has potential in learning. At some point, LED department will run out of clamps and either need to fix or get more purchased. Fine with that result.
Another common problem in training. At some point, never good on a timeline training is good. Or throw more money at it... Rock and Roll. Time third part of the pyramid of getting stuff done.

Seems so simple, just a wing nut... replace and clamp over the audience or talent's head... fixed. Educating the next generation, vs. McDonalds pays really well these days.

Sorry for the off topic in related.. Can get this labeling problem question.
So.. what was the bolt actually supposed to be labeled? I still don't get it?
Ah' thanks for the reminder. Time is indeed up.

For some reason it's common to define a bolt in various un-educated ways.

So... 7/16-20 x 1.1/4" SHFH screw labeled bin - for storage of those bolts. SHFH means (hex) socket head the driver as opposed to something like phillips head. So the SH is a hex driven bolt. FH is the type of bolt - see above. Common letters given for a type of bolt....

(No! that's not what the problem is in not understanding the funny part of this!)

Young in-experienced technicians often don't get or even half get what they learn. So as often... I need a 3/4" bolt... You need a what? Turns out that is for some reason misunderstood requesting wrench size for the bolt, in this case 1/2-13 they need. Funny how the reverse is also true in wanting say a 1/2" socket for a 1/2-13 bolt. Just so confusing...

So... 7/16-20 x 1.1/4" SHFH screws, do we get the misunderstanding in labeling about the first part of the label? This is a even flat head bolt using a 7/16" wrench in defining what's in the bin. Approve of by the department manager... (lower case letters intended.)

Ah' but it's a flat head screw... Defined as a 1/4-20x1.1/4" Socket Head Flat Head Screw... it doesn't have a hex top to it. There is the interesting and kind of funny mis-labeling part of the problem. It's abstract.. someone who doesn't understand bolts... still focused on wrench size for what nut to use with the bolt labeled it that way. This as opposed to even what hex key driver for the bolt. Someone had a theory of what wrench drives the bolt.. never had a slap upside the head moment when approching even at least the shop's bolt wall in getting more. Or dpt. manager's training before or after.

So the final answer was acceptable for two solutions to the labeling...

First is it a 1/4-20 x 1.1/4" Socket Head Flat Head bolt, or a 1/4-20 x 1.1/2" Socket Head Flat Head Screw. One would think the total length of a flat head screw would be measured... But a question about the un-trained individual marking the found bin... Did on Flat head screw this person by chance mark it properlly? Or did they get intercepted at some point so as to measure the bolt from under the head of it - like a hex bolt? Oh'... in not understanding anything else... you measure the length of a hex bolt from under it's head. Not getting the concept of the fastener length. This and general understanding of bolts.

What was on the bin marked... funny but also sad.

My department laughed about the labeling of the parts bin... TBD the rest.

The ah' I didn't get it yet in posting I hope helps seeing what is coming to you. It's becomming common to me.
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that's an alien term to me.... New QOTD!

Was the above 7/16" wrench defination as to a flat head screw in sizing entertaining for anyone, as for my department? Ah' I get it.
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Well sometimes I go looking for the SHTF bolt. That's one visually 2 sizes bigger than you intuitively know will do the job, but you cant take any chances.
A "Whitworth 1/2" wrench" is a wrench which fit the head of a 1/2" "major diameter" Whitworth bolt. And, Whitworth threads use a 55 deg. tooth angle vs. the usual 60 deg. But I suppose this is all academic now, as the Brits are probably all metric now.
Having gone through a number of thread sizes and pitches and angles we are indeed now pretty much settled on metric sizes. No more BA BSW BSF etc confusion.

Edit: we've also had BSP pipe threads and I'm sure I've seen American coarse and fine too.
A project manager came over to me today to borrow wrenches. Moving lights installed the clamps with an impact driver and they were not movable even with fiber washers between clamps. A fiber washer is a fiber washer which ensures tension of bolt but kind of a frictionless washer to allow some movement. I don't remember loaning that department a impact driver but possible.

More important I was shown the clamp assembly. Ah' I understand how we are out of the limited supply I intentionally supply of the "last resort nut" came up short yesterday.... Moving Lights Dpt. got lazy or not caring. They had some brackets with plenty of room for long bolts and proper nylock nuts, but chose for some reason smaller bolts and using up all the thin nylock nuts. Really have to have further discussions with both LED and Moving Lights dpt's.

I told the project manager with a problem with his clamps too tight to swivel the fixture clamps to the truss to send them all back to Moving lights instead of trying to make work. In the end... he went with what was sent, no time to fix this and a short hung and duration show. Wrong but ok, you are now responsible for it. What he showed me was a gr.8 thin Nylock nut in use. Certainly safer than a grade 2.

Still though failure in shop. Moving lights dpt. could have had a longer bolt with proper nylock nut... but they didn't. This caused another tour to ask for the I keep low in stock them in also not really needing them problem earlier in the week. Moving Lights produced likely 100 clamps with an assembly which was for some un-known reason agaist current shop policy in using proper hardware. This prevented another show from using improper hardware.

Gonna have to have to have a discussion with upper Management in just banning the thin nylock nuts for use - a new policy of a nut of last resort only, and only one time I have found it's need in other options including side lock nuts well in stock and rarely used. Thin nylock nuts are too commonly used out of laziness and not understanding why not to use them. As with overstock of fiber washers, forged wing nuts.. add these nuts to my cage of not normal access to, or access in if I get low in stock I will know about it.
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Well, 7/16-20 is a fairly common bolt-screw designator, though whether that would default to UNC (like a 1/4-20) or UNF (like a 5/8-27 mic stand thread) I don't know off hand, and it should probably say -- though in most cases a given size is only *available* in one thread pitch, so it may not matter... Presumably the mis-written 1-1/4" is the length of the bolt. I wasn't familliar with the type abbreviator, but clearly that's pretty standard too...

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