In this installment of the Drafting Table Quarterback, we have a side-by-side comparison of two products near and dear to any design student, homeowner or design professional: Two 18v cordless power drills. We picked these Ryobi P271 and the Makita XPH012 not because they are the most popular or highest rated. We selected two entry level products, not made by the same parent company. Sorry Black & Decker, DeWalt and Porter-Cable, as much as I wanted to peel back the housing and prove my assumptions that despite the price differences and styling, there is no real difference your 20v drills, we were afraid that beyond that bit of gotcha journalism, there would not be much else to talk about. There may have been other, even better, options but we thought these would provide two varied looks at the same product segment.
In full disclosure, I own a Ryobi Cordless Drill, live 30 miles from their office in Anderson, South Carolina, and even interviewed for a job there 17 years ago. Are any of these factors coloring my opinion in this article? Absolutely. I am a designer, not a journalist. That's also part of the fun.
I know what you are thinking, a drill is a drill. Did you really need to tear apart two of them for this article? On some level, that is true. A drill is a drill. They share a lot of the same approaches and even the same components. They both use Samsung batteries. They both share a basic configuration of a pistol grip balanced on either end by a battery and motor. They both use a traditional chuck that was likely purchased from a 3rd party. They both have a decent center of gravity that doesn't add undue stress or twist on your wrist or arm. Neither are game changers either. They are members of the orchestra assembled by their respective companies. They are just company 'tools' towing the corporate line. That orchestra plays a big part in the design.
STYLING
If you haven't noticed, power drills have an inferiority complex. They are not often seen clad in the all-metal housing of their forefathers. They are plastic, either ABS like the Ryobi or glass-filled polycarbonate like the Makita. They still want to be taken seriously and designers go to great lengths to convince buyers that they are not buying a toy.
Makita XPH012 18V cordless power drill The styling of the Makita is bold and aggressive. The TPE is used to dynamic effect as if to wrap the drill in a protective exoskeleton. Pretty is not a word I would use to describe it, nor is beautiful. It is a masculine tool that requires masculine adjectives. Does all this styling make the tool better? No more than Mike Tyson's facial tattoo makes him a better boxer. But I would not dismiss either one.
The Ryobi drill is not as aggressive. I would more say that it is strong (and a little flamboyant) but still approachable. This fits well with its target market. It is designed to make people who are not experts feel good about buying their tools. There is a certain amount of bolstering in both tools. I would not go as far as to say they are being dishonest. Each generation of these tools has to yell louder and push the boundary further.
On the left the Ryobi 270G. On the right the Ryobi 271. The Ryobi P271 is a near dead ringer to my personal Ryobi P270G that I bought several years ago, so much so, that I could not help but place them side-by-side and do a little mini evaluation. No, I didn't take mine apart. I don't need 3 broken drills, thank you. But even on the surface, there are some interesting changes that have taken place since that original purchase and much that is familiar. I first bought a Ryobi drill 15 years ago. When the NiCad battery sucked it's last electron a few years back, I wandered into Home Depot on my lunch hour for a new battery. There I found two options: Buy a replacement lithium battery for $80 or a new Ryobi drill, two lithium batteries and a charger for $99. I chose the latter. Although, I went to art school and didn't study economics. The buying proposition was simple: spend $20, get two batteries and a new "Baby Poop" green drill as a backup to my much older Ryobi Drill.
BATTERY
I bring this up because it leads me to my first design consideration. Ryobi has an extensive collection of battery-powered tools that share the same battery. When they changed battery technologies, they made sure the new lithium batteries were compatible with their existing lineup. I owned their drill, flash light and near-worthless battery-powered chainsaw. And when given the chance to run away, I doubled down. Being reverse compatible won them a sale.
On the left, Ryobi's reverse-compatible battery features a hollow connector post. On the right, Makita's sliding battery. Every other manufacturer, including Makita, changed their connectors. Maybe they had less invested in this idea of a family of tools with a shared power source. Keeping the same style battery connector with a hollow connector post affects the design of every cordless tool Ryobi makes. Love it or hate it, I doubt they are going to change it now. Which is great for consumers with tools that outlived their batteries, but likely a pain-in-the-ass to design around.
The Makita uses a similar connection method to other manufactures where the battery is slid on from the front of the drill. I am not sure if this is correcting an engineering flaw or just good UI. The Makita battery has this little red printed strip on the battery release. When you attach the battery from the front, there is a point where the battery makes electrical contact but is not completely locked onto the drill. Tip the drill forward and the battery will slide off. The red warning stripe is there to alert you of this condition. When the battery is locked in place, the red stripe is hidden. The Ryobi avoids this by having a battery that is connected from the bottom. If it is not mechanically connected, it is not going to stay on.
CONSTRUCTION
Cordless drills all have a similar construction. There is a power source (battery). A reversible variable actuator to manually control the amount of power applied to the motor (trigger switch). There is a gearbox that allows the drill bit to spin at a much slower rate than the motor. Both the Ryobi and the Makita have a 2-speed gearbox. That adds an additional set of planetary gears and a switch on the top that engages and disengages these gears. They are engaged by a plastic ring in the gearbox that slides in and out of position by the switch.
Ryobi 2 Speed Gearbox At the end of the gearbox is a clutch that can be adjusted to limit the torque provided by the motor. Attached to the clutch is the chuck. This is the part that holds the bit (or apple) in place. Most every chuck is based on the same design. Back in my day, drills used a key system to tighten the bits in place. I remember some of my earliest experiences with a drill and losing that key. It was not long before I would not bother looking for it, grip the chuck in my hand while applying power, using the friction to tighten the bit. I mention this because I am certain at some point, a designer realized that no one uses the key and have all adopted the "friction lock" method I described. Almost every time I use a drill, I am reminded of difference between design and user experience, and the value of understanding how your product is used by real people.
