Rivnut Tool
 

My team has been using rivnuts for the past couple years and we love them. I was wondering if any other teams use them and if so what tool do they use to put them in. We currently use a hand powered rivnut gun https://www.grainger.com/product/POP...AS01?$smthumb$

It works great but is hard on your hands after a while and prone to lots of error. Has anyone used an power tool rivnut gun?

Re: Rivnut Tool
 

Think about what the rivnut is doing, and how you can make your own tool.

Drill a close fit clearance hole for the size you are using in a piece of thicker steel. Put a bolt through the hole, screw the rivnut on the other side so it's tight. Place the rivnut in the mounting hole where you want it and use a powered drill to turn the bolt. Tightening the bolt will pull the rivnut bending portion tight to the mounting hole.

Re: Rivnut Tool
 

If we need to put more than just a few, we use a pneumatic gun.

Re: Rivnut Tool
 

We've always used a wrench-driven tool, McMaster PN 96349A380.

Re: Rivnut Tool
 

where did you get your pneumatic gun from and you have any idea on the cost. All the ones i can find are very expensive

Re: Rivnut Tool
 

I did not know these were a thing. But let me tell you they have made my day and I fully intend to use them where I can now that I know about them. So thank you guys.:D

Re: Rivnut Tool
 

One of the ways we've used rivet nuts recently is to fasten our bumper frame to the chassis. On opposite sides, we have four 1/4-20 bolts spanning through the c-channel, 2x1x0.1 tube spacers, and into the threaded rivet nut.

Here is a top view
Here is a better angle

We also use the hand tool. We keep all of our rivet nuts in a special box with the gun.

Re: Rivnut Tool
 

Thanks for sharing! We have purchased a possibly identical tool and some 10-32 inserts from Hanson rivet. Before we use it, I'd like to ask a few questions.

What sort of error? How can we eliminate or at least reduce this error?

The tool we purchased pulls on the mandrel/bolt linearly, not through torque applied to the threads on the insert. Does pulling it this way result in a good set, or does the buckled part of the wall tend to twist under the torque?

We purchased steel inserts. Has anyone used the aluminum ones, and if so, what have you used them for, and how have they held up? Using a threaded aluminum fastener to secure a chassis or mount a manipulator sounds like a stretch.

Finally, the tool we have has several adjustments in order to fit the specific insert being used, particularly the mandrel extension distance. As we have only purchased a single size insert so far, this should not be an issue, but if you use multiple sizes, how successful have you been at getting students to do the adjustments whenever they change from one size to another?

Edit (addition):

Are the c-channel and tube spacers part of the bumper? How about the corner brackets?

We will also have a box just for the riveter, inserts, and the less-common sized drill bits needed for these inserts.

Re: Rivnut Tool
 

Always wanted to use Rivnuts and found this tool recently, thoughts?

Re: Rivnut Tool
 

It's tough to tell from the picture, but it doesn't look nearly as sturdy as the one I linked above. The reviews on Amazon appear to support this - even the best review I read (****0) provided rather weak, qualified praise for the tool.

Re: Rivnut Tool
 

[quote=GeeTwo;1622947]Thanks for sharing! We have purchased a possibly identical tool and some 10-32 inserts from Hanson rivet. Before we use it, I'd like to ask a few questions.



What sort of error? How can we eliminate or at least reduce this error?



The error we have is it takes a lot of hand/arm strength to set them this causes two problems.
1) They do not get properly set
2) if they do get properly they rarely are set perpendicular to the hole. This is due to them just struggling to get them set

we ended up buying a air rivnut gun. Once we test it some more i will let everyone know how it worked out

Re: Rivnut Tool
 

We use rivnuts a bit, and use both aluminum and steel rivnuts. Aluminum ones are easy to install with a manual tool, and easier to replace than steel rivnuts. Steel ones appear to be a bit stronger than aluminum ones, obviously, but sizing the grip length properly keeps installation effort down.

