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Help! First time with bucked rivets was a mess :-(

bertschb

Well Known Member
Friend
I'm working on the Van's toolbox practice kit and did my first bucked rivets today. It was a disaster. Not only did I bend the metal adjacent to the rivet I was working on but I also added the dreaded crescent shapes. SUPER disappointed as I'm already a little overwhelmed with the thought of building this airplane.

I have two theories as to what happened. First, my rivet gun didn't come with the swivel head that I see on virtually all YouTube videos (and I've watched dozens and dozens of videos of people driving rivets). According to a video I watched from Cleaveland Tools, they don't recommend that swivel head (for several reasons). My rivet gun was walking around on the material even though I had it pretty perpendicular.

This is the swivel head I'm talking about:
y4mIlzYmBaZVKHCx8Kpa8TjjhgsX-4xbTVcZ-CyCn4UtNXJS9lnJqwfxJDQFREVFtOHSMHKpwVYJ_kbQpQ9as_Z3YSbUCNjyWXjZ7r6y3RdQjAVtubbtekAipEKx_6h6sVwPHr_-D-QaUt1FvETU8eHVfsMEg6iZc7-meQ-6qLhPaufx3wZ6JSCy695dCL44Qlv



My second theory is I didn't have the toolbox clamped down and maybe because it's so light, that caused the box to move around while riveting.

Here is the damage (the pictures actually look better than in person):
y4m1DORKC1OYj7AQnTU3Ytui3cN-76kVlfFELjUnSxAcHJV8nH1X-mU4YsZgMIrswfaKwodl6zFhljqGAV9ymw5zZqlmxlswfkp3gJjrnbNY4ClkTacZYGgwEhEqMgJ9GECRyTl8VXxENw0CwS9QwQLk_DorDKSItPgDiZK00e7v-ZWzOxa9H06eElmhj0cgBbZ


So my questions:
1- Should I be using that red swivel head thingy?
2- Should I secure (clamp down) any light pieces that I'm riveting?

There is no way on earth I'm touching real airplane parts until I figure this out and I just picked up my first kit (wings) a few days ago so I'm ready to start.
 
Yes, clamp it down. If it moves it will be difficult to buck. Swivel heads can walk also if not held perpendicular. Try clamping down before moving to purchasing a swivel head. If you decide to build an RV you will then probably choose to purchase one. Ask a local for help if needed. Bucking isn’t difficult to do once you learn how.
 
These kind of mistakes, especially if you are self taught, are very common at first. So don’t lose hope. Keep practicing. To answer your questions—

1) some people love the swivel heads, others hate them. I love them and recommend them. You just have to make sure the rubber part doesn’t stick up too high above the rivet set. There are a lot of threads you can search for about that.

2) you should always secure any piece that you are riveting if there’s any chance of movement. It’s hard to get a good rivet if the piece moves.

My best advice to you is to attend a building fundamentals class. You will learn all the basic techniques from people that have built planes before. Synergy Air is based in Eugene, Oregon, is well respected, and has regular classes. They can give you excellent guidance and the confidence you need to see the build through.
 
These kind of mistakes, especially if you are self taught, are very common at first. So don’t lose hope. Keep practicing. To answer your questions—

1) some people love the swivel heads, others hate them. I love them and recommend them. You just have to make sure the rubber part doesn’t stick up too high above the rivet set. There are a lot of threads you can search for about that.

2) you should always secure any piece that you are riveting if there’s any chance of movement. It’s hard to get a good rivet if the piece moves.

My best advice to you is to attend a building fundamentals class. You will learn all the basic techniques from people that have built planes before. Synergy Air is based in Eugene, Oregon, is well respected, and has regular classes. They can give you excellent guidance and the confidence you need to see the build through.

Unfortunately, Synergy Air is consolidating in Georgia and no longer has classes in Eugene. I know the OP tried to take a class there.

To the OP - have you reached out to Bend Build Assist? Don’t know anything about them, but they are close.

I also suggest you wait and start on the empennage before touching the very expensive wing kit. And don’t touch either kit till you have taken a class somewhere and are comfortable with riveting. Just my non-expert opinion.
 
Lots of practice. I was most of the way through my tail kit before I wasn't a metal menace.

