Well Nuts as paint-friendly blind fasteners

[jdcaples]

Since I have an NCV3, I’m putting this in the NCV3 Write-Ups area.

However it’s possible that T1N owners may find this useful.

I was interested in blind fastener technology and decided to test Well Nuts.

Here are some links.

Supply: http:///www.mcmaster.com ( search for “well nuts”)
Google Images: http://images.google.com/images?hl=en&q=well+nuts&gbv=2
Americans may also find them at Home Depot or Lowes.
(Lowes near my home in Seattle carry the same gizmo under the name "expanding rubber nut.")
I also saw some at Ace Hardware.
Cost: I paid about $0.58 pennies a each from McMaster-Carr. Local hardware stores sell them for anywhere between $0.85 and $1.20 each


Do they work? Yes.

How do I know? I tested it.

What test?

This test: I took some scrap cedar fence-calibre wood, cut it to 16 inches marked and drilled a few holes in it to line up with some factory holes of my Sprinter. I elected an overhead rib for my test.

I put suitable machine screws (for the Well Nuts I purchased) though the wood and then screwed on the Well Nuts. I brought the Well Nut down the threads to touch the wood.

Then positioned the wood and the Well Nuts + machine screws into the vehicle holes.

To my surprise, the holes in the Sprinter lined up with the holes I made in the wood. That's a big deal. I am not what some would say "talented." I am what one woodshop teacher called "a likeable clutz that - nevertheless - should be banned from using tools, for life."

Happy that things lined up, I tightened down the machine screws - expanding the Well Nuts in the holes - until the wood seemed solid.

Tip: If they wiggle around, loosen the machine screws – relaxing the well nut’s compressed rubber - then reapply torsion to get a more snug feel.

I suspect that you can finesse the grip by adjusting the rubber cylinder in this manner.

After the wood seemed pretty resistent to lateral forces (left / right, forward/backward) I attached the gate handle.

Then tragedy struck: I forgot that I needed to test the ability for this contraption to hold something. I took off my belt and grabbed a gallon of water. It worked. The picture's at the end of this posting.


Questions I asked myself:

Did the Well Nut tend to spin in the hole? No, but I was holding wood against gravity, so I may have been applying some pressure to the exterior mating surface.

Why didn't you just drill holes, Jon? Because I didn't want to introduce my Sprinter's paint to any spare metal debris. I live in a moist climate and I fear rust.

Aren't you eventually going to have to drill some holes? Why can't you let me live in denial?

Jon, dont' answer questions with questions. Ok.

A few pictures below. Gotta run.

-Jon


zero.JPG
one.JPG
two.JPG
A Well Nut dangling from the wall (it would have fallen out of the ceiling holes) ready for insertion, waiting for a machine screw to make its life complete.
three.JPG

A gate handle, my belt and a gallon of water, all held up by Well Nuts.

[Douglas Hicks]

Somehow I am picturing the shop class klutz standing in his van, gazing with pride at his belt holding a gallon of water, while his pants are around his ankles.

American van has something similar,but stronger. Those American Van bolts hold the shelf units in both Sprinters. I tried the wellnuts and found they failed. I also tried a similar product used to hold mirrors on GM pick-ups. They also failed.

[rlent]

Originally Posted by Douglas Hicks

Somehow I am picturing the shop class klutz standing in his van, gazing with pride at his belt holding a gallon of water, while his pants are around his ankles.

Heheheheh ........

[jdcaples]

Originally Posted by Douglas Hicks

Somehow I am picturing the shop class klutz standing in his van, gazing with pride at his belt holding a gallon of water, while his pants are around his ankles.

American van has something similar,but stronger. Those American Van bolts hold the shelf units in both Sprinters. I tried the wellnuts and found they failed. I also tried a similar product used to hold mirrors on GM pick-ups. They also failed.

Life's too short to not make fun of oneself occasionally.

Thanks for the notation about strength. I did test it further. I wrapped the water in a plastic bag to prevent drenching the back and I did manage to drive around with that water bouncing around the bumpy streets of Seattle. It remained.

Eventually I wondered how much they could hold, so I gave it a good yank - probably 1/2 or 75 of my 150 lbs. Upon release, two machine screws were bent, and one of the four Well Nuts was sacrificed. They'll work for my needs, but I agree they're probably not appropriate to hold up cabinets.


-Jon

[autostaretx]

... let's see.... 75 lbs pulled them out, and a gallon of water weighs 8 pounds.

So you have created an automatic type-A fire extinguisher, activated by a 9 G crash.
(added advantage: water will be directed towards point of impact)

Excellent!
...now go test it...
--dick

[autostaretx]

Chasing down the Hansonrivet weblink, i see that the 8-32 (B832) Well-Nut you were testing is "rated" for 140 pound tensile strength.

A "good yank" (is that an antonym for a "bad Brit", or a similar measure to a "calibrated Canuck"?) may well put a high impact load on the fastening system.
An 8-32 steel screw has a theoretical tensile strength of 850 pounds, but the stress area is only 0.014 sq inches.. so a -bending- force (as demonstrated) can be far lower.

have fun
--dick (thanks for the web-reference... "Multi-Grip Threaded Inserts" seem to be very similar to Plus-Nuts:
http://www.hansonrivet.com/w67a.htm
)

[jdcaples]

Originally Posted by autostaretx

... let's see.... 75 lbs pulled them out, and a gallon of water weighs 8 pounds.

So you have created an automatic type-A fire extinguisher, activated by a 9 G crash.
(added advantage: water will be directed towards point of impact)

Excellent!
...now go test it...
--dick

Um, no.

I'm strictly theory.

No life forms or Sprinters were harmed - or placed at risk- in the process of creating this write up.

I'm not smart enough to take it to the next, fire-supressing level.

Perhaps someone that works around particle munching monsters, one who is in possession of an actual engineering degree, would take my whimsical notions their maxium potential?

In closing, as my cousin is fond of saying, no lifeforms were harmed during the creation of this message, but a good number of electrons were significantly inconvenienced.

-Jon

[twistyroad]

I've never used wellnuts in automotive applications, but they're commonly used as fasteners for motorcycle windscreens, because they can tolerate a high level of vibration (read: wind buffeting) without coming loose, and they have enough "give" in them that they won't serve as the start point of a crack in the Lexan/plexiglass windscreen.
But I can tell you from personal experience that they have a weakness you haven't mentioned/considered... the rubber will dry out and harden, and ultimately crack, crumble, and disintegrate. How long they last varies, mostly dependent upon how much they're exposed to a hot environment (perhaps on the underside of a roof in the summer sun?), and whether they're artificial rubber (more common) or real rubber (harder to find, but last much longer). When not riding, my motorcycles stay in the garage, but I still have to replace the wellnuts about every four years.
They're great for their intended purpose, but I would NOT use them in a structural application.
Rock

[mean_in_green]

I find Rivnuts work well.

[pugwash]

I used to build accomodations for the offshore industry and used clinch nuts they are similiar to what you have been using but in steel they came in boxes of 500 suitable for in 3mm, 4mm, 5mm and 6mm bolts,from a UK company called Buck & Hickman tools. 'I did a google search and they are online', we often fixed steel cabinets to walls and 100% success rate. type in clinch nut in the search box or I had a quick look for steel panel fixings and other bolts came up we did use ZSUS or ZEUS fastenings but found they had a tendency to break.

hope this is of some help.