Thursday, April 28, 2016

Rasps Part 1

So I bought some rasps, which are hand tools a lot like files but instead of rough grooves they have an array of teeth that scrape wood away. I consulted the fine folks at The Dusty Life (who were crazy enough to put me on their podcast) about what to buy. Basically, I asked "If life's too short to buy crappy tools, is it worth getting great rasps?" I ended up getting great rasps.

A discussion on rasps, which is admittedly kind of a woodworking geek subject, follows after the jump. I broke up this post into two parts because it kind of got long. So, the first part is about rasps in general. The second will be more about the rasps that I bought and examples of them in action.

So the consensus top quality brand of rasps are made by Auriou Toolworks at Forge de Saint Juery. I ended up buying two of them. Before I tell you about them, first I'll tell you about rasps, then I'll tell you why I *didn't* buy something else... and if you've stuck with me through all that (impressive), then I'll tell you about the Auriou rasps.

First off, from 0:04 - 1:00 in this video gives a real quick overview of what a rasp is used for and shows someone using one:

The definition of a rasp, according to Wikipedia, is "In woodworking, rasps are used for rapidly removing wood from curved surfaces. They remove less wood than a drawknife, so they are easier to control. Even though rasps leave very coarse finishes, the cut-away areas can be easily smoothed with finer tools, such as files." They are used predominately to shape concave and convex surfaces.

Rasps come in a range of roughness (e.g. rough, fine, etc.). So, like with sandpaper, it helps to have a couple so you can rough shape and then smooth out with a finer tool.

Rasps are either machine-made, or hand-stitched (hand-made). A helpful person on the twitter heard the podcast and chimed in with his advice:

So with that in mind, I also considered what I learned from the podcast itself. Kyle Toth, who knows what he's doing, suggested on the The Dusty Life Podcast that I look at Nicholson rasps, which are what he uses. So, since he knows much more about this sort of thing than I do, I did. Turns out that Nicholson moved production of its rasps to Brazil a few years ago. Then I see things like: "It should not be this hard - We Discontinue Nicholson Patternmaker's Rasps Because of Quality Issues." That doesn't exactly inspire confidence. I checked with Kyle, and he thinks his Nicholson rasps predated the move to Brazil. A little more digging and the internets seem to agree, the quality of the Nicholson rasp has declined since the move.

I checked with my uncle who suggested looking at ebay or craigslist to try to snag a few old Nicholsons at a cheap price used. If you want to buy rasps that have been stored together in a big cardboard box where they can clank against each other dulling the teeth, you can totally have your pick of cheap options that way. Buying a tool that was once good, but has since been beat to hell and back by owners that neglected to take care of it doesn't really fit my definition of "not crappy."

Okay, so that means I was looking at new tools. That gave me, essentially, a few options.

1. Machine-made rasps.
2. Mid-range (i.e. Nicholson) hand-made rasps. [already ruled out]
3. Top-quality hand-made rasps.

So lets look at what the differences between a machine-made and hand-made rasps more closely, shall we? We shall.

Machine-made rasps can be had for a reasonable price. For example the Narex 250 mm 10" Half Round Cabinetmaker Wood Coarse Cut Rasp 872523. It retails on Amazon at the time I typed this for $24.99, which is a reasonable price, especially if you want to outfit yourself with a set of rasps like rough, fine, finish. Here's a picture of the Narex 10" Half Round Cabinetmaker Wood Rough Cut Rasp:

Note the uniformity of the teeth
If you can blow that picture up you'll see that the tooth pattern is repeated over and over again along the length of the rasp. I'm going to quote Fine Woodworking (the JAMA of woodworking) here because, again, these guys are smarter than me. "[Your rasps] should all be tapered half-rounds and have random-cut teeth, which are almost always hand-cut. Most machine-cut tools have perfectly spaced teeth, which contribute to 'railroading' (rows of grooves on the work surface)..." (source: FWW, Issue #208 p. 42).

This is where the difference between the $25 machine made Narex and the pricier hand-stitched rasps comes in. Each tooth on a hand-made Auriou is, obviously, set by hand. That means the tooth pattern is random, or maybe more precisely, inherently imperfect, and that imperfection means the material you work on shows fewer signs of being worked. In the words of Fine Woodworking, there's less "railroading."

Example of hand-stitched teeth
Here's a video that Auriou Toolworks put out showing their rasps being made (pay particular attention at about the 3 minute mark):

So, once I considered all of the advice, I ended up going with two Auriou rasps. Tune in for Part 2, in which I talk about them! (exciting, no?)

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