Best thing to do is build the practice kit, drill it apart, and build it again. Lather, rinse, repeat.

Driving rivets is like hammering nails. Takes a lot of practice to drive 'em straight every time.
 
Brian,

Yep, you really beat up that piece of aluminum.

I would suspect several technique problems are in play:
- Yes, the piece needs to be secured. Trying to hold it steady while bucking with one hand and rivet gun in the other is a recipe for poor results.
- I would guess you are using a 3X gun with the pressure way too high. Try 30psi and work up from there.
- Bucking takes more skill than running the rivet gun. Practice that.
- I use the red swivel head flush set for 90% of the rivets. The straight flush set for perhaps 2%, a long and narrow flush set for 1% (both for tight spots) and the rest are back riveted.
- The rivets set with your squeezer are fair. You can improve by making sure the rivet is seated first (use a more clekos) as well as the dimple being full depth. Holding the squeezer just right takes a lot of practice as well.

Tip - cover the red swivel set face with some clear packing tape. This will eliminate scuff marks.
Tip - for round head rivets use ~3 layers of masking tape over the set face. This will eliminate “smileys”. Depending on how good you are the tape will last for 3-6 rivets, then replace.

Carl
 
Beginner

Don't fret. My first tool box looked much worse.
They look like too high pressure to me.
My Sioux 3X runs 22 psi for #3 and 30 psi for #4.
3M heavy packing tape is great for flush riveting
Gorilla tape is great for 470 rivets to prevent smileys.
Find a mentor. Don't build bad habits.
 
Thanks for the feedback guys!

As KatanaPilot said, I signed up for three different classes at SynergyAir in Eugene only to have all of them cancelled. Bend Builders Assist (BBA) is an hour away. They have a good reputation. My neighbor flies there, picks up staff and flies them back to his hangar for build help (another RV-14 builder). The only problem is they don't have specific classes like SynergyAir does. I spoke to a guy at BBA and asked if they had any kind of "fundamentals class" or an itinerary or anything to show what they would actually teach. They don't. Sooo, I guess I have to make a list of all the things that I don't know and ask them to cover it. $75/hour. He said it would take a couple days.

I think I'll order a swivel head and try it.

I do have a 3X gun. Cleaveland says to keep all air tools at 90psi but use a flow restricter at the gun which I'm using. Of course, I have no idea if it's adjusted properly but I did adjust it by turning it clock wise (assuming that reduces flow).

I'll go back to the toolbox now and I will definitely clamp it down before I try bucking any more rivets.
 
I do have a 3X gun. Cleaveland says to keep all air tools at 90psi but use a flow restricter at the gun which I'm using..

Might want to get yourself a regulator to attach at the gun end of the hose. Adjust it where it holds 25-30 PSI with the trigger pulled (for 3/32 rivets). About 5-8 more PSI for 1/8" rivets.

Correct air pressure is very important.
 
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Thanks for the feedback guys!

As KatanaPilot said, I signed up for three different classes at SynergyAir in Eugene only to have all of them cancelled. Bend Builders Assist (BBA) is an hour away. They have a good reputation. My neighbor flies there, picks up staff and flies them back to his hangar for build help (another RV-14 builder). The only problem is they don't have specific classes like SynergyAir does. I spoke to a guy at BBA and asked if they had any kind of "fundamentals class" or an itinerary or anything to show what they would actually teach. They don't. Sooo, I guess I have to make a list of all the things that I don't know and ask them to cover it. $75/hour. He said it would take a couple days.

I think I'll order a swivel head and try it.

I do have a 3X gun. Cleaveland says to keep all air tools at 90psi but use a flow restricter at the gun which I'm using. Of course, I have no idea if it's adjusted properly but I did adjust it by turning it clock wise (assuming that reduces flow).

I'll go back to the toolbox now and I will definitely clamp it down before I try bucking any more rivets.

If you are using 90 psi and a 3x gun, that’s a problem. As others said, try 30-40 psi. Go to harbor freight and get a mini regulator so you know what you have set.
 
One more thing...

I thought I should mention we moved to an airpark 6 weeks ago. Lots of builders here but we've only met a few of them. I'm reluctant to ask for help right away before I even get to know them. I don't want them to think I'm a nag.

