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Where does the 10 degrees come from? Is he assuming the scissor blade is a 10-degree wedge?

I also prefer the marker method.

Not only does the angle differ on each of the blades, I have sharpened scissors where the angle changes along the length of the blade. In that case I just use the angle at the center of the blade. But I'm not sharpening any special-use scissors, just kitchen scissors and scissors for cutting paper or cloth.

My daughter-in-law is a hair dresser. She won't let me near her very expensive scissors and I don't blame her. I've seen videos of how those are sharpened and a Tormek is not up to that task.

My grandson has been watching me use my Tormek since he was a little kid. Now an adult, he can sharpen a knife by hand with great skill. He still comes over to use my Tormek on occasion.

If the self-tapping screws won't penetrate then you do have to drill pilot holes. It sounds like your drill bit is dull. Small drill bits dull easily. Buy a new one.

Does the honing wheel wobble in sync with the grindstone? If so, it's likely a bent main shaft.

I redressed the wheel and checked for tool rest bar perpendicular to wheel, all looks good,

Not sure what's perpendicular to what? After truing, the cylindrical surface of the grindstone will be parallel to the horizontal portion of the universal support rod (USB).

however, when I ground the first blade the top is now ground dramatically out of square.

It's absolutely essential that the horizonal portion of the USB be parallel to the axis of rotation of the grindstone. They could have been knocked out of parallel if the USB was bent or if the two vertical portions of the USB are not parallel to each other. Or both! Less likely, but still possible, the frame is bent so that the main shaft no longer points in the same direction it used to. Perhaps before you ever acquired the machine it had fallen on the floor!

After removing the rust, I sanded the Tormek with abrasive fleece and then rubbed it with acetone. So far, no new rust has formed. The painter wanted to blast it with glass beads before powder coating. So actually, I could have saved myself the trouble of removing the rust and paint.

Yup. I didn't realize you had a professional doing the powder coating. You'll have a machine that will last the lifetime of your your descendants. The bearings are simple affairs that are easily replaced. In fact, every part is replaceable.

Mine is a unique handmade piece. I built the power supply almost 35 years ago during my first year of vocational training. In the vocational school we etched, drilled, and soldered the circuit boards ourselves. We also sawed, drilled, and filed the housing. We even screen-printed the front panel.

Impressive. I'm jealous of both your machine and your training background. When I was a secondary student in the 1970's I got slotted into the college-bound track so I received no vocational training or education.

Interesting that a up until a few decades prior to that every physics major had to receive formal vocational training to become a machinist. Somewhere along the way our society had lost the value it used to place on learning how to use tools and work with our hands. I see that changing a bit now, with a greater emphasis on hands-on education in the trades to prepare students for a career working with their hands. It's a great alternative to racking up huge debts from receiving degrees and advanced degrees that too often never get formally used, just because that kind of education is more respected in our society. I believe it's better for your physical, financial, and especially mental well-being to have a career working with your hands as opposed to working behind a desk.

As one person put it, in academia and many other careers the only purpose your body serves is to get your head to the next meeting.

The rust removal with electrolysis worked very well.

I'm glad that worked well for you. My understanding is that once you do get it down to bare metal it will immediately start to form a light rust on the bare surfaces. Normally one would apply oil to prevent that, but of course you wouldn't want to do that to a surface you're going to paint. I don't know if you should just let it rust, rub with #0000 steel wool, and then immediately apply a primer designed to bond with the rust. Years ago this type of primer was touted by manufacturers as all the rage, but it seems that now I can't find it in the stores. Perhaps it's been incorporated into all good metal primers.

By the way, andicugino, can you tell me what you're using for a power supply? I see it in the photograph of you performing the electrolysis. I'm interested in a good quality battery charger. I'm afraid the tiny one I have is damaging the batteries I'm charging.
 

Andi, I just painted mine flat black because I had a rattle can of that again left over from some previous project, but whatever color you choose I recommend a semi-gloss or satin finish rather than flat. On the other hand, flat paint makes the telegraphing of ridges around the old rust spots less apparent. Depends I guess on whether you want to go for easier cleaning or better looks. 

Actually, I recently realized that it's not flat black, it's probably semi-gloss. That makes for easier clean up.

There is an assortment of jigs and accessories that come with the Tormek. The newer T7 and T8 machines use many of the same accessories or jigs, although the newer ones are a bit different. If you do some google searches you can find photographs, drawings, and videos of them. Go back in the shed and see if you can find them. In particular, there is a leather honing wheel that fits over the rubber drive wheel, and attaches with a threaded knob.

If you don't have the Universal Support Bar (USB) see if you can find the original in the shed.

All of these parts are still available, although they may be upgraded versions. They will all fit your machine. If the Tormek you found still runs, it may be worth it to you to buy some of these upgraded accessories. Especially the USB and the truing tool.

I don't have any experience with CBN, but you can use the the SG-250 to first establish the edge at the desired bevel angle. Then, use the fine side of the stone grader. Apply a lot of pressure for a long time. Then grind the edge, after which spend a lot of time on the honing wheel. I have looked at these surfaces with a dissecting microscope and fine scratches still appear, but the surface does have a mirror finish.
 

Herman, Thanks for your thoughts. I will look at the state of the honing wheel and see if some honing compound is needed.

You continuously apply small amounts of honing compound during any sharpening session. A small application of honing compound will, for me, last for about two or three tools before another application.

I was talking about applying a small amount of oil to the leather on the honing wheel. This is done only once for a new honing wheel, but if a honing wheel has been sitting unused for years, it may have dried out and be in need of an application of a small amount of oil. You want the leather to cut the steel, or more specifically, cut the steel burr off the edge. It therefore cannot be saturated with oil. I had too much oil on mine years ago and had to scrape it off. I now know better.

