Topic: Regrinding knives

Whats the best way to regrind reed knives? I am having a hard time with the Diamond stones.

Thanks!

Share

Re: Regrinding knives

Which Diamond stones are you using?

If you are using the DMT fine or extra fine, it will only do so much so fast. To remove metal faster, you can try changing the position of the blade from perpendicular to the stone to a 45 degree angle to the stone (not raised off the stone). Use this position until a 45 degree scratch pattern is established, then switch back to the perpendicular position. Keep repeating until you've removed enough metal.

If you have access to the coarse, extra coarse or even the extra extra coarse DMT, they will work very well in stock removal for reshaping. Use lots of water.

If you have access to a belt sander, you can use that, too. A #120 belt will do just fine - be sure to keep the blade from over heating by dipping in in water when it feels warm to the touch.

I hope this helps!

If it's that bad, you can always send it to me for reshaping.

Tom Blodgett
Jende Industries, LLC
www.jendeindustries.com

Last edited by Jende Reed Knife (2010-12-26 20:07:27)

Re: Regrinding knives

I was using a coarse, but I had no clue about extra coarse and extra extra coarse. thank you!

Share

Re: Regrinding knives

Video stream of "Reed Knife Sharpening" by Tom Blodgett (owner of JENDE knife) is available on www.idrs.org. To access the video, go to Knife Sharpening video and enter "knife" under "content." (idrs.org login required)

Video description:

Reed Knife Sharpening

Mr. Blodgett’s reed knife sharpening lecture/demonstration will be presented in 4 parts. Part 1 defines and discusses the pros and cons of the 4 basic reed knife blade shapes. Part 2 explains the geometry behind each shape and how it applies to sharpening. Part 3 is a demonstration of how to sharpen each of the 4 blade shapes, and part 4 is left open for questions. This lecture applies to anyone with a reed knife, and is not specific to either oboe or bassoon!

Yoshi Ishikawa
Professor of Bassoon, University of Colorado at Boulder, College of Music
Editor, IDRS OnLine Publications

Re: Regrinding knives

jlfoboe89 wrote:

I was using a coarse, but I had no clue about extra coarse and extra extra coarse. thank you!

The Coarse DMT is better for repairing small chips or more routine shaping, not the major stuff it sounds like you're talking about. You'll need time and the alternating knife positions discussed above. Be patient and use lots of water. You should get an interesting smell from the metal, too smile

The Extra Coarse is better for more serious reshaping in my experience. The XXC (extra extra coarse) DMT is a bit pricier, but it is very aggressive.

What are you using after the DMT?

I haven't seen the IDRS video in a while, but I hope it might answer some of your questions. If not, feel free to ask them here - I lurk smile

Tom Blodgett
Jende Industries, LLC
www.jendeindustries.com

Re: Regrinding knives

I use a shapton 1000 and then a shapton 2000 water stone..

Share

Re: Regrinding knives

jlfoboe89 wrote:

I use a shapton 1000 and then a shapton 2000 water stone..

NICE! big_smile 

You also can try using the DMT coarse to texture the Shapton (and flatten it, even though the DMT is a little shorter in length). Leave the slurry on the 1K Shapton that gets formed with the DMT (which should be whitish). The stone will be more aggressive that way. Do the alternating positions with just enough water so the paste doesn't stick to the stone.

For an even more aggressive 1K stone, place 60 or 80 grit wet/dry sand paper on a flat surface and texture the 1K stone. Repeat as necessary to keep it aggressive (I normally don't like sand paper because of grit contamination, but it makes the 1K quite aggressive, which outweighs the perfection issue at the moment). You can always use a clean stone after the stock removal is done.

I hope these tricks help!

Tom Blodgett
Jende Industries, LLC
www.jendeindustries.com

Re: Regrinding knives

I use japanese waterstones grit 3000 and 10000. These are only for finishing the knives. A 1000 is good for rougher work
These stones are quite rewarding when used correct.
When using a stone keep in mind it has to be perfectly flat. After some time of sharpening the stone has slopes, created by the way we sharpen. These can be very minor but making sharpening a lot more innefective. To check, draw pencil strokes on the stone. Put your stone on a perfect flat surface (a modern thick windowglass is good enough) with a waterproof sandpaper in between (grit 600).  You see immediately where pencil strokes remain telling you that the stone is not flat. Continue in circular movements until all pencil strokes are gone. On these japanese stones this works very well.

Now you can start sharpening your knives!

Share