My empennage kit is supposed to be ready in six weeks or so. Should I leave the wing kit in the crates and start on the empennage kit first? That was my original plan but the wing kit was ready first. It's just staring at me...
 

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If you are using 90 psi and a 3x gun, that’s a problem. As others said, try 30-40 psi. Go to harbor freight and get a mini regulator so you know what you have set.

Sigh...I've got a regulator. I will turn the pressure down.

Guess I'll remove the flow restrictor too since I have no idea how that affects the gun.
 
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I use the flow restrictor, turn it all the way down to start (clockwise), turn up as you get better. In my eaa sport air workshop (highly recommend), the saying was to have the gun purr like a kitten, not roar like a lion.
 
Regulator

Sigh...I've got a regulator. I was trusting the opinion of a YouTube guy who sells rivet guns for a living (and said all air tools s/b 90psi but use a flow restrictor). I will turn the pressure down.

Guess I'll remove the flow restrictor too since I have no idea how that affects the gun.

Ouch 90psi. I made the same beginner error. Again, find a mentor. Most builders can't wait to share knowledge.

Personally, I prefer a good mini regulator (RTI 1/4") either at the gun or on a short pigtail. It yields more consistent results. I set it and pressure stays where it's set for the session. I have two pigtails. One for low pressure with the RTI and one for high pressure like the pneumatic squeezer and drill. It has the HF regulator. No where near as precise but works fine for 90psi.

Many use a regulated supply from a plumbed circuit and others swear by the flow restrictor. You'll find a happy place.

I forgot to mention, I like my swivel set. As others mentioned, do a search on how to file down the rubber cup.
 
Sounded to me like you were saying you had the tank and line pressure at 90psi. But, you have the flow restrictor dialed way down. That's how I've been doing it. I'm using an ATS 3X rivet gun. I originally had a 2X gun that came with the kit from Cleveland.

When I was in exactly the same spot you are now, I got help from an old tin-basher that was a crew chief for one of the well known old Reno unlimited racers. He said my 2X did not hit hard enough or fast enough. He also said an AD3 rivet should be set in just a couple of good whacks, no longer than about a second.

Another thing he said was I should experiment with my tools until I found the precise settings that work for me. He said its going to take several thousand rivets before I would be really skilled at it. And as I gain more experience, I should develop some muscle memory and an intuition about how the gun and bucking bar are going to behave under different circumstances. This is why so many repeat offenders say the first airplane is to learn on. And, the 2nd is the dream.

Don't beat yourself up. And, don't let perfection get in the way of good enough!:D

Oh and one other thing: The springy swivelly thing - I keep it in the bottom of my taco-wagon just to show guys that come over, that I too wasted my money on one.
 
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Sounded to me like you were saying you had the tank and line pressure at 90psi. But, you have the flow restrictor dialed way down.

Correct. But, I only had the restrictor dialed down about half way. Again, I don't really understand how that thing works and there is no way to measure air flow or whatever at the tool so I just removed it and I'll use 25-30psi next time.

I just finished doing a couple dozen rivets with the pneumatic squeezer. Those went well so I ended the day on a high note. I am a perfectionist so this will be a struggle for me initially.

Back to Bend Builder Assist...when my neighbor needs their help, he flys there and picks up one of the employees and brings them back to his hangar. I thought that was a novel solution.
 
Don't get your hopes up that the swivel will make a big difference. What WILL make a big difference is securing the piece and using a lower pressure on the gun. The pressure I use for AD3 rivets is low enough that it takes a full 1 second to set the rivet if I'm using good bucking technique. I'd set the pressure a little higher for AD4 rivets, and it can take two blasts of 1 seconds each to set.

As for technique: Even after having set thousands of rivets now I sometimes (with decreasing frequency as I get better) end up with light dents in my skins, and it always happens when I lose concentration and neglect to hold the rivet set perpendicular to the surface. When I'm doing things right, I first get the set in the right place, then make sure my bucking bar is perfect and bucking hand braced. The last thing I do before pulling the trigger is put maximum concentration on ensuring the rivet set is in place and perpendicular, and I maintain that concentration until I release the trigger. FYI, I do this for universal rivets too, otherwise I end up with smilies. I won't even try to buck a non-secured thing because I know what will happen...

