a new angle setting tool

[Ken S]

Herman,

I placed my platform jig and scissors jig side by side through a universal support bar today. The platform jig stands about 22mm or 7/8" higher than the scissors jig. That is a substantial difference.

Ken

[WolfY]

Thanks for the visual explanation too.

[Herman Trivilino]

Herman,

I placed my platform jig and scissors jig side by side through a universal support bar today. The platform jig stands about 22mm or 7/8" higher than the scissors jig. That is a substantial difference.

Ken

When I did this a couple years ago I measured a difference of 24 mm.

http://forum.tormek.com/index.php?topic=1592.msg10009#msg10009

[Ken S]

Herman,

Everything is bigger in Texas. 

Ken

I made a quick measurement. You are probably correct.

[WolfY]

Yesterday I had the opportunity to test the T-2. For those who looked at it and the permanent jig that is part of the system, would recognize the same platform idea that Herman use.
The only difference compared to water stone system is the consistency of the stone diameter. That is not a big problem as it changes very slowly.
Pros. Cons. And thought another time and thread.
But... I'm still for the wet stone system 

[Ken S]

WolfY,

I will be interested to learn more about the T2. I realize it is a very specialized machine, but I am curious.

What are your observations about the honing wheel on the T2?

Ken

[WolfY]

Ken, are you sure we want to continue it on this thread?
I rather open new one for the T-2. When back home.

[Ken S]

Good thought, WolfY. That would be less co fusing.

Ken

[RickKrung]

Jan,

I realized the point was for automatic diameter correction. I assume the point will be equidistant between the wheels.?

Ken

Yes Ken, you are correct. The position of the pivot point (shown as red dot) is better visible in the 2D drawing below:



Because this pivot point is beyond the setter base, the solution is not easy. E.g.: the rotary arm of the WolfY's setter may be guided by two concentric rings with the centre in the pivot point.

I am really afraid that this is too complicated for the majority of forum members.

Jan

Resurrecting a very old post/thread.  I've been struggling lately with some well discussed issues of setting the USB height and wanting a quick way to set some standard angles. I use a couple versions of angle setting software, but I'm going to be doing some "Farmers Market" sharpening soon (two weeks) and would really like some quick ways of setting the angles.  In thrashing about, I came across this old thread, by way of checking out the jigs on Rich Colvin's site and hunting down posts related to the Hanjig referenced there.  I found Tournevis' post that had a CAD DXF format file attached, but could not open it (errors reported and the open failed).  So I kept cruising through the thread and found Jan's drawing.  Off I go...

I've believe I have faithfully recreated Jan's drawing of the jig in my CAD program, but for clarity, I have omitted the dimensions. 


I drew in the grind stones at 250mm and 200mm and drew the respective tangent lines at the centerpoint between the two metal contact discs.  I determined that the difference between the tangent lines "position" was only 0.32mm separation, which I regard as insignificant to the angles and so have disregarded the difference in wheel diameters over the functional range for a T7/8 machine.


I then drew in angle lines for 10, 15 and 20º from the tangent point mid-way between the two contact discs


I am extremely curious about why my drawing angles came out so different from Jan's, and trusting Jan's skills and knowledge, I question my work rather than his.  Is my assumption about using the tangent from the centerpoint between the two contacts discs in error?  That would depend on the projection used on the jig. 

Edit: Drew circles, one with a radius of 139mm and another through the center points of Jan's USB holes.  The latter measured 133.52mm. 


Checking my work, after the fact.  Looks okay to me.


I would like to hear (read) your thoughts. 

Rick

[cbwx34]

I just skimmed thru this thread... but from what I can tell in this post, the location of the holes isn't determined by the tangent point you referenced...  (Jan will have to explain how he determined the hole location).... so, yeah, I think your assumption is wrong. (or maybe I am).

Maybe I missed it, but this approach never seemed to get out of the testing phase? (Hint)? 

I guess I'm not seeing the benefit of this approach... (doesn't mean there isn't one).  I think a Sharpie would be the quickest route.  Sharpening at a specific angle has the disadvantage in that it takes longer if it doesn't match (at least closely) what the knife is at already.  Anglemaster (or calculator) if you want to check what you're sharpening at.

I guess part of this depends on your goal... but if there's a time constraint... my .02 is... just sharpening a knife at the current angle it's at, 99.9% of the time will come out very sharp, and more than meet the needs/satisfaction of the user.

and another (knife centering) with the standard knife jigs is sort of solved. I'm waiting for a friend to help me with the real prototype. Don't tell anyone

WolfY

Self centering jig?  ( 2016... You're killing me here)... 