Where it makes sense to, we use a clinch/PEM nut. They can be installed with an impact driver and a bolt, a machine vise, a press, or even a hammer if you're really hard-up (not recommended, but it works...). They are ~1/2 the cost of a rivnut and leave the clamping face of the part nice and flat. Their only real downsides are that they can't effectively be installed into some blind-hole applications such as the middle of a long tube, and require a tighter hole diameter tolerance than rivnuts.

My point is that if you're using rivnuts already it's only a small leap to get into PEM nuts which area cheaper, stronger, and offer different low-effort installation options without the need for any specialized tooling. We use both on our robots.

Here's a shot of our 2015 robot where you can see the use of a few steel rivnuts to anchor a transmission (the rivnut head fit nicely inside the hex relief on the transmission housing) and PEM nuts on the chassis brackets. Steel rivnuts worked well for the transmissions: strong enough, nice thread lead-in, plenty of back-side spacing to fit them, not too many to install, and installed into a plasma-cut and post-machined plate (loose-ish tolerances). The PEM nuts worked brilliantly on the brackets: short enough to fit together, installed two at a time in a machine vise, loads of strength.



In our 2016 our ransmissions were thru-bolted because that made more sense, axle bearings were retained with PEM nuts because of their low profile, the bellypan was anchored with aluminum rivnuts which were strong enough and super-easy to install, and the shoulder tube (that provided a majority of the chassis strength) was anchored to the chassis with 6x PEM-nut fasteners per side.

Re: Rivnut Tool
 

I do not recommended this tool. I have owned one of that construction and I hate it:mad: . All of that style at work, that includes the 4-6 that work buys a year, the round shaft comes loose over time and is frustrating to use. The tool from hansen is much better.

Re: Rivnut Tool
 

+1 for the PEM captive nuts. I use a lot of broach style and they are great. You can buy them from McMaster-Carr. https://www.mcmaster.com/#captive-nuts/=15l08yk

If you need large quantity I'd recommend S.W. Anderson http://www.swaco.com/ They can supply bulk bags for a fraction of McMaster. ;)

For setting steel rivnuts I like the LEM tool. I have a set from #6 to 1/4. I haven't tried their spiral action speed header but it looks interesting. I've never set captive nuts with my LEM tool but it would likely work. http://www.lemtools.com/tools.php

Re: Rivnut Tool
 

For the benefit of any who are considering whether to invest in trying rivnuts, here's my experience so far (first order received a few days ago).

I ordered the PNT-110 and a bag of SKL10-32-130 STEEL THIN-NUTs from Hanson Rivets. The web page for the inserts (rivnuts) specified a "grip range" of 0.02" to 0.13". As our primary use case is with 1/8" (0.0125") aluminum, and the secondary case is with thinner aluminum or steel, this seemed to be a minimal investment (less than $100) for a tool and a couple hundred inserts. While doing my Christmas shopping, I picked up a couple of 19/64" drill bits at Lowe's.

Saturday morning (yes, Christmas Eve, and my son's birthday), I drilled a hole in a piece of 1/8" aluminum bar and tried to set a rivnut in it. I tweaked the nose piece and used arm strength as well as hands, and even tried using the setter as a wrench on the threads, but I could not seem to get the insert to properly set. The insert seemed slightly swollen, but not set as a proper "rivet". For details, see the image, particularly the rivnut at the top, second from the right.

This morning (26 Dec), I had a bit of time to try a few things. My intention was to do a "pullout" test but this morning I decided to try a couple of other things first. I put an insert on the tool, and tried to set it in air. I am happy to report that this takes no more hand strength than a 3/8" rivet. The results are in the picture, third from right.

Then, I tried setting one of these rivnuts in 1/16" aluminum. I had a scrap of plywood edge channel handy, and the result is shown in the image at the far left.

I then did a few measurements of compressed and uncompressed inserts, and I am convinced that a '.130"' nut is only good for 1/8", or possibly 3/16" of material. I have ordered some rivnuts that support up to .225" thick, which should work quite well in 1/8" aluminum. 'll post some upgrades as I learn more.

