Thread: Rivnut/Nutsert Experts?

What I don't like about the hand tool, is that if it's dropped and lands on its top, it usually bends the knob or breaks it off.
Kryn

A question about the Makita impact driver Pete. How does the bit release collar operate. My Bosch has to have the collar operated to both fit and remove bits, but the Stanley can have bits just pushed in and when removing bits it pops them out so it is a simple one hand bit replacement. If I had not found this set I probably would have bought Makita. The other thing I noticed is that the speed of the drill and driver is quite different. The driver does 2800rpm while the drill maxes at 1500rpm.

Dean

Originally Posted by Pete F

Kryn, one more question. With your technique (dare I say, cheat ), how did you unload the nut and now the tool itsel, with the driver once the nut is set? Did the tool have something small enough to grip with the chuck? Most of the manual tools I've seen have a knurled or similar knob to turn. That was always the most PIA part of it in my book.

I'll ask around at work to catch up on how the guys do it these days on low-volume (by aviation standards) work. When I was in the hanger I was mainly doing simple maintenance on engines, and didn't take as much notice of the airframe side of things as I now wish I had. They were manly just an annoying bunch *

*Anyone who has worked in a hanger with a bunch of guys riveting will understand that joke

Pete, I doubt that you will find any Rivnuts/ Nutserts installed anywhere on a modern commercial aircraft structure, they are too unreliable, however there will be Nutplates or Anchor Nuts every where.

I have seem a form of Rivnut used on some Avionics equipment cases and on pallets and containers (ULDs)

Ah interesting, thanks. I haven't had much to do with the hands-on side of things with large aircraft structures, and that all came from light aircraft. They were used by the gazillion in GA and I'm pretty sure are still used in amateur built aircraft. Just as you say, I've also seen them still used in the avionics area in large aircraft in addition to instrument panels etc. I'll try to pay more attention as, unremarkably, it's not something I notice much.

When you say "unreliable" how is that? As I mentioned above, I know some guys hated them but I never asked why. Generally speaking the failures I've had are them failing to grip on the skin they're attached to and spinning. I've cursed many a time as a result. Is that the unreliability or is it something else? It's really outside my area so I don't know, but I can imagine the nutplates would take up more "real estate" that might be a bit more precious on light aircraft, also the large commercial aircraft are very noticeably built to a far different standard of quality and the nutplates would be more work (ie expensive) to install. Mind you, it could be worse ... a helicopter

Speaking of installing, do you know of any 1/4 turn DZUS or similar fasteners that can be installed like rivnuts? I think a 1/4 turn fastener is often a very elegant solution when things need to be opened regularly, but I've never actually installed any myself. I have some where the plate slips over the edge of the material, and they're generally rubbish in my book, I don't like any of those edge plate things as they invariably loosen up. I also vaguely recall some cowls etc where the receiver plate was some kind of wire arrangement on a plate (a couple of parallel spring wires???) It's too long ago to remember the details, but I do remember they were basically the epitome of crap, indeed I think when you look up "Crap" in the dictionary it has a picture of those wire plate thingies. It would be nice to find something where the backplate is nice and secure, but is also easy to install.

Originally Posted by Pete F

Speaking of installing, do you know of any 1/4 turn DZUS or similar fasteners that can be installed like rivnuts?

There's a bunch of stuff including a description of a DIY tool for use on a pommy sportscar hood.scroll 4 lines down -its titled DZUS Fastener tips

Here :

https://www.google.com.au/search?q=D...EIMTAC#imgrc=_

Dzus fastener base.jpgDzus tooling kit.jpgDzus fastener tool.jpg

I've seen these used on Off Road Racing vehicles, the back plates were welded to the frame, or pop riveted to the backing that was overlapped by the top piece. Found this page on Google, if it's of any help. Dzus Fasteners - Bullant Performance Products

Kryn

Originally Posted by Oldneweng

A question about the Makita impact driver Pete. How does the bit release collar operate. My Bosch has to have the collar operated to both fit and remove bits, but the Stanley can have bits just pushed in and when removing bits it pops them out so it is a simple one hand bit replacement. If I had not found this set I probably would have bought Makita. The other thing I noticed is that the speed of the drill and driver is quite different. The driver does 2800rpm while the drill maxes at 1500rpm.