Last piece of advice, if you are working on a rivet and have even the slightest doubt you can keep the set in the right place and perpendicular while also doing a good job of bucking, it's time to call for help and get someone to buck. I make a big deal of reminding my wife how good of a bucker she is, which a) is absolutely true, and b) keeps her coming back. When I don't have to worry about bucking, I can have one hand on the trigger and the other hand holding the set in place. Works wonders.
 
Practice on scrap

Lots of advice here; practice is the key. I recommend to get some aluminum sheet, any grade or scrap will do. Drill rows of holes and just practice practice practice riveting pieces together. You can experiment with different pressures, different bucking bars etc and not worry about ruining an airplane part. I still sometimes do this to check the pressure when setting up for a riveting session.
 
My empennage kit is supposed to be ready in six weeks or so. Should I leave the wing kit in the crates and start on the empennage kit first? That was my original plan but the wing kit was ready first. It's just staring at me...

This is a tough question. The empennage kit is designed to be done first, in the sense that there are more complete, specific instructions, lots of hand-holding, etc., that will be lacking in subsequent kits. Starting on the wing is okay, just think each step through carefully before pulling the trigger.
I agree with the others: clamp down the work, try lower air pressure.
 
Turn the pressure down. Put in a few rivets in. Turn the pressure up a few pounds and try it again. Repeat.

Point is everyone’s optimal pressure is different. Experiment until you find the “sweet spot”.

Tear the first kit up. Learn from it. Buy another practice kit and make a second box. Toolbox kit number 2 will be far better.

You can still cleco, drill match, dimple/drill match and debur the empanage parts together while you practice on the practice kit.

By any chance do you have a builder nearby that could use riveting help or is riveting but doesn’t need help but you can watch or maybe help?

I had a newbie come over and I enjoyed teaching him. He learned how to hold a buck rivets and what a properly set shop end looked like. He was a great help riveting a wing bottom skin when he knew how.

Point is seek out the chance to learn and your empanage will speak volumes when you look at the results.

Heck, I’ll be riveting the fuselage next week. Come on down to Mississippi for a few days and I’ll take you under my wing. Put you up at my home, plenty of good food and drink and you will learn plenty about riveting and much more.
 
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I learned by getting thrown into the deep end at Braniff. It is all about practice. Practice, practice, practice.
The biggest thing you'll deal with is a AD4 and a lot of threes. Consider yourself fortunate you're not driving DD or Monel eights.
Personally if I can get access I prefer to squeeze rivets. You can get very consistent results, even a novice. You can usually get the money you spend for a pneumatic squeezer back when you're done with it.
If you can find a mentor like Webb.
 
I tee off a separate line for the rivet gun and use a dedicated regulator. I like that much better than in-line regulator. I also like my Sioux 2x gun - typically about 20 lbs OR LESS pressure for AD3 and 30-33 lbs for AD4 rivets. The thicker/harder the material you're riveting, the LESS pressure you need (energy goes into rivet, dissipated less by structure moving around). As others have said, the better you immobilize (clamp down) the workpiece, the better the results.

I like a straight mushroom set better than swivel, but others have other preferences.

Like this:

IMG_1962.jpeg


Larger version of photo here:

https://blogger.googleusercontent.c...BP8RzFPdjLbKfjDyiO_kllHqw/s4032/IMG_1962.jpeg
 
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Are you going to OSH this year? EAA offers their sheet metal course there and I think slots are still available. I took this class several years ago and was underwhelmed- poor tools, too many students, too few instructors, overpriced in my opinion - but it’s a alternative to no class at all.
 
Finish building the practice kit. THEN, dismantle it. Every rivet. Straighten what’s bent. And rivet it back together.

Learning how to remove a rivet is a skill that is just as important as how to buck one.

Don’t think of the practice kit as a project, think of it as a training ground. Add extra flush and round head rivets. Use some opps rivets. Install a nut plate where it’s not predrilled and remove it. You get the ideal.
 
Brian: Don't get frustrated, it takes lots of practice to get really good at hand riveting. Buy a couple of small sections of various thickness of al sheet and a couple of ounces of correct sizes of 470 and 426 rivets and drill and rivet away to get some practice. Use various combinations of material thickness and both flush and protruding head rivets to mix it up a bit.

