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Messages - cbwx34

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1681
Knife Sharpening / Re: Knife tip grinding - To Pivot or Not To Pivot
« on: August 15, 2017, 03:20:18 pm »
Hello Ken, Jan, Herman, Rich and the new sharp guys.
Apologies for being offline for so long, was too busy establishing my knife grinding business.

Appreciate reviving my topic I wrote when was new to Tormek.

The main conclusion drawn from that little study is the contrary effect of the blade taper towards the tip and upward curvature:
Because of blade thinning towards the tip grinding angle drops and contact with the stone extends and bevel should widen. However, the belly upward curvature brings the tip towards the support, increasing the grinding angle and compensating for the taper, and therefore the bevel height doesn't noticeably change.
Thanks to that for knives with a normal sweeping curve, no need to pivot/yaw.

Both the Tormek manual section on knife grinding and Jeff Farris video are (...how to say) ...if you think they are right you are still about a dozen fucked up edges far from the right technique.

Hey wootz... thanks for responding (glad you didn't mind your thread getting resurrected). :)

Doesn't Jeff's video basically support your "no need to pivot" position (for most knives at least)?

I also think that, in addition to where the knife is on the stone in relation to the support affecting the angle... the relationship of the belly/tip becoming more of a "side angle" (what I described earlier) also affects it.  This is another reason why the placement of the knife in the jig is so important.  (There has been a lot of discussion on other guided sharpeners... on how the angle can change in the "belly to tip" area... based on how the knife is clamped in relation to the pivot point... and can change quite dramatically once the blade starts to curve).

Basically, I think that, if you're going to pivot the knife... setting the knife in the jig so it maintains the same line (or point) on the stone is important... if you lift the handle, you set the knife in the jig to maintain the angle as the relationship of the knife to the stone changes... not only in relation to the line on the stone... but as the angle "rotates" to the side.  And, as you stated in your original post... different shapes/types of knives require a combination of these, or even a modification to achieve the desired result.  (Sharpie is your friend). :)

1682
Knife Sharpening / Re: Knife tip grinding - To Pivot or Not To Pivot
« on: August 15, 2017, 03:30:23 am »
Thanks for the info. (I survived the whole thing). :)  Couple of thoughts/questions...

You said lifting + pivoting gave the best result... what differences did you see in that vs the other ways?  You are right, regardless of method... the placement of the knife in the jig is key.

As for bevel width... I agree with what you said, about looks vs. performance, but in a commercial sharpening setup... looks probably take precedent in most cases.  You're not going to convince most people (or even have the time to if you do a lot of knives) that the knife "looks funny, but will work better... honest".   So, to some degree (pun intended), things need to look good.

I'll have to digest the numbers.  Good documentation though... thanks.

1683
Several years ago, Ionut, a very experienced forum member, posted about the gap. His solution was to place an electrical cable tie through the hole in the TT-50. He posted a lengthy explanation.

I had not experienced this difficulty, however, as I regard Ionut highly, I placed a cable tie on my TT-50. It eliminated the gap. I had the tie on for several years before removing it. For me, the TT-50 seems to work with or without the tie. If I ever encounter the difficulty, my first line of defense will be to place a tie.

Ken

Here's the ionut post I believe...

https://www.tormek.com/forum/index.php?topic=1077.0

(I usually track down referenced posts to learn more... figure might as well post 'em if I find 'em). :)

1684
General Tormek Questions / Re: Knife Talk (Podcast)
« on: August 14, 2017, 01:25:31 pm »
Yes, that's it.

1685
General Tormek Questions / Knife Talk (Podcast)
« on: August 14, 2017, 05:35:23 am »
Anyone listen to the podcast... Knife Talk?  A guy who chats with different knifemakers for ½ hour or so.

(Oh yeah... it’s sponsored by Tormek).  ;)

1686
With all this “truing” talk  :) ... it made me take a close look at my stone.  I keep it in pretty good shape using a DMT XXC stone (braced against a USB... works pretty good, at least for knife sharpening), but had a couple of spots a bit out of whack... so decided to use the Truing Tool (old version), and clean it up a bit.

