QUICK-ACTING KNOBS 1

[drawoh]

Has anyone here used any of these fast acting knobs from Carr Lane? How reliable are they? Would you be comfortable securing equipment on top of a truck with them?

--
JHG

 

[BUGGAR]

I think the question should be would you be comfortable with your child driving behind that load.

 

[drawoh]

BUGGAR,

I have never used one. I have never handled one. I have never hit one with a hammer. I have never poured coffee on one. I have never seen one. That's why I am asking. I am being asked about quick release fasteners, and I can easily and safely implement studs.

--
JHG

 

[3DDave]

Experience with similar items says that there had better be an independent shear path because sideways motion can cause them to release.

 

[JohnRBaker]

Once they've been tightened I would think that that they would be quite safe. After all, you have to tip them at a NOT insignificant angle before they are permitted to 'slip' off.

Now of course this is all predicated on them remaining tight, so if the service environment has big temperature fluctuations and/or vibrations, then I would say avoid using them. But if that's not going to be an issue, then I think they may be a good solution particularly if being able to quickly and completely remove the knobs is highly desirable.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[BUGGAR]

They can wear around their bearing surface at the base, becoming rounded, and can then let go under a slight load relaxation.

Prior experience with similar (hard plastic). Please test them first.

 

[GregLocock]

No.

Grit, dust, vibration, truckers.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[Sparweb]

There are many other choices of threaded fasteners that release quickly and tighten firmly... This one is interesting, but, cast & cut threads? To secure a load on a moving truck, NO.

STF

 

[handleman]

You can get better ones from Misumi that aren't cast... I have used them with great success to hold down jigs/pallets in automated assembly equipment. That said, I would not trust one as far as I could throw it. Well, maybe I would. I could probably throw one about 100 feet or so, and that's about how far I would trust one to secure a load to a truck.

-handleman, CSWP (The new, easy test)

 

[Artisi]

Interesting concept but as a truck load hold-down - not for me, I come from a dog and chain background.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[MikeHalloran]

I've used them on fixtures, where slippage is not usually life-threatening.
They do speed up operations where you have to r&r them a lot.
They hold just fine, if you get them oriented correctly before attempting to tighten them.
If they're just a little cocked when you start tightening, they'll slip off.
Maybe if the extended end seated in a counterbore in a tight fitting thick washer, they would tighten more reliably,
but you'd lose time translating them over a couple of extra pitches.
Even with that modification, ...
No way would I use them to secure a load on a truck.



Mike Halloran
Pembroke Pines, FL, USA

 

[Tmoose]

"on top of a truck "

http://project-jk.com/gallery2/main...2_GALLERYSID=60ca3a4a8034f2f3fa69f8a9d0a8f81a

http://greenracingproject.com/blog/wp-content/uploads/2015/03/photo-31.jpg

https://localtvkstu.files.wordpress.com/2015/06/boat-on-truck-via-scott-2.jpg

http://www.mastercraft.com/teamtalk/attachment.php?attachmentid=101207&stc=1&d=1379361758

 

[btrueblood]

drawoh,

Can you re-engineer your box to include toggle clamps that will catch on a mounted loop/catch that is mounted to the truck? Especially the double-locking style of toggle clamp.

http://www.mcmaster.com/#toggle-clamps/=14jcl7e

 

[JohnRBaker]

How about something like a 'Hood Pin'?

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[Compositepro]

I have used these knobs and they work great for many things. However, most of the thread area has been milled away so I would guess that they only have about 25% of the strength of a full nut. I would not rely on them for safety critical holding applications.

 

[drawoh]

MikeHalloran,

Thanks. My clearance holes are for M6, so drilling studs and using pins is not an option. My original plan was a threaded, knurled knob, large enough to ensure adequate torque. It looks like I will stick with it.

--
JHG

 

[BUGGAR]

Anyway you can work in the "Super Snake" wording on you knobs like shown on Mr. Baker's post.

 

[drawoh]

BUGGAR,

I cannot see the picture here at work. I saw it at home, so I know it is there.

This is an instrument mounted on a platform on the back of a truck, and I don't see how we could work up a snake theme. Do you think a racing stripe would improve the performance of quick release nuts?

--
JHG

 

[btrueblood]

Clearly. Flames would work also.

 

[Sparweb]

You can also make the instrument look 50% lighter if you apply decals on the sides that look like carbon-fiber.


STF