Summary A 1957 Gillette Tech in great condition was photographed and measured. General measurements (mass, length, center of mass, etc.) were made and safety razor parameters (blade exposure, guard span, blade angle, etc.) were analyzed. Blade alignment of the Gillette Tech is very good, but the blade tab overhang makes assembly and disassembly uncomfortable and dangerous without protection The knurling on the handle is shallow and does not eliminate slip Blade rigidity is very good, especially around the baseplate clamping supports Reverse shims were used to decrease the blade exposure to approximately zero and improve the Gillette Tech's performance for my face and neck, but the larger guard span still produced too much drag and irritation, making the razor too aggressive for me Introduction The Gillette Tech was the first Gillette razor having a solid safety bar rather than an open comb guard. Many variations of this three-piece double-edge (DE) safety razor were produced over several decades, making the Tech one of the most common vintage razors available today (URL). The specific model reviewed here was made in the United States in the second quarter (April to June) of 1957, as denoted by markings, including those for the date code of C-2, on the bottom of the baseplate. This razor is made of brass and is nickel-plated with "Gillette" etched on top of the cap, and as with many or most Techs, it has a ball end on the handle. This classic ball-end Tech is believed to be functionally representative of Gillette Techs, which are generally considered to be "mild" in aggressiveness (URL). Even though I ordered this razor through eBay on February 9, 2018, it was not until recently that I photographed, measured, and used it. This is my fifth DE safety razor and my first vintage razor. However, as discussed below, it did not become my new daily driver. Beautiful Little Razor The Gillette Tech was thoroughly cleaned, polished, and sanitized before I received it. It is in great condition, both mechanically and cosmetically, with only some minor surface issues, including light scratches, but without any wear of the nickel plating. It almost looks like new. It is a beautiful little razor. As pictured below, the cap is nicely etched, the guard is finely grooved, and the handle is lightly knurled with an attractive ball end. Measurements of Razor without a Blade Below is the general table of measurements for the razor without a blade. Mass was measured with a calibrated scale having a 0.01 g resolution and distances were measured with a calibrated digital caliper having a 0.01 mm resolution. The center of mass was found by carefully balancing the razor on a relatively thin edge of folded paper at the critical location marked on a piece of tape on the razor, measuring the distance with the caliper from the bottom of the razor handle, and then calculating the location from the top of the razor. Regarding the cap and baseplate, width dimensions are perpendicular to the guards and length dimensions run parallel to the guards, as observed from the top of the razor. The baseplate channel length was calculated using measurements. 1957 Gillette Tech DE Safety Razor: Measurements without a BladeMass58.90 gLength82.30 mmCenter of Mass from Top30.33 mmHead Height7.99 mmHandle Mass36.47 gHandle Length76.05 mmHandle Diameter, Minimum Near Top6.15 mmHandle Diameter, Maximum9.68 mmCap Mass11.39 gCap Width19.28 mmCap Length40.79 mmCap Height, Excluding Center Pin and Bar4.19 mmBaseplate Mass11.04 gBaseplate Width25.11 mmBaseplate Length40.88 mmBaseplate Height5.38 mmCenter Pin Diameter at Blade4.74 mmBar Width at Blade2.03 mmBar Length at Blade35.11 mmLengthwise Spacing between Corner Pins37.40 mmCenter Clamping Support Length3.93 mmChannel Length13.14 mmWidthwise Spacing between Channels17.95 mm Analysis around Blade Cutting Edges The methodology that was followed for determining parameter values around the blade cutting edges (URL) of the Bevel DE safety razor (URL) was applied here, but slightly improved and adjusted for the specific geometry of the 1957 Gillette Tech. The following overall procedure was employed: Measurements were taken of the cap and baseplate, as tabulated above, with care taken to make measurements that would help with analyzing parameters around the blade cutting edges The razor was loaded with a nominal 21.96 mm wide blade and the distance between cutting edges was measured as 21.60 mm using a calibrated digital caliper Using my accurate set of micrometer-measured feeler gauge blade combinations (URL), blade gap was accurately measured on each side of the razor to a precision of 0.01 mm by finding the thickest feeler gauge stack that fit at most places between the guard and the blade cutting edge with room to spare. The very even blade gaps were found to be 0.58 mm and 0.60 mm for an average blade gap of 0.59 mm. The blade gaps may be slightly higher around the middles of the cutting edges due to the middle baseplate clamping supports raising the cutting edges slightly, but the differences are minor. An investigation was conducted for measuring the neutral blade width, the blade width that causes zero blade exposure. Since even the smallest blade width (21.73 mm) from my reference blade catalogue caused positive blade exposure when the blade was shoved over to one side or the other, I was unable to physically measure the neutral blade width. A digital camera was set up for closely photographing the razor from its side. Wooden stands (URL) were used to vertically hold and easily adjust the placement of a metric scale and the razor. In particular, razor height was fine-tuned by raising and lowering the razor within its wooden stand, which helped with aligning the blade cutting edge height with the center of the camera lens. Aligning the blade cutting edge from the top was aided by a lined notecard that was taped into position such that one of the lines was in the vertical plane running forward from the center of the camera lens. Moving the razor into position is relatively easy compared to setting up the camera with wooden pieces, painter's tape, and small thin right-angle acrylic pieces to have the camera looking forward at the right height. The setup included hard stops for the camera to be repeatedly placed in the same position after rotating it up, taking out the memory card and/or battery, putting back the memory card and/or inserting a full battery, and rotating the camera back down into place. Close-up photographs were taken for analyzing parameters around the blade cutting edges, as shown below. After manually adjusting the camera's white balance, a bright secondary light was held close to the razor to highlight desired surfaces and provide a backlit background. Photographs were taken looking down a flat plastic piece against a cutting edge of a nominal 21.96 mm wide blade for quantifying steep and shallow shave plane angles, and the normal blade was replaced with a shim for capturing the neutral shave plane. Standard photographs looking down the blade cutting edges of a nominal 21.96 mm wide blade were also taken, as pictured below, but they were not used in the analysis because such photographs have been proven to be inferior. A blade modified for excessive exposure was used for better capturing of the blade plane, and with that same blade shifted over for zero blade exposure, a small metric scale was balanced on the razor and photographed for measuring neutral guard and cap spans. Mean (average) dimensions around the blade cutting edges were found using physical and digital measurements. Parameter values were similar around the two cutting edges. Blade and shave plane angles, along with neutral guard and cap spans, were digitally measured from their corresponding photographs using a free scalable vector graphics program. For this razor, the edge of the cap acts as a pivot for the neutral and shallow shave planes. This convenient geometry was used with trigonometry, the measured neutral cap span, and measured plane angles to fairly estimate the blade width extension from the neutral shave plane to the cutting edge of the 21.96 mm wide blade used in the analysis. The neutral blade width was then estimated simply as 21.96 mm minus twice this blade width extension. Neutral parameters were then used to calculate blade exposure, guard span, and cap span for a blade having a nominal width of 21.96 mm. Finally, free-end and clamp distances between the three baseplate clamping supports were approximated using three width measurements and one angle measurement. This applied for a blade width of 21.96 mm, but using the neutral blade width, free-end and clamp distances were traced back to the neutral shave plane as reference values. 1957 Gillette Tech DE Safety Razor: Neutral Values* Associated with Zero Blade ExposureNeutral Blade Width21.52 mmNeutral Blade Angle24.95 degNeutral Handle Angle48.79 degNeutral Guard Span1.82 mmNeutral Cap Span1.27 mmNeutral Free-End Distance0.99 mmNeutral Clamp Distance, Maximum1.68 mm *See this ShaveWiki page for definitions of safety razor parameters 1957 Gillette Tech DE Safety Razor: Parameter Values* Associated with Nominal Blade Width of 21.96 mmSteep Blade Angle28.17 deg (w/ 45.56 deg Handle Angle)Neutral Blade Angle24.95 deg (w/ 48.79 deg Handle Angle)Shallow Blade Angle21.36 deg (w/ 52.38 deg Handle Angle)Blade Exposure0.09 mmGuard Span1.62 mmCap Span1.47 mmBlade Gap0.59 mmFree-End Distance1.21 mmClamp Distance, Maximum1.90 mm*See this ShaveWiki page for definitions of safety razor parameters Blade Alignment Is Very Good Symmetrically loading a DE razor blade in the Gillette Tech is very easy because the razor automatically does the job due to the small tolerance between the razor cap's bar width and a blade's cutout width. Based on my measurements of many blades and of my 1957 Gillette Tech, the bar provides a maximum of only about 0.12 mm of blade play for the average blade. Theoretically, one could force the blade to translate or rotate as far as possible within this constraint, which might be noticed by eye, but under normal circumstances, this razor naturally loads the blade very well on both sides of the razor. There is some noticeable lengthwise wiggle room (around 0.38 mm) because of (a) the gap between the cap's center pin and the average blade's center hole and (b) the gap between the cap's corner pins and the average blade. The cap's bar length is small enough to not affect the lengthwise blade play. Regardless, the small lengthwise wiggle room is inconsequential. Blade Tab Overhang Is Not Good The average blade hangs past each side of the Gillette Tech's head by about 0.98 mm, based on my measurements and calculations. Because of the blade tab overhang, loading and unloading the razor is neither comfortable nor safe with bare hands. A towel or something else should be used for protection around the razor head when loading or unloading it with a blade. Lighter and Smaller Than I Prefer At a little over two ounces