Measuring the height from grinding wheel to USB?

[Perra]

Is there anyone more than me who had difficulty measuring the correct height of the grinding wheel to the Usb? I had difficulty measuring straight against the grinding wheel and wanted a 90 degree surface to measure against instead. I have searched for suggestions and tips but not found anything where you measure with calipers etc.
So it became a prototype like these. I've been thinking about 3D printing one or making in metal.
Any other suggestions or tips!

[micha]

Hi Per,

there are several suggestions which work quite fine. If you have access to a 3D-printer, this may be interesting, too: https://forum.tormek.com/index.php?topic=4726.msg33863#msg33863

[Perra]

Hi Micha
Thanks. I notice that and its a nice solution but its hard to read under 1mm. i will have a way to use a calliper, but maybe i miss anything?

[micha]

Maybe you just miss the right caliper  .
I use one like that in the picture. (If you want a bigger 'foot', you could easily add a 3d-printed one.)

[RickKrung]

All those devices seem more difficult than they need to be.  I think the challenge is aligning the measuring device (ruler, square, caliper, whatever) parallel between the centerlines of the grinding wheel axis and the USB, both of which are 12mm diameter.  The difficulty is presented by the much larger diameter of the EZ-Loc nut, thus the contrived devices to bridge that difference. 

I haven't found the original post here on the forum, but quite some time ago the notion was presented to stretch a rubber band over the USB and the exposed part of the shaft.  This provides a "sight line" that is parallel.  Then place the measuring device on the USB and touch the surface of the stone such that the device is aligned parallel with one side of the rubber band.  I know this has been presented on a few occasions previously, but here it is again.  It is easy, fast and doesn't require any special devices, other than a rubber band and a measuring device, the latter of which is required already.  It also serves to place the tip of the measuring device at the right location on the grinding surface such that it is "perpendicular", which the OP's device is trying to do. 

BobD's photo of a rubber band (two) stretched across the USB and shaft.


An adjustable square/ruler placed parallel with the rubber band.  Setting the scale in the square to the desired distance, adjust the USB height/distance until the scale rests on the stone and is parallel.


Calipers (you have some similar) doing the same thing but being able to measure to a more precise distance, although many feel that level of precision is irrelevant. 


Woodworker's marking gauge, modified by removing the cutting/marking wheel.  I have the calipers shown in the photo above, purchased for measuring the USB height to the top of the machine case, but I found that method to be a lot more bothersome than necessary.  I didn't like touching the grinding wheel surface with the end of the caliper, due to potential damage to the precision instrument, which is why I went with the making gauge.  I set the marking gauge protrusion using a digital caliper, however, so I am getting close to the same accuracy.  Sometimes there isn't quite enough shaft protruding from the EZ-Loc nut and really what I'm doing is catching the rubber band on the very small bit of thread sticking out.  When that occurs, I just remove the EZ-Loc nut, make my setting, remove the rubber band and replace the nut (See the first photo by BobD).


Rick

[Perra]

Simple solutions are usually the most widely used. Smart ide with a rubber band. I agree that it gets a little "nerdy" with precision in several decimal places. But sometimes it's just fun to solve problems. I both grind and hone with the knife stuck in the jig and then it will be interesting to get the right angle also on the honing wheel, usually added 1-2 degrees. My experience is that the sharpness gets better then when I'm honing freehand. I can contribute with a CAD image where I measured how little it differs if you measure at the rubber band in relation to measurement in the center line. 0.145mm

[GeoBoy]

Go to ultimateangletool.com , wouldn't this help?

[cbwx34]

Is there anyone more than me who had difficulty measuring the correct height of the grinding wheel to the Usb? I had difficulty measuring straight against the grinding wheel and wanted a 90 degree surface to measure against instead. I have searched for suggestions and tips but not found anything where you measure with calipers etc.
So it became a prototype like these. I've been thinking about 3D printing one or making in metal.
Any other suggestions or tips!

While I think that, after a bit of practice, it's not difficult to hit the same spot on the wheel(s), I don't see anything wrong with your idea.  I think it's similar to the "ultimate angle tool" GeoBoy linked to.

You might try some of the other ideas in the thread, for example, the rubber band is pretty easy to do.  But if your idea works for you, looks to me like it'll work.

Simple solutions are usually the most widely used. Smart ide with a rubber band. I agree that it gets a little "nerdy" with precision in several decimal places. But sometimes it's just fun to solve problems. I both grind and hone with the knife stuck in the jig and then it will be interesting to get the right angle also on the honing wheel, usually added 1-2 degrees. My experience is that the sharpness gets better then when I'm honing freehand. I can contribute with a CAD image where I measured how little it differs if you measure at the rubber band in relation to measurement in the center line. 0.145mm

Don't get caught up in too much precision, consistency is in some respects more important than accuracy, and quite frankly, none of these methods are that precise.  You'll get great results without being concerned with "several decimal places" accuracy.

[Dutchman]

...
Don't get caught up in too much precision, consistency is in some respects more important than accuracy, and quite frankly, none of these methods are that precise.  You'll get great results without being concerned with "several decimal places" accuracy.

I totally agree.
For me it remains a "simple method" that is more accurate than the anglemaster even if the usb-to-stone distance is measured with "only" millimeter accuracy. My method, as illustrated in the photo, is completely satisfactory. (for me at least  )

[Perra]

I'm not going to argue with you,  I agree with what you're saying. Thanks for the wise words and interesting tips. I appreciate it.  In my own excel file, I actually round the values to full or half mm.