What abrasive wheels for lathe bit grinding

Iggy,

1/3 Hp is fine.. this is all about finesse not brute strength...

HSS or cobalt, grind on any wheel you have...

Carbide, "green wheel", best done with a water drip too.

Truely... toss all that stuff and get some T*** holders, you'll be happy you did.

--.- Dave

try 60 grit I hardness aluminum oxide for steel and about the same grit and hardness in silicon carbide for tungstun carbide you might be able to bum some half worn wheels off someone with a surface grinder for coffee and donuts

It is enough.

Green wheels will grind carbide but I sure don't like the looks of result. A diamond wheel is SOOOO much better. DO NOT USE FOR STEEL.

Steel, aluminum oxide. I tried to grind HSS using the green wheels on my Harbor Fright tool grinder, sloooow.

The way you shop auctions, I expect to see you with a baldor tool grinder you got for a song.

Sure wish Harrold would come back to the group.

Wes

-- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller

HSS lathe tooling you can grind with almost any wheel. Carbid tooling requires a green wheel for roughing and a diamond wheel to finish the edge. If you don't finish the edge your surface finishes will be rougher than they would be with a diamond finished tool. You can also get a diamond file to finish the edge. On some HSS tooling for special jobs I use a dremel grinder since I have more control with it.

A 1/3 hp motor is plenty for tool grinding.

John

Dave, I actually followed your advice and bought a BXA style holder from Enco. It arrived a few days ago.

Today, I machined the supplied oversize "nut" to fit into the slot on my lathe. Everything fits very well. The holder seems to be extremelly well thought out and seems to work great so far.

I am very happy and want to thank you. I have a few lathe bits that fit, hss and carbide ended, but a lot of them need regrinding.

Also, I have a lot of 3/4" lathe tooling, all brand name (kennametal and carboloy), and it does not fit the BXA holder. I think that I will mill that stuff down to 5/8" square.

i

Wes, I come across baldor tool grinders all the time and sold a few already. Another one will come up one day. That all should not be a problem. For now, I will mount a diamond wheel on a regular bench grinder, it will save some space and should be OK.

But here's where I am confused: a lot of lathe bits with carbide ends, have carbide brazed to steel shanks. Can I grind that with a diamond grinder or not? Steel will definitely be ground along with carbide.

John, thanks. I think that I will set up a dedicated grinder for lathe bits. 1/3 HP. One wheel will be green and another, diamond.

You do not want the HSS blank to be ground on the diamond wheel. the way I have always done it with brazed carbide tooling is to rough grind the HSS relief then rough grind the carbide to the approximate shape putting enough relief on the carbid to be able to finish only the top half of the edge of the carbide without touching the HSS with the diamond wheel. Remember not to heat the carbide up too much or the braze will melt. Same goes for when you are cutting.

John

For anyone that hasn't read the hundreds(?) of worthwhile past discussions concerning abrasives for sharpening cutting tools, consider yourself cheated by your own neglect.

Harold V and others have given all the advice that any HSM would likely ever need to know, on the subject of sharpening, resharpening or grinding of cutting tools (and the proper use and care of abrasive wheels).

But how could one ever find that info now, I wonder.

Goog Advanced Search

Anyone who chooses not to read the real metalworking threads in this NG is wasting opportunity.

I suspect that every news reader has a feature to save messages, and this would be an excellent way to build a reference library of useful information, but only if one chooses to use that feature.

WB ......... metalworking projects

He may still be lurking. Our ISP has a broken usenet feed and when he posts I'm about the only one who can see them. (I'm posting through another server)

[ ... ]

I've done this (3/4" to 5/8"), and I have one significant suggestion:

Mill off the *bottom* of the shank, not the top. The height of the cutting tip of an index is about level with the top of the shank, and if you mill off the top of the shank the cutting tip may not lower enough to match the center height of the lathe. There is a limit to the adjustment range on a quick-change toolpost.

I used a wide conventional milling cutter in a horizontal mill, not the end of a vertical, which may burn on the rather tough steel of the shank if you aren't careful.

Good Luck, DoN.

OK. I think that it should not be a problem with carbide end mills.

These quick change toolposts are a great invention.

Don't toss it! I love the insert-type tool i use, but occasionally I want a really smooth surface on Aluminum, a special shape, or need different relief angles for copper or plastics.

If you have both white and green or diamond rocks mounted why not grind as much steel out of the way that you can with the white rock and then grind the carbide with the green rock or diamond. Unless you really over run the tool you should be able to get several "touch ups" on the carbide before you have to grind more iron. A belt sander with AlOx belt will work well to remove the excess steel under the carbide insert.

Good tip in "Machine Shop Trade Secrets" is to use a left tool as a right and a right tool for as a left by rotating 90 degrees. I have not used this much but it seems to work well giving extra support to the carbide.

Unka' George [George McDuffee]

------------------------------------------- He that will not apply new remedies, must expect new evils: for Time is the greatest innovator: and if Time, of course, alter things to the worse, and wisdom and counsel shall not alter them to the better, what shall be the end?

Francis Bacon (1561-1626), English philosopher, essayist, statesman. Essays, "Of Innovations" (1597-1625).

Iggy,

Check to make sure the shank isn't hardened...

Long ago before I bought any holders, I was given a 3/4, which was WAY too big for my old import lathe.. I was gonna "mill" it down but before I tried ,I took a file to it.... skipped like a stone on water... shank was hardened..

I had a friend that had a tool post grinder and he "spun and ground" it for me...

--.- Dave

Update: Harold is still lurking and Wes should check his mail.

How much does Giganews charge?

Newsguy charges (among other prices) $9.95/Month for a download limit of 9GB/Month (back when I joined -- it keeps growing over time, and I naver get close to the download limit so it keeps accumulating). Or , you can go $99.50 per year (so you get two months free by the monthly pricing) -- or there are various other ones with other limits if you need more.

Enjoy, DoN.

This is from Harold via my anti spam account. I don't check it often but saw it today.

I am unable to post to RCM, thanks to my moronic ISP, who doesn't get the picture that, somehow, posts that appear on their server are not being forwarded to the news group. No amount of complaining, not only by me, but by others, has made any difference to them. Things went south about March of this year and have not improved. I still read when I have time, but not on a regular basis.

These guys desperately need to read some information on tool grinding. All too much BS is being promoted.

Some time ago I posted (on the Chaski board) several threads revolving around grinding HSS, chip breakers, wheel selections and grinders in general. The posts were very extensive----and contain information that could benefit even seasoned machinists.

I was contacted by a party that suggested I post them in a common place for others to download. Not wanting to appear as a know-it-all----I suggested that it likely wouldn't appear to be the wise thing to do, but if he wanted to do it, he had my permission. I don't consider anything I'm willing to post as being anything worthy of protection, and it should be available for anyone that has confidence in my opinion. As a result, he compiled all of the posts, which are now available for download free of charge.

I'm going to provide links to the Chaski board that lead to the three threads, and I'll also provide the link that leads to the compiled posts for those that might want to download everything as a unit. Feel free to post the information on RCM---or even to copy this and post it directly if you feel it's worthwhile to do so.

?t=75969

regards,Harold

-- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller

Harold, that last link 404'd on me.