At work, we send all new hires to a three week course in drilling, countersinking and riveting, no matter what their skill level is. That's all they do for those three weeks, 40 hours a week. Even some of the more experienced take a while to get back into the swing of things and produce quality riveting.

Also understand, there are times that no matter what you do, you just can't make things work right, and at that point, it's time to take a break and relax a little. I used to squeeze, drive or pull multiple thousands of rivets a week, when I was on the production line. Even so, there were times or locations that I couldn't seem to make a good rivet and I had to walk away or get another guy/gal on my crew to shoot, buck or pull the rivet to make the joint. Even with my background, right now, I'd have to expend a bit of time and practice a bit to get back comfortable hand riveting and be able to produce quality work.
 
Thanks for the advice and encouragement guys. It's very much appreciated. I've ordered another toolbox and I expect the next one to turn out much better.
 
First off, don’t be discouraged! This is a learning experience and you are doing the correct thing by practicing and asking for help. You, like the tens of thousands that have learned to buck rivets before you (think Rosy the Riveter and all those during the wartime that were hired in to produce airplanes that also had no experience) will soon gain the knowledge/experience needed to produce beautiful shop heads.

I don’t use the mushroom set with the rubber protector around it. I have one and even after grinding the rubber part down to where it sits flush on the piece (you must do this as the rubber piece is to long and will make your rivets sit proud) I found it to be to big/cumbersome and get in the way in to many places. The swivel head also made it more difficult to steady the gun for me. Take the time and get used to riveting w/o it and I think you’ll be better in the long run. Here’s how I started and taught my wife to run the gun also (although she prefers to use the bucking bar instead).

Any piece that is light enough to move around easily should be clamped down. Get your gun pressure set correctly (to high a pressure can make the gun difficult to control). Start with the gun on a wood block with low pressure and make sure you can control/keep it in one place and slowly work your pressure up to the pressure you want. From there you can move to a test piece of thick aluminum clamped in a vice or clamped to a table. If you’re using a mushroom head put a piece of blue painters tape over the mushroom head (just makes for a neater looking finish on the skins after riveting. I do the same with the universal rivet set also but usually use the thicker blue vinyl that comes off the large sheets.)

Drill a bunch of number 40 holes in your test piece and dimple/countersink them (this is a good way/time to set your countersink depth) and then set a rivet in each hole. Practice keeping the gun as steady/still over the piece as possible. The bucking bar hand should have just enough pressure to keep the bar steady but not push the rivet back through the hole. Rest/steady your bucking hand with your thumb/forefinger against the piece. This will keep the bucking bar from sliding/slipping around on the rivet and creating a nasty mark/dent on the inside of your piece. After you have set a rivet in each hole, grab your drill and drill out each rivet as this is also a process you need to be proficient at. This is another topic that can be done the right way and the wrong way. Do a search here on VAF for the proper way to drill out rivets. After they have been drilled out grab the gun and bucking bar and set them all again. Repeat the process trying different gun pressures until you are comfortable setting rivets and also drilling them out (you will need both skills when building your airplane). When you’re happy with your skill level and the look of your rivets go back and finish your toolbox.

Keep practicing and you’ll get the hang of it in no time!
 
Take your practice kit apart. No one is perfect, you will need to learn how to remove rivets as well as drive them.
 
Update:

OK, today I removed one of the side panels on the toolbox. Learned quite a bit about the rivet removal process. That went better than I expected. After this I buck-riveted the side back on. This went MUCH better than I expected!

Here are the changes I made:
- I put a sand bag in the toolbox to stabilize it.
- I turned the gun way down

I've gone back and forth multiple times as to whether or not to set the air pressure at 90psi and use the air flow regulator/restrictor that came with my Cleaveland Tools rivet gun or just set the compressor at 30(ish)psi. My first (failed) attempt at buck riveting I had the compressor set at 90psi and had the air flow restrictor connected but I had no idea what to set it to. As it turned out, it was WAY too high! Today I cranked the air flow restrictor all the way shut off and then opened it just a bit at a time until I thought it seemed about right. Just a couple of minor adjustments were needed to get it work great. It was WAAAAAY more controllable. Probably a combination of the sand bag and proper airflow setting on the restrictor.