[Jan]

Rick, your interest pleases me. You are almost correct in your considerations. 

I have considered 250 mm and 160 mm stones and have found shift of the tangent line 1.4 mm and 2.1 mm respectively.

For a projection length 139 mm the centres of the USB for bevel angles 10, 15 and 20⁰ lie on a circle with radius 133.54 mm.

Your drawing angles differ from my USB positions for bevel angles 10, 15 and 20⁰ by some 5.2⁰, which is an angle given by the geometry of the knife jig and the USB (atan(12 mm/ (139-6) mm) = 5.16⁰).

CB, I guess in my country they are one or two dozens of Tormekers using this setting tool. Some people printed it on a 3D printer. My is metallic. 

Jan

[cbwx34]

CB, I guess in my country they are one or two dozens of Tormekers using this setting tool. Some people simply printed it on a 3D printer. My is metallic. 

Jan

Thanks for the pictures.

I guess I'm swayed by the fact I've never seen it anywhere outside of this thread.

(I do like the 2nd picture, with the setup to set the Projection Distance)...



Still, not really seeing any time savings with this method though (which was Rick's stated goal).  I could calculate and pre-mark the USB height for the 3 angles (based on the current wheel size)... and that should get me thru a day of sharpening at a Farmer's Market.  (I could see the advantage if there wasn't any way to know what the USB height should be).

(Just to be clear, I'm not downplaying the device itself, or the skill required to make it... from that aspect, I think it's pretty cool.)

Edit to add:  From a "time savings" aspect, one thing I've noticed with SteveB's method... is he uses an alternative for deburring and finishing the edge.  For example from his website he uses an "F.Dick RS-150" to finish the edge.  And from his "Boy Scout Jamboree" thread, he used a Sharpmaker to knock off the burr.  (Might be worth looking into).

[RichColvin]

CB,

Rick Krug sent me an eMail and asked me about my experiences with the HanJig.  What I have found is :

• When sharpening a few knives, especially if I swap out the grindstones, the HanJig is the "bees knees" !  This is a very quick setup that really resembles the TTS-100 in its approach.  That is something I use when wood turning, and it gets me back to work fast.
• When sharpening a load of knives (like everything in the kitchen), then the platform method is faster overall.

Kind regards,
Rich

[Ken S]

Rich has shown me his hanjig. It is clever and formidable. My grandson is helping me print one of the 3D jigs from the Czech Republic. They are also formidable!

I would suggest that some of us are not using these jigs in the most efficient manner. Using the example of a farmers market sharpener, there are two variables in setting a knife in a jug: 1) the Distance from the support bar to the grinding wheel and 2) the Projection of the edge in the jig from the support bar.

If these two remain constant, the sharpener may sharpen knives with the same bevel angle (I use 15°) all morning and not need to reset anything.If someone is using a kenjig or other setting jig for every knife, it is for the enjoyment of doing it, not the necessity. Used properly, the setting jig should make sharpening with the Tormek knife jigs almost as quick as freehanding with one of Herman's small platforms. Used skillfully, the Herman platform seems like it might approach the accuracy of the Tormek knife jig.

   I think both are useful, perhaps under slightly different circumstances. I use both.

Ken

[RickKrung]

Rick, your interest pleases me. You are almost correct in your considerations. 

I have considered 250 mm and 160 mm stones and have found shift of the tangent line 1.4 mm and 2.1 mm respectively.

For a projection length 139 mm the centres of the USB for bevel angles 10, 15 and 20⁰ lie on a circle with radius 133.54 mm.

Your drawing angles differ from my USB positions for bevel angles 10, 15 and 20⁰ by some 5.2⁰, which is an angle given by the geometry of the knife jig and the USB (atan(12 mm/ (139-6) mm) = 5.16⁰).

CB, I guess in my country they are one or two dozens of Tormekers using this setting tool. Some people printed it on a 3D printer. My is metallic. 

Jan

Duh!...   Yes, I totally forgot about the knife jig on the USB.  I'll work on updating my drawing.  I am converting it to inch dimensions, as that is what I'm used to, so ultimately, my numbers will differ from yours.  I'm also going to use 5/8" OD bearings. 

I've done all my work in CAD without any math.  I do not understand what you are saying about the "shift of the tangent line 1.4 mm and 2.1 mm respectively".  I can understand that things change with different (smaller) diameter wheels, but I'm not getting enough of it regarding the "shift". 

I have a drawing of the SVM-45 knife jig from another drawing, which I'll port over to this drawing and use it for setting up the angles, etc..

Thanks,

Rick