Getting Started with Rivets

My team has always used 8020 and t-nuts for our robots, but I want the team to transition towards using box tubing and rivets. I’ve read older threads about this and my understanding is that blind rivet supply is a great place to buy rivets in bulk and that pneumatic rivet guns are great but not allowed at competitions. I would greatly appreciate it if anyone could help answer the following questions.

  1. How good are pneumatic rivet guns? Even if we can’t use them at competitions, are they worth getting? If so, which ones are recommended?
  2. What size rivets are appropriate for fixing plates and mechanisms to box tubing? How many rivets are generally required to make a strong connection?
  3. Which manual riveters are good for using at competitions? I’ve heard good things about the astro 23 and 26.
    Thank you in advance for your time.

Pneumatic Rivet guns are allowed at competition, We have used one in our pit with an air compressor for many years without issue. Here are a few links to what we use:

People have also given great reviews to the Milwaukee M12 Electric rivet tool, Which I am a fan of because it does not need the air compressor.


Side note, make sure you’re using aluminum body rivets. They’re much easier to drill out if you never need to remove something. I’m partial to using aluminum body, steel mandrel rivets, but people do use aluminum/aluminum. +1 to Blind Rivet Supply as a source.

Absolutely worth it. I’ve been on teams with nicer pneumatic rivet guns, but these these are so much cheaper that we just replace them whenever we kill one past the point of repair (usually about 1 per season).

It’s not that pneumatic rivet guns are specifically disallowed at competitions, but some areas tend to be suspicious of teams that bring air compressors with them to tournaments (even though I can’t find anything in the manual that specifically disallows this).

Milwaukee has an electric riveter as part of their M12 series which I’ve heard great things about, but is a bit pricey.

I’d highly recommend sticking to a standard fastener size for most of your applications if you’re switching away from 80/20. The two most common FRC standards are 10 bolts and 3/16" rivets (both of these fit in a .201" hole), or 8 bolts and 5/32" rivets (both of these fit in a .159" hole). Which standard you go with is probably dictated by what COTS parts you use the most; the VEX Versa* system is all predrilled for 8 and 5/32", along with their sprockets and gears, etc. Most everything else uses 10 (as it’s the CIM mounting pattern).

I don’t have any specific model recommendations, but the style you linked (much larger symmetrical handle) are much easier to use than the smaller style that requires more grip strength.


The Milwaukee rivet tool is awesome. If you are buying a $250 compressor specifically to run a rivet gun, you should get the Milwaukee rivet tool instead. The next most used rivet tool we have is the easy squeeze manual rivet gun from McMaster Carr (97543A120). We also keep one of the generic manual ones around for hard to reach areas. We have an Astro 23, which worked great but has been almost completely replaced by the Milwaukee riveter.

We used 5/32 rivets for the previous few years, but have switched to 3/16 rivets as standard. We tend to follow the VexPro gusset patterns which usually ends up with 4 rivets at 1/2" spacing if attaching to the end of a tube. if you’re going into a 2" face of tube we put holes for at least 8 rivets on the same spacing, but will probably not use all of them. If the plate runs parallel to the tube for a large distance we usually go to a 1" spacing on the rivets.

I would consider keeping a pack of high-strength rivets in reserve, just in case you run into a situation where the regular rivets aren’t surviving, and you can’t easily substitute a bolt and locknut.

(Write on the packaging that they’re special high-strength rivets, just so nobody uses them up on something trivial, or installs them and wonders why they’re having trouble drilling them back out.)

Also, keep a pack of rivet washers on hand, in case a hole gets drilled out too large.

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I’ll bite:

It’s not that the compressors are a legal issue (though… they CAN be, and I’ll get into that later). It’s that they’re a tournament logistics issue for many events. Lots of events run generators for the event, and often if there are enough compressors firing up, the breakers can trip. Loss of power for some section of the pit (and possibly, if the event wiring is off enough, the field). This is a bad thing, if that wasn’t obvious. So bringing compressors is generally a “talk to the Powers that Be and see if they’re feeling nice this event” sort of deal–with the understanding that if a compressor takes out the power it’s gone in a heartbeat.

The legal issue comes when teams decide to fill their onboard tanks with a nice tool-powering compressor. Per the rules, the robot has one compressor, controlled by the RIO, and all the air on the robot comes from that one compressor. It’s quite possible, with about $10 worth of parts from McMaster, to build an adapter that will allow the robot to be filled from a shop compressor–which is illegal, at least partly for safety reasons. I have seen one at a competition. Though I can’t say I’ve seen one used at competition at any level–the one I saw was promptly pointed out to the LRI who had a chat with the team the next time they were in their pit–and I understand that it quickly disappeared.

But, in general, nothing specifically bans shop air compressors at competitions.


This is my understanding of why they’re actually apprehensive about it.

