The Pollock "Executive" chair produced by Knoll

When production of the Pollock chair began in the US in 1965 (added to the Knoll Associates catalog in 1965), the base featured a central column and four tapered legs in chrome-plated aluminum, designed specifically by C. Pollock for this chair, echoing the contours of the seat, which was also in chrome-plated aluminum. A 1968 Knoll Associates advertisement shows the Pollock chair with its first edition base, while the 1971 advertisement shows the second version in the same background setting for photo.

Looking at the curve of the chrome trim at the top of the backrest and below the knee bend, I notice that the US versions are most of the time more curved than the EU versions of the Pollock chair. The horizontal curve of the upper backrest is less pronounced and the curve below the knees is almost straight in the early EU editions.

Two different reinforcements have been added (see image near) to reduce the force exerted by the weight of a seat between the chrome trim at knee level and the seat mounting plate. Seats v1 and v4 in the image in the previous paragraph do not have these reinforcements, which is an important detail to consider when purchasing a used chair, it's here to strenghten the very border of the seat. I often see Pollock chairs where the part of the shell under the seat has broken under pressure from use and has ended up coming out of its place, exposing the padding and making the chair uncomfortable and almost unusable. Many used Pollock chairs have this problem, which can only be repaired with makeshift solutions without changing the shell which won't last long... The option of covering the shell in leather was already offered by Knoll in that time.

The white version of the shell was produced shortly after the chair was added to the catalog, giving the Pollock chair a less office-like appearance.

The height adjustment and tilt mechanisms are mechanical, made of steel, aluminum and rubber, that's very though parts. Some of the earliest casters are marked "Knoll International", while others do not but are the same size/type. Larger casters were produced in subsequent years, they were manufactured by KEVI in Denmark (the inventor of the double-wheel caster) and were most commonly found on the first edition of the Pollock office chair. While it is more common to see it with its chrome 4-leg base, a 5-leg all-chrome version was also produced. (Early Pollock chair casters)

Most appreciated in a living room, office, around a table, for a client, for a boss, in a bedroom, near a fireplace (not too close, though), with or without armrests, it fits anywhere! A swivel and fixed version have been produced. I find fixed version practical in a waiting room or near a piece of furniture, for to makes it stay in place. The Pollock lounge chair (lower seat) has even been produced, but it is less common, especially in the US. (Pollock chair glides, 1st edition)

The Pollock ottoman was indeed marketed in the first edition, perhaps only in the EU as I haven't seen any in the US. It is less common and less in demand than the classic chair, but that's a beautiful combination. It uses the same manufacturing concept as the chair, with a shell, chrome aluminum frame, and leather/fabric cover with two tufted buttons. The mounting plate is identical to that of the armchair. However, the mounting plate for the ottoman base is horizontal, parallel to the floor. This plate has an angle on the chair base.

As I mentioned above, the 1968 Knoll advertisement features the Pollock chair with its sleek design base, designed by Charles Pollock for his chair using a costly manufacturing process. this base is twice as heavy as its competitor, Herman Miller's Aluminum Group collection (EAxxx series) designed by the Eames duo (whose base surface was not chrome-plated at the time but simply polished). A single mold was enough to manufacture all the bases for the legs of the Alu. Group series without any manual structural assembly. For the base of the early edition of the Pollock chair, the base has a chrome-plated steel column with eight threaded holes in the lower part for attaching arms, which are made of cast aluminum, followed by surface treatment to apply a first layer of copper to receive the next layer of chrome (chrome can't stick directly to aluminum), which is then polished, and finally plastic glides or casters, depending on the model, which are attached to the legs with screws! In summary, the base of the Pollock chair assembly consists of 1 column, 4 legs (8 mounting screws), 4 glides/casters (4 fastening screws), and 21 components requiring several workers to operate manually on an assembly line. For Herman Miller, the base of the EAxxx series, which performs the same function, consists of 5 components : a single-piece base made from cast aluminum and 4 glides/casters that are firmly attached and also much lighter.

According to Knoll's 1971 advertisement, the original base of the Pollock chair has been discontinued. Knoll remains silent about this, but it is easy to understand that production and assembly costs of the base are at least twice as expensive as those of its competitor. The new base model is standardized on most Knoll office chairs, now consisting of a thin steel column, four pressed steel legs simply welded to the column, all painted (some columns are chrome-plated in the US and some are painted white for the Pollock chair with a white shell), The legs are topped with a durable stainless steel element, either force-fitted (these models have a kind of "bumper" at the end of the legs) or, more often, with a thread/nut passing through both sides of the leg. The glides and casters are also standardized and are force-fitted, as Herman Miller chairs. With this new base for the Pollock chair, Knoll has reduced the number of parts to be assembled to 9 (not including the stamping and welding of the 4 legs to the column) instead of 21, with almost no screwing required. In my experience, it seems that production of the first edition base in the US wasn't maintained, but in EU yes, as I have restored some that were dated between 1970 and 1979. Today, this base is no longer in production and can only be found on used Pollock chairs.

