UL folding saw
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I got one of Jan’s for the 130. Here’s my Pocket Boy 130 vs his saw.
so far, so good :)
A photo of the short handle (silkyboy 130) next to the original one (silkyboy 170). On the last series, I also made the teeth cover in color.
I got my handle from Jan last week and brought my “PocketJan 130” out for a 2-nighter this past weekend. Very happy with it, the handle feels very sturdy! Compared to the original handle it’s way more packable thanks to its weight, flatness and that the blade’s edges are less exposed.
We used the saw to cut up some birch and old pine with nice heartwood for fires. Hard work but not to any fault of the handle :) It felt comfortable enough with thin gloves on. The locking mechanism is sturdy and firmer than the original, but easy to handle
Unfortunately my blade tip has broken off (old accident) so the blade doesn’t lock into place when closed. There is enough friction in the bolt that holds it together though so it’s not an issue
This winter I redesigned the lock of my 3D-printed saw handle, making it stronger and more reliable.
In the first version, the latch of the lock is pressed into a groove in the blade by a spring (analogously to the original Silky handle). However, the geometry of the groove is such that a force pressing on the blade pushes the latch out of the groove – this is described in more detail in this post. I know about two failures of the early prototypes (fixable by replacing the spring or the whole lock – spares are provided), then I made the spring stronger and it seems it solved the issue. Even with this fix, I was not 100% happy with the lock – it also required removing a material from the spine of the handle, just in a place where it bears the highest load.
The new lock works differently and solves both these issues. Now the blade is locked with a pin that moves sideways through the handle. It can’t be pushed up by the sloping groove in the blade, and the neck of the handle can keep it’s full thickness. The lock is released by pushing a tab on the spring that holds the pin in place.
The catch is in making the pin – it took me a while to find a solution that wouldn’t be bulky. It requires cutting a precise, deep groove into a stainless steel rod which is tricky. It would be easy with a lathe, but I don’t have one.
Here’s how it looks:
compared to the first version:
This picture shows nicely how the new lock allows keeping full thickness of the handle, making it stronger just where it’s needed the most:
And the complete saw (130 mm version):
I also updated the materials used. Previously, I usually printed the handle out of carbon-fiber filled polymer which is very strong and rigid, but because of it’s rigidity, it’s also somewhat brittle when loaded to its limits. It was OK and I’m not aware of any failure due to this, but I’d prefer a more resilient material. Recently, a new printable plastics called PCTG appeared which has exactly the properties I looked for – it’s stiff enough for this use, but also very tough. It bends rather than snaps when loaded to the max. Now both the black body and color parts are made of PCTG.
A small update of the saw handle project. The new lock described a couple of posts above works great, no issues since then. I also switched to a new color scheme using translucent filament – it shows more of the 3D-printed structure, and I like it more than just a plain block of opaque plastic. Its still the PCTG polymer which offers goof balance of stiffness and toughness. Here are pictures of both sizes (for the 170 and 130mm Silky Pocketboy blades) next to each other:
In the larger version, I added a little more internal reinforcements. The handles now weight:
170 mm blade version: 42 g / 1.48 oz
130 mm blade version: 36 g / 1.25 ozand with a 10 TPI blade mounted:
170 mm blade version: 75 g / 2.65 oz
130 mm blade version: 68 g 2.40I also experimented with a larger blade from the Gomboy saw, but the locking notches on the blade are different, and much narrower, so it doesn’t work with the locking pin. I will try other options, but it may not work without modifying the blade itself.
Two years later and I just realized BrianH’s post desperately needed to be turned into a meme.
A shout-out of thanks to Jan for a brilliant piece of kit! I ordered and just received two saw bodies from him for both the 130 and 170 Silky Pocketboy Blades (both Medium Teeth). The 130 will be my regular backpacking saw, and will replace the tired and true Opinel I’ve carried for quite a few years. The Silkyboy 130 has larger, more aggressive teeth, and will shave 1.52 oz’s as well as being more compact. The 170 weigh’s 1/2oz more (2.86 oz’s) and will likely be more of a cold weather saw.
When it comes to replacing the blades in the field, I have a modification that allows it without tools. It’s a result of a discussion with someone who suggested using a knurled nut for exactly the same purpose.
I modified the plastic disc that holds the blade so it’s now two parts. One serves as a washer and does not rotate (so the screw does not get loose when the blade is opened and closed), similar to the standard part but thinner. The second part has a tight socket for a hex-head screw and ribs that allow tightening it with bare fingers. Here it is, mounted on the saw as well as the parts themselves:
To test it, I have it on my saw for almost a year, and it works well. However, I still prefer the standard phillips screw and metal washer which are more robust and lower profile.
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