Solid Rivet removal
 

Hi all,

I would like to know what methods you guys (riggers/mech techs) use to remove aircraft solid rivets and whether you think there is any scope to improve the practice that you currently use.

Many thanks.

Kel :)

Perrin
 

Very carefully drill out rivet after head is off it could be punched out with punch.
Be sure not to drill to far if you are sure whats on the other side of the A/C skin as many old timers will tell you stories of drilling in wiring, pipework etc.
True story coming up, a fitter drilled out rivet, made a mess of it, to cut a long story short ended up as a 6" by 6" insert repair.
The best advice is to be carefull when drilling it out.:eek:

There’s plenty of info out there about this if you’re looking for it; proven and aviation industry approved methods.

Take a look at:

FAA Advisory Circular AC43.13-1b

Standard Aircraft Handbook for mechs and techs
ISBN 0-07-134836-0

Aviation Mechanic Handbook
ISBN 978-1-56027-591-6

Understanding Aircraft Structures
ISBN 978-1-4051-2032-6

Avoid these idiots.......
 

Manufacturers repair team turned up to renew a skin damaged (by the airline MX) after the aircraft skewed during jacking. The damaged section (about 22 feet by 6) was attached top and bottom by lap joints and butt joint either end. This "team" (probably an assortment of connies and old hands) proceeded to abrapad all traces of paint and protection from said joints in order to reveal the rivet and hyloc heads.

A few things:
1. some of the burnish marks looked about 10 to 15 thou deep !! seriously impairing damage tolerance
2. steel fasteners attacked in this way leave microscopic residue embeded in the alumimium which causes corrosion
3. the countersinks need re-making as the rivets will stand proud - this risks knife edge stress.
4. 2024 has a 2 thou layer of pure ally as a protective coating - now rendered useless.

:{

Always paint strip or media blast to reveal rivet heads.

I was there to oversee the insurance job - needless to say I reported this to the manufacturer, insurance co, owner etc and was ignored. Money changed hands, a 8110 (equiv) issued and off she flew. Fussy Brit I guess. If I'd done that when I was an apprentice I'd have been out the door.

Chapter 4

see

Advisory Circulars - Results for Document Number: '43.13-1B'

Good practice for universal head rivets is to file a flat carefully on the head then centre mark it for your drill starting point. Carefully drill the head so it can be removed, then carefully drill the shank until deep enough to remove the majority of the rivet material in the hole, without preicing the tail. If the rivet is a large diameter, I will drill at a slighty smaller diameter. Punching out the remains also involves supporting the joint from behind with a bucking bar if possible. Stringers and skins don't get cracked or distorted then!:E

Being an old sheety I would recommend the following.

1. Make sure you expose the rivet head (especially csk) remove paint.
2. If RH file a flat on the head.
3. Centre punch the rivet head, pref with dolly behind rivet tail.
4. Use 3/32 start drill.
5. Then use a drill slightly smaller than original rivet dia.
6. Drill head off
7. Use rivet dolly next to rivet tail and punch rivet tail out.

Obviously if you have thousands of rivets to remove it can be exhaustive, if you are removing the skin you can usually skip steps 1-4. Based on experience this does allow you to occasionally move off the rivet, I personally support the drill with my hand on the skin or member and slowly start the drill with the drill in step 5 as it doesn't matter if you damage any skin material or part that will be scrapped.

To avoid the drill running right through the skin and possibly damaging parts or cables behind the skin when drilling blind. I used to wrap solder around the drill bit from the chuck to the tip exposing just about 5-10 mm of the drill tip. The solder would prevent the drill going straight through the skin and the solder was soft enough not to cause any damage.

I miss the sheet metal work side of things and spent hours in my apprenticeship drilling rivets :rolleyes:

Hope this helps, but practice makes perfect :ok:

Or use a spring stop on your drill. Masking tape also can be used.. with care.:ooh:

Perrin
 

Just remembered I used blanking caps no damage to skin at all.
Have a good xmas out there on the line and in the Hangers boys.
ATB Peter:ok:

I used to use a 1/8th thick Steel strip, approx 4" x 3/4", bent to about 30 degrees with a hole in the end to place on the rivet head - the right size (e.g 1/8" for 1/8", etc - or metric for the new boys) it was rounded and smooth around the edges so as not to scratch.

Lay it on the top of round/uni heads and drill away - centers almost automatically without filing the flats - tends to wear after a bit but you got used to it. Can't remember many mishaps - but then, we were removing skins all the time!

Ex-431MU AEF trick

Anyone seen the film of kapton wire burning because of swarf contamination?
IMHO all sheeties should be made to see it.
Cover all looms before drilling and have a good hoover out afterwards.
& no I'm not a fussy B2,I'm B1 & used to be a sheetie years ago.

Yeah, mask off those areas where swarf is going to spoil your day when you come round to clean up.. That also includes control cables and pulleys, in fact everything you can. Fine collectors of debris all. It amazes me when you take up cargo liners, floors etc, how much ****e some sheeties leave behind after a job!! Then again, you don't get the 431 MU AEF / RSS QA inspector ripping your job apart on his final check!:oh:

Totally off on a tangent!!

