Replies

1. 
   citrouille | Dec 20, 2006 07:48pm | #1

   Try MSC, I think it's mscdirect.com or Mc Master Carr.

   C.

2. 
   RickL | Dec 20, 2006 07:59pm | #2

   Ditto on mcmaster, MSC. Also Enco, J&L and any industrial supplier. Tage Frid's  book and Leonard Lee's book on sharpening cover that topic and you can do it while the knives are still in the head. The stone is mounted in a router.

1. 
   marti038 | Dec 20, 2006 08:16pm | #3

   Allow me to pub my own employer...

   http://www.fastenal.com

    

    

2. 
   jackplane | Dec 20, 2006 08:34pm | #4

   I would be extremely wary of mounting any stone in a router. At speeds of 18-20,000 rpm this could mean the stone shatters and bits fly everywhere. It's important to note the rpm rating on the bit before installing. 

1. 
   RickL | Dec 20, 2006 11:16pm | #8

   Obviously the stone should be rated for that rpm but it's typical to run those in die grinders which is what they are designed for and those rum 20 to 25 thousand rpm for the 1/4" collet models like Dumore and such.

1. 
   jackplane | Dec 20, 2006 11:27pm | #9

   As in a dremel tool, yes that'd work. The op mentioned a cup brush, which made me think of a large cup brush- with a dangerous diameter and weight- but I think that's different than what he means. 

3. 
   Rich14 | Dec 20, 2006 10:25pm | #5

   I remember reading Tage Frid's article in FWW describing this a (very) long time ago (late 70s ?) and cringing as I read it. I think if anyone else had recommended it, I would have dismissed it as the ramblings of a madman. But Tage? That kindly, grandfatherly-looking, source of rock-solid, practical advice? If he said to do it, by God, I would!

   I chucked up a cup grinder in my little Craftsman router (the kind where the whole router motor turns in the outer barrel and moves up or down as the result of the helical groove in the barrel) and moved menacingly toward my 4" Delta jointer.

   I realized that I had to devise a way to: 1. index the cutter head so that the bevels of the blades could each be brought exactly into position, and 2. lock the cutter head at those 3 positions.

   I eventually devised a wood clamping jaw to grab the cutter head shaft pulley and felt sure enough about indexing the head. Tage said I first had to "joint" the knives - grind their pointed edges at TDC position to make them all the same height above the cutter head. I seem to remember some advice also about microbeveling the knives after grinding the bevel. (gulp)

   I mounted the router on a long auxilliary base that was to sit on either the infeed or outfeed table (can't remember). Turned on the router and tried to adjust it down toward the first blade offered up for treatment. Somehow I never could bring myself to make the cup grinder actually touch the waiting steel.

   I wore no safety goggles (Tage didn't either!) What did we know then?

   It's just as well. It probably would have been utter disaster. I've always just sent my knives out for sharpening. It's amazing how well, and inexpensively a sharpening pro does the job with the proper equipment.

   Rich

1. 
   Dan1120 | Dec 20, 2006 10:37pm | #6

   I was cringing just waiting for you to say "the grinder exploded as soon as it touched the planer blade." Alas, the punch line never came.

1. 
   Rich14 | Dec 20, 2006 11:00pm | #7

   "the grinder exploded as soon as it touched the planer blade"

   In my nightmares it does.

   I'm just a wimp.

2. 
   teryg | Dec 27, 2006 08:52pm | #22

   Dan -
   When I was a kid (late 1950's) a grinding wheel incident at a neighbor's garage killed an older fellow who was standing nearby. A bench grinder wheel had been mounted on an arbor that was then tightened into a router collet. The idea apparently was to use it to grind a welded seam. When the spinning wheel first touched the weld, the wheel shattered. A large chunk of the wheel struck him near an eye. It took a huge piece of his skull and brain nearly off, when it hit. Amazing that the wheel withstood the thousands of RPMs that it did, while revving up to 'router' speed. The energy that was added to that wheel with those RPMs must have been immense. I too, read the other postings with dread and apprehension, as my own childhood memories vividly came to mind.