Re: Rivnut Tool
 

I'd like to hear the results of the pullout test on the 1/8" bar where you don't think the nut really set well. It looks like it expanded enough to keep it from pulling out.

Thanks for giving up your holiday for Science!

Re: Rivnut Tool
 

I have extensive experience with rivnuts from one of my former lives as an instrumentation installer. They work great with proper installation and care, but I have always been reluctant to introduce them to our FRC team because of this one problem-

If you ever manage to break one loose in a blind hole it can be a real bear to get the screw out of the hole.

The odds of this happening increase as the odds of incorrect installation increases. When I finally broke down last season and introduced them (our chassis design last year made our bumpers hard to attach/detach without them) I trained a special crew to use them and I demonstrated the spin-out problem and how to avoid it. It requires a combination of correct installation of the proper size and avoiding over-torquing the fasteners (I find that often teenage boys don't know their own strength!).

Re: Rivnut Tool
 

We have used riv-nuts also called nut-certs (or nut-serts) on 1058 for years. Really helps with fast repairs in the pit!

Step one is get the right tool. We have one similar to this which works MUCH better than the ones that look like a pop-rivet gun: https://www.amazon.com/Astro-1442-Th.../dp/B003TODXQW

Step two is to make sure you have the correct size drill bit. These things are sensitive to hole size so we double check we are using the correct drill every time.

As others have mentioned installation and placement is critical. We almost always have mentor supervision/help when installing any riv-nuts. They are also prone to under and over torquing so we usually teach a few students how to do it properly and supervise closely, or have a mentor install if necessary (with student help of course.) It helps to do some testing on a scrap piece to make sure your tool adjustments are correct.

We have run into situations where they come loose due to install error or just unexpected load and have had success drilling them out, although it's not fun. I would not recommend using loctite on the hardware you're placing in them, and if you do, very sparingly.

I would be interested in a part number or link to a pneumatic tool for installing these. We use a pneumatic pop-rivet gun and it's awesome.

Re: Rivnut Tool
 

I vastly prefer riv-nuts to PEM nuts. PEM nuts have an awful tendency to fall out if mishandled, and because of that I don't really trust them. Once a riv-nut is properly installed, it has a much harder time coming lose. This is just my experience - both solutions are valid. But I don't think PEM nuts are almost ever preferable for me.

Re: Rivnut Tool
 

Ok,

Having never used a rivnut before, I started looking on youtube and came across this. https://youtu.be/3Og-tHIR_0I?t=66

For those of you that have rivnut experience, what are the cons of using this method?

Time. Takes a while to do that method. Also the chance of pulling the threads out of the nut is greater.

If only doing a few no big deal.

Re: Rivnut Tool
 

Installation is time consuming and rather annoying. Anything larger than a #10 rivnut takes some considerable muscle and/or the use of a cheater bar(s).

Re: Rivnut Tool
 

Does this work for the non-self aligning rivet nuts?

Re: Rivnut Tool
 

Initial results of rivnut pullout testing: (Due to budget constraints, only doing 10-32 steel thin-wall large flange inserts this year; if we're happy with the results, we'll expand our options next year).

I drilled a 19/64" hole using a drill press and inserted an SKL 10-32-130 steel thin nut with large flange into each of three pieces of aluminium:

• 3/4" x 1/8" bar (Ace Hardware, looks like 6061, pictured above)
• 0.1" wall Vex 1"x1" tubing (I used a factory hole as a pilot)
• ~1/16" wall channel (sold as 1/2" plywood edging, also pictured)

I then centered a 1/2" hex nut over the rivnut (large enough hole for the rivet to pass freely), added three steel 1/16" thick fender washers, and inserted a 1" stainless 10-32 cap screw (allen drive). I did not have a 3/8" to 1/4" adapter handy, so I could not use my torque wrench, so I used my shortest 1/4" ratchet driver. In each case, I tightened with my index finger and thumb against the adapter socket. In each case, I was using roughly the same amount of torque (to within perhaps 50%) at failure. I shall repeat these tests with an adapter so I can measure torque, and with the longer rivnuts in coming days.