Funniest thing I saw with one of those inspectors.. "That rivet head is mis shaped!" "No, Geoff.. Its a ladybird!":E

This Is The Basics!
 

There are so many chancers now in the industry, non apprenticeship trained people! Calling themselves Aircraft technicians! This was one of the very first things I learnt to do in my 4 year apprenticeship back in the early eighties! I have drilled out thousands of fasteners ( thats another word for rivets, bolts, hi-locks etc in case you didnt know) It astounds me that someone is coming on here asking this question!!

My advice is get someone to show you otherwise you will fek something up and you will look a dick!!!:\:=

7 hours 17 minutes into the new year and the "Most Helpful Response of 2011" award has been already won :D.

Well as it looks as the guy asking is REME, the question isn't as silly as it first appears.. Seriously!:E

Firstly,

Thankyou to all the guys that have responded to my post with a constructive reply.

The reason I started this thread is due to the fact I am in the process of designing and manufacturing a tool to aid in the removal of A/C rivets to improve the process. I have carried out this task frequently and thought of an idea to make the process more accurate and more efficient. I therefore canvassed for current practices used by the professionals that use this forum (excluding "itsallbollox")

Just to finish, "itsallbollox" (apt name) if you have nothing constructive to add to this thread kindly go elswhere and annoy someone else with your pointless boring posts that are about as intelligent as your screen name.....:mad:

These guys gou lots of practice:

Some years ago I was visiting Marshall Aerospace, when I was asked to look at an Air Transat L-1011 that was in for a C-Check. There appeared to be numerous loose rivets on the upper fuselage, corresponding with an area of beef up done for the L-1011-150 modification. The mod had been accomplished my an other maintenance provider several years earlier. To make a long story short. They had to drill out 30,000 rivets because they were install without sealent. About a year later the second TS TriStar modified by the same company had to have 20,000 rivets drilled out and replaced in the same area.

glhcarl,

30k rivets!!! So do you think there is a requirement for a tool to improve the removal process?, judging by the high ammount you mentioned using a center punch and a drill would take forever! :eek:

Several aircraft tool companies in the USA manufacture a rivet removal tool which has interchangable nose pieces for 3/32", 1/8", 5/32" and 3/16" to suit AN470 universal head rivets. It takes a 1/4"-28 threaded drill bit and has a 1/4 " shank. The better quality ones run the spindle in bronze bushings. If you are in the UK, I may have a link for a UK company..............

Air Drills, Boelube & Accessories - USATCO Rivet Removal Tool - Aerospace and Engineering Tools Limited

This looks like one of the better ones. And another UK co.............

Bardolph Aircraft Tools but their site ...........:hmm: That's why I like physical catalogs !

You will not get any quicker than using a popper, drill, a stopper, block and care brought about by experience and good training.

Especially for countersunk fasteners.

Several companies produce some wonderful Carlos Fandango drilling jigs for removing large close tolerance fasteners, and they can prove their worth in some applications. However they were never quick to use and for a lot of jobs, they were unusable.

A good sheet metal man should drill out 10 to 15 rivets in a minute and Marshall has lots of good sheet metal men. And a good sheet metal man does not need a center punch.

[QUOTEA good sheet metal man should drill out 10 to 15 rivets in a minute and Marshall has lots of good sheet metal men. And a good sheet metal man does not need a center punch.][/QUOTE]

I sort of love your quote because you use the word should>>

Aircraft are not yet standardized machines to the extreme of mechanized maintenance. The fact that an aircraft hull can not even be produced to the exacting standards to mechanize skin removal and certainly over a term of flight it grows and shrinks in unspecified areas.

Sorry drifted off topic, but spot on for you to realize that the best damb tool to remove a rivit is a sharp drill bit in a straight drill with a craftsman behind it. Loss is at human factor/skill. There is NO better answer.

10 to 15 rivets per minute??? That is cr:mad:p. 4 to 6 seconds per rivet to take the head off and remove the shank?? Hate to put a fastener back into a hole you drilled. 1st oversize every time!

Bloke would be taking absolutely no care whatsoever.. Very Flip Flop..:ugh:

Drills bits wander on starting without a pop mark to allow the tip to clear, even if the bit is sharp. Care is needed if you don't pop them to adjust for that wander.. That also blows your 4 to 6 seconds out of the water unless you like teddy bears..:E

Or two fat ladies?? 88!! :ooh:

Drilling out MS20470AD & MS20426AD rivets is pretty easy and quick, seeing as the head identification is already a central dimple (assuming there's not 20swg paint on top :)).
It's c/s Cherry rivets on light gauge structures that give me the most grief...

Huck rivets are even more of a bitch..

First, you do not drill off the head and remove the shank, one fastener at a time. You drill off hundreds of heads and then go and remove the shanks or better yet have someone follow behind using a hammer and punch to remove the shank.

Drill bit wander? Maybe if you don't know what your doing. Remember these people are professionals!

