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View Full Version : Alternate to a Drill Doc?



rws
01-02-2007, 11:21 AM
Just kinda thinking here...what if you were to take an air pencil die grinder with a wheel stone. Then, mount it in a tool holder, set the compound to the lathe at the proper angle, and set the grinder just below center. Hold the bit in the chuck, and you could feed the grinder down the cutting egde with the compound, turn the chuck to the other side and do it again. Once the edge is done, you could hand grind the remaining relief needed. Is this crazy?

Swarf&Sparks
01-02-2007, 11:44 AM
Not crazy, but do you really want all that abrasive over your machine?

Scishopguy
01-02-2007, 12:28 PM
S and S,

Is that any worse than using the Dumore to grind in a center? We used to cover the ways with rags when grinding on the lathe.

As for the drill doctor, I like mine and it performs well. I guess they are not manufactured consistently as folks seem to have a lot of trouble getting them to work. I think the key is a gentle touch in mounting the drill in the collet and especially when using the fixture to align the flutes. After all, they are mostly plastic.

Swarf&Sparks
01-02-2007, 12:33 PM
To each his own, Scishop.
Fair call, but I choose to keep abrasive away from my lathe.
Just pointing out the possible dangers to a machine.

Your Old Dog
01-02-2007, 12:37 PM
You might be able to sharpen them this way but I'll do 20 with the drill doctor for every one you can get done on the lathe.

I think the Drill Doctors shortcoming is that the index mark used to align the chuck in the alignment side does not look like an alignment mark. It looks more like a rib to re-enforce the chuck for strength. Had they put white paint on it like the white dots then it would have been far more obvious. The drawings in the instruction booklet are not clear enough, at least for me they aren't.

Swarf&Sparks
01-02-2007, 12:43 PM
Some good info here (which I think was first linked from this board, but quicker to find my bookmark)
http://www.gadgetbuilder.com/DrillSharp.html#Four%20Facet

Milacron of PM
01-02-2007, 01:33 PM
Best alternative is just to buy a proper drill grinder used. Like an Oliver 21...pick 'em up at auctions sometimes for just a few hundred bucks. Make sure you get both V block mounts with it for full range. Other good benchtop ones include Black Diamond and Optima. Optima made in Switzerland and currently sells for $24,000 new (not a misprint), but sometimes on eBay as cheap as $1,000 with all the tooling !

http://www.oliverinstrument.com/images/21hd.GIF

Scatterplot
01-02-2007, 06:56 PM
Not to hijack the thread- but has anybody use one of these? http://cgi.ebay.com/Drill-Bit-Sharpener-Works-Great-with-Bench-Grinders_W0QQitemZ300066286600QQihZ020QQcategoryZ4 2290QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

It's like a 10 dollar mount for mounting drills for sharpening on a bench grinder.

Magic9r
01-02-2007, 07:43 PM
Scatterplot,
they work but only approximate the correct geometry,
Nick

ammcoman2
01-02-2007, 07:43 PM
Per RWS's post: How about using a 1" diam. diamond disc in the pencil grinder instead of the usual stone. Voila, no stone dust just metal.

There was an article in MEW a few issues back re doing this to sharpen endmillls. These discs are quite cheap - I bought a 6-pack for $12 recently with a plan to try it out. The author used a Dremel with the disc mounted in the flex shaft head. It's on my to-do list!!!

Geoff

zopi
01-02-2007, 08:55 PM
Has anyone built a Tinker?

Mcgyver
01-02-2007, 09:00 PM
I've not used the drill doctor, but have drooled over the expensive ones DT mentions, and that do a perfect job. sorry, I'm not spending that much money....there may not be a way to get the traditional shape of a drill point without spending mucho $$$$ dollars but if you look at the 4 or even 6 facet point, which many believe is superior, there are more options.

I set out to design my own, and here's what I figured a drill sharpener has to do.

- needs a grinding wheel on a reasonably good spindle.
- motion to bring the work into the wheel
- need to set point angle and relief angle, a compound angle.
- needs to be adjustable for both a primary and secondary relief, possible even an addition facet, taking of the corners.
- need to be able to index 180 while maintaining longitudinal position
- needs to fit a wide range of drill sizes
- needs some sort of delicate radial adjust, ie tooth rest to the frustration out of initial set up.