in weight, the Gillette Tech is certainly not heavy. I like how the head is slim and maneuverable. However, the razor is lighter and smaller than I'd like. The handle, in particular, is thinner than preferred. Knurling Does Not Eliminate Slip The close-up photograph below shows the shallow knurling of the Gillette Tech in more detail. The knurling on the handle seems to help prevent slipping, but the handle does not eliminate it because the knurling is not deep or strong. The razor does not feel secure in the hand. Blade Rigidity Is Very Good Blade rigidity is the resistance to blade cutting edge deflection (URL). Compared to the four other razors that I've measured, the Gillette Tech has much better blade rigidity. The Tech's blade rigidity is very good because of the three baseplate clamping supports and the relatively small free-end and clamp distances of 1.21 mm and 1.90 mm, respectively, between the clamping supports. Blade rigidity is actually greatest along the baseplate clamping supports, where the clamp distance reduces to approximately the free-end distance, and between the clamping supports, blade rigidity is better than what one might think when only considering the free-end and clamp distances. More blade rigidity generally causes less aggressiveness and more efficiency. Some traditional shavers strongly believe in using razors with great blade rigidity. While the blade rigidity of the Gillette Tech is advantageous, other factors dominate its performance for my hair and skin, as discussed below. Could Not Modify Gillette Tech to Work for Me This might sound odd, but I only shaved once with the Gillette Tech in its natural state. That's all that it took to know that the razor was too aggressive for me. That shave occurred on June 8, 2018, and it involved an Astra Superior Platinum blade and a good lather. Dialing in the angle was not hard. The problem was the considerable drag from the cutting of hair on my face and neck. I actually expected this given the guard span, positive blade exposure, blade sharpness, and how my face has responded to similar setups in the past. With the grain (WTG) didn't really do anything, as usual, so I switched back to across the grain (XTG) and got some cutting, but as usual, against the grain (ATG) was the key and did most of the cutting. The shave was basically my usual XTG-ATG-ATG. ATG above the lip was awful, very rough with much drag and many weepers. The final closeness of the shave was similar to or better than my usual with a modified Bevel (URL), but the irritation and weepers above the lip were bad and there was some irritation in other places. The next day, June 9, 2018, I used the same Astra Superior Platinum blade, but with three reverse shims (URL) added on top of the blade to make blade exposure fairly neutral, as verified with a small flat acrylic piece. There was still drag, but at least the drag was much less than before. The resulting closeness was similar, or possibly slightly not as close, as what I'd normally get with my modified Bevel, and I only had one weeper that needed cleanup after the shave. Due to the drag, though, there was irritation after the shave. Finally, on the third day, June 10, 2018, I used a fresh Kai blade with four reverse shims to make blade exposure fairly neutral. The Kai blade is my favorite blade because of its sharpness and smoothness, so I expected a closer shave, which is indeed what happened. The final closeness had improved, but I got hacked up and there was a lot of irritation, even by the end of the second pass. The drag had probably improved, but it was still present and definitely greater than with my modified Bevel. The next day, I took that same Kai blade, placed it in my modified Bevel, and got back to normal. Even if modified to work at its best for me, the Gillette Tech would be rougher and/or less efficient than my modified Bevel. Reverse shims can only get me so far with the Gillette Tech. A heavier handle would probably help, but I already have that with the Bevel that also provides a smaller guard span for a smoother shave. Modified Bevel Is Still My Daily Driver It's possible that my second-quarter 1957 model is not representative of Gillette Techs in general, but the model is presumed as representative unless there surfaces convincing quantitative or qualitative evidence to the contrary. The Gillette Tech might feel "mild" to most users, possibly due in part to its substantial blade rigidity, but the razor feels "aggressive" to me because of its blade exposure and guard span. The razor burn or irritation that I got was something that I haven't felt in a long time. I was able to drop the blade exposure down to zero with a few reverse shims, but the guard span was still larger than desired, resulting in too much drag and irritation. It seems to me that the larger guard span, and possibly even the cross-sectional shape of the guard, allows too much skin to bunch up in front of the blade cutting edge. In any event, there was nothing that I could do to make the Gillette Tech work for me, so I put it away and got back to using my modified Bevel with a neutral blade exposure and a smaller guard span (URL). What's Next? The Fatip Piccolo (newer version, Mk 2) is on deck, courtesy of @Raven Koenes, who graciously offered me his spare. A lot of guys here love the Piccolo, and I admit that their enthusiasm got me curious about how the razor would work for me. No matter what happens, the razor will be photographed and measured in detail.