I own sixty-eight circular saws, and that’s utter lunacy, part seven- A worm drive/ Rockwell double feature

Welcome back, everyone. Today's discussion is a double feature: we'll be covering a peculiar family and one of the few times Porter-Cable followed someone else's lead, the worm drive saws, and wrapping up the family tree with the last of the Mohicans, so to speak.

Porter-Cable started out as a jobbing company. In other words, you could ( if you were alive 114 years ago) go to the firm with a set of drawings under your arm, walk up to the sight of George Porter pigging out on a baby carrot, and have a widget made to order. The company made any number of non-tool related items, from pencil sharpeners to automotive steering wheels, but they were mainly manufacturing metal lathes and milling machine attachments ( and forging the occasional vise) until the hiring of Arthur Emmons, a young fellow who would prove to be the most prolific power tool inventor of all time. As I have previously mentioned, this bright young fellow would invent the portable belt sander and the first helical geared circular saw, the K-9 ( the K-8 was of similar appearance but had no gearing at all, being directly driven). Porter-Cable president Walter Ridings knew a good thing when he saw it, and the company made some genuinely great sidewinder saws, as we have seen. The day would come, however, when Porter-Cable would try their hand at making a line of worm drive saws. Not small trim saws, like the well-regarded A-4; these machines would be intended to compete ( East of the Mississippi, at least )with the Skill 77, the original hand-held circular saw design. I'm speaking of the 533, 567, and 568.

Left to right: 568, c. 1963 , 533, c. 1960

In 1959, Porter-Cable introduced the 533. A worm-driven, pivoting foot left-hand circular saw, it owed much of its design to the extremely popular Skil saws of the past thirty-seven years ( I'm not sure who was responsible for drawing up the plans, but they definitely looked over Skil's shoulder, a far cry from the times when Skil had to pay royalties to the NY boys in order to make the A and B belt sanders). The blueprint was followed so closely that some Skil saw parts, such as adjustment knobs and even the base, can be persuaded to fit the Porter-Cable. The Porter-Cable differs only slightly, being made with off-the-shelf bearings and seals, making rebuilding less of a task. The 533 is a bit stouter in some aspects, but the two saws are neck and neck in terms of performance.

By 1961, the 533 had been supplanted by the 568, which differs in being slightly slower and a half pound lighter and being one of the first saws to adopt the beautiful, exciting putty gray and satin black painted finish Rockwell would slather on any number of tools in following years to avoid firing up the buffer. The family would be rounded out with the addition of the 567 in 1964. This saw used a 6 3/4" blade and was a bit lighter still, but the three saws are very closely related, diverging only in scale and finish.

On the whole, the three saws are excellent machines, very rugged and plenty powerful, but they didn't do anything that the contemporary Skil saws couldn't do better, and even though the 567 and 568 were on the books up to the Pentair buyout of 1981, they just weren't that popular. They remain a curious decision on the part of a company that had no business deviating from the role of trailblazer.


It's time to conclude our brief history of Porter-Cable/Rockwell circular saws. There are a number of places we could end the story; when Rockwell purchased the company in 1960 or when the last saw to feature a grease cup ( the 315-1 and its ilk) debuted in the late '70s. For my part, I'll stop in the middle, with the last aluminum-bodied saw to be introduced and the standard bearer for future generations of users. Let's look at the remarkable 315, or (as I think of some of the examples that have come through the shop) the saw of Theseus.

Appearing in the April catalog for 1964, the 315 was the bare bones version of the well appointed 597, which was itself the logical evolution of the highly successful 115 platform. The castings are tumbled rather than polished, lending them an "orange peel" finish, and the fit and finish is not as precise ( the castings are designed to allow for some misalignment, making the 315 an easy saw to Frankenstein back together from multiple donor saws). Accuracy and power are still respectable, and the wraparound base, inherited from the 115a provides plenty of support, although it precludes cutting up to a vertical obstruction, such as making a pocket cut for a floor grate near a wall. The 315 has two sister saws, the 346 that debuted at the same time, and the larger 368, welcomed into the fold later that same year.