Each setup reached normal (tee-handle) torque with no noticeable deformation or stress relief (that is, yielding or breakage) of any part. On applying additional torque to failure, each case had a somewhat different failure mode. Consult the attached image for clarification.

1/8" bar - the bar did not noticeably deform on a large scale, but the small crimped area of the rivnut reamed its way through the aluminum to a depth of about 0.1" (I was able to put the versaframe tubing wall between the stock and rivet flange with no difficulty) when the machine screw sheared at the head end of the threads. Because the failure was through reaming not bending, I expect that if the force had not been applied normally to the surface, far less force would have been required to pull the insert from the material. I definitely intend that we shall use the longer .225 rivets for aluminum of this thickness. In steel, it is entirely possible that the stock would have held the rivnut to a rather greater pull out force.

0.1" Vex tubing: The crimped area of the rivnut was adequate to hold in the aluminum. However, the wall of the tubing was deformed (volcano style) until the hole was large enough for the insert to be pulled completely clear of the tubing. It appears that a longer rivnut would provide minimal additional capacity, though I shall test this when the longer inserts arrive.

1/16" plywood edging: The aluminum yielded "volcano style" to a height of 1/16" on one side and 7/64" on the other, then the machine screw broke at the top of the treads on the insert, presumably from the bending torque.

Curiously, the VF thick wall tubing deformed much farther than the hardware store grade aluminum bar and plywood edging.

Edit/Addition:
I will add testing this method (with 10-32 thin wall steel inserts) to my next round of tests. It seems to me that you can get better torque with hex head bolts 1/4"-20 and larger than with any normal #12 and smaller heads. I am also concerned that applying torque to the threaded part of the insert during the crimp might result in a weaker/twisted crimp.

Re: Rivnut Tool
 

Not to get too off-topic, but as someone who had never even heard of Rivnuts before seeing this thread, I'm curious... What are the actual benefits of using a Rivnut? Most of the application examples I've seen so far look like it would have been far simpler and faster to just use a regular bolt+locknut.
You don't appear to be saving space since the rivnuts still stick out, and for that matter the rivnuts also appear to create an additional space on the front side of the material that wouldn't have otherwise been there.

Am I missing something here? :confused:

Re: Rivnut Tool
 

The way I understand it, the point is that the nut stays there when you remove the bolt, so it's better if the nut would be in a hard to reach position. Essentially, it lets you tap a threaded hole into a piece of sheet metal that would otherwise be too thin to tap.

My team has used rivnuts a few times in the past. This year we used them to attach our main breaker because the frame member we wanted to attach it to was surrounded by other components so we couldn't get a wrench behind it to hold a nut. There was probably another way that would have worked just as well, but we have found that aluminum rivnuts work well and are fairly easy to install for low-load applications. We have also used steel rivnuts for higher load applications, but they tend to be harder to install (and remove when they inevitably break) and not be as strong as a regular nut.

Re: Rivnut Tool
 

If your ACE is selling 6061, good for them! But I would bet you $10 that it's 6063 and I HATE that stuff, super gummy and nowhere near as stiff.

Please don't buy hardware store aluminum. Please.

Rivnut Tool
 

I shamefully admit that at least 50% of the metal on our robot was bought from Orchard Supply.

Never again...

Re: Rivnut Tool
 

This was all just scraps from my garage. For structural robot parts above the drive train, we use versa frame and 6061 channel (and a small amount of tubing) usually from Bayou Metals. When I do the more complete testing, I'll be sure to get some 6061 scraps from the recycle bin at the robot workshop.

Gummy? Would you please elaborate?

Re: Rivnut Tool
 

Lots of applications where you cannot get to the back side to use a nut and the material is too thin to thread.

Re: Rivnut Tool
 

When you machine 6063 Aluminum the chips tend to reform and stick on your end mills and other cutters.