Dean

The Makita sounds similar to the Bosch, there is a collar that needs to be pulled forward to insert bits. Whether it needs to be pulled forward to release them also depends on the bit itself. Decent bits have a collar on them that is gripped by the tool, so they won't release. Cheap bits often don't have that collar and they can just be pulled out. I don't like the ones without a collar as they're not secured properly and can fall out as the Makita is designed to have that collar with the bits. Either way it's always a two handed operation and I honestly can't imagine a scenario where any tool could be changed with one hand. One hand holds the tool and you use your thumb and index finger to pull the collar forward, the other hand inserts the bit. I've used hex drives on other tools but not other impact drivers, however I by far prefer the Makita setup (and no doubt other brands) with collared bits.

Yes I don't think you would be disappointed with a Makita, and there's a reason they're so popular with Tradies. I'm seeing increasing numbers of Milwaukee Tools out there, but wonder if that's more a matter of promotion. The problem however is the manufacturers suck us in to their cordless vortex and it can be pretty difficult to escape from. For example I just happen to use Makita, and can't think of any tools of theirs I have that I'm genuinely disappointed in or wish I'd bought a different brand. However that's just as well, as if I decided I wanted to use, say, Milwaukee, I'd be SOL as the batteries are obviously brand specific. I have 5-6 batteries and they rotate amongst the tools. If I went to another brand I'd have to get another charger, would need a whole new set of batteries, I couldn't swap them right there and then with another tool etc etc. So the first cordless decision anyone makes is actually pretty important if they think they're going to buy more tools. I don't at all suggest going cheap, and unless that's the only tool they buy, it often works out more expensive in the long run as subsequent tools will require their own batteries/chargers.

My 18V Makita is max 1500 rpm IIRC. I can't remember what the impact driver is, but I want to say it's 2300 rpm (???). Not certain though. But that's not the whole story. The point I was making above is that with a driver (with a clutch) they normally go at maximum rpm the whole time you're driving the fastener. Indeed with the specific drivers they spin at 4000 rpm and generally speaking you don't even stop the motor. Just pull the trigger, and even with non-collated types, the bit will be spinning at 4000 rpm when it's setting the screw. With a drill/driver and you adjust the clutch so the fastener either doesn't strip, or sets at the correct depth etc. If I'm Gyprocking I'll often use specific Gyprock bits, but that's a whole different story. With an impact driver, how fast you spin it will depend on the fastener you're using and the job. However there's a good chance (if it's a decent driver) the torque it can produce will be greater than the torque required for the fastener. In metal screws it may strip them (or break them, don't ask how I know this), and in wood they can bury the head too far. Some brands have a maximum and minimum fastener size, and it relates back to this. My Makita will comfortably drive a bugle head landscaping screw clean through 50 mm treated pine sleepers without even slowing down! So you need to throttle back as the head comes close to being set. It reduces the torque, but also the rpm and that can make them slow to use (relatively speaking of course) if the fastener is fussy. Normally it's not a big deal, but when you're doing hundreds and thousands of screws, that additional time adds up. Today (or more likely tomorrow with this, welcome, rain) for example I'll set a couple of hundred SS screws and don't want to be wasting time. Like you, I use an impact 99% of the time and almost forget about using a driver. So I'll normally have the drill(s) set up with drill bits, and the impact will drive the screws. However when I'm doing larger jobs I'll set up one driver to drive the screws as it's faster. I think a lot of people don't care whether screws on a job are all set identically, that's their business and they can knock themselves out. I personally think a job where all the screws are set to precisely the same depth and are exactly in line etc etc looks professional, especially with the "bling" of stainless. But I don't want to waste time getting that result, hence why I set up the tools the way I described.

The bits I am talking about are the normal longer grooved bits that are gripped by the tool, extension etc with a locking collar. I can just push one of these bits in without touching the collar. The collar is moved by the bit to allow its entry. Removing the bit involves pulling on the collar and releasing it. The bit is pushed partially out so it is no longer locked. The same hand can then just take the bit out. I find this really handy when using the driver in awkward positions where I cannot use both hands easily for bit changes.

