Requesting help with SVM-45 lifting technique

[wanderingwhittler]

I'm attempting to build experience with both lifting and pivoting while sharpening with the SVM-45 Knife Jig. I'm further along with lifting and have a few questions. Expect another thread on pivoting once I figure out what I need to ask.

I'm using a carbon steel Opinel No. 10 for practice, by the way. It has good steel and will take an excellent edge, so I know any deficiencies in the edge are the fault of my technique.

I've been struggling with a couple of things that I hope I can get some tips for improvement.

First, I'm trying to slide the jig along the USB without any pivot, but I'm finding it difficult to do that. Even when working along the straight part of the edge I still often rotate the jig a small but noticeable about side to side as I move the jig. I've tried varying my grip on the jig, but still haven't found what works. Maybe I haven't found the right grip? Maybe it's the amount or direction of pressure? Could body position be a factor?

Second, when it comes time to lift the handle, I'm noticing that, with the collar locked against the bar with my thumb, it stays fixed while the jig rotates. I suppose with perfect technique the jig would rotate back to where it started when I again lower the handle, but I'm concerned about accumulated error introducing a gradual micro adjustment as the sharpening session progresses. Is that a problem in practice? If so, how can it be mitigated or avoided?

Any insight, advice, or tips would be greatly appreciated.

[cbwx34]

I'm attempting to build experience with both lifting and pivoting while sharpening with the SVM-45 Knife Jig. I'm further along with lifting and have a few questions. Expect another thread on pivoting once I figure out what I need to ask.

I'm using a carbon steel Opinel No. 10 for practice, by the way. It has good steel and will take an excellent edge, so I know any deficiencies in the edge are the fault of my technique.

I've been struggling with a couple of things that I hope I can get some tips for improvement.

First, I'm trying to slide the jig along the USB without any pivot, but I'm finding it difficult to do that. Even when working along the straight part of the edge I still often rotate the jig a small but noticeable about side to side as I move the jig. I've tried varying my grip on the jig, but still haven't found what works. Maybe I haven't found the right grip? Maybe it's the amount or direction of pressure? Could body position be a factor?

Second, when it comes time to lift the handle, I'm noticing that, with the collar locked against the bar with my thumb, it stays fixed while the jig rotates. I suppose with perfect technique the jig would rotate back to where it started when I again lower the handle, but I'm concerned about accumulated error introducing a gradual micro adjustment as the sharpening session progresses. Is that a problem in practice? If so, how can it be mitigated or avoided?

Any insight, advice, or tips would be greatly appreciated.

The collar moving "on its own" has been brought up before (a poor redesign in my and others opinion).  A quick solution is to wrap a couple of rounds of painters or masking tape on the jig shaft, then screw the collar on over it.  (That's a recommendation written in a thread somewhere).  It works pretty well, and also eliminates a bit of "slop" the newer jig has, and keeps it from turning as easily.  You can also add a "locking screw" back into the jig (as shown in that Instagram video).  I did it on one by just drilling a hole slightly smaller than the screw, then used the screw itself to "tap" the hole.

I'm not sure about your other question... I hold/control the knife by the handle, and just put pressure on the jig to keep it against the USB, so I'm not sure what you mean by "grip on the jig"?  Maybe that's where the problem is... if you're actually holding the jig to help control the knife?  (Just a guess here).  If so, try just controlling the knife with the hand holding the handle, and only put a bit of pressure on the jig to keep it against the USB, and see if that helps.  (If not, maybe a bit more info will help).

[RickKrung]

...snip...
The collar moving "on its own" has been brought up before (a poor redesign in my and others opinion).  A quick solution is to wrap a couple of rounds of painters or masking tape on the jig shaft, then screw the collar on over it.  (That's a recommendation written in a thread somewhere).  It works pretty well, and also eliminates a bit of "slop" the newer jig has, and keeps it from turning as easily.  You can also add a "locking screw" back into the jig (as shown in that Instagram video).  I did it on one by just drilling a hole slightly smaller than the screw, then used the screw itself to "tap" the hole.

I'm not sure about your other question... I hold/control the knife by the handle, and just put pressure on the jig to keep it against the USB, so I'm not sure what you mean by "grip on the jig"?  Maybe that's where the problem is... if you're actually holding the jig to help control the knife?  (Just a guess here).  If so, try just controlling the knife with the hand holding the handle, and only put a bit of pressure on the jig to keep it against the USB, and see if that helps.  (If not, maybe a bit more info will help).