For reference, I’ve always brought compressors to tournaments to use a variety of air tools. Getting annoyed volunteers telling us it’s illegal and subtly accusing us of using it to fill our robot is quite annoying. Someone coming up to us and politely asking is to turn it off for short periods of time when they’re experiencing particularly high load on the generators usually results us in happily complying.

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I remember a comp a few years back (I want to say Ventura 2016) where event staff was giving a team some trouble for that on practice day, only for them to reveal the compressor running off a UPS tucked in the corner the next day.

I would gladly pay $150 to not have to use a hand riveter on 3/16 rivets for a whole comp. (this is before the m12 tool was released)

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My team had a bad experience with 1/8" rivets. (“The front shooter fell off”.) Since then, we’ve used aluminum 3/16" rivets, and not repeated the experience. Our chassis have been west-coast-style, made of 2x1 1/8" aluminum extrusion, and held together entirely with rivets through 1/8" gussets. (Mechanisms and vertical members are usually bolted onto the chassis.) It’s been a good pattern for us – the chassis’s construction hasn’t been a limiting factor during build or on the field since we switched to larger rivets.

On a 1-inch-wide chassis rail, we have one row of rivet holes down the centerline, spaced 0.5 inches apart. Our gussets also have holes every half-inch. When assembling rails and gussets, we put lay out the rails, put gussets on them, insert rivets into all of the gusset holes, pull all of the rivets, then flip it over and gusset & rivet the backside.

We use a # 11 drill bit ( 0.1910") for rivet holes. This allows the rivets to slide in freely, and also makes it easier to fit # 10 bolts. A 3/16" drill works in a pinch, but has a tight fit, often requiring a small socket and a hammer to push 3/16" rivets into the holes. (Maybe reamed 3/16" holes would fit better?) We also use a 3/16" drill to remove rivets.

We prefer to have a sponsoring machine shop drill the long rows of rivet holes in our chassis rails. It’s repetitive, boring work that is better-suited for CNC mills. We can make the holes ourselves on our manual mill, and usually do that for smaller mechanism pieces. Really small pieces (5-ish or fewer holes in a row) can be reliably made with a ruler, a punch, and a hand drill. More than that, and errors can accumulate to make the holes not line up.

If we didn’t have machine shops to drill the chassis rails for us, we would probably drill them by hand with a jig like this.

We used to have a pneumatic rivet gun, but we don’t anymore. During the last half of the 2019 season, and all of the 2020 season, we used this rivet tool from Menards. It looks nearly identical to the Astro 23. For 3/16" rivets, this style is much, much easier to use than more basic rivet tools. It’s so much easier that we decided to not buy another pneumatic gun – the slight difference in force and speed is largely offset by the lower price, not requiring an air compressor, and allowing us to use the same tools in the shop as in the pit. If it breaks, somebody can drive to Menards, spend $30 and be back with another one in 30 minutes.

We only have one of these riveting tools. Riveting a chassis or mechanism together doesn’t take too long; we haven’t really needed to have two.

We still keep one of the basic-style of rivet tools lying around, in case we need to re-do a rivet in a tight spot. They mostly gather dust: they’re very difficult to use with 3/16" rivets, and we’ve broken a couple of them just through occasional use.

We have a sponsoring machine shop with a waterjet make us rivet gussets during the offseason. We exclusively use L- and T-shaped gussets, usually made of (IIRC) 0.125"-thick 6061 plate. Unlike the AndyMark gussets (which our otherwise quite similar to ours), we make ours with holes every 0.5 inch, and usually put rivets in all of them. This makes 8 rivets per corner (5 holes wide, 5 holes tall, with one hole in common at the corner, and one hole being over the butt joint between the 2 rails) on the top, and another 8 on the bottom. This is almost certainly overkill, but we really don’t want our robot to split in half on the field ever again. Lighter-duty mechanisms often only get 4 or 5 rivets per gusset.

We buy our rivets from Fastenal. All-aluminum, button-head, in grip ranges from 1/8" up to 3/4" inch. By far our most common grip range is 1/4", for riveting 1/8" gussets to 1/8" extrusion. We interchangeably use rivets with 1/4" and 3/8" max grip range for this purpose. We buy one or two boxes of 500 of those before every season, and replenish other lengths on a less-frequent “as-needed” basis. Shorter lengths are useful for riveting lexan sheets. (You can use longer rivets, but they will stick out more and weigh a tiny bit more.) Longer lengths can hold many pieces together, or be used in place of bolts when you can’t access the back side of an assembly.

With a west-coast-style chassis, two of the chassis rails are capped on both ends. When you drill out rivets in those holes, the back sides will remain trapped inside the tube. If the robot is modified a lot over the season, the weight of drilled-out rivets trapped inside the chassis may actually be measurable. The robot will also sound like a rain stick when tipped on its side. If this turns into a real weight problem, (unlikely but conceivable,) a 5/8" hole near the end of the chassis rails makes it easy to shake them out.

