I hate rivnuts

This forum has been developed to discuss maintenance topics in Canada.

Moderators: sky's the limit, sepia, Sulako, North Shore

Post Reply
User avatar
Colonel Sanders
Top Poster
Top Poster
Posts: 7512
Joined: Sun Jun 14, 2009 5:17 pm
Location: Over Macho Grande

I hate rivnuts

Post by Colonel Sanders »

I really do. Honestly, does it really take that
long to drill the two little farken holes for the
nutplate and squeeze a couple of tiny rivets?!

There. I feel much better now.

Carry on,
---------- ADS -----------
 
Bent wrench
Rank 1
Rank 1
Posts: 30
Joined: Sun Jul 03, 2011 11:36 pm
Location: Alcatraz

Re: I hate rivnuts

Post by Bent wrench »

I agree Fawk rivnuts and lazy people
---------- ADS -----------
 
Bent wrench
Rank 1
Rank 1
Posts: 30
Joined: Sun Jul 03, 2011 11:36 pm
Location: Alcatraz

Re: I hate rivnuts

Post by Bent wrench »

I as well feel better!
---------- ADS -----------
 
bring me the horizon
Rank 2
Rank 2
Posts: 99
Joined: Mon Sep 24, 2012 6:48 pm

Re: I hate rivnuts

Post by bring me the horizon »

...I have no beef with the rivnuts. I find them quite useful when fastening together interior panels which otherwise would make tethering an anchor nut or similar difficult to impossible. It's basically a blind riveted nut.

Do you all hate Cherry max rivets as well?
---------- ADS -----------
 
User avatar
Colonel Sanders
Top Poster
Top Poster
Posts: 7512
Joined: Sun Jun 14, 2009 5:17 pm
Location: Over Macho Grande

Re: I hate rivnuts

Post by Colonel Sanders »

Cherry Max rivets are the spawn of the Devil.

Well ok, maybe not that bad. They're expensive,
and lazy people often use them even when they
have easy access to the other side, which grinds
my gears.

Is it really that hard to buck a rivet? They're so
cheap and simple, and so easy to drill out.
---------- ADS -----------
 
User avatar
Taiser
Rank 6
Rank 6
Posts: 403
Joined: Fri Mar 30, 2012 4:17 pm
Location: YQT
Contact:

Re: I hate rivnuts

Post by Taiser »

HEY HEY HEY!!! Don't be dissing the Cherries! My entire homebuilt is built with Avex (cherry like) rivets!!! :lol:
---------- ADS -----------
 
Pavese
Rank 4
Rank 4
Posts: 217
Joined: Sun Jan 14, 2007 10:26 am

Re: I hate rivnuts

Post by Pavese »

Taiser wrote:HEY HEY HEY!!! Don't be dissing the Cherries! My entire homebuilt is built with Avex (cherry like) rivets!!! :lol:
+1 And they're blind rivets, not pop rivets!

The rivnuts keep the price of your airplane lower. Much as I like the elegance of a nut plate, I understand the need for value judgements to manage sticker shock :wink:

BTW, I hate when rivnuts spin but I also can call on the experience of my favorite AME to make all well again! :mrgreen:

D 8)
---------- ADS -----------
 
crazy_aviator
Rank 8
Rank 8
Posts: 917
Joined: Thu May 01, 2008 10:13 am

Re: I hate rivnuts

Post by crazy_aviator »

After having owned over a half dozen CH 200-250-300 aircraft, BRITISH avex rivets are OKAY for this AME. I agree that Rivnuts and CHERRY rivets used when access is sufficient for the experienced AME to install is FOOLISNESS :D
---------- ADS -----------
 
Valkyrie_XB70
Rank 2
Rank 2
Posts: 70
Joined: Wed Jul 02, 2008 5:50 pm

Re: I hate rivnuts

Post by Valkyrie_XB70 »

Long as the rivnut is installed correctly (a small notch is cut into the hole prior to squeezing) I don't mind them that much. When people don't do that the rivnut will eventually begin to spin when removing the screw....that grinds my gears.
---------- ADS -----------
 
User avatar
CamAero
Rank 4
Rank 4
Posts: 272
Joined: Wed Feb 01, 2012 11:27 am

Re: I hate rivnuts

Post by CamAero »

I always cut the notch and usually glue them in with JB Weld as well.
---------- ADS -----------
 
iflyforpie
Top Poster
Top Poster
Posts: 8132
Joined: Tue Apr 15, 2008 12:25 pm
Location: Winterfell...

Re: I hate rivnuts

Post by iflyforpie »

I don't have any problems with rivnuts; I have problems with people who don't install and use them properly.

If you don't drill the hole, cut the notch, and squeeze it properly (with all of the threads engaged into the tool), it won't work very well.

If you are using structural hardware or tightening it within an inch of its life, it won't work very well either. The same thing in reverse happens when you use non-structural fasteners on locking steel anchor nuts... ....have fun drilling them all out. JB Weld not only encourages people to over tighten, but makes it real fun to remove. Rivnuts should never be used for structural purposes and really only should have the screw tightened about a 1/4 turn from snug.