The 315 and company have a few minor faults. The two wrench system of the 115 has been retained ( somehow, people always lost the jackshaft wrench- they are now lost to the ages like all the Unisaw dust doors), which is a bit awkward, and several saws left the factory with a base that does not properly align with the cut, making it difficult to saw to a line without a guide; I've seen too many examples with this problem for it to be anything but a manufacturing fault. The only other real issue is the tendency of the handle to bow under the repeated stress of being used to push the saw, resulting in a noticeable gap between the outer handle half and the handle base. This is due to the lighter castings and is an issue shared with all of the saws in this family ( the 315,346,368, 596 and 597).

As I said earlier, the 315 had a sort of harbinger in the form of the 596,

and the larger 597, which first arrived on the scene in early 1963. These saws are the deluxe version of the same concept. These two saws differ in having more powerful motors, a mechanical brake that worked against the fan ( a larger, cast aluminum affair with a pronounced outer rim) , and a sort of micrometer adjustment for depth. The 315 would share the same basic castings ( although the handle is different, not having provision for mounting the brake button and linkage) , and the later 368 would use the same armature as the 597, but if the 315 is a base model work truck, the 597 is the version with powered windows and heated seats- it's a very luxurious saw, at least in comparison to the more spartan 315.

There are variations of the 315, but they're limited mainly to cosmetics ( and the fifteen-minute window when the saw was known as the 215, for reasons only Rockwell understood). The basic design was by far the most popular saw Rockwell would ever make, being constructed for thirteen years, and the 315 survived in enormous numbers due both to being a durable design and being easily repaired; there are saws brought into our shop for repair that have had every single part other than basic hardware replaced over the decades, a testament to how well-liked the design is. For my part, the 315 is the P.C/Rockwell tool I have the most experience with- I've probably repaired or rebuilt seventy or eighty of them in my time, and my boss, Dave, has likely worked on hundreds of them. To this day, I still regularly see them, almost always in the hands of someone 40 or under who inherited them from their father or grandfather. It is a comforting thought that the remarkable bloodline of innovative, robust, hardworking saws that stretches back to the brainchild of a twenty-five-year-old named Art Emmons still commands some respect, even now.

The 315 is often considered to be one of the best circular saws ever made, and are so sought after that I've had every 315 I've repaired for myself begged from me over the years- it wasn't until fellow OWWM'er Mike Levine sent me this example that I stopped allowing myself to be talked out of them! Personally, I would argue that there are far better machines in the family, with more power, greater accuracy, and better looks. That said, nothing succeeds like success, and the 315 was a highly successful design.


Later designs would be developed to make a double insulated version, known as the 315-1, a good saw in its own right but as dull as a beige living room. The artistry of the power tool ( for me, at least) did not survive the transition to plastic, making the 315 the last of a very distinguished family.

Our saws:
533: 4,500 rpm, 7 1/2" blade, 17 1/2 lbs
567: 4,800 rpm, 6 3/4" blade, 14 lbs
568: 4,200 rpm, 7 1/2" blade, 17 lbs

596: 5,800 rpm, 6 3/4" blade, 14 lbs
597: 5,800 rpm, 7 1/4" blade, 14 1/2 lbs
346: 5,800 rpm, 6 3/4" blade, 12 lbs
315: 5,800 rpm, 7 1/4" blade, 12 1/2 lbs
368: 5,250 rpm, 8 1/4" blade, 13 1/2 lbs


Epilogue- when I started this thread, I thought I was being a bit obsessive about collecting Porter-Cable power tools. Today, I know I am. I've had a great deal of enjoyment in doing so, from the thrill of the hunt and the challenge of resurrecting some truly rough examples, to the gratitude for the efforts of fellow OWWM members in helping find so many of the missing puzzle pieces ( many of my most prized workers were not the result of my vigilance; rather, a number of them were handed to me, almost on a platter).

I currently am the owner/caretaker/foreman of 57 circular saws. Some of them were purchased by home handymen and barely used; others bought by contractors or industrial concerns and used to hell and back. A few of them served their countries, like my USAF K-89. All of them are highly prized, carefully used, and lovingly maintained. I will probably never have an example of every saw, and I've come to terms with that ( but I'll still going to try).

There are 12 known saws that I have yet to find:

K-8
K-9
K-12
K-65
Kwik saw
168a
76
177
567
592
597
597a


Some are hen's teeth, and some are inevitable finds. A few are legendary, and some are notorious. All are fascinating components in a very long story of one company's influence on how work has been done for decades. I'm hoping I've given some explanation of why I find them so interesting, and perhaps you'll find them interesting, too.