Worked fine, but wanted to point out that after truing and grading the stone fine, I remarked the stone with the angle markings... but noted that the old markings were still faintly visible (see attached pic... also made the marks a bit more accurate).  Thought it was a good indicator that if the stone is kept in decent shape... very little material is actually removed in the truing/grading process... (it seems like a lot in the water  :o ).  (I’m sure a bit of Sharpie soaks in... but doubt it’s very much).  Just thought it was an interesting observation.

1687
Hatchcanyon.... very nice, and some good ideas.

1688
General Tormek Questions / Re: Motorized TT-50 Truing Tool
« on: August 12, 2017, 05:50:25 pm »
Quote from: RichColvin link=topic=3339.msg20136#msg20136  date=1502548016
I've been thinking of motorizing my TT-50 truing tool.  The thinking is that it would allow it to run slower (I sometimes get impatient and run it too fast). It would make it run consistently, and I can enjoy a cup of coffee whilst it runs ("Look ma, no hands!").

Rich

That sounds pretty cool!

(Bonus points if you can get it to run a sharpening jig back and forth)...  ;D

1689
The truing tool is one thing I'm still getting frustrated with.... I'll get half way through the wheel with no problem, then the other half chatters so much it leaves patterns in the wheel, forcing me to take another pass and waste more stone  :(

I've tried going lighter passes, deeper passes, faster, slower.... Can't figure out what the common denominator is when it decides to do it and when it decides to work fine

You might take a look at this thread... has some tips that could help.

https://www.tormek.com/forum/index.php?topic=1353.0

1690
Knife Sharpening / Re: Knife tip grinding - To Pivot or Not To Pivot
« on: August 12, 2017, 12:20:10 am »
Herman, thanks for the additional info.

Jan, still don't see it, but I'll ponder your posts.

Ken, that video you linked to actually claims you can't just lift the handle without also pivoting the knife (around 3:42)... not a position I support.

Thanks to all. :)

1691
Knife Sharpening / Re: Knife tip grinding - To Pivot or Not To Pivot
« on: August 11, 2017, 04:30:41 pm »

Wootz has been striving to keep the width of the bevel face constant. He achieved this goal by lifting the handle without pivoting at the expense of maintaining constant edge angle. He admits that the edge angle set at the heel to 30° has increased to 34-42° near the tip! 

I am convinced that using suitable trade-of between handle lifting and blade pivoting would not increase the edge angle so much.

The water flow over the edge is for me another reason to pivot the blade. When the blade is pivoted so that the outer normal of the blade in the belly area is perpendicular to the stone shaft, then the water flows symmetrically over the edge. This is good to achieve. My hands do it unconsciously.

Jan

How so?.... If bevel width is the goal... I'm not sure either method would result in a better angle result... seems to me it would have to be the constant to keep the bevel width the same.  (It's the same result you see on production knives... nice looking bevel, but steep angle, and most of those are freehand sharpened).

Although I primarily sharpen with the wheel turning away... I do use the water as an indicator of where the wheel & blade are contacting... I can do it with either method.  Like you indicated, it's not the primary way though... you can usually feel it.  But I can see the water 'travel' along the edge, especially as I lift the handle to the tip... good indicator of when it's reached.

1692
This is one thing I like about the Tormek... mine is over a decade old... I've been a bit 'neglectful' in maintenance... yet it has never caused me any issues.  (I am better now). :)  Everytime I fire it up... it's good to go.


1693
Knife Sharpening / Re: Knife tip grinding - To Pivot or Not To Pivot
« on: August 11, 2017, 02:35:16 pm »
I do concede that the jigs radius may have been so that the knife could be pivoted (yaw) (although I feel in use it's more of an afterthought). :o

Setting that aside though, I think lifting (roll) can achieve the same result... and, to me anyway, fits the design/setup of the knife jig.  (The Jeff Farris video is what I was referring to earlier).  The change in angle by changing the point of contact on the stone, can be offset by the "side" angle you create by jig placement.

Herman, I have not overlooked your setup.... I think it's a good one, and will probably be my next venture.  I do have a couple of questions... do you ever have an issue scratching/scuffing the side of the knife?  With other platform based sharpeners, that's often the case, but it's also because the 'swarf' can get on the platform, which may not be an issue with the Tormek (since it's for the most part washed away).  Also, when you set the angle, do you compensate for the angle of the blade itself? (Not the bevel, but the actual angle of the blade grind).