It is possible to install anchor nuts blind in place of rivnuts... but the hole isn't going to be any smaller even with low profile anchor nuts, it is going to be a lot more time consuming as you fish each one through and position it with lockwire... and it is still going to be held in by junk 3/32 CCR rivets that the first knuckle dragger with a screw gun is going to destroy.
---------- ADS -----------
 
CID
Rank 11
Rank 11
Posts: 3544
Joined: Sun Jun 19, 2005 6:43 am
Location: Canada

Re: I hate rivnuts

Post by CID »

I avoid rivnuts whenever possible and certainly when attachment really matters. One of the biggest problems is the use of steel screws in aluminum alloy rivnuts. They wear the threads after just a couple of uses. This doesn't apply to the steel rivnuts like the ones used to hold the seat track down in an RJ. Those things are great.
---------- ADS -----------
 
GyvAir
Rank (9)
Rank (9)
Posts: 1817
Joined: Mon Mar 12, 2012 7:09 pm

Re: I hate rivnuts

Post by GyvAir »

iflyforpie wrote:I don't have any problems with rivnuts; I have problems with people who don't install and use them properly.
+1

They have their places, but those places are few.
If there's going to be any side-loading/prying/fighting at all as you install screws into them, they're not going to last and you're going to be cursing the idiot that put them there. They're for light installations that get installed and just stay there; not something that's going to come out for regular access, inspection or servicing.

Not all rivnuts have a key on them for a notch, by the way. (In case anyone's reading this thread and looking at a keyless rivnut, wondering what gives?)

An alternative I've used with better success is Nutserts. It's still not an anchor nut, but it sure beats an aluminum rivnut in many applications.
---------- ADS -----------
 
bring me the horizon
Rank 2
Rank 2
Posts: 99
Joined: Mon Sep 24, 2012 6:48 pm

Re: I hate rivnuts

Post by bring me the horizon »

How about well nuts? When those brass inserts cross thread with the steel screws and the whole fricking thing will just spin in it’s bolt hole :shock: . I have actually never found these things very practical unless it’s anchored to fiber-glass or honeycomb structure and again, for very light applications.

The only advantage to well nuts is that they come out pretty easy when you’re fed up with them. Just pull ‘em out with some duckbills and a healthy grunt.
---------- ADS -----------
 
User avatar
Colonel Sanders
Top Poster
Top Poster
Posts: 7512
Joined: Sun Jun 14, 2009 5:17 pm
Location: Over Macho Grande

Re: I hate rivnuts

Post by Colonel Sanders »

(threadjack)
My entire homebuilt is built with Avex rivets
If so, I might suggest reading this:

www.pittspecials.com/articles/MurphyRebel.htm

which is what I learned about pop rivets in aerodynamically
critical areas. Might help.
---------- ADS -----------
 
User avatar
Taiser
Rank 6
Rank 6
Posts: 403
Joined: Fri Mar 30, 2012 4:17 pm
Location: YQT
Contact:

Re: I hate rivnuts

Post by Taiser »

Nice article, don't apply much on my plane. Takes off in 100' with a stall of less than 30 mph and climbs like a mountain goat! I'm also installing the vortex generators. Compared to the rebel, my wing is insanely fat so lift is never an issue anyways, in fact the 750 is so "dirty" even if I flushed all the rivets on the wings I don't think I'd get more than a few knots speed anyways. I pay the price by it not being a speed demon, but I don't need it to be! :lol:
---------- ADS -----------
 
iflyforpie
Top Poster
Top Poster
Posts: 8132
Joined: Tue Apr 15, 2008 12:25 pm
Location: Winterfell...

Re: I hate rivnuts

Post by iflyforpie »

I'm wondering if the stalling issue you were having was more of a washout issue than pop rivets CS? A few tweaks to each jury strut might have been all it needed.
---------- ADS -----------
 
User avatar
Colonel Sanders
Top Poster
Top Poster
Posts: 7512
Joined: Sun Jun 14, 2009 5:17 pm
Location: Over Macho Grande

Re: I hate rivnuts

Post by Colonel Sanders »

a washout issue
Maybe, but the ailerons didn't seem to have any
unpleasant behaviour. And, more than one Murphy
Rebel had the exact same problem. Mind you,
maybe the build instructions don't have the correct
rigging numbers.

The engineering on a lot of homebuilts is a bit
underwhelming. As it is one some certified aircraft,
I might hasten to add.
---------- ADS -----------
 
Edo
Rank 7
Rank 7
Posts: 577
Joined: Wed Feb 18, 2004 8:39 pm

Re: I hate rivnuts

Post by Edo »

I once heard an old story about Cessna and flush rivets vs standard solid round top rivets.
As the story goes they built and entire 172 wing with flush rivets and test flew it. Then every rivet had a freeze dried split pea super glued over it. The aircraft was test flown again and again, between every flight a row (root to tip) of peas was removed.
Eventually a balance point of stall characteristics vs airspeed vs cost of install was reached, setting the standard for the leading edge and 1/3 or so of the wing to be flush riveted.
---------- ADS -----------
 
Post Reply

Return to “Maintenance”