I have ordered the new 'US-105 Universal Support with Micro Adjust' and the 'TT50 - Truing and dressing tool'

Those are both good investments, Richard. If I had it to do it over I would buy a new US-105 rather than modify my older version. But that was 15-20 years ago and I had a different spending mindset in those days.

Hello!
Happy to make my first post here.

Welcome!

Since I had in my possession many old tools I used the T4 to regrind and re-profile many old neglected or damaged tools.
4 axes, 2 drawknives, 3 planes, ~25 gouges, ~10 mora knives plus some more light sharpening of knives during those months.
I realized that the diameter of my SG stone is now 175mm.
Does this wear seem more than expected?
I realize it is a general question but keeps bothering me...

The analogy I like to use is with brake pads. Yes, they will wear as you brake your vehicle, but they are engineered to do that.

Maybe I am putting too much force and wear the wheel more than I should?

No, more force will just mean you spend less time removing the steel, but it will still be the same amount of wear.

Note that a driver's bad habits (jack rabbit starts and the resulting hard braking) will cause more wear on the brake pads. The only bad habit that will cause too much wear on your grindstone is infrequent truing. Like Ken said, truing often means much less material will be removed from the grindstone than infrequent truing. This is because having an out-of-true grindstone accelerates the uneven wear. For example, say one side of the grindstone has a bit larger radius than the other side, causing the grindstone surface to rise and fall as it rotates during the sharpening process. As you continue to sharpen the low side gets even lower because of the way the tool digs into the grindstone as it begins to rise. Thus, frequent truing requires the removal of less material, not just during any one truing session, but overall for the life of the grindstone.

Just a note to say these comments were very helpful in my work to start using a SuperGrind 2000 machine we have in our community workshop

I also have a SuperGrind 2000 purchased new in 2002. I'm on my third SG-250 grindstone and my third tube of honing compound. Note that if your honing wheel is extremely dried out from not being used for several years, apply a very small amount of mineral oil or the like, but don't overdo it. The honing compound has oil in it, so this is a one-time thing.

As the years passed I noticed improvements in jigs, new jigs, new accessories, and modifications coming out. Some I've purchased but others I've just taken the ideas and used them to modify the existing equipment.

For example, the new truing tool is far superior and very well worth the cost.

Two modifications I made: I hot-glued a couple of neodymium magnets to the outside of the water trough to catch metal filings and prevent them from recirculating.

I modified the Universal Support Bar (USB) by threading the 12-mm shaft, filing flat the side facing the tightening knob, and used bondo to cement a nut into a used juice cap. See the newer Item # TOR-US105 for an understanding of all this.

Hello Herman,

I was able to remove the old paint (it might have been powder coating) with paint stripper. I watched some YouTube videos about rust removal with electrolysis. I'll give it a try. Thanks for the tip!

I also thought that it was powder coating but was later advised that it is paint. I never verified that. Please let us know how the electrolysis works out, I'm very interested. On the really rusty parts I think I removed the worst of the rust with sandpaper or steel wool, then spot primed with a brush using that special paint that bonds with old rust. I had some left over from some previous project.

Unfortunately, my main shaft is also unusable. I also ordered an MSK-250.

You'll be glad you did. I have only one grindstone so I'm not taking advantage of the EzyLock to change grindstones, but I do to remove the grindstone after every session. I just grab the knob on the honing wheel and then push or pull on the grindstone with my other hand, in whatever direction tightens the honing wheel knob, and the grindstone is instantly loose.

I actually wanted to paint the SG2000 green again. Seeing your Tormek, I think mine will be black, too.

Andi, I just painted mine flat black because I had a rattle can of that again left over from some previous project, but whatever color you choose I recommend a semi-gloss or satin finish rather than flat. On the other hand, flat paint makes the telegraphing of ridges around the old rust spots less apparent. Depends I guess on whether you want to go for easier cleaning or better looks. 

I had a 34-year career as a full-time college-level instructor. This is NOT the way to teach. The late great Arnold B. Arons of physics teaching fame, who was not only a professor of physics at the University of Washington, but was also widely-known for conducting  workshops for secondary school teachers, had a maxim: "First the thing, then the name of the thing".

The general idea here is that you first demonstrate or teach whatever the point of the lesson is, and then you follow that up with a more formal discussion of the concept that includes the details. In the case of a tool or jig like the MB-100 this is not to be taken literally. Of course you can start out with the name of the tool, but the point is you first show how to use the tool for the purpose for which it is intended, and then you follow that up with a more in-depth discussion of perhaps its use and the benefits, purpose, and intentions of its use.

For an example of what I'm talking about just go to YouTube and do a search for my name. The first hit you will see there is me demonstrating the use of an early protype of my version of the knife sharpening jig first inspired by Ionut here in this forum. In fact, Ken has made the associated thread that discusses the early adventures with this jig a sticky in this very sub-forum.

This is a discussion of a general issue, like Dutchman points out, about virtually all of the Tormek lessons. But of course it applies to many other how-to videos, especially many of the YouTube videos that are either professionally produced or just made by a user.

The lesson starts out with a discussion of hollow grinding versus flat grinding and teaches the difference between concave, convex, and flat. And several other topics all tangentially related to use of the MB-100, but the relationship of the discussions to the use of the MB-100 are perhaps not apparent to the viewer, resulting in boredom. Use of the MB-100 is the point of the lesson, so get on with it already before the viewer is bored to the point of impatience. We learn best when we experience positive emotions like keenness to learn, not negative emotions like boredom and impatience and the anxiousness of waiting for the instructor to get to the point.
 
The viewer has to sit through a long discussion of general issues before the main point of the lesson is even made.