The problem was that my eyes are now full of steel dust and I can't see if the blades were scratched and if the scratches were on the mounting screws or which skates I even sharpened.

I hope you use protective goggles when sharpening with the powered sharpening machine, or working in a machine shop. Many people do. I admit I don't when using Pro-Filer but I've never had that produce dust that got in the air. I have used goggles while using a drill or saw.

tstop4me - but my concern is only on scratches that might conceivably add extra drag while skating.

Thoughts, ideas for improvement?

Yes, I have a lot of thoughts. Please implement this ingenious plan of yours and come back afterwards to tell us how your wooden tool works and if you got within the 0.01 tolerance you mentioned earlier.

In the meantime, I'm going to the eye doctor. I did grind the blades with the tool I printed. Enthusiastic about the given tips, I printed a jig that holds the printed sharpener in place, with the groove facing downwards. I lie on the floor with a skate in my hand and move skate against the pro-filer above me. It was a bit difficult. The problem was that my eyes are now full of steel dust and I can't see if the blades were scratched and if the scratches were on the mounting screws or which skates I even sharpened.

When my eyes are recovered, I have planned to print Profiler type of sharpener which has same profile as the blade what I am sharpening. Means it has same lenght as the blade I am sharpening. I can tune the profiler so that I can do 3 or 4 sweet spots and many other cool things. Unfortunately I cannot describe how it works, but its going to be revolutionary.

Revised wooden version:

1. Take a 2x2 board (exact size not important), cut it to the desired tool length.
2. Use a bench circular saw, jig saw, or band saw, that has a fence accurately parallel to the blade. Set blade to be perpendicular to table. (A handheld jig saw with a fence or strip cutting attachment might work, would be less accurate.) Recut the sides and ends of the board to be perpendicular to each other.
3. Mark the center of the board on one of the ends. (The center is at the intersection of the two diagonals.)
4. Use a compass to draw a circle about that center with the desired ROH radius on that end.
5. Find the middle of one of the sides of the end, and draw a line with a pencil from it to the center, and to the other side.
6. Cut a gap centered on that line, as accurately as you can, from one side to the circle or a bit further. Use the fence (or strip cutting attachment) to keep cut straight. The blade should be slightly wider than the skating blade - which might eliminate the possibility of using a jig saw or band saw, if it isn't wide enough.

The stripping I was referring to was of the heads, not the threads.

The bolts you show have circular heads, which you can't put a wrench on to turn them. So they probably have one of the following:

1. Small hex key holes, that you fit small hex keys in. These strip very easily with ordinary hand strength.

At least that is my experience with the soft aluminum bolts that were used to hold the runners on in the old Matrix 1 blades. It helps if you find high quality hex keys that exactly fit the holes - e.g., if you initially need to use a hammer to lightly tap the key in. (Don't use the key for anything else than this!) Then, after a few uses, the holes wear a bit bigger, and you can no longer insert the keys without much play - and it is that play that causes the holes to strip. Then you find various cheap hex key sets, some of which will happen to have slightly too large keys, and you use them. Finally, when the holes have too much play to be used without stripping the bolts (and if you let it go too long, you need special tools to remove them), you need to replace the bolts.

2. Phillips heads. Even if you use exactly the right size Phillips head screwdriver (hint: good quality screwdrivers work a lot better here.), and press down hard as you turn, Phillips heads slip a little against the screwdriver bit, and eventually slip, and very soon strip the head. I know engineers often claim Phillips heads are great, because you can insert the screwdriver in a few tenths of a second faster than anything else, but to me, they will always be a sign of shoddy workmanship.

3. Slotted heads. Much better than Phillips, at least if you can find one of exactly the right size, and once again press down hard as you turn, but they eventually strip too.

4. Torx heads. Likewise. Though these strip slower than the 3 above, but they aren't all that common. So it isn't likely that the roller bolts use them. And like hex keys, they are too small, and eventually strip too.

5. Tamper resistant heads, that require a weird shape screwdriver tip. These never seem to be well designed against slippage, and it is hard to replace the screwdriver or screwdriver tip. Yuck.

I think a stainless steel hex headed bolt really is best, provided there is space to use a socket wrench. A square headed bolt works about as well - but it is harder to find socket wrenches that fit them.

That said, you have to use what is available.

Edea does make machine threaded screw sets that attach from the inside.  They make these for quad wheeled skaters.

Edit:  I know I saw those online once at a quad skate shop in Florida, but I can't find them now.  However quad shops do offer special flat head machine screws that use a washer and nut on the outside.  This would work but look a bit strange.

Those hurricane nuts - I think also called T nuts -- would work fine.  Just using them in the heels would be a challenge.

Why couldn't you use any flat-top head bolt of the right length, plus an appropriate nut?

If I remember right, a skater who needed to change her blades frequently (I think she had been a show skater, and frequently had to skate on "artificial" plastic ice, which is more abrasive) once told me that she had used bolts and nuts to secure blades. But she used thin nuts - I thought on the inside not outside of the boot.

And years ago (before Edea was popular) a person who ran a skate shop told me roller skates often attached the chassis (is that the right word??) that holds the wheels using bolts and nuts - again using thin nuts.

But I haven't done it, or seen it done. Maybe they really did put the bolt on the inside?

Regardless, if, like most blades, the holes are countersunk, I assume the bolt or nut on the outside should be countersunk too, so it fits right and locks the blade in place. And for both nuts and bolts, I presume stainless steel is much less likely to rust than galvanized steel.

There are a lot of Youtube videos about people who had trouble removing roller or inline mounting bolts, because they stripped the head. As with any screw or nut, you can strip the head if you do tighten or loosen it wrong, e.g., with a tool that doesn't quite fit, which makes them much harder to remove - though there are ways to do it - most of which involve buying extra tools. In addition, hex and square head bolts are less likely to strip then hex key driven bolts. That's especially important if you are going to do this so often.

P.S. There are many threads on this site about sharpening your own blades. If you have the right tools, they fit your blades, and you have some degree of mechanical intuition, you can learn how. Do I remember that you participated in some of those threads?