2. 
   RickL | Dec 20, 2006 11:30pm | #10

   Haven't read Frids description in many years but Leonard Lees is pretty detailed on indexing and such. Personally I think it's better sending them and and I can change them a lot quicker than setting up sharpening on the machine. I can change 4 knives on a 20" jointer in a leisurely 1/2 hour. I'd don't believe his doing the cutters with a cup wheel will be as good as my sharpener can do. They use a water cooled machine and can sharpen up to 120" long. They do paper knives on it as well. For planer blades they just line them up on the magnetic chuck.

   Another issue is you need to keep the blades balanced weight wise. We have a gram scale to check the knives on our moulder.Much higher speeds, 6,000 rpm, so a bit out of balance is very noticable.

   I had to sharpen the old style segmented cutters on Oliver jointers on the machine. They had a special grinder designed for this. Talk about fussy. If you didn't do it just right you got lines from the seperate cutters. The early version by 20 years or so of todays insert tooling.

1. 
   Rich14 | Dec 20, 2006 11:52pm | #11

   A large, sharpened (polished) paper cutting (guillotine) knife. Now there is one serious cutting implement. I have operated many a paper cutter. there is nothing like the sound of that blade coming down through a ream or 2 (500-1000) of full size sheets (20x26). It sounds like silk ripping.

   Both hands on the control handles. Nothing near the hydraulic clamp or the blade!

1. 
   paretsky | Dec 23, 2006 10:43am | #18

   >> A large, sharpened (polished) paper cutting (guillotine) knife. Now
   >> there is one serious cutting implement. I have operated many a paper
   >> cutter. there is nothing like the sound of that blade coming down
   >> through a ream or 2 (500-1000) of full size sheets (20x26). It
   >> sounds like silk ripping.And then some yahoo leaves a metal ruler under the blade when cutting, and you in less time than it takes to say "What the #### were you thinking" the blade is shot. Between paper cutters, hollow drill bits and presses with the safety interlocks disabled/removed, I've seen more stupid and dangerous things done in print shops than just about anywhere else."Light the lamp, not the rat! Light the lamp, not the rat!!"
   Rizzo the Rat, A Muppet Christmas Carol

2. 
   Rich14 | Dec 23, 2006 06:19pm | #19

   Yeah, The single most important thing a pressman has to learn is to put his pica stick back in his pant loop after he takes a measurement. NEVER put it down ANYwhere. I've never seen a metal pica stick get in a paper cutter, but there were all kinds of ways to dull that blade. We had an absolute rule that we never accepted a job where the customer supplied his own paper, unless it was delivered to us straight from the paper warehouse. Customers always wanted us to print on a ream of something they had been carrying around, unpackaged, on the floor of their car for a year. A print shop will cut that kind of grit-containing junk just once before adopting the "No Customer's Paper" rule. Rich

3. 
   KeithNewton | Dec 21, 2006 06:10am | #12

   If you are going to take the knives out and sharpen them yourself, I would forget the drill-press idea, and just go with a straight wheel on the table-saw. Set up a fence across the front like you would make cove, with a Kool-mist sprayer. T

   the sharpenss angle is easy to set, it is just the height adjustment, and then set the fence back for the blade width.

   However, I hone my knives on both my 12" jointer and 24" planer 4 - 5 times between grinding with 2 x 6" diamond hones.

1. 
   boater | Dec 21, 2006 05:39pm | #13

    Thanks to all who took the time to reply to my question. KeithNewton, your method of useing the tablesaw should work for me. What type of wheel do you use? I use a soft white wheel for chisels & plane irons.

   To those who were speculating about the possible disaserous results of useing a mounted wheel in the router for grinding jointer knives in place, IT WORKS!  I did that years ago on my old 4" beaver jointer.  The stone I used was a cup  shape about 1" dia. of the type used in die grinders. Thanks again for the help!

