SDS Plus vs SDS Max – Understanding Concrete Drilling, Chipping & Demolition Tools

Remember back when there was just “USB”? Now there’s USB-A, USB-B, USB-C, USB-2, Mini-USB, Micro-USB (not to be confused with Mini-USB), and of course, USB-3. Simple, right?! Thankfully, the world of concrete drilling, chipping and demolition is a bit simpler. Simpler, but still with enough variations to confuse most people that don’t deal with concrete everyday. In this article, we’ll dive into the differences of SDS Plus vs SDS Max, two of the more common standards of concrete drilling and chipping tools. In the process, we’ll also get into the tools that drive these bits, and when you might want to reach for SDS Plus vs SDS Max, and vice-versa. Let’s get ready to make some silica dust (to be promptly vacuumed in an OSHA-compliant fashion, of course)!

SDS Plus vs SDS Max – The Basics

When it comes to concrete drilling and chipping tools, most of what you’ll see out there are SDS Plus and SDS Max. SDS Plus also sometimes uses “SDS” (no “Plus”), however both SDS and SDS Plus can be used in the same SDS Plus tool. Sometimes you’ll run across Spline tools and bits. They’re similar to SDS Max in terms of size, but there are more SDS Max bits and tools out there. If you are investing in a beefy concrete drilling or chipping tool, we’d recommend something using SDS Max vs Spline – mainly because you’ll have more accessories to choose from with SDS Max.

At the most basic level of SDS Plus vs SDS Max, SDS Plus bits are thinner and smaller than their SDS Max counterparts. I’m going to get all crazy metric on you and lay down these stat’s; the diameter of SDS Plus shanks are 10 millimeters, with the beefier SDS Max shanks at 18 millimeters. SDS Plus is lighter duty and for smaller holes when drilling, SDS Max is heavier duty and for larger holes.

When you’re evaluating SDS Plus and SDS Max tools, you’ll find they tend to have either one, two or three capabilities. The tools with drill only modes function like you would expect a drill to in that mode, with rotation only. Rotary hammer drilling mode combines the rotation with a hammering action that gives the concrete at the end of the hole repeated little Hulk smashes, while the rotation also helps extract the concrete debris. Finally, chip-only tools are all about chipping away or breaking up concrete.

Most of the SDS Plus, and some of the SDS Max tools have drill only, hammer drilling, and chiseling modes. The remainder of the SDS Max tools and what are referred to as demolition hammers (or demo hammers) only have a chiseling mode. If you’re a homeowner, doing lighter duty work I think a three mode SDS Plus tool is great to have on-hand. If you’re doing heavier duty work or demolition only (meaning you don’t need to drill holes), then a beefier SDS Max tool or demo hammer may make the most sense for you.

Is a Regular Hammer Drill Enough?

At the risk of confusing things a “bit” further, hammer drills are also used for concrete drilling. If you’re a homeowner and only drill occasional, very small diameter holes into concrete you might get by with a hammer drill. They use conventional bits, and they have a normal chuck. This means you have to tighten down the chuck onto the bit. One of the advantages of SDS Plus and SDS Max bits is that they securely slide right into the chuck without the need to tighten them down or re-tighten them.

SDS Plus vs SDS Max Bit Sizes For Drilling

According to Wikipedia, “The SDS bit was developed by Hilti and Bosch in 1975. The name comes from the German “Stecken – Drehen – Sichern” (Insert – Twist – Secure).” We’re really glad they came up with an abbreviation for this, because saying “Stecken, Drehen, Sichern Plus” and “Stecken, Drehen, Sichern Max” in our best German accent would have gotten old pretty quickly. We have also seen SDS referred to as “Special Direct System” and “Slotted Drive System.” Let’s just stick with SDS, OK?

According to our friends over at Bosch (who supplied us with a couple of the tools shown in this article), the following sizes apply to SDS Plus, SDS Max and Spline. To clarify, these sizes are referring to drill bit diameter, and not the shank size.

• SDS-plus: 3/16″ – 3/4″
• SDS-max: 1/2″ – 1-3/4″
• Spline: 3/8″ – 1-3/8″

Core Bits for Bigger Diameter Holes

Bosch SDS Plus hammers can handle carbide-tipped core bits from 2-1/2″ up to 3-1/2″, and SDS Max hammers can handle carbide-tipped core bits from three inches up to 6″ and thru-hole bits up to 3-1/8″. The exact size core and thru-hole bits are dependent on the hammer size and whether the core bits are thin or thick walled. With all that said, if you’re in the habit of drilling 3-6 inch holes through concrete, you probably want to start looking at a heavy duty dedicated core drill.

Additional Uses for SDS Plus and SDS Max

There is more to SDS Max than just drilling and chipping. One sometimes overlooked use of SDS Max tools, is digging. Just about all of us have faced a home improvement or jobsite digging task where the soil we are excavating feels like concrete. Hardened soil, clay soil, and pretty much any undisturbed soil that isn’t sandy or loose can be a challenge to dig with your typical shovel. Landscaping is hard enough even under the best of soil conditions.

On a recent landscaping makeover, I used my Bosch SDS Max tool so much it began to feel like an extension of my body. Just a few tasks I threw at it included: breaking up a stucco wall, drilling holes in ridiculously hard soil to predrill for bender board stakes to be hammered in, excavating recesses for landscape boulders to be positioned in, digging trenches for pvc irrigation lines, and digging out portions of sloped yard for planter areas. The crew working on our concrete block wall project relied heavily on an old Makita SDS Max demolition hammer to dig the area for the concrete footing.

