Anyone tried these 'Blind Rivet Bolts'?

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cheapracer

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Saw these, wondering if anyone has used them, or similar, or knows where to get them besides the French manufacturer of them ..

https://www.clufix.com/

The Leankeasy blind rivet bolt from Clufix, Cluses, France, crimps the nut as a screw is turned to lock two metal sheets or plastic parts together. This makes installation a one-step process and only a single fastening component is needed. Installation requires no special equipment. By reducing the number of parts and assembly steps, installation costs are 35% lower than with traditional blind rivets.

screw you.jpg
 

cluttonfred

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Interesting, but from the diagram the holes in the two sheets are different sizes and I don't see how they can claim that it reduces assembly time or parts count vs. blind rivets. Am I missing something?
 

cheapracer

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Ashley, think about it, if it's just 'throw a bolt in the drill attachment', stick it in the hole and screw, it might be faster than a blind rivet as you have the secondary operation of clearing the rivet tail out everytime - and they don't always come out without a hassle.

I don't think the that time factor is of huge concern to our homebuilds though, I was more interested in the strength factor.
 

Vigilant1

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It looks to do the same thing as widely available rivnuts, right?
https://www.boellhoff.com/us-en/products-and-services/special-fasteners/blind-rivet-nuts-rivnut.php
1) Drill a one-size hole through one or more sheets
2) Set the rivet/nut. This hold the sheets together (if more than one) and provides a nut at the back side, the front side has a small flanged portion around the hole that clamps the rivnut to the one (or more) underlying sheets, holding them together.
3) The top sheet has a hole drilled large enough that the flanged portion of the rivnut can fit entirely inside it.
4) The "screw /bolt" portion of the fastener holds the top sheet to the underlying sheets. Various head types available--countersunk, hex, etc.

The selling point is removability of the top sheet (which is very handy--inspection/access panels, brackets, cowlings, etc). I don't see it as being a faster way to join two or more sheets, though.

Anyway, if the product in the OP is the same as a rivnut, you don't have to go to France to get them. They are a commodity item that is widely available.
 
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cheapracer

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It looks to do the same thing as widely available rivnuts, right?
I've used Rivnuts (by brand) in the past, didn't like them, found they often spun in the hole when tightening the bolt up, backed up by a worker who fitted them to Volvo trucks, he cursed how many times he had to remove one's that spun.

The OP type are a single operation, there's your major difference.
 

TFF

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I assume time savings is bolt is also what sets the threads. No pulling tool. Drop threaded part in its hole, put covering part over, drop bolt in and tighten until set. Assembly line style zipping them in. Nothing worse than a loose rivnut.
 

Mad MAC

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I've used Rivnuts (by brand) in the past, didn't like them, found they often spun in the hole when tightening the bolt up
You can get keyed Riv nuts (NAS1329 would the aerospace spec).

My worry with the Leankeasy blind rivet bolt is what would the bolt shoulder go to do the surface of the skin, unless one uses a washer if that is possible, plus the usual issues of acceptable torque range for setting the nut.
 

Mad MAC

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In theory, they work. Not so in Florida, though.


BJC
Not really unexpected, but do suspect that CNC cut keyed holes and using fasteners with lower thread friction (plus possibly paying close attention to the thread tolerances) may move the population mean to ones benefit .
 

BoKu

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Hard pass. If I was making mass transit buses, railroad passenger coaches, or farm implements, these might actually be economical. I can't see that they'd do anything for airplanes that rivets or AN bolts don't do better, faster, and stronger.
 

BBerson

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Should be stronger than pop rivets for gussets on square tube where it needs to be blind.
What is the smallest hole size?
I can see drilling a 3/16" pilot hole then stroking the hole with a tapered square or hex file to make sure it won't spin.

Yeah, I want some.
 

cheapracer

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Should be stronger than pop rivets for gussets on square tube where it needs to be blind.
Yeah, I want some.
Yup, blind tube was what I was thinking mainly.




Why would these spin less than a Rivnut?
Because a Rivnut is squeezed in, and then the bolt is put in. You don't know if it's going to give or not, whereas these rely on gripping to be inserted with the bolt in a single action.

If it fails to grip, it also then fails to collapse and you can remove it to see what the problem is.

After seeing them though, I then saw Rivnut have a hex version, apparently the "original" that of course wn't spin. Hex holes are "drilled" with a laser in my case.


. Drop threaded part in its hole, put covering part over, drop bolt in and tighten until set. .
No, it would appear they come as one unit, i.e. the bolt is already in the collapsable nut when you recieve it, just drop it in the hole(s) and zap it.

It would defeat the purpose of speed on manufacturing if a worker had to stand there and partly thread a bolt into the nut every time.

Mathew above was concerned about needing 2 different sized holes for the operation.
 

Dan Thomas

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Yup, blind tube was what I was thinking mainly.






Because a Rivnut is squeezed in, and then the bolt is put in. You don't know if it's going to give or not, whereas these rely on gripping to be inserted with the bolt in a single action.

If it fails to grip, it also then fails to collapse and you can remove it to see what the problem is.

After seeing them though, I then saw Rivnut have a hex version, apparently the "original" that of course wn't spin. Hex holes are "drilled" with a laser in my case.




No, it would appear they come as one unit, i.e. the bolt is already in the collapsable nut when you recieve it, just drop it in the hole(s) and zap it.

It would defeat the purpose of speed on manufacturing if a worker had to stand there and partly thread a bolt into the nut every time.

Mathew above was concerned about needing 2 different sized holes for the operation.
If it spun when partially set, you wouldn't be pulling it out to see what the problem was. You'd be fighting with it, trying to hold that thin head while drilling it out, just like I have with dozens of spun rivnuts over the years.

Use a rivnut, and put a little epoxy or Loctite on it when you insert it, and use the rivnut tool. It will stay put better. The keyed versions require a notch in the hole, which I see as a stress riser and could lead to cracking.

And as far as setting this bolt-type fastener, I don't see it as saving any money or time at all. It will want to spin when the thread loads start building. There's way more friction in the threads than there is between the head and workpiece.

If you want strong pop rivets, use CherryMax rivets. They make the common Pop rivet look horribly weak. But you'll pay a lot more for them, too.
 
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