In the previous paragraph, I mentioned Knoll's adoption of the new standardized base for a large part of the Knoll Office collection, drastically reducing production costs and abandoning the design. In my opinion, this early base contributed to the immediate success of the Pollock chair. Anyway it did not prevent it from remaining a flagship product, as its other major asset is, of course, its comfort. A few years later, the Pollock chair's reputation was well established. Knoll now offers the option of full leather upholstery for the armrests, which is a luxury feature.

After seeing numerous service returns written in chalk or marker inside the Pollock chairs that I restored, equipped with a second edition shell but with a first edition base, I concluded that the first edition shells (those with the small mounting plate), particularly n°1 & 4 (paragraph "Different shell models"), are made of a more fragile plastic and most do not have a steel reinforcement plate under the padding at thigh level (the first version of this solution was a zigzag steel rod, which was less effective than the steel plate). In summary, a reinforcement plate was added to counter the problem of the upholstery gaping under the seat after the shell gave way in that area, and a change was made to the composition of the plastic used for the shell, making it more resistant over time by also adding more crimping points for the shell on the chrome trim, which a few decades later will cause very localized breakage of the shell at the crimped areas, rarely affecting the visual appearance, but which can worsen if not repaired in time. A version with a black trim instead of chrome is available, and the stainless steel covers at the base of the legs can also be painted black.

As mentioned above, the Pollock chair was fitted with a new base between 1969 and 1971 in the US, at a lower production cost. It was less attractive in my opinion but did not affect comfort in any way.

Several variations of the base of Pollock's Executive chair appeared during this period.

This marked the beginning of numerous variations, with different models of casters depending on the US and EU versions, some still manufactured by KEVI in Denmark, others not, with hard floor/carpet glides made of painted steel, nickel-plated steel, with a white or black nylon base. Some models of these second edition 4-leg bases are equipped with a kind of plastic "bumper" at each end... You may find that these are missing on many second-hand Pollock chairs dating from this period. The swivel base version with return mechanism appears, the fixed version, the simple swivel version (the upper and lower parts of the base swivel on a ball bearing type), the swivel version with height adjustment (this model can go down quite low, which is practical near a coffee table). (Pollock chair glides, 2nd edition, Pollock chair casters, 2nd edition)

Some customers were unaware that their Pollock chair was height adjustable for this second edition of the base. It's easy to check : if the part shown on photo is present under the base, it is adjustable. It is a rather archaic adjustment system, but it is commonly found on second-hand Pollock chairs. With simple maintenance, it can remain functional for many years.

In 1980, Knoll introduced a new height adjustment system for visitor chairs. It was less archaic and more accessible, with the central column containing the system covered by two steel tubes (first period) or three plastic tubes (second period). To adjust the height, simply hold the seat in place and turn the lower tube in either direction. The three plastic tube version sometimes features a small sticker with the words "Knoll International" surrounded by arrows and + and - signs. The problem that can occur with this latter version is a gap between the seat and the base if they have been used extensively at maximum height. The base may remain on the floor when the chair is lifted, or fall when it is lifted due to wear on a nylon part in the adjustment mechanism.

The base model with casters and tilt function is very popular. This feature is always paired with height adjustment, but this version is very uncommon in the EU with the second edition 4-leg base, at least the original, non-modified version. More common in the EU is the 5-leg version, still made of steel, with stainless steel caps on each leg (Pollock chair stainless steel covers), the mounting plate on the upper part of the base is made of cast aluminum, where you can see the manufacturer's signature “Knoll International” in relief, a tilt tension adjustment screw is visible, the height adjustment system is identical to that of the visitor chair. the forces exerted by repeated tilting and the mobility provided by the casters cause the height adjustment to fail on many of the Pollock chairs I have restored, often because they have not been maintained, but after 25 or 30 years nonetheless. If you turn the chair upside down and knock the tube closest to the arms (larger diameter), or simply by rotating the base, black powder (residue from dried grease and metal) comes out of the tube, it's time to do something. If the arms no longer rotate without moving the seat of the chair, it's too late, but I can fix this problem with spare parts and restore your Pollock chair to its former glory.

