When it comes to talking about Stanley hand planes, I guess one can never say it enough…. Stanley was obsessive about filling every niche, real or perceived, in the market. Through out the thread, I’ve written those words many times, and will present another example of that in this post. So let’s get into it.
A fairly common woodworking joint is a dado. To the best of my knowledge, it is a slot that runs perpendicular to, or across the grain of a work piece. A groove is a slot that runs parallel to, or with the grain. Both joints are tried and true classic woodworking staples. Of course, Stanley was well aware of that, and as a result, offered planes to cut both. Now I certainly don’t want to insult anyone’s woodworking intelligence, but I think the two terms (dado and groove) get used interchangeably, and I’m guilty of using both terms incorrectly on occasion. For purposes of this discussion, it’s important to get the terms right as the design of the plane depicted below necessitates that understanding.
Between 1902 and 1952, Stanley manufactured dado planes in sizes that ranged between 1/4” wide and 1” wide, separated by 1/8th increments. The planes were numbered as the “39” series. (Stanley also produced a 13/16” wide version by machining down a 7/8” plane. It’s very rare and a topic for another day.) Unlike some of Stanley’s plow planes (like the #50 for instance) and combination planes (like the #45, #46, #47 or #55) that had different width cutters, the Stanley dado planes were size specific. By that I mean that each plane was designed to cut one width and one width only. Consequently, a craftsperson would need to acquire eight separate planes (1/4”, 3/8”, 1/2”, 5/8”, 3/4”, 13/16”, 7/8 and 1”) to have the full range of sizes. For a person making a living with them, that could be a lot of cast iron to be hauling around. Perhaps a combination plane would be more economical and portable. One might notice that the #39 series of dado planes started at 1/4”. Well, Stanley being Stanley, it seemed only logical that eventually someone in the marketing department realized there was no 1/8” wide dado plane in the product line.
Stanley #239:
This is an interesting little plane with an unusual developmental history. The #239 was offered by Stanley between 1915 and 1943. It started out as a 1/8” wide “dado” plane. I’m making sure to call it a dado plane because it was designed to cut a slot across the grain. In order to do that without producing a lot of tear out, the #239, like Stanley’s larger dado planes, was outfitted with a spur that’s mounted vertically in the plane body, just forward of the cutter. The spur is meant to score the grain, thus reducing unsightly tear out as the cutting iron passes immediately behind it. That’s important. A true dado plane needs a spur on either side of the plane body, the same width as the cutting iron, in order to cut across the grain cleanly. The spur on the #239 then is 1/8” wide and filed into a V shape to reduce drag. When mounted in the body of the plane, the V is inverted and its points score the grain as the plane is pushed forward. It works well as long as the points don’t get dull. Now remember, a plane that cuts a “groove” with the grain doesn’t need a spur, it typically needs a fence. This is where the “unusual developmental history” occurs.
Between 1915 and about 1925, the #239 was manufactured without a fence. It was designed to cut a dado across the grain. Stay with me here….. At some point, right around 1919, Stanley introduced another plane, the #239 ½ “special” dado plane. It looked VERY similar to the #239 with a few differences. First, the #239 1/2 was manufactured without a milled recess in the plane body to accept the vertically mounted spur, and it was also equipped with a fence. That sounds like a plow plane to me! Why Stanley called it a dado plane is unknown. It seems that the #239 ½ was designed to cut a groove running with the grain of the work piece. (See how the two words, dado and groove, are used interchangeably and sometimes incorrectly?) Anyway, the #239 ½ co-existed with the #239 in the Stanley hand plane lineup until approximately 1923 when it (the #239 ½) was dropped. In 1925, the #239 was equipped with a fence. It still retained its spur too. Essentially, later versions of the #239 were a combination of the early #239 and the #239 ½. Shorty thereafter, around 1926 or so, Stanley “discovered” the need for three more sizes of the #239. So not only could one buy a 1/8” version, but also a 5/32” (offered between 1927 and 1941), a 3/16” (offered between 1926 and 1941), and a 1/4” (offered in 1926 – this one is extremely rare!)
The #239 depicted below is the most common of the sizes offered by Stanley, 1/8”. It was probably manufactured at some point between 1925 and 1935. There are some clues. First the most obvious….it has a fence, which was initially offered on the #239 in 1925. Prior to 1925, the #239 did not come with a fence. Take a look at the trademark on the cutting iron. That trademark was commonly found on cutting irons manufactured between 1923 and 1935. Finally, notice the label on the box. See how it says, “IMPROVED DADO PLANE”? Well, my guess is that the “improvement” to the plane was the addition of the fence assembly.
While I would never discourage anyone from adding a #239 to his/her collection, I will say that they’re somewhat rare; even the 1/8” version. The same goes for the #239 ½. If you find one or the other, make sure it has all of its parts. Tracking down a correct cutter, spur, little screws and washers, the fence assembly, etc. can be expensive if you can find the parts at all. There are also other things to think about. Know what you’re looking at! Do your homework! Know which versions of the #239 had a fence and which ones did not. If you see a #239 with empty threaded holes on its sides, those were meant to accommodate threaded rods for mounting the fence on the side of the plane. Don’t mistake it for an earlier (pre 1925) version of the plane. Earlier versions of the #239 did not have a fence, and consequently no threaded holes on the side of the plane’s body. Seeing threaded holes with nothing in them should always be a red flag. ALL #239 dado planes had a vertical recess milled in the main body to accommodate the spur. NONE of the #239 ½ planes had a spur and consequently no recess milled into the body. All #239 ½ planes had a fence. I hope you’re not completely confused. If so, check out the photos below, and maybe they’ll clarify a few things. Thanks for hanging in there on this one!
Jim C.