Using an SDS Max tool for digging involves getting a spade bit for the tool, which is also sometimes referred to as a clay spade. Due to the weight of the SDS Max tool itself, the last thing you want to do is use it for a shovel. For one thing the spade bit is a lot smaller than most shovels, and and SDS Max tool with a spade bit probably weighs 20x the weight of your shovel.

Most of the time I was digging with the SDS Max and spade bit, I would “cut” the outer lines of the area I was digging in, and then break up the soil in between those lines. Once things are nice and loose, it’s much easier to come in with a shovel (usually a square shaped transfer shovel) to dig out the soil the old fashioned way. Digging is never easy, but an SDS Max tool and spade bit can take a good chunk of pain out of the project, and is typically much faster as well.

Aside from drilling, chipping and digging, a multitude of other accessories are out there for SDS Plus and SDS Max tools. From tamping tools that help you compress soil to SDS Max Ground Rod Drivers for, you guessed it, driving ground rods into the ground, these tools coupled with the right accessories make them versatile for projects that don’t involve concrete. Accessories aside, how do you know when to reach for SDS Plus vs SDS Max?

When Do You Want to Use SDS Plus vs SDS Max and Vice Versa?

Ideally, the best way to get a sense of these tools is to have two of them side-by-side and then task them with the same drilling and chipping tasks. Most of us aren’t usually faced with that kind of time, and we don’t always have both types of tools readily available. My own learning curve came from quick realizations that I didn’t bring the right tool for the job. Or, as Sean Connery would say, I brought a knife to the gunfight.

On one project, I was demo’ing what I thought was a pretty flimsy, ancient concrete block wall. Foolishly, I thought my SDS Plus tool would power through it, but within seconds I could see the chipping action was doing nothing to this wall. I stepped things up to an SDS Max tool and it definitely broke the wall apart. If I had a jackhammer handy, that probably would have cut about 75% off the time I spent even using the SDS Max tool.

There are times where too much power is no bueno too. We had to have the top several feet of brick on our fireplace demo’d and rebuilt. That job was two stories up in the air, with lots of interior plaster, tile work and other construction materials that, unlike the Beach Boys, don’t appreciate good vibrations. Our mason used only SDS Plus tools to surgically remove the bricks to minimize the risk of damaging the house around the work area (and the parts of the chimney we didn’t want to demolish).

In another example of SDS Plus vs SDS Max, I wanted to clean up the rough concrete edges around a concrete pad. I didn’t want to break up the pad itself, so I chose SDS Plus to more gently chip off the rough section of concrete.

Choosing SDS Plus vs SDS Max becomes pretty apparent when it comes to drilling. If you’re doing repetitive work, especially with larger diameter holes, there’s no question the SDS Max tools are going to be much more efficient and productive for you. If you start drilling and make steady progress with your SDS Plus tool, you’re probably in good shape. If instead of progress you feel as if the drill bit is going nowhere and sweat begins to drip heavily from your brow, then it’s probably time to kick it up a notch to SDS Max.

SDS Plus vs SDS Max vs BOJ (Big Ol’ Jackhammer)

Sometimes, even SDS Max isn’t enough brute force. If you are breaking up a patio, concrete stairs, or really any area that encompasses more than a couple square feet of concrete, you should definitely be reaching for a jackhammer. Most of these use 1 1/8″ hex bits designed to take some pretty heavy abuse. For concrete demolition, usually a pointed bit or a chisel bit are used.

A jackhammer can breeze through even the most stubborn, high PSI concrete. If you have a relatively thin layer of concrete (less than 6″ or so), a good jackhammer can have you taking your after-project break with a frosty beverage in no time. The three biggest downsides to all this power and brute strength are, 1) They’re expensive. 2) They’re heavy. In fact, most come with their own handcart to transport them. 3) They are not surgical. If you’re working around delicate surfaces nearby, or you’re trying to leave a portion of the concrete intact, it’s easy to get carried away with a jackhammer.

A Word or Two About Silica Dust

Whether you are a weekend warrior DIY’ing your next home project, or especially if you are a concrete or construction professional, it’s important to be aware of the dangers of silica dust. OSHA standards require professionals to comply with their Silica Dust Standard, and DIY’ers should take precautions to to avoid inhaling the stuff too.

Cutting and grinding concrete produces the most gratuitous amounts of silica dust, but that does not mean you should not worry about the relatively smaller amount of dust drilling and demolition produces. The two biggest weapons in the battle against silica are going to be a dust collector and dust collection accessories for your drilling. We covered some of Bosch’s unique Speed Clean hollow core bits previously, but just about all the major tool brands have dust collectors and accessories designed to capture and contain silica dust and keep you (and those around your work area) breathing easy.

Maximizing Your Results with SDS Plus vs SDS Max Awareness

At the end of the day, these tools are all designed to make your job easier by getting you the results you want, as efficiently as possible. The old adage about “Having the right tool for the job” most definitely applies to concrete tools. After all, concrete is hard stuff that’s designed to stand up to time and the elements. Bending concrete to your will isn’t easy, but it shouldn’t be a completely uphill battle either.

When it comes to SDS Plus vs SDS Max, and even jackhammers, my general advice is it’s better to be over-equipped than under equipped. That general advice is especially relevant if what you are doing is concrete demolition. A task that might be doable with SDS Plus in 30 minutes is in some cases a task that can be cranked out in five minutes with an SDS Max tool. Or a task that feels impossible with an SDS Max tool, can be a quick job with a jackhammer. If you find yourself sweating and cursing more than usual on your next concrete project, make sure you grabbed the right tool! We hope this article helps you get pointed in the right direction and gives you a better understanding of SDS Plus vs SDS Max tools. Now go Hulk-smash (or gently chip) some concrete!