n.b. to someone considering buying this... i know i sound overly preoccupied with edge angle consistency, and you can probably ignore that. i think you generally get a pretty consistent, even looking bevel.
this was my first time using a guided system, and i like it a lot.
aside from SharpWorx Pro (SWP), i am also somewhat familiar with TSPROF because i had considered getting one in the past. it seems like one of the leading products in this space, and it has a lot of design refinements. beyond that, i have only very limited familiarity with a few other systems.
the SWP is very attractive to me because of the static abrasive concept. i already have stones that i like, and accepting bench stones gives you essentially endless abrasive options. i think it could be less attractive to someone who hasn't already invested in stones though because bench sized stones can be more expensive than the little things used on TSPROF-like systems.
imo, it is desirable for the dynamic part to be as light as possible as that gives you better control over movement and pressure. making it lighter also mitigates tool crash consequences. dynamic abrasive can be pretty light. dynamic knife is heavier. so anything that can be done to reduce the weight of the clamp(s) in SWP is probably good.
on to the clamps...
i know you're going to thumbscrews for the angle adjuster. one thing that bugged me was that two different sizes of hex driver were needed, lol. another thing... on the fasteners that lock the angle adjuster, the washers are not captive. if you need washers for the thumbscrews, maybe you could add a some kind of retaining washer to retain the main washer. maybe like thin plastic kind with an overall diameter smaller than the slot diameter.
the magnetic clamp is pretty cool, and i have not seen this concept in other products. it gives you pretty low achievable angle. you could even use it for thinning, but i'm not sure if you would actually want to. as i understand it, you frequently change the angle and pressure point in thinning to remove metal where you want. i'm not an experienced thinner, so maybe someone else could share their thoughts about that.
the blade and spine of a knife might not be parallel. i first thought to set up the adjustable spine stop at an angle to make the blade edge parallel to the clamp edge, but i realized that's a fail when you go to flip the knife over in the clamp. it would be sweet if the clamp itself were flippable, but alas.
it's interesting how the swarf builds up on the blade because of the magnet.
i managed to use this petty in it just fine:
but i think you can't use a knife much shorter in height. the magnet needs at least so much purchase for good clamping.
the magnetic clamp is not flippable, so you have to remove the knife every flip. that was kind of annoying, especially because i like to flip regularly on the final, low pressure, edge leading strokes (stone stropping).
i know you're planning on increasing the magnetic clamping pressure by using stronger magnets and reducing the distance to them. i think that's good because i had to be careful about how i held it to ensure angle consistency. i tried to hold it with at least one hand like this:
thumb on the clamp, index below the blade. basically, i was manually adding extra clamp force. increasing the clamp pressure will help with that, but i hope it doesn't make flipping too much more annoying.
have you considered a design that utilizes magnetic field shunting (like
magswitch magsquare, see
demo) "switch off"? it adds cost, complexity, bulk, and mass (which i know i just said is bad for the dynamic side), but it could be pretty cool.
on to the normal clamp. the current one is ok, but i'm glad you're upgrading it. i won't go into too much detail since it's not making it to the next design iteration anyway. i managed to sharpen a sypderco chaparral, but i think you can't go much smaller with it:
i do ok, but i'm honestly not that good of a sharpener. i have trouble with angle consistency, curved blade sections, tips, etc. i do manage, and i get my kitchen knives sharp enough freehand. however,
i have a lot of trouble with pocket knives, and i find few opportunities to practice. this blade is basically entirely curved, and it's small, so the muscle memory from kitchen knife sharpening doesn't translate well to it.
with the SWP, i reset the spyderco chap bevel to something nice, even, and fairly crisp looking. it's the sharpest i've ever managed to get the thing. freehand, i couldn't get it as sharp as it came from the factory, so i'm very happy.
i saw your rapid prototyping in your
new vid. the clamp design looks a lot like TSPROF. not sure if you were inspired by theirs, but if you haven't looked at it, you should. they might have the best clamp design, so might as well rip it off or even see if you can improve upon it.
the 'level joint' on the vertical rod adds a horizontal offset (illustrated in my prev pic... green lines). have you ever considered canceling that offset by moving the vertical rod over ~1cm left or right to put the horizontal rod in line with the stone holder's centerline (red line)? i.e. make the part of the base that holds the vertical rod a scalene triangle instead of isoceles. i don't think it would add cost or bulk to the design. you may notice that i have the stone mounted offset. i couldn't help myself, lol. this ties into my preoccupation with angle consistency across the stroke. also, with some knives (like this pocket knife), you can't move the blade heel past the edge of the stone. the ricasso or thumb guard or whatever gets in the way.
after several hours of use, i noticed that the level joint got squeaky and was no longer smooth. taking it apart and putting it back together fixed the issue, and i'm not sure what went wrong, but
would it be good some kind of washers at the fastener head and at the locknut? i was surprised to see that missing. assembly mistake, or is it really not needed?
i am also noticing a distinct absence of low-µ polymer in this project. maybe this could be a good spot for ptfe or delrin, lol. i endorse any project that uses delrin. for example, on the right side in the above pics: level block, delrin washer, thin metal washer (to distribute the clamping load), bolt head. or two more thrust bearings + washers, lol.