I agree with CB regarding how to hold the knife, rather than just the jig, if that is what you have been doing.  I think it gives a better position and leverage, not that the leverage is used much for applying pressure, more maintaining position/orientation.  This may be more of a matter of practice and developing muscle memory also. 

I also, largely, agree with CB on the collar.  Tape on the shaft can reduce the little bit of wobble, but I think that wobble is immaterial once you have gained experience in that you are guiding the jig and knife in relation to the stone/wheel and not relying on the collar for that. 

The collar rotating during use and thereby changing the projection distance has been commented/complained about before (myself included), just as CB mentioned.  Tormek apparently abandoned the locking screw in favor of the O-ring due to users over-tightening the screw and stripping the threads.  I think that is an unfortunate and entirely avoidable situation.  I am not sure about it, but it seems to me that the collar rotating might be a matter of too much pressure on the collar against the USB, but I don't know if it is possible to keep it in place without that much pressure.  I'd have to consciously give that a try.   

That is not likely to happen for me, as I have "abandoned the O-ring" and gone back to putting locking screws in the collars (I remove the O-rings as they only get in the way).  I have done this by drilling and tapping the holes using an M6x1 tap.  As a machinist, I shudder at hearing CB's method of using the screw to thread the collar.  While obviously functional, it runs the risk of creating very shallow threads that could easily strip, resulting in the situation that caused Tormek to abandon the threaded locking screw. 

When using the locking screw to form the threads, the created threads would be more shallow and more poorly formed than tapping.  More shallow because a larger drill must be used to give the non-tapping screw a "start" in the hole.  More poorly formed as the plastic is being deformed/pushed out of the way rather than being cut.  But, it is working for CB, so more power to him. 

I believe it is working for CB because he has learned to tighten the screw only enough to keep the collar in place and that it doesn't take as much force as he is capable of.  And this is key, even for when the threads have been cut to full depth using a tap.  That is what I do and have had no problem with the threads stripping.  And if they do, I'll just move the hole to a different location and re-thread.  But moving the hole is not the point or the right solution.  The right solution is to use only enough tightening force to lock the collar.  If that is not enough and the collar still rotates, then definitely too much pressure is being applied to the collar against the USB, IMHO. 

Ok, so back to using a tap to form the threads.  I say, buy an M6x1 tap and use it on the collars.  If you get into this much further, the tap will become quite useful as it is the Tormek GO TO thread for all of the jig locking screws/knobs.  I've used it for securing an extension plate on the Tormek scissors jig base plate to make a platform jig for freehand grinding (see attached image).  I have since cut down that base plate to just 52mm wide and now have another 72mm wide base plate section that can be used for other custom jigs.  I had to D/T an M6x1 hole in the "Tor-Lok" sleeve for the USB locking knob of the platform jig and will have to do so with the extra piece as then one already there is too far off to the side.  In other words, that M6x1 tap is very useful and well worth the modest cost, IMHO. 

Rick

P.S.  In the attached image showing my platform jig, the scissors jig base has not been cut down yet.  I found the attached plate had to be moved to one edge due to interference with the USB vertical leg (also not shown).  I eventually cut it to as wide as the extension plate as mentioned above. 

[wanderingwhittler]

CB and Rick, thank you very much for your insight. You both correctly diagnosed my problem. While I was attempting to position my hands as shown in the manual, I was using the jig hand as the primary source of both pressure and control. After trying again and using the handle as the primary means of control the results were much better. I also think I was applying too much pressure before, which exacerbated the problem.

Rick, your point about muscle memory is well taken. I can see it's going to take some very intentional practice to get me the rest of the way. I'm going to try shortening my practice sessions for the time being so that I can really focus and not let mental and physical fatigue creep in and hinder my learning.

Regarding the collar, thank you for summarizing the past conversations. I figured it had probably come up before, but, even now knowing it has, I haven't been able to find the relevant threads. Collar rotation was much less of a problem once I began using the handle as the primary source of control and pressure. I'm going to see how far I can get by focusing on technique and then will look into taping and/or tapping when I've taken that as far as I can reasonably go.