Finding good bits can be a bit of a challenge. I wanted a spare #2 square drive bit. I asked at a local hardware store and was told that this new brand was popular with builders. I bought one to give it a try. I had issues from the start, but persisted because I was doing a lot of screws on awkward angles. I finally tried some in a perfect straight ahead position and still had the socket ripped out by the bit. The bit itself was undamaged. I don't think it had the right shape and worked its way out. My usual bit is years old and still works perfectly, on the same screws. I like these screws as they (usually) are gripped very securely by the bit.

My step son used all Makitas when he was running a plastering team. He had quite a lot and multiple batteries. I don't think he uses them much any more as he has upgraded to running a couple of companies in the same field with a vastly larger turnover. He did some plastering for me with the strip loading screw guns. They were pretty quick.

Both of my impact drivers were bought because they were cheap. The Bosch 3 piece set including a recipro saw was just over $200 and I think the Stanley was around the same price for 2 pieces. Each set came with a battery for each piece.

Due to that same welcome rain, today I managed some spare time to try a few rivnuts with both drivers and the supplied tool. I found both drivers would work quite easily with the M6 steel nuts I was using. I used a strip of steel with a 6mm hole to prevent the nut from spinning as I suggested I would try. The first time with the Stanley the nut still spun so then I slowed it just a bit until it gripped the metal and back to full trigger. I was again driving with a hex bit in an M6 SHCS. I forgot to lube the threads to see if that helps.

Dean

Originally Posted by Pete F

When you say "unreliable" how is that? As I mentioned above, I know some guys hated them but I never asked why. Generally speaking the failures I've had are them failing to grip on the skin they're attached to and spinning. I've cursed many a time as a result. Is that the unreliability or is it something else? It's really outside my area so I don't know, but I can imagine the nutplates would take up more "real estate" that might be a bit more precious on light aircraft, also the large commercial aircraft are very noticeably built to a far different standard of quality and the nutplates would be more work (ie expensive) to install. Mind you, it could be worse ... a helicopter

Speaking of installing, do you know of any 1/4 turn DZUS or similar fasteners that can be installed like rivnuts? I think a 1/4 turn fastener is often a very elegant solution when things need to be opened regularly, but I've never actually installed any myself. I have some where the plate slips over the edge of the material, and they're generally rubbish in my book, I don't like any of those edge plate things as they invariably loosen up. I also vaguely recall some cowls etc where the receiver plate was some kind of wire arrangement on a plate (a couple of parallel spring wires???) It's too long ago to remember the details, but I do remember they were basically the epitome of crap, indeed I think when you look up "Crap" in the dictionary it has a picture of those wire plate thingies. It would be nice to find something where the backplate is nice and secure, but is also easy to install.

Yes Pete, Spinning after losing their initial grip is the main problem. I don't have any real answer to your other questions although Camlock Fasteners could be an option if you don't like the traditional Dzus style with the wire. You can look them up online in the Aircraft Spruce catalogue.

Ok thanks. I mainly use Aircraft Tool Supply for this type of thing but will check both when it comes time. Some say Spruce are better but I've never used them.

I've been asking around work, and as you quite rightly say, rivnuts aren't used much in large commercial airframes, and they are limited to a bit in the cabin and avionics etc. The issue as mentioned is them spinning. I don't know much about nut plates, other than seeing them everywhere, as I've never had to install them. I don't believe I would use them outside aviation as I can imagine they would be quite an effort to install. Many of the guys I work with have/are building homebuilts, and I know they use rivnuts there, but I doubt they would be used in such quantities the guys would have any great experience with them.

I did did come across a hybrid type rivnut-plate, which was interesting Structural Fasteners – Special Purpose Fasteners – Rivet Nuts and Blind Fasteners (Nonstructured)

Even further completely OT, but something I learned recently, was even Arbus still use imperial aircraft threads through the aircraft. Given the J series is available in metric I expected they would have gone metric, but nope, all UNF.