I've got grinders, so it was logical to make use of one of their spindles. if you were starting from scratch, it would make more sense imo to pick up a used surface grinder or t&c grinder and make something like i did before i'd spend thousands on a drill sharpener. the exception would be if it was for business, the drill sharpener would be faster. mine will however perfectly sharpen a drill bit that'll cut a hole to within a thou or two.

I've posted this here before....what i came up with is http://bbs.homeshopmachinist.net/showthread.php?t=15226&highlight=mcgyver+grinder

the universal vice it sites on is something i built and is also detailed in a thread herein. or buy one on ebay.

if you wanted to lower the cost further, a bench grinder with a cup wheel and some linear bearings might work, but imo by the time you bought all that stuff you'd still have an inferior spindle, buying a grinder also gives a very useful tool beyond drill sharpening.

I know many (most) won't want to go this far, but if you want first class points on the drills I thought long and hard about and figured this was the lowest cost route to get there.

Milacron of PM
01-02-2007, 09:35 PM
I've not used the drill doctor, but have drooled over the expensive ones DT mentions, and that do a perfect job. sorry, I'm not spending that much money I've got grinders, so it was logical to make use of one of their spindles. if you were starting from scratch, it would make more sense imo to pick up a used surface grinder or t&c grinder and make something like i did before i'd spend thousands on a drill sharpener. Hundreds, not thousands. I've actually seen perfectly nice Oliver 21's sell as cheap as $75 at live auctions, but said "a few hundred" just to be conservative as $200 or so is more typical. $200 for a precision machine that cost many thousands new, built to be accurate for a lifetime, vs $160 or so for one of those POS drill doctors...a no brainer.

Nice Black Diamond drill grinders often sell in the $500 range with full set of collets...real nice late ones, maybe $900. Same deal as the Oliver...a tool for a lifetime, meant to do the job to industry standards.

GadgetBuilder
01-02-2007, 09:52 PM
Has anyone built a Tinker?


I have -- the Tinker doesn't sharpen drills unless you build a drill sharpening attachment for it. The Tinker's movements and angles aren't really suitable for drill sharpening.

I wound up building several gadgets devoted to drill sharpening to handle most of my drill sharpening needs, but still haven't addressed drills larger than 1/2" adequately. In my little home shop I couldn't justify an expensive grinder devoted to drill sharpening so I built hand powered sharpeners for small and medium drills and use an el-cheapo sharpener on the bench grinder for larger drills, then add a facet on a hand sharpener. As usual, if I count my time at more the $1/hr I probably should have bought a grinder... but I learned a lot building the sharpeners :D

It took me quite a while to digest the info in this short article:
http://www.mmsonline.com/articles/068901.html

I use Secondary Point Angles SPA's on many drills over #10 now and like them a lot. I haven't seen drills for sale with SPA's.

lane
01-02-2007, 10:40 PM
No I aint even going here. On 2nd thought I will . For 3/4 down t0 1/16 a Darex m5 is the way to go if you can`t afford a Black Diamond In a hurt a Lisle 91000 will do for drills 1/8 - 1 1/8 for small stuff # 80 to 1/5 a SRDworks good but is high dollar .But then again any thing is better than nothing.And with all of the above I still grind 99% of mine by hand. LEARN HOW. That is the cheepest way out. It will never be perfect but a hole is a hole most of the time . If it needs to be any thing more Ream or bore it . No such thing as a precision drilled hole. NO machine that true no drill will drill a perfect hole not even a Jig Borer for precision you ream or bore for location and size .

Scatterplot
01-02-2007, 10:58 PM
So where do we learn how to grind drills by hand? I'll admit it lol, I would suck with hand grinding anything :)

And what is a "Tinker"? A google search on 'tinker' will probably not yield a good result for what I'm looking for :D

mochinist
01-02-2007, 11:06 PM
So where do we learn how to grind drills by hand? I'll admit it lol, I would suck with hand grinding anything :)

And what is a "Tinker"? A google search on 'tinker' will probably not yield a good result for what I'm looking for :DThere is alot in this forum and most likely a lot in the PM site about hand grinding a drill bit. Do a search and if you cant find anything start a thread and ask. You would be surprised at how easy, well not easy but how well it can be done with just a little practice.