All in all, I think Wootz was onto something in his original post.. that pivoting the knife introduces more factors than merely maintaining the same point of contact on the stone... when using the jigs.


1694
Knife Sharpening / Re: Lasers & the Tormek
« on: August 10, 2017, 04:00:16 am »
I'm interested in understanding more about how lasers get used in sharpening on the Tormek.
  • what type of laser do you use ?
    • where did you buy it ?
    • how much did it cost ?
  • how do you mount it for use ?
    • is it attached to the Tormek, or to the bench ?
Pictures would be great !

Kind regards,
Rich


The laser I'm using, and a few pictures are in  this thread...

https://www.tormek.com/forum/index.php?topic=3329.0

... it has a magnet in the base, and I just stuck it on the side of the USB, as seen in the pictures later in that thread.  (That particular USB is flat on one side, so it stuck there no problem).

Here's a link to the laser I use on Amazon...

https://www.amazon.com/Black-Decker-BDL220S-Laser-Level/dp/B000B8GBBS/ref=sr_1_1?ie=UTF8&qid=1502330179&sr=8-1&keywords=bdl220s

I've attached another picture which shows how I use it.  (In this picture I had the laser attached to a clamp, before I figured out I could just stick it on the USB).  Basically, the laser establishes a line on the stone, that I match up to the angles I have (pre)marked on the side of the stone.  Then when I turn the stone on, I hold the knife level and use the laser line to sharpen at the angle I have it set at.

Hope that helps?

1695
Knife Sharpening / Re: Knife tip grinding - To Pivot or Not To Pivot
« on: August 09, 2017, 07:00:25 pm »
Hope you don't mind an "old thread" revival... (remember, I asked)....  :)  but there's a lot of good info in it.

First, a picture to refer to (you can click on it for a larger view)...



First thing I wanted to point out, that when pivoting the blade (1 & 2 in the picture),,, on smaller blades it won't necessarily allow the belly/tip area to reach the LOC... but will drop below it.  So, length of the blade matters.

Second, depending on the setup, when you pivot the blade, you can actually "ride up" on part of the clamp (picture 3).  Can be avoided, but something to watch for.

The main reason I brought this thread up though, is honestly, even after reading thru this and the other related thread referenced... I've never been totally convinced that the original intent of the knife jig was to pivot the blade... but to merely lift the handle to follow the belly to tip area.  In part, based on Jeff Farris' video saying, lift don't rotate, (in fact he makes a point that pivoting is incorrect) and in part, it just doesn't seem a natural movement on many knives.  I understand the purpose... pivoting makes an attempt to maintain the same LOC... so the angle will stay the same... but am not really convinced that the curve of the stop on the jig was designed for this.  (I would swear that it wasn't even mentioned in the old manual... but maybe it's just Jeff's voice stuck in my head). :)

Lifting on the other hand, will also allow you to keep the same angle, depending on how you set up the clamp, (as seen in Jan's picture in this thread, although the pivot point would change), and to me, seems to be a more natural way to follow the shape of the knife when using the standard jig.  I try to illustrate in pictures 4 & 5... that when you lift the handle, you also change the orientation of the bevel in relation to the wheel... so that the angle is no longer totally dependent on where it is on the wheel, but also includes the "side angle" of the bevel in relation to the wheel.  Think of the extreme... if I stood to the side of the Tormek and sharpened a knife on top of and parallel to the wheel (doesn't have to be on top, but easier to visualize)... the angle would totally depend on the angle of the knife.  So, when setting the knife in the jig, by adjusting the belly/tip area closer or farther from the pivot point of the jig, this angle can be altered so that, even by merely lifting the handle...  the same (or at least similar) angle can be maintained throughout.  So, if you clamp the blade where the handle is lifted higher to reach the tip, you increase the angle... and the opposite if you clamp farther away from the tip.

It seemed in reading thru this thread, that the main focus was keeping the angle the same based on the LOC... and not what I'm describing.  And, obviously, I'm not saying pivoting doesn't work, (and it of course is the answer for freehanding where the blade is held level, or for Herman Trivilino's setup, etc.)... but I'm of the mind that with the standard jig setup, lifting the handle in many cases, may be the better option.

So, what say y'all?  :)

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