HOUSING COMPARE
A three-part housing design supports the rear motor bearing on the Makita drill. Makita boasts of a shorter length and lighter weight which led them to design a three-part housing versus the simpler two-part clamshell of the Ryobi. At first blush, I took this three-part housing as a design decision to allow for a well considered vent pattern on the tail end of the drill. I briefly applauded the designers' ability to get engineering buy-in on this moment of design excess. Upon pulling apart the housings and comparing the Makita to its dissected counterpart, I realized that Makita integrated the housing of the drill and the motor housing. That third part added to the design includes a molded detail to support the rear motor bearing and is key to reducing the size and weight of the product. Ryobi's motor is completely entombed in a metal cylinder that is not conducive to non-destructive investigation and by comparison is HEAVY and BIG. It is both obvious and hard to say which solution is better.
Makita wins the engineering award when it comes to solving the weight challenge. It is kinda "futzi" to put back together and makes a pretty high pitched annoying noise compared to the sound deadening effects of the heavy metal can that seals up what is likely a very similar motor. The Ryobi has to be easier on those tasked with final assembly and it likely allows for the company to outsource the motor assembly and still test the incoming parts without first building a complete drill.
The clamshell design of the Ryobi housing. I say it is obvious and hard, because I can easily justify Ryobi's choice but have also suffered through far too many experiences—holding that heavy-ass drill in some awkward position or trying to squeeze it into a place it had no place being—to accept my own justifications. So much so that two months ago I bought a 9V Ryobi drill with a LED light for such situations.
TOOLING
Co-molding plastics and TPE have some production limitations but can also generate some interesting design details. The TPE is molded directly on the plastic part. This requires the tooling to have two cavities. The plastic is injected into the first cavity—once cooled the plastic part is removed and inserted into the second cavity. On the outside of the drills is a recessed line that separates the areas covered by TPE from the areas not covered by TPE. This is where the tooling seals against the plastic part of the drill. Having this moat helps hide any marks. They are still there, just less obvious.
The recessed line on the outside of the drills helps hide where the tooling seals against the plastic part of the product. This process fuses the materials together fairly well but engineers still use methods to mechanically fasten the two materials together. The engineers devised a dovetail styled joint to keep the two materials from coming apart. In most cases, it is best to keep the TPE connected to create a single form so that it can be injected from one location.
Detail showing the mechanical dovetail joints that secure the TPE to the ABS Hidden channels to connect the TPE over molds on the Makita housing The Makita uses some neat tricks to make this happen but the rear housing has three injection points. TPE is a little more forgiving when creating forms with variable thicknesses than ABS plastic, but thicker parts do require more cooling time in the mold. If you were designing a toothbrush, the product cost is not in materials but cycle time. The faster you can open and close the mold, the cheaper the product becomes. A power drill is no toothbrush (that should go without saying) but undoubtedly keeping the cycle time down on these parts is a definite design consideration.
There are a lot of great reasons to want to know if a consumer has been peeling back the plastic housings of the product that you worked so hard to design and manufacture. There are obvious warranty issues but there is also the issue of swapping out consumables and broken parts from newly purchased items and then returning them with internal bits from an earlier purchase. Spending five minutes unpacking an ink cartridge will express the lengths manufacturers will go to stop you from "creative shoplifting."
In cordless power tools, batteries represent the ink cartridge. Both drills employ a similar tactic by press fitting a piece of plastic in one of the screw holes on top of the screw. You can't remove the screw without removing the plastic and you can't remove the plastic without destroying it. Ryobi also used security screws with a post in the middle of the torx head. Once inside, the Ryobi drill's battery assembly is fairly easy to disassemble if one were so inclined. They are readily available online.
Makita uses security screws but chose an assembly method that I am pretty sure will result in things not going back together again. My first thought was that they are making it really hard to recycle this battery, sure you can tear it apart, but there is definitely not a reuse option. Again, they want you to buy a new battery pack with a huge profit margin, not refill the one you got with batteries bought wholesale.
ASSEMBLY
If you have ever visited a modern factory, you will see rows and rows of people completing small tasks and passing the product down to the next person in line. To do this and not make a mess, the products are mounted in fixtures to hold them in place while carrying them on their journey. You cannot underestimate the importance of fixtures in manufacturing. The less a product is lifted and man/woman-handled, the better.
When you look at the two main housings of these drills, you will see a side with screws and a side without. By putting all the screws on one side, this frees up the other housing to be used as the first component in the assembly process. With the right housing placed in a fixture, the drill can be passed from station to station, each person adding a different component. An interesting point to note is that none of the parts are screwed to the housing. Each part is placed by hand in the housing with molded details that hold them in position.
Once all the parts are in place the two housings (three in the case of Makita) are screwed together sandwiching the parts securely in place. The value of putting all the screws on one side of the house is two-fold. Yes, it makes assembly easier, as they are all accessible without moving the tool. The other thing it does is give you a side with seemingly randomly placed holes and screws and one that is pretty enough to photograph.
Conclusion
There are many more things that I could point out on both of these products. Whether it is drop testing requirements, motor ventilation or Marketing's push for bigger logos and bolder colors, these details and more were debated, reviewed and agonized over. Consumers often overlook them, but we don't.
What should we teardown next? We need you to do the scouting report.
Leave your ideas in the comments or tag a product with the hashtag #draftingtableQB and we'll consider your product for our first round pick.