Also if there is any smaller type machine shops in your area and you're not to shy to ask, go by one, if they aren't a total CNC outfit there will more than likely be atleast one machinist that can show you how. Most machinist I know would enjoy a twelve pack of their favorite brew for the few minutes it would take to show you the basics.

J Tiers
01-02-2007, 11:06 PM
So where do we learn how to grind drills by hand? I'll admit it lol, I would suck with hand grinding anything :)

And what is a "Tinker"? A google search on 'tinker' will probably not yield a good result for what I'm looking for :D

Hand grinding is well discussed in some posts by Forrest Addy.... And, I think, in a magazine article in our own host's mag, I think..... You could check the article index........

T'aint hard to get it creditable, but the old hands will laugh at your results..... nemmind them, if they drill holes where you want and within a few thou of correct size, they are "right".... drills ain't precision anyway.

Gotta look at McGyvers on a wider bandwidth line..... .

If D sees this, how much do those nice $75 drill grinders weigh? I don't get a feel for size from the picture..... I'm thinking about an 18" cube of machine...... in the 200 -300 lb range......

And, don't most of those need 8 jillion collets? That one looks like it may use only a few jaw sets, but the B-D takes a collet per size IIRC.... and isn't worth much without them....... so if you get the machine you also need a couple hundredweight of collets.

dp
01-02-2007, 11:09 PM
The Tinker info is found here: http://lautard.com/tinker-s.htm

You can learn a few things here: http://www.manufacturingcenter.com/online_book/

and here: http://www.steeluniversity.org/content/html/eng/default.asp?catid=1&pageid=1016899460

and here: http://jjjtrain.kanabco.com/vms/cutting_tools_drill/cutting_tools_drill_00.html

Milacron of PM
01-03-2007, 01:11 AM
If D sees this, how much do those nice $75 drill grinders weigh? I don't get a feel for size from the picture..... I'm thinking about an 18" cube of machine...... in the 200 -300 lb range......

And, don't most of those need 8 jillion collets? That one looks like it may use only a few jaw sets, but the B-D takes a collet per size IIRC.... and isn't worth much without them....... so if you get the machine you also need a couple hundredweight of collets. Oliver 21 weighs about 175 lbs I think. Black Diamond maybe 100 lbs.

Oliver only needs the two V blocks as shown to cover the full range up to 1/2 inch. Black Diamond needs a gazillion collets but they almost always come with all the collets...since the collets are no good for anything but the BD, most folks keep up with them ok..maybe a few get lost, but most are there ususally. Collets are tiny little things...whole collection of them up to 3/4 capacity probably only weigh 30 lbs and fit in one drawer.

A.K. Boomer
01-03-2007, 01:12 AM
So you blokes got me thinking with all this talk of precision on the drill bits and stuff, i can see the really good machines covering all the things that need to be done except one, what gets the proper degree on the bit itself --- not the angle (118 or whatever) im talking about something even more critical, what part of the drill do you rotate to and start grinding on? is that still just eyeballed??? go for the main material mass? sounds kinda crude to me, a little fore --- a little aft and you drastically change your relief angle --- now im no machinist but it dont take me no abacus to figure out that thats a fuqe...?

Mcgyver
01-03-2007, 01:11 PM
So you blokes got me thinking with all this talk of precision on the drill bits and stuff, i can see the really good machines covering all the things that need to be done except one, what gets the proper degree on the bit itself --- not the angle (118 or whatever) I'm talking about something even more critical, what part of the drill do you rotate to and start grinding on? is that still just eyeballed??? go for the main material mass? sounds kinda crude to me, a little fore --- a little aft and you drastically change your relief angle --- now I'm no machinist but it dont take me no abacus to figure out that thats a fuqe...?

AK, more critical than how its indexed to start, is that both sides are the same. its actually pretty easy to line up the starting point by eye. I just eyeball the lip to be a little past vertical so i get a fair rectangular shaped facet making up the primary relief. not sure what you mean by for and aft - the position of the drill along its length has to be accurately controlled, its the radial position of the lips at the start that is manually set, at least on mine, can't speak for drill sharpeners at large

Precision is an ambiguous word, what's precision? my objective is a hole within a couple of thou and a drill that cuts well, and cuts straight (minimal wander). this requires a well sharpened bit. as was pointed out a reamer will get you to the finished size if you need better than a couple of thou accuracy, but it will not relocate or fully straighten a hole