tool for checking grinding wheel to support bar alignment

[Ken S]

I believe the best way to deal with misalignment of the universal support bar is to use the Tormek Parallel Set Up Tool. Used properly, this tool insures the grinding wheel is parallel with the universal support bar, and that the grinding wheel is flat.  This simple device can be used at two distances.

Tormek calls this tool the TTS-100 Turning tool Setter.  As of this writing, it costs approximately $34 US and is available at any Tormek dealer. Its use quickly becomes second nature.  Used with the Angle Master, it increases tool set up time and repeatability. Good light is imperative for accuracy.

Set the distance from the grinding wheel to the Universal Support Bar using the TTS-100 just like with turning tools. I prefer to use the "A" setting (a shorter distance).

Once the distance is set, use the TTS-100 in the same way near both edges of the grinding wheel to check for parallel.  Checking several points along the wheel will also verify that the wheel is flat.

Reestablishing the distance is easy enough to do, however, I prefer to leave the Universal Support Bar set. I have two support bars and each has an extra micro adjust nut.  The second nut serves as a lock nut. The US-105N Adjusting Nut presently costs $7.52 US. That's an expensive lock nut, but it matches the thread.

With the distance set, place a chisel in the SE-76.  Set the projection distance using the TTS-100, as you would a turning tool.  Unfortunately, the TTS-100 does not have a 45mm projection distance setter. This would allow setting a 25 degree angle bevel for a bench chisel or plane. This is easily remedied by using a piece of cardboard with a line drawn parallel at 45mm, or whatever projection distance gives you the bevel angle you desire.  Eventually you will want to replace the cardboard with something more sturdy.  A piece of plywood roughly 150mm x 150mm (6x6" for those of us still using the "English" measuring system) with a cleat on the bottom surface to hold it against the bench and a small piece of wood set back from the edge to match the bevel angle will do the job.  Several angle pieces may be set and marked.

Any changes for different bevel angles are done by altering the tool projection length.  Leave the grinding wheel to support bar alone.  It is set, parallel and the wheel is known to be flat.

With the support bar parallel with the grinding wheel at a consistent distance, all that is needed for the next tool is to pop it into the SE-76 using the projection "jig".  No measuring is needed.

Ken

[RobinW]

Ken -

Your suggestion triggered something in my brain, so I have a variation to suggest, which I have just tried.

When the wheel has been trued with the truing jig, and the usb is lowered down on to the wheel surface, these two items should be absolutely parallel with no light showing between them.

However when the usb is raised to the appropriate height for sharpening say a chisel, there is play between the usb and the sockets and clamps, and no proof that the usb remains exactly parallel to the wheel surface.

So fit the SE-76 with chisel to the usb. Using the angle master on the chisel, set the height of the usb to the correct height for the desired grinding angle (normal procedure), and with the usb clamps still loose, remove the SE-76 from the usb. The usb is held at the correct height by the micro-adjust screw.

Now slide the SVD-110 Tool Rest onto the usb, with the short side of the SVD-110 towards the wheel. Let the edge of the SVD-110 rest on the wheel and check for light showing between the two.

You now slowly tighten the two clamps for the usb, applying pressure as required to the usb so that when it is fully clamped the usb remains exactly parallel to the wheel surface.

*It was interesting to see how error was introduced when tightening the two usb clamps.*

Remove SVD-110 and refit SE-76 and start sharpening.

The overall accuracy depends on the cumulative machining tolerance of the SVD-110 and the SE-76, but this method ensures that the usb at the sharpening height remains parallel to the wheel surface.

[kennyk]

I'll give the 110 method a try tomorrow.   

I've still got problems with truing the wheel.  when I was trying to true it, the outer edge (EZY lock side) always falls away, about 1/4 - 3/8" in.     

I've noticed that the first inch of my USB is slightly tapered. is this normal?

[Ken S]

Good job, Robin!  Nothing helps an idea like an improvement.  While using the TTS-100 will work, your idea of using the SVD-110 works for a wide choice of distances between the grinding wheel and the support bar.  The TTS-100 limits the choice of distances to two. That's one of the best parts of this forum; good ideas get a chance to become better ideas.

Kenny, I checked my USB.  It is ever so slightly tapered at the end.  One thing comes to mind.  An earlier poster had trouble with his support bar.  The problem ended up being that he had the incorrect support bar.  His unit was the larger T7 size and his support bar was designed for the smaller T3 size unit.  I measured my support bar.  The long dimension is twelve inches.  I don't believe that is your problem, but it is easily and quickly checked.

Ken

[Rob]

I've noticed that the first inch of my USB is slightly tapered. is this normal?

Isn't the taper to help the sliding on of the jigs (SE76, truing tool and elliptical gouge grind jig)?

[RobinW]

My usb is 12 mm dia over all its length. The last 9 - 10mm is 11.5mm dia and a wee bit rough as if plating had come off. It looks as though something had been screwed on - but can't think what and how I have abused that part. It wouldn't affect anything.

I haven't tried any of the jigs, but I don't think I have anything operating over the last part of the usb.

[kennyk]

regarding the 110.   there's around 3mm of wiggle room inside the mounting hole. That's far too much play on mine to give any meaningful results, and far more than the play on the support legs.

[Ken S]

Does your 110 have any play when it is clamped down?  The play may be to allow the patented tapered "Torlock" to work.  Try snugging the 110 enough to hold it in place, but able to be moved to be next to the grinding wheel.  Once it is in place, finish tightening it.  If this doesn't work, something is REALLY wrong with it.

Ken

[kennyk]

no it's fine when it's clamped down.  however it's no good to check if the bar is parallel given that I can move it  3mm before I clamp it!