I have a grand total of a couple dozen rivets under my belt so I'm still a TOTAL rookie. But, I'm now confident that I can buck rivets without destroying my airplane in the process.

On a different note - I had a bit of trouble removing a couple rivets. Can somebody send me a link to the tool they use to remove the back side of the rivet once the head is drilled out? The pliers I used worked "OK" but I'd prefer to use a proper tool for this.

Second question - When I first built the toolbox, I dimpled the pieces that were later joined individually. Today I used a #30 bit to enlarge a couple holes to use -4 rivets (mainly for experience). I used a 1/8" dimple die set to dimple the two pieces that were already joined together with some other rivets. Is this OK? I'm 99.9% sure it is but just want to make sure since the instructions call for dimpling the pieces separately before joining. I understand I have to slightly increase the gap on the dies because the two pieces together are thicker.

BTW, this is the air flow restrictor I'm talking about:
 

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Can somebody send me a link to the tool they use to remove the back side of the rivet once the head is drilled out? The pliers I used worked "OK" but I'd prefer to use a proper tool for this.

This is the proper tool. Grind the the rounded side so the jaws are flat. Even more than the picture. Chapter 5 in the instructions. If you grind them flat, they work well.
 

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Side cutters

This is the proper tool. Grind the the rounded side so the jaws are flat. Even more than the picture. Chapter 5 in the instructions. If you grind them flat, they work well.

Yep. Works great.
I also made a set of bars for the really stubborn shop head.
Takes an extra hand to hold the bar while someone taps it out. Bucking Bars

I don't recommend it for rookies, or anyone for that matter, but I also have a rivet set with a 3/16" hole for dies. Cleveland sells it. Buy a pin punch and cut it then turn down to 3/16. Turn the pressure down to about 10psi. Couple of hits and it pops the shank right out.
Rivet Gun Punch
 
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Way to go!
I use both the above, and a set of mini cutters for smaller spaces, and for really small the punch with a wood block backer.

Your 1/8 upsize is perfect for an oops rivet, where the head is a -3 but shank a -4. I’ve never heard that dimpling again was ok.
 
On thin pieces of aluminum you might bend it driving rivets out. Instead take a slightly smaller drill (e.g., #42 for AN3 rivets) and carefully drill right down the center of the hole. Use a drill stop so the drill goes thru the thickness of the sheet but stops short of the rivet tail. Do not enlarge the hole. I usually do this before removing the factory head, so I can use the little dimple on the head to center the drill. Once hollowed out, the tail and what remains practically falls out.
 
As for removing rivets in thin material (especially-4 rivets) I use a block of wood as a backer with a hole drilled in it that the tail of the bucked rivet just barely fits in. Remove the rivet head as normal then take a small punch and hammer and tap the shank out. The wood backer keeps the thinner metal from deforming when using the punch. If you have a helper it makes the process a little easier as doing it alone sometimes requires 3 hands to hold the block, punch, and hammer.

As for your pressure regulator I have the same one. I run slightly lower pressure at the tank regulator (45-50ish) and adjust the regulator at the gun from there. Practice, practice, practice and then use what works for you. Just b/c we like how something works doesn’t mean you’re not going to find a better combination that works for your gun, compressor, regulator, etc…
 
How I remove flush rivets with video below. I use a #40 drill bit for a -3 rivet as the diameter should be less than the dimpled hole. I drill it out to ensure the bit never touches any metal but the rivet itself. I only go as deep as I need to remove the head with the backside of the drill bit. I have a few bucking bars with holes drilled in them to use as a backer. Hit it with autopunch. The bucking bar with the hole can also be used on proud rivets using a very light hit from a flush set. Follow up with a solid bucking bar to ensure the shop head gets well set.

https://youtube.com/shorts/26BU9AhR1tE
 
Just a standard drill stop with a protector. Not really needed for drilling out rivets but I believe an important accessory when final sizing holes etc. If not used and the drill sinks 1/2 inch past the hole it will shift diagonally and result in an enlarged hole. I believe the drill stop gives tighter tolerances by not allowing the bit to sink too deep.
 
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