Thanks for the recommendations on the tap, Rick. Lacking the knowledge of a machinist, I would have tried exactly the method CB described. I do plan to build a platform and perhaps other jigs in the future so I'll go ahead and pick up an M6-1 tap and learn to use it beforehand.

[RickKrung]

...snip...
Thanks for the recommendations on the tap, Rick. Lacking the knowledge of a machinist, I would have tried exactly the method CB described. I do plan to build a platform and perhaps other jigs in the future so I'll go ahead and pick up an M6-1 tap and learn to use it beforehand.

Good luck with all of the practice and learning. I am confident you will do well. 

As for learning to use the tap, get in touch with me privately if you would like some guidance.  That goes for anyone else too. 

Rick

[cbwx34]

...
...As a machinist, I shudder at hearing CB's method of using the screw to thread the collar.  While obviously functional, it runs the risk of creating very shallow threads that could easily strip, resulting in the situation that caused Tormek to abandon the threaded locking screw. 

When using the locking screw to form the threads, the created threads would be more shallow and more poorly formed than tapping.  More shallow because a larger drill must be used to give the non-tapping screw a "start" in the hole.  More poorly formed as the plastic is being deformed/pushed out of the way rather than being cut.  But, it is working for CB, so more power to him. 

I believe it is working for CB because he has learned to tighten the screw only enough to keep the collar in place and that it doesn't take as much force as he is capable of.  And this is key, even for when the threads have been cut to full depth using a tap.  That is what I do and have had no problem with the threads stripping.  And if they do, I'll just move the hole to a different location and re-thread.  But moving the hole is not the point or the right solution.  The right solution is to use only enough tightening force to lock the collar.  It that is not enough and the collar still rotates, then definitely too much pressure is being applied to the collar against the USB, IMHO. 
...

Hahaha... well I'll go with "ignorance is bliss"   But no argument from me... I cringed while doing it.  I can't really say it's "stood the test of time"... 'cause I don't use it much at all anymore.

CB and Rick, thank you very much for your insight. You both correctly diagnosed my problem. While I was attempting to position my hands as shown in the manual, I was using the jig hand as the primary source of both pressure and control. After trying again and using the handle as the primary means of control the results were much better. I also think I was applying too much pressure before, which exacerbated the problem.
...

Glad it's working out! 👍

[wanderingwhittler]

...snip...
Thanks for the recommendations on the tap, Rick. Lacking the knowledge of a machinist, I would have tried exactly the method CB described. I do plan to build a platform and perhaps other jigs in the future so I'll go ahead and pick up an M6-1 tap and learn to use it beforehand.

Good luck with all of the practice and learning. I am confident you will do well. 

As for learning to use the tap, get in touch with me privately if you would like some guidance.  That goes for anyone else too. 

Rick

Thanks for your kind words of encouragement and offer of help with the taps. I'll gladly take you up on it when I'm ready.

Greg

[Ken S]

Greg,

I have not seen the typical starting post listed here. Most of us learned a lot from studying the videos done by Jeff Farris. Jeff was the founder and first moderator of this forum. He did a series of you tubes. Do an online search for Farris Tormek videos. He explains and demonstrates lifting the knife to sharpen the tip area. I highly recommend studying all of Jeff's videos. I still refer to them and continue to learn from them.

Ken

[wanderingwhittler]

Greg,

I have not seen the typical starting post listed here. Most of us learned a lot from studying the videos done by Jeff Farris. Jeff was the founder and first moderator of this forum. He did a series of you tubes. Do an online search for Farris Tormek videos. He explains and demonstrates lifting the knife to sharpen the tip area. I highly recommend studying all of Jeff's videos. I still refer to them and continue to learn from them.

Ken

Thanks for the recommendation, Ken. I'd watched his Knife Sharpening with Tormek. Are there other videos by him on knife sharpening? That one helped with the "what", but I was struggling with the "how" of getting my motion as smooth as his. CB and Rick got me pointed in the right direction.

Incidentally, I've actually found searching through the archives here to be more productive than unguided searching for videos. It's hard to know whether a random video I find is giving accurate information, but I know the information here will either be accurate, corrected by experts, or intelligently debated when there is not consensus.

I do try to watch videos that come recommended here, though. If you or anyone else have favorites for learning solid  Tormek knife sharpening technique, I'd appreciate recommendations.

Thanks,
Greg