For ZZ Top's Worldwide Texas Tour in the mid-1970s, there was a live buffalo onstage, along with a longhorn steer, buzzards, and rattlesnakes. How sweet is that? I mean, wait, that's an outrage. Where was PETA? Were the animals given earplugs? I bet they were scared shitless. Or how about the guy in the front row on extremely pure pharmaceutical-grade Sunshine LSD? How was that longhorn steer lookin' to him? Animal-rights outrage aside, we can at least agree that ZZ Top have stretched the barriers of blues-based music. Boogie, swing, rock, and pop are also considerable ingredients to their Rock and Roll Hall of Fame sound. In 1983, MTV put ZZ Top's women-empowering video for "Legs" into heavy rotation, and it blew the band worldwide. "She's got leeegs, she knows how to use them." (That's empowering, right?) To date, the Little Ol' Band from Houston, Texas, has sold 50 million albums globally. Guitarist Billy Gibbons, bassist Dusty Hill, and beardless drummer Frank Beard have had hit songs about Velcro flies, sleeping bags, brothels, cheap sunglasses, and sharp-dressed men. After 40 years of making music, they've still got the pizazz, and the beards. In 2012, they released their 15th studio album, La Futura, produced by Rick Rubin. Billy Gibbons spoke from his own tour bus rolling somewhere outside Kalamazoo.

You're an ordained minister with your own line of barbecue sauces, and you've made guitars from pieces of Muddy Waters's childhood cabin to raise money for the Delta Blues Museum. Nice combo. Why thanks, I do what I can. I picked up guitar because of Muddy Waters as much as anyone. Howlin' Wolf, Jimmy Reed, T-Bone Walker, Freddie King, B.B. King, they had an impact, too, but they all come after Muddy Waters.

I had Rio Grande Mud growing up. "Just Got Paid" was my Nerf basketball anthem. How does a riff happen for you? We're fond of the endless late-night jam session. Moments happen out of moments. Where you're thinking but you're not thinking. Don't forget to hit record.

You have a Les Paul guitar named Pearly Gates. Yes, that would be a 1959 Gibson Les Paul Standard. Pearly was born on one of those days when everything was right. The wood was well balanced, the glue was right, and the electronics were built in perfectly. She was waiting underneath a bed for years.

Now it's the moment we've all been waiting for: Beard Tips from Billy Gibbons. Give us some pointers on how to keep up such frothy and sturdy plumage. A-ha [pauses]. For those who prefer to grow the chin whiskers, a good conditioner is advisable. Know you'll be separated from the millions by a personal statement and a style. Drink your beer out of a straw—otherwise, foam suds may accumulate and make you look like you have rabies. When you're playing guitar, don't get your beard caught in the strings. Ungraceful movements can occur from that. Wear your guitar low, attempt to keep beard and guitar strings apart. Accidents happen. Let your beard tell you when things are amiss.

What sort of troubles might one run into with a beard of that magnitude? Troubles come in the form of food. Scrambled eggs. Crumbs of all kinds. Watch out for electrical sockets. Items can find their way into your beard, such as bottle openers and guitar picks. On Halloween, I get compliments all night long about how I look just like the ZZ Top dude.

Have you ever fended off a charging rhino with your beard? Yes. That was the late '80s.

Have you ever woken up and found that a baby animal had burrowed in to nest while you were sleeping, like a boar? Very possibly. I like baby boars.

Has Ryan Gosling or Michelle Obama ever asked to touch your beard? I'm fairly certain both of them have.

Is it true Gillette offered y'all a million dollars to cut off the beards? Well, they deny it. That was a while ago. Even adjusted for inflation, a million wouldn't fly. Look, we're ugly, we don't want to shave these things off—we don't know what's under there [laughs].

The song "I Gotsta Get Paid" on the new album is based off "25 Lighters" by DJ DMD, Lil' Keke, and Fat Pat. How did this song and connection come about? They recorded it at Digital Services Recording in Houston in the late '90s, and we were working there, too. We got to know them and the Screwed Up Click, and that song just stayed with us all this time. We heard "25 Lighters," and you could say a fire was set. Then we figured out how to deconstruct it and transform it into the guitar-based, blues-infused song you hear on La Futura. That breakdown is something of a tribute to the great Lightnin' Hopkins, who's another one of our heroes of the Houston ghetto.

Rick Rubin produced your latest album. What makes Rick Rubin Rick Rubin? How did he capture ZZ Top? He provides a latitude that's not hurried. He's never pushy. He creates not a safety net, but a place where those happy accidents can happen. You know, those unplanned chord changes. And that kind of spontaneity isn't disturbed. He said, "Let's just start some jam sessions." Like I said before, we love endless late-night jam sessions. Rick has this Buddha-like presence that got us to dig down and do whatever we do that much better. There was no grand design in mind. The aim was to keep it simple: guitar, bass, drums. Maybe synthesizers later, or some electronic elements. But we didn't need 'em. We were having such a good time with the basic format. This is real ZZ Top. You can't lose when you choose the blues. Rick has a wide range. His Johnny Cash work is incredible. La Futura is sort of a mash-up of his Johnny Cash sensibilities and his Slayer mind-set.

Did he lie on the couch a lot? I don't think there's anything wrong with some horizontalness as long as the mind is in tip-top working order. We've known Rick for 25 years, and having him around, involved, and wrapped up in the album with us was great for all concerned.

Who's got the bigger beard, ZZ Top or Rick Rubin? We didn't get that far with it, but we couldn't help but size each other up.

With your playing, you get these tones with pinch harmonics. On "La Grange," how are you getting sounds? Roll your picking fingers slightly off the edge of the plectrum and move 'em around a little. Sounds will vary there. It takes experimentation until you get comfortable finding your sweet spots. It's a tricky thing to do, until muscle memory is dialed in. Also, with strings, I thought I had to play heavy strings until B.B. King pulled me aside and said, "Why you workin' so hard? You need to lighten up." So I started playing lighter gauge strings. I keep the tonal integrity of a bigger sound, but it doesn't have to struggle with a big string.

What made you want to play the blues? Growing up in Houston, I saw T-Bone Walker, Jimmy Reed, Albert Collins—and Ray Charles was my favorite. I was like 5 years old and I saw Elvis on TV.

Let's get into ZZ Top's spinning guitars. Y'all make it look so easy. Was there ever a time the spinning went wrong? How are you doing that, anyway? Those are our spinning fur Dean Z guitars. The idea goes back to my Moving Sidewalks days. The bass player for the Moving Sidewalks, Don Summers, thought it up way back—we used it as part of the Sidewalks' show. The guitars are attached to our belt buckles. It's a rotary electrical contact and strap mount. A hole is bored in the back of the guitar at the balancing point and the device is mounted there. Oh yeah, you gotta look out for that thing coming back around. Get your head and neck out of the way or else it'll say hello in an unfashionable fashion. Wait a few years before you jump into spinning your Dean Z [laughs]. Learn your songs first.