When drilling rivets, take extra care to protect eyes and electronics, just like you’re drilling new holes in your frame. A lot of small chips will be thrown out in the process! We keep old t-shirts around to cover the robot’s electronics. After drilling, carefully fold and remove the shirt so that it doesn’t spill into the robot, then shake it out in a trash bag.

Sometimes, a drilled-out a rivet still has enough meat left on it to hold two parts together. If all of the other rivets have been drilled out, these parts can usually be pried apart. If the remains of the rivets are still stuck inside the holes, they can usually be pushed out with a new rivet, a small socket, and a tap with a hammer.

Although we’ve designed the whole robot in CAD the last few seasons, we used to build riveted-together robots that were largely “designed” by just making parts, holding them together, drilling holes through them, and bolting or riveting through the parts. I say this to emphasize that, although rivets aren’t infinitely-adjustable like T-slot is, you can still heavily modify your design after you’ve fabricated and assembled it the first time. The only critical mistakes you can make are to drill a hole to big, or to put a heavy-load-bearing hole in the wrong place such that it intersects the spot it needs to be in.

Every time you pull a rivet, the stem gets pulled off the end. My team has a tradition of collecting these in “the rivet cup” just for fun.

That’s everything I can think of right now…

Edit: It is important to put the rivets in sorta-close to straight (normal to the surface). If you’re off by too much, the pulled rivet will only be clamping on one side. You’ll be able to see a gap under part of the rim, and possibly be able to fit a fingernail or piece of paper under it. This rivet is providing less clamping force than it should be, and is more easily loosed or broken. Drill it out and put another rivet in its place, taking a little more care to ensure it is straight.


If you have expensive taste, we use these rivets. They pull flush and hold up to vibrations a lot better than normal aluminum blind rivets.

We have checked a few other US suppliers and mcm is pretty competitive, plus who doesn’t love same day shipping.


This is not the same across districts and regions. Many of these ban compressors in the pits (as my own NC District does) for noise reasons. Riveters are always allowed tools, it’s powering them that can be the problem.

One good way to overcome this is with electric rivet guns. They can be a touch more expensive than pneumatics, but they’ll do a fine job. Here’s an example from Grainger, a Milwaukee cordless.

+1 for the Milwaukee Electric Rivet Tool.

We’ve used pneumatic rivet tools for a few years, and found they are easily damaged. Once the hose is attached, it is very easy to knock it off a table (either someone trips on the hose or tension from the hose pulls it down). We had the head of the tool shear clean off on both a cheap Harbor Freight pneumatic rivet tool, and a higher end rivet tool. We got the Milwaukee M12 this past season. There is no hose to worry about, and no need for a compressor in the pits.

As an Australian, I had no idea this was a thing. Myself and @boof19 have just spent the last hour watching this channel…

Our teams use these and love it! I also use them with the shop classes I teach. They are a very nice tool and there are no air lines to trip over.

  1. Pneumatic rivet guns are nice, especially when doing a lot at a time. Ours was ~$100 and works really well
  2. We (almost exclusively) use 3/16" aluminum rivets. We also have steel and stainless too for extra strength. # of rivets depends on situation. Most of the time 4 is more than enough
  3. I haven’t used a manual rivet gun that is spectacular

Side note: Get a ton of drill bits for the rivet size you use. We have like 20+ 3/16" drill bits. They break and get dull fast, and always seem to go missing

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+1 to this. To emphasize that they’re special, we keep our 11 drill bits with the rivet tools and not with our drill bits.

Also, I’m still a fan of having a manual riveter on hand. For some jobs, it’s nice not to tie up other equipment. I like the Astro 1423 riveter for this, as it’s under $30 and it is operated with your arms rather than your grip strength.

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Somewhat topic comment here but:

We use #11 for our CNC and 3/16 for any hand drilling. Students hand drilling has enough ‘runout’ to easily put a rivet in.

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This is exactly what we do! Except we’ve been stocking 9 drill bits. Maybe 11 would be better.

AM posted a nice cross section of 3/16" rivets in .201 and .192 holes.

  1. Agreeing with others, whether air compressors are allowed varies by venue. My last team brought it to our home regional year after year without issue; then one year at a travel regional the event staff told us we couldn’t have it in our pit but we could keep it and use it in the event machine shop area if we were okay with other teams using it too. Since then I’ve been to other events where it wasn’t allowed at all. I would say it’s still worth getting even if you can’t bring it to competition. In my experience lots of students struggle with hand riveters (some just straight-up can’t do it), and the drill-attachment riveters we’ve used were kind of junky and broke down a lot. A good pneumatic riveter allows any student to rivet quickly and effectively.
  2. We use 3/16" aluminum rivets for everything, in various lengths. As for number…maybe 4-6 for most things, and about 4-6 per side for the bellypan? In general my philosophy is to put 4 or 5 rivets, put a good amount of drive time on the robot before competition, and if the rivets break either put in more rivets or substitute bolts. But the only time I can remember rivets shearing was a small part that could only fit two rivets and was part of a mechanism that was under a large amount of force from game pieces.
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