I've noticed the reading from the BESS measurement device vary according to the rate at which I move when cutting the wire. Quickly cut against the wire and the results show a much sharper knife. I was wondering if anyone made a device with which the knife could be mounted, such as the magnetic one from Schlelfjunkies, however, have it connected to a manual or motorized device which lowers at a constant uniform speed.
Mostly I just sharpen to get a knife usable in the kitchen and or boat. There are times though when I like to "Putz" around and see if a new technique produces better results. If someone or company does make such a device I would be more than thankful for that information.
Thank you for your time.
The BESS tester is just a rough guide to sharpness. It is not designed to provide a repeatable consistent standards based sharpness test. The BESS tester bears no resemblance to a ISO sharpness test.
Your best way is to try to apply the edge consistently as best you can.
There is a device offered: https://schleifjunkies.de/produkt/vorrichtung-zum-exakten-messer-der-schaerfe-mit-dem-edge-on-up-bess-tester/
Regards,
Drilon
In addition, the manual reads :
QuoteYour downward movement with the knife should be slow and deliberate. Try to find a seated
position with arms resting on the worktop for greater control and stability. If you can clearly see the
increase in force tick upward on the display either in 5 or 25 gram increments (depending on the
instrument you have purchased) then you know that you have taken the measurement correctly.
So if you "quickly cut against the wire", you're not measuring sharpness.
Thank you, I shall try.
Drilon and John, thank you. Somehow I never saw the device on the German site.
Quote from: Stovepipe on September 02, 2024, 12:35:39 AMI've noticed the reading from the BESS measurement device vary according to the rate at which I move when cutting the wire. Quickly cut against the wire and the results show a much sharper knife. I was wondering if anyone made a device with which the knife could be mounted, such as the magnetic one from Schlelfjunkies, however, have it connected to a manual or motorized device which lowers at a constant uniform speed.
Mostly I just sharpen to get a knife usable in the kitchen and or boat. There are times though when I like to "Putz" around and see if a new technique produces better results. If someone or company does make such a device I would be more than thankful for that information.
Thank you for your time.
I have one of EOU's BESS testers, and was heavily involved with it use for a while. But I got to where I learned what I needed to know about my sharpening process and now just about never use it any longer and, like you, just sharpen to make knives nicely sharp and usable.
Also like you, I never noticed the device for controlling the testing process. It looks to be decent enough, but it does look like it may still be prone to user variability and would benefit from being motorized or standardized in some manner. Some years ago, I motorized the Tormek Truing Tool (https://forum.tormek.com/index.php/topic,3339.msg22657.html#msg22657) and now use it when truing any matrix grinding wheel (SG, SB, SJ and traditional grinding wheels fitted to the T8). There is a link in that thread showing it use, but here it is directly (https://vimeo.com/270241192). I have more of those motors and more of the threaded rod stock. It could be interesting to make a motorized BESS testing fixture. I have a spare dial comparator granite stand that could serve as the platform/column.
Rick
My introduction to BESS testing was many years ago when Steve Bottorff sent me a now out of production KN100. It held the knife securely. The amount of pressure on the test medium was controlled by the number of BBs in the container above the knife. The procedure was slower, but seemed more accurate than with the present models.
With care, even the least expensive model will identify the presence of some burr. In my opinion, many of the inaccuracy problems blamed of the tester are really the result of poor technique. A fine violin skillfully played can produce beautiful music or noise if played by a poor player. I recently refreshed my BESS knowledge wth study of the sdgeonup.com website. Mike Brubacherand his creware continuing to innovate, even if some of the users Re not keeping pace.
Ken
Rick & Ken, thank you
I guess the fixed rate jigs provide the ultimate reliability, but I find that my results are highly repeatable if I just follow Edge on Up's instructions and go slowly enough to see the numbers advancing one by one. I'd say it should take a minimum of 3-4 seconds, even for a very sharp knife.
From the manual:
"Remember Slow and Easy! We're not chopping carrots (at least not yet!) but measuring the sharpness of an edge. Your downward movement with the knife should be slow and deliberate. Try to find a seated position with arms resting on the worktop for greater control and stability. If you can clearly see the increase in force tick upward on the display either in 5 or 25 gram increments (depending on the instrument you have purchased) then you know that you have taken the measurement correctly. When the test media severs, the measurement is complete and your BESS score for that edge will be shown on the display."
very informative, thank you. I appreciated the difference between the clip and wire spool as I never knew that.
I like these better than that on the spools... Never tried the BESS clips.
Dental Floss.jpg
I'm curious as to what results you get? is it comparable to the spool? Now I'm going to go out and purchase for my own use. Thank you. Very Clever!!!
I believe the dental floss clips may have originally been an influence on the development of the BESS clips. However, it seems to me that flossing and BESS measuring have different product requirements. Dental floss, being used in the mouth, must have stringent sanitation requirements. BESS test filament must have stringent breaking control. Consistent breaking pressure control for dental floss and test filament sanitation seem like secondary priorities to me.
I can see possibility of dental clips as a replacement with the economy tester with 25 gram accuracy. That should provide enough accuracy to detect a burr for home use. Industrial users might require greater accuracy.
One of the skills machinists acquire through experience is sophisticated, consistent touch. I'm sure experienced BESS users like Wootz developed a similar consistency with filament tension and testing technique.
Ken
Guys! The comment about liking the floss clips was strictly in regard to flossing my teeth - NOT - about using them for BESS testing, which would be silly.
The only serious point was that my experience with the floss clips being preferred to the spooled floss is that I actually use the clipped floss, daily like my dentist has wanted me to for decades. In years past, when the dental hygienist offered me a new spool of floss, I'd say, "sure, but I don't know what I'd do with it..." (as a joke, I totally knew what...)
The point about clips vs spooled is that maybe I should try the BESS clips to see if I liked them better than the spooled BESS filament material for BESS testing. I have some clips, but have literally never tried one.
Rick,
And here I thought dental floss made my knives sharper ;D
Ken
In regards to the clips... when I use a clip the results are about 20 points lower than using cutting the media with the stainless platform with the media stretched across.
For me, the BESS tester was life changing in the way I stropped and what compounds I use. It shortened the time I spent honing dramatically as well as making it possible to measure sharpness.
It may not be exact but honestly I do think it's fairly consistent if used slowly as in the directions. I can test a blade in the same spot and get the same readings multiple times.
One thing I saw that will help with consistent results is to use a weight (100g) and a clip to tension the test media. This way the variable of tension is held constant. I would also practice on moving the knife fairly slow, trying to be consistent.
There is a automated BESS sharpening meter sold by Vekato:
https://sharpeningtool.eu/de/catalog/accessories (https://sharpeningtool.eu/de/catalog/accessories).
I did some modification on my own:
- Replaced the clamp arm by a 3D printed arm with magnets to allow higher blades,
- Tuning the stepper driver current settings to give the motor a slightly higher momentum which easily lifts now 1-2kg knives (theoretically a Nema 11 stepper with 0,07Nm should lift 5.6kg) and
- slowing down the downwards speed to 12 rpm giving a cutting speed of 0.4mm/s to ensure accurate measurements,
it's working quite well now.
Not commercialzed but worth to read about another BESS testing apparatus in a scientific style is available under the following link published by Dr. Martin Henschke. It's in German but maybe you find an online translater. I think it's really worth to read.
https://www.henschke-geraetebau.de/dr/Schaerfetester.html (https://www.henschke-geraetebau.de/dr/Schaerfetester.html)