Re: Rivnut Tool
 

The longer (.225") rivnuts arrived a couple of days ago, and I spent some time today in testing. I'm planning a white paper to be out before kickoff, but here's the gouge:

• I began by inserting the machine screw "dry", and tightening with a T-handle (I did not use arm strength; with limited hand strength, I can get to about 2 ft-lb with a T-handle). Unless that failed, I then disassembled the test unit, sprayed the threads with WD-40, and re-assembled for higher torque tests. All tests utilized new (or lightly stressed) stainless 10-32x1" allen-cap-head machine screws; I expect these to be a bit stronger and more consistent than "plain steel" machine screws.
• In 1/16" 6063 aluminum, I only tried the short rivnuts, because the longer ones would clearly not grip. The maximum torque supported with lubricated threads was 4 ft-lb, which theoretically corresponds to a clamp load of over 2200 pounds, which should have broken the machine screw. However, the failure mode was the rivnut pulling out of the aluminum through a "volcano" deformation.
• In 0.1" versaframe tubing (6061), the short rivnut performed sililarly to the 1/16" case above. The long rivnut secured tightly originally, and supported a torque of up to 6.5 ft-lb for several full revolutions. Failure was due to shearing of the machine screw near the head. After failure, there was definite visible deformation of the surface (~1/16"), and the rivnut was loose in the hole after failure of the screw.
• In 1/8" 6061-T5 C-channel, the short rivnut pulled out easily with about 2ft-lb of "dry" torque (provided by an Allen T-handle; torque estimated by hand). Note that in the preliminary test, I had applied far greater clamping force to the tool than should be required; in this case, I applied forces similar to those necessary to clamp in thinner material.
• In 1/8" 6061-T5 C-channel, the longer rivnut supported a maximum torque of about 6 to 6.5 ft lb. Failure was due to shearing of the machine screw, and there was no discernible deformation of the aluminum.
• In 1/8" 5052 plate (particularly, an AM-14U2 end plate), the behavior closely matched the 6061-T5 C-channel above in both cases.

Bottom line: Use the longer (.225) rivnuts in 0.1" and thicker material. TBD if a spacer or gusset will make mounts in VF thick wall tubing more secure.

Caveats: Due to budget limitations, we decided to try rivnuts this year in a very limited case. As we use 10-32 bolts for the majority of our structural work, this was the single thread we decided to experiment with this year.

Thanks. I have noted that sometimes holes drilled in 6063 are not as large as the drill bit would indicate; I presume this is somehow related to "gumminess".

Re: Rivnut Tool
 

Geetwo,

Help me understand your test. It seems that you are torquing the screw in the mounted rivnet to see when it will fail/stripout, is this the case?

Considering that the recommended torque for a typical 10X32 screw application is in the 30 In Lbs range, reaching from 48 to 80 In Lbs in most of the material is fairly impressive. http://www.federalscrewproducts.com/torque-chart.htm

Re: Rivnut Tool
 

Yes. As described several posts above, I was using a 1/2" nut and three washers against the stock so that I was pulling on the rivnut, not simply tightening against the flange.

I had already noticed that the stainless machine screws supported several times the rated torque, even a good bit over grade 8. What I found even more impressive was that all of the shear failures occurred at the same torque to within about 10% (my measuring precision with this tool at that torque). Further the torque on the threaded portion was probably quite a bit less than the torque I was applying, due to friction between the head of the screw and the large washers.

Re: Rivnut Tool
 

Testing is fun and you can learn a lot. Have you looked at the published ratings?
http://www.cardinalcomponents.com/as...properties.pdf

Like Clint mentioned fasteners under 1/4" will generally be measured in in/lbs rather than f/lbs.

Understand that the torque charts are a guide for a properly torqued fastener. These are within the working limits of the fastener. As you've discovered the shear point is quite a bit higher and material plays a big part.

I would think that if your seeing fastening system failures it is likely due to poorly designed joints and/or improper fastening system selection. Of course that's assuming proper installation. ;)