During the 1980s, the second edition of the five-star base was produced, and Knoll switched to a one-piece version made of painted cast aluminum (black/white), which was lighter and had fewer welds. The height adjustment system was modified in the 1980s, and Knoll introduced height adjustment with a lever using a gas lift. Some US versions have a different mechanism to operate the adjustment, which is identical in the EU since the early 2000s. This is the most advanced height adjustment system. The original gas lift cylinder is manufactured by Stabilus (which also supplies Herman Miller for its office furniture). It is a high-quality wear part that can last some years (depending on the user's shape) before showing signs of sagging when you sit in your Pollock chair. The end of the gas cylinder system on the base (it protrudes from the middle of the base and is very close to the floor) is almost always protected by a chrome plastic cap with a sticker bearing the words "Knoll International" and safety warnings regarding the gas cylinder.

This marks the end of stainless steel covers. Knoll has adopted a new version of the base for the new Pollock chairs. All recent versions of the chrome contours are now identical to the 1965 US version (excluding special finishes, satin, and glossy black). The shell is thicker and more resistant, as this was one of the weak points of the Pollock chair. It is so resistant that the steel reinforcement plate between the seat and the shell has disappeared (see photo Pollock shell reinforcement v4). The chrome also seems more resistant to me. This is another weak point of the Pollock chair that you may notice on many used Pollock chairs. Polishing can remedy this problem, but not 100%. Although leather-covered shells and armrests are not offered online by Knoll, it is possible to have them on custom order. The current version of the base of the new Pollock chair has 4 legs for the version without casters and 5 with casters.

As soon as it was added to the catalog, both versions were offered, with or without armrests. Without its armrests, the Pollock chair has a very cool shape, and you can sit in it more easily without necessarily being in line with the seat. The armrests are made of bakelite, which should not be cleaned with a scouring pad as this may remove the shiny layer, making the armrests dull. They have two brass pins and a lug and are shaped to fit the curve of the chrome seat and backrest of the chair. Two screws pass through the chrome section to fit into the pins and hold them securely in place. The armrests have remained unchanged since the Pollock chair was first produced. (Pollock Knoll chair armrests)

When the Pollock chair was first marketed, Knoll offered a wide selection of fabrics, imitation leathers (imitation leather is no longer available, but was in 1965 and thereafter) and leathers. I have had customers who have owned Pollock chairs for a very long time and were convinced that their chairs were made of leather. It is not always easy to tell from a few feet away, but a few harmless tests can verify for sure what kind of upholstery your Pollock chair has. Be wary when buying a second-hand Pollock armchair from a photo, as the seller may not even know that it is plastic upholstery. If you have any doubts, ask for a guarantee if the surface of the upholstery is unusually smooth and clean, especially if the seller claims that the Pollock armchair is a first edition. In my experience, the most common colors are white/cream imitation faux-leather.

Until the 80s, Pollock chairs were upholstered with latex foam, molded specifically for the chair, a high-quality, durable, and high-performance filling that is not very susceptible to sagging. However, after many years of use, they harden and become uncomfortable, which is not necessarily visible in photos. So if you buy a used Pollock chair online, it's a gamble for the early ones made with latex. From the 80s onwards, the upholstery became a combination of two densities of polyurethane elastomer, which is simply the upholstery used in all modern furniture... Much less durable than latex.

This is where you can read anything and everything, but especially nonsense, such as the signature theory with a 1cm by 2cm "Knoll" sticker, or the larger paper sticker under the seat. The local printer can make you 10,000 identical ones per day. Is the mounting plate with the embossed inscription "Knoll International" on the rolling chair from a specific period an added value? No, but it is simply confirmation that this base dates from the 75-80s period, which is not a guarantee of quality because it is the one I repair or replace most often. In short, to recognize a genuine Pollock chair, it is the visual signature that works, and for this chair, it is unmistakable : it has a certain shape, curves that are its unique, true signature. Some people will claim that there are several manufacturers (which have a similar visual signature when viewed from 30 meters away in thick fog), Comforto, Strafor... this is wrong, the only manufacturer of the Pollock chair has been Knoll since 1965. Don't trust the (unverified) descriptions in online flea market ads. Look at some examples in photos, apparently authenticated by one or more experts. The only reliable expert for recognizing a Pollock chair is your own eye.

I find the term "knock-off" a bit exaggerated. There is a chair designed by Randall Buhk for SteelCase (US) in 1970. SteelCase bought Strafor, which produced it in the US. It was one of the brand's best sellers worldwide, less expensive and quite successful. Comforto manufactured a similar model during the same period and was bought by Haworth. Haworth and Steelcase are the world leaders in office furniture. The next one comes from Italy, from the company Talin, which manufactures office furniture. It bears much more resemblance than R. Buhk's model, but even so, the armrests and upholstery buttons are oversized, the proportions of the cushions are not pleasing, the outline is not a single piece of chrome-plated aluminum, but two pieces riveted together to keep the leather taut around the entire outline of the chair. The idea is good, and visually it is the closest to the Pollock chair in terms of curves.