Help with large curve

[pendo]

Hello all,

As a new T4 owner (~2 months), I'd consider myself somewhat happy overall with my purchase.  While I feel it's a fine machine, I think the amk-75 would've been a better choice.  But I haven't added the Japanese stone, yet, so I'm still hopeful.

I have a question about a specific knife, though.  I own a spyderco parata.

I cannot for the life of me figure out how to jig this thing to where I can maintain a reasonably consistent angle.  Any suggestions?

[micha]

Hi Jason,

a knife with such a distinct curve will certainly need some pivoting.
There have been some very clever ideas for doing so.

You'll find some ideas here: https://forum.tormek.com/index.php?topic=3541.msg24461#msg24461 or here: https://forum.tormek.com/index.php?topic=3802.msg25365#msg25365.

Pivoting can help a lot, but sure needs some practice, so I'd probably not start with the Spyderco.

Mike

[cbwx34]

Hello all,

As a new T4 owner (~2 months), I'd consider myself somewhat happy overall with my purchase.  While I feel it's a fine machine, I think the amk-75 would've been a better choice.  But I haven't added the Japanese stone, yet, so I'm still hopeful.

I have a question about a specific knife, though.  I own a spyderco parata.

I cannot for the life of me figure out how to jig this thing to where I can maintain a reasonably consistent angle.  Any suggestions?

Micha is right... the collar on the Tormek Knife Jig won't work well with that knife.  A "pivot collar"... something that reduces the sides of the Stop Collar is the easiest way.

There are a couple of "commercial" options available:

https://schleifjunkies.de/en/produkt/pin-pivot-collar-2/

http://knifegrinders.com.au/11Shop.htm (although not in stock... but says he's doing a run this month).

You can also use a shaft or stop collar like this:

https://www.mcmaster.com/shaft-collars/clamping-shaft-collars-9/system-of-measurement~metric/for-shaft-diameter~12mm/

will also work.  Basically any way to reduce the sides of the collar on the Tormek, so you can consistently and smoothly pivot the knife.  (For another example, some have taken the stock collar and cut it down).

To help set the knife in the clamp, draw a line across the stone, then set the knife in the clamp so that when you  pivot the knife, it stays close to the line... so that when you sharpen, you'll have a consistent angle/edge.

There are other options, if you're experienced, for example you can remove the stock stop collar and sorta freehand it,,, the key being stay at the same location on the wheel.

This picture shows an example...



... the bottom three, with the collar on, the knife won't stay close to the line, the top three, with the collar removed you can stay on the line.  (Which brings up using a laser)... 

Welcome to the rabbit hole! 

[Hannsi1957]

@CBWX34 u forgett my shop
simpel and easy and cheap Pin Pivot

https://schleifjunkies.de/en/produkt/pin-pivot-collar-2/


cheers Hanns

[cbwx34]

@CBWX34 u forgett my shop
simpel and easy and cheap Pin Pivot

https://schleifjunkies.de/en/produkt/pin-pivot-collar-2/


cheers Hanns

It was there....

[Hannsi1957]

 

i am to old for this all 

[pendo]

Hi guys,

I figured the forum would have emailed letting me know I had responses, but I guess not.  Sorry for being late to respond, but thanks for the input.

I've watched so many different videos on the tormek, I had a pretty good idea that this was going to be a challenge.  I am definitely planning on getting some new hardware for it, and a pivot jig is on the short list.  The Japanese stone is first on that list though.  (I really don't like the leather wheel)

After doing a bit of "air sharpening" I came up with a clamping location and pivoting movement that tries to keep the contact point at the same distance. I then tried it for real, and it wasn't very pretty, lol.  But it's not horrible, either. 

@cbwx34, I never thought about removing the collar.  I think that will be the best method.  I have a Ken Onion with belt grinder attachment at work that I seem to be competent with (everybody asks me to sharpen their knives for them) so I am comfortable with freehand.  I can picture how this could work pretty well. 

Thanks again for the suggestions!