So am I mate, been doing it for 30 years... 4 to 6 seconds is an exageration.. You time yourself next time. Again, bloke behind you punching rivets out.. Somebody blocking behind? I have never seen 600 rivets removed in one hour.. Even with 3 flip flops involved.. And powered punches and minimal drilling of just the heads.

If you use a centre drill, fine.. My lot don't supply them, so it's standard twist drills. You start a 3/16" - 1/4" drill on a uni head and drill it straight with no start pop or a smaller pilot.. That web of that sharp twist drill wants to draw nice circles in that rivet head, even if you are perpendicular to the head and drilling at a satisfactory speed. Even a smaller drill does the same. The British ONC mechanical engineering qualification teachs you all about the cutting loads and forces that happen to varoius drill designs.

A 3/16" or 1/4" uni head takes more than 6 seconds to drill to a depth that the head will depart, when you hit it.. Err, head should be removed before you knock the shank out. Profesional people do. And with the larger rivets like 3/16" or 1/4" (that are used a lot on Boeings, especially spars, chords and frames), usually they go through a lot of material, that requires the shank being drilled.. Some **** broke my new punching snap by not drilling out the shanks.. and the shank didn't come out.

From the AC..

Disassembly Prior to Repairing.

have started to shear.

Carefully punch out a 1/4" rivet with only the head removed..Yeah..:eek:

Any professional sheetie that needs to centrepunch a rivet head to ensure the drilling process goes as plans is not quite as good as they may think or post they are.

I don't bother for anything small or the Ds/ADs that have the marks, because there is no need.:E

New Fasterner Removal Methiod
 

Wondered if you have seen that latest in fastener removal technology. Fasteners can now be removed by an EDM machine instead of a drill. (Electro Discharge Machining). There is a You Tube video of the machine in action. Go to:


Removes a titanium fastener in about 8 to 12 seconds with no pilot hole and second pass drilling required.

When My Jag sqn disbanded was popped in the Eng bay at 431MU for a couple of weeks until tourex......... Not happy

Was asked to go get a module from the storage building, drove the forks under the box and tried to lift it, no joy, several quick up and downs of the forks and there was an almighty bang and up came the box, got off the forks and looked behind the box to find I had tore out a good 20 foot of cast iron heating pipe..... thinking days to do, popped a box back in front and was gone before ever found, if indeed it was until they turned the heating back on in the winter...... :E last and only time I was not first line on a Squadron.

thread drift again, sorry.....

Curious if any of the old s/m guys have done any Taper lok installs or removals.Those suckers came out like bullets if you were not careful.

Re: New Fastener Removal Method
 

Does anyone on this forum have experience of the EDM system in the video above?

The manufacturer claims it's 4-5x as fast as drilling with less FOD and greatly reduced risk of airframe damage, so why isn't it widely used?

I would hazard a guess at cost and useability?

Wheeling that big box of tricks about might not be as handy as an airline and a windy.

yes, but its been a few years. Seem to recall a job on a Tristar upper wing skin that involved Taperloks..

a 9x rivet gun wins every time...

We had one of those EDM systems turn up before Xmas. Called E drill. Cost £20k and never been out the box. The smallest size fastener it does is 5/32. You have to set it up for each fastener type. £20k gets you a lot of drill bits. I could go on and tell you about the window polishing robots we go at $500k that sit under dust sheets. We only polish a couple of windows a year!
Removing rivets you need a windy drill, drill bits, hammer and punch. Or if your doing thousands, put a punch in your rivet gun for the tails. You could be doing advanced rivet removal by drilling off the tails. But not recommended

EDM fastener removal system
 

The EDM system in the video is called E-Drill. Its only been in the market for a few years, and in this industry adoption rates of anything new and different are glacially slow. It removes fastener sizes from 3/32" to 3/8", and broken drills, taps and easy-outs.

...and in the interests of full disclosure I'm the primary inventor! So I'm cautious not to violate forum rules so dont ask me how good it is :mad:

Brightspark could have sworn the instructions said 5/32. Still your doing better than me I've invented nothing.
Things take time to catch on in aviation and even longer in aviation maintenance. A lot of the time it's through choice, if it ain't broke don't fix it. I'd still rather be using paper maintenance manuals. But also cost counts to the adoption of new technology. If its expensive and you can get away without needing it then you don't usually get it.
Another thing is mind set. We have guys who enjoy repair, sheet metal work and modifications and part of that is getting the drills out and using your skill and hand tools to get the job done. They are also on the most part totally mechanically minded so any thing electrical/electronic that will require some form of setting up they will just switch off and not engage with. It might be easier to use and faster but they won't get it. Plus if you have to read the instructions then forget it. No one likes reading the instructions

A little more info
 

Hi 146fixer,

E-drill is available with 2 different hand-tools; the EG covers -3 to -8 fasteners, and the CG covers -5 to -12. Sort of similar to a 1/4" chuck or a 1/2" chuck (almost).

If I'm guessing right who and where you are, hopefully someone will arrive soon to uncrate yours and show you how to use it. Might even be me! I'm going to be clairvoyant and say I predict you have a lot of monel cherry's in your future!

Who was Claire Voyant anyway?