1. 
   KeithNewton | Dec 22, 2006 08:12am | #15

   When I sharpen on the TS, I like to use a 1/2" or less in width, white wheel with the Koolmist spray lube.. I don't recall if I mentioned that I use a piece of plexiglas with a slot in it for the wheel to bridge across the insert. Otherwise, the blade will run the risk of dip, and snag as the ends leave the TS casting onto the insert. I have a grinding attachment for my old Crescent thickness planer, but I never use it because it is too slow compared to the power and stability of the wheel on the TS. However, I would like to state again, because I never get any feedback from anyone. The best thing that I can recommend is to learn to hone them in the head with the diamond hones that you can get at any of the mail-order places. If I can hone 4 feet of knife blades in less time than I can take them out and replace them, plus, it cost me nothing. What is not to like about that? It is so easy when you get the hang of it. I guess I need to ask, because I normally don't read any of these magazines, because I just don't see anything that inspires me, but has anyone ever written an article about how to sharpen knives in the head? I know some of you guys have been lifetime subscribers, would sombody answer this question. If not, maybe I need to do an article on sharpening knives in the head. I find it to be quiet easy to do.

1. 
   philip | Dec 22, 2006 10:35pm | #16

   Keith, sharpening knives insitu is a normal trade practice and is good for keeping them sharp longer.(well it was normal where I came from).
   Write up your article- I am sure many folk would be appreciative.
   Talking of the CoolMist- a similar item has surfaced here, and it is a definite must for me- it is called Minicool and is made by Noga-same people who make de-burrers. Is the one you use made by Noga?
   Philip Marcou

1. 
   KeithNewton | Dec 23, 2006 04:31am | #17

   Hey Mook, I am not surprised to hear that you know how to sharpen that way, and have a spray mister unit. However when I ask about whether FWW had covered this, I was thinking of teaching some of the readers here that might not have ever considered it. I wasn't wanting to preach to the choir, so don't bother me if you already know how. I am kidding of course. Have a merry Christmas, or whatever.

4. 
   ptu | Dec 21, 2006 06:04pm | #14

   The cup grinder sounds like welding gear. Check out a welding supply place. Personally, I would pull the blades out and sharpen them by hand, or send them out. That wheel is pretty course, and they would need something else anyways.

5. 
   TomHigby | Dec 27, 2006 05:26am | #20

   I tried this method once and very quickly burned the jointer blade beyond repair.  obviously the stone was running way too fast.  If you do try it be very cautious.

   Tom

1. 
   RickL | Dec 27, 2006 04:22pm | #21

   I believe the stone was running at the correct speed but too heavy a pass would cause the burning. It's the same problem folks have with a bench grinder. A light touch is the key not slowing the speed down.

6. 
   QCInspector | Dec 27, 2006 11:14pm | #23

   Here is one maker of all things 'gritty'. Click on 'Industrial' and again on 'Distributor Locater' and you will be able to find a seller near you . They will advise you as to the best sizes and abrasive/bond type to use. ( I was curious and looked. There are 16 places within 20 miles of my place.)

   http://www.ind.nortonabrasives.com/home.asp

   If there is a brand of grinding wheel that you like they probably have similar sites. Best of luck with your hunt.

1. 
   boater | Dec 28, 2006 05:03am | #24

   Thank you  QCinspector for the link. There are several distributors near me, and I found several wheels of the type I am  looking for in the Norton cat. I am sure that with the help of the sales rep. I will get what I need.

   Thanks again , Boater.

7. 
   philip | Dec 28, 2006 10:25am | #25

   Here is a cup wheel of size suitable for what you have in mind.
   However I don't think it is a good idea at all to mount that in a drill press-it is just not practical. Sure, you can grind away after a fashion, but the results will be poor, and it is not safe.
   The wheel I have there is designed to run in a dedicated surface grinder or blade grinder at fairly high revs for something of that diameter, where the feed can be controlled , and there is a proper guard, not to mention coolant liquid.
   Far better to take your knives to professionals who have the right equipment.

   Philip Marcou