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I am confused by "concave edges". If you mean cambering edges on plane irons (grinding back the outer edges to eliminate "plane tracks"), the SE77 is the ideal choice, as the amount of camber can be carefully controlled. Before we had the SE-77, we used the SE76 and leaned on the corners. This produced cambered edges which, if not exact, were usually close enough.

The OP really is talking about a concave edge as in ground with a wheel instead of a plate (slightly convex edge) or a belt (more pronounced convexity depending on pressure and belt slack) :

What i don't know is how well or bad planar blades is with a concave bevel? I'm currently using my works sharp belt sander for dito, which gives me a convex edge and that works great.

In theory, convex blades have a tendency to skim/pull out, concave blades will dig in. I don't think you'll notice much of a difference in practice because the convexity will not be that pronounced over the thickness of the blade.

I'm not sure sharpening scissors with the SVD-110 would be easy, especially those with a narrow blade.

The SVX is really fine for scissors, I've never tried to use it instead of the SVD, as I'd worry about damaging the surface with a teflon (or similar) coating. You might get away with clamping a protective plate onto the SVX base jig though, in some cases.

Honestly, to me it sounds like you just need practice.  But I tried to add a couple of tips that may help.

my tip/round part gets more angle. im shopening at 12 and i think is more like 15 or more.

i thought the laser would help when lifter to keep all of the blade edge cutting from the same spot on the stone, to keep the same angle.
Am i misunderstanding this part?

There are many discussions on this subject in the forum including this one.

TLDR : if you try to maintain a constant angle at the tip on most knives, your bevel height will vary. If you want to maintain a constant bevel height your angle will vary.

This is due to the intrinsic geometry of the blade. For instance if the blade curves upward at the tip, it may get thicker because the angle at the end of the blade spine does not correct enough for this. So if you maintain a constant angle, your bevel will get wider.

If you take a close look at videos where a nice bevel is being ground all along the length of the knife, you will notice that the sharpener (Wolfgang included) uses a combination of lifting and pivoting (sometimes away from you, but sometimes towards you).
This is where sharpening knives on a Tormek becomes more than just using a jig in a predetermined fashion. You have to work out what combination of clamping position & clamping angle wrt to the spine, lifting action and pivoting action will work best for the geometry of the particular knife you're sharpening. 

If, like me, you don't sharpen enough knives that you'll be able to adjust on the fly, the "sharpie trick" will help you a lot in finding that combination : blacken the edge, take one stroke just lifting the handle. Look at the edge. If you ground the apex portion but still have sharpie along the top of the edge, add a bit of "pivoting away" action at the end. If you ground the shoulders but not the apex, pivot towards you. Rinse, repeat. When you want to start pivoting will depend on the precise curvature of the blade, so you might want to take a close look at sharpie marks not just in the tip area.

This might only compound the issue you mention in point 2. of your original post. But you will have to build muscle memory and develop habits to get more consistent, there is little helping it.

Hope this helps.

I would point out one possible constraint in your design. The out of round shape of the bore is a patented design held by Tormek called Torlock. I don't believe making a platform for your personal use would be problematic; however, anyone wanting to manufacture them for sale would face breach of patent legal action.

Ken, thanks for pointing this out. I did a bit of preliminary research on patents advertised by Tormek on their website, and could only find something related to this in the patent for the vertical sleeves of the USB. I didn't see anything related to the Torlock mechanism.
That being said, I know of a few other designs where a round shaft is held in, say, one corner of a square hole by a screw, including on a centuries-old loom in a french museum. I'll be damned if nobody thought of making it a triangle (which is essentially what Torlock is) by the time Tormek applied for their patent. The research report for this patent would be interesting in that regard.
Nobody would dare manufacture this on a large scale anyway : plastic filaments will not be very robust in the long run, and a metal version would be very expensive to make.

Guess I don't see the need for a "sliding platform"... the Platform should accommodate just about any size knife without the need for this?   

The idea was to be able to choose the working position (platorm angle) for any grinding/honing wheel diameter, without being constrained by a unique angle/USB combination. I could make one or a few fixed-length variants though, if there are "projection" distances you feel would work well. Those would be cheaper, require one less ruthex insert, and be less "fiddly".

Please share the STL files.

Rich, I'll gladly send you a link to the STL (and/or f3d) files in a PM. Don't you want to wait for the inevitable corrections, though ?

Ken, I understand your point.

But again, I think this is one of the points where the fact still shows, that knife sharpening is what I call an afterthought for Tormek.

Maybe they should think of a "Premium Knife Sharpening Edition", with the knife jigs, new angle setter instead of the AngleMaster, MB-102 and US-430 instead of US-10x.

The standard US-103 support can handle knives with blades up to 200mm (8 inches).

Ken

With very little wiggle room to choose where to clamp the knife, though.

Hello,

Having no metal machining skills nor equipment and few parts to tinker with, I thought I'd give a try at a simple "Platform Jig" that I could 3D-print.

There is nothing fancy or innovative with a simple adjustable plate to rest a blade against, it just feels like it's missing from the Tormek jig lineup.

The objective is to be able to accomodate as wide a range of angles as possible, not limited to short blades but well suited to those as the SVM-00 is kinda fidgety.

I'll use PLA filament for the prototypes and ASA for the real thing, trying to avoid supports except snug ones for the two holes for ruthex inserts (thumbscrews) where geometry matters little.

A quick note on a design choise (which I am not sure is wise): the (grey) sliding platform is more or less self-locking inside the (blue) support. One has to flex it a bit by pressing down in the middle so it slides easily, then release it so it locks back in place, and the (red) back thumbscrew is just here to secure it in place and prevent bending. I might have to play with tolerances and/or add a bit of teflon or the like on the outer surfaces in contact with the support so it slides more smoothly but still locks without significant radial play..

[edit]And a second note : I might not be able to dispense with having to add a metal plate on top on the side of the slide that is close to the wheel, if I have to thin the tip and keep everything rigid.[/edit]

Please feel free to give any feedback that I could incorporate before the first actual prints.

Cheers,

Nick.

If you ever intend to sharpen knives, at least anything beyond short knives, I think a US-430 is well worth the price difference.

I second what John wrote. That being said, I never use the SP-650 on the SJ, as it gets quickly full of blue sludge, and the SJ is so soft that I would be afraid it got way too easily out of square if I don't hold the SP-650 perfectly square to the stone. It could also go out-of-round easily as the SP is very aggressive for the SJ.

Rather, I keep it clean with a rust eraser, and true it from time to time using the diamond tool (and making sure I always go into the stone with the diamond tip, not out of it). The surface might be slightly rough right after truing, but essentially because of artefacts left by the truing tool. The surface will get back to smooth as silk after a few seconds of sharpening.

Another useful tip is the grading procedure demonstrated by Wootz, using a very fine diamond plate and very little pressure (to avoid getting the stone out-of-round).

If 6 to 8 minutes are only 10% of the time needed on other devices, then either those devices are very ill-suited to knife-sharpening, or maybe you're only using the #6000 grit belt/stone 

Hi !

I think your best bet for these would be found in the 3D-printing community. For instance :

This trough drip collector or this one here. I use a similar one for my T-8 almost all of the time.  Of course that only works if you have access to a printer.

Although to be honest, water spillage has been tremendously reduced since I first began to use the Tormek. Having the trough set so the water goes just over the wheel but not too much, lifting just as required, all those eventually result in very little water spillage. My drip tray (or the T-8 collector on the trough side) now only get a few drops for each knife.

I've not been on this forum for a long time, but I'm amazed at how good an example it is of a company fostering a community that results in an optimized use of its product as well as continuous improvement.

Some members such as Dutchman or the late Wootz, or more recently Perra, have been instrumental in paving the way for breakthroughs in sharpening efficiency and/or precision. I hope they get credited one way or another, like through patents for the MB-102 or the KS-123.

Kudos also to Tormek for listening and overcoming the classical initial corporate resistance to criticism, and eventually incorporating those ideas into further improvements of their tools. The blending of the MB-100 and FVB into the cost-efficient MB-102 is a brilliant example of how to use community feedback to keep their product line top-notch.

Some of the members are unsure if tomorrow's class will be part of Tormek's youtube channel. Some reassurance from you would be most appreciated.

The video is titled as "Part 24". The first 23 parts being part of the Tormek Youtube Channel, I think worried forum members can relax. Clicking on the video itself will also allay their fears as they realize they land on a familiar channel.

To me there is a world between 150 BESS and 100 BESS, and another one (maybe two) between 100 BESS and 50 BESS. I have never gotten to 50 BESS, but the standard SG/PA-70-on-leather setup gives me consistently 90-110 BESS with 15 dps, and 85-100 BESS with 12.5 dps.

150 BESS happens in a few situations that I can think of :
- Knives made out of junk (soft) steel. They can't be sharpened at an acute angle and an obtuse angle yields poor results anyway.
- Partially honed knives. There is a burr or some plastified metal left, so they have to be honed some more.
- Medium quality steel finished with chromium oxide or diamond spray on felt wheel. I could never figure for the life of me why it would degrade BESS readings, but it does, probably because of poor technique. The readings get back to 100ish if I hone them again on the leather wheel. This phenomenon doesn't happen on 63+ HRC steel.

So I wouldn't loose courage if I were you, I would try to hone a bit more than you usually do, and remember Vadim's results that low initial BESS is not a significant factor in edge retention. Steel quality and edge angle are, though. I also find that SG edges tend to retain their cutting ability longer than SJ edges.

Right again, I forgot about the split.

Out of curiosity, have you checked with Tormek that they won't consider it a patent infringement on their SVM-45 and/.or KJ-45 ?

And if not, would it be less expensive overall to just go all the way and may an entire jig from scratch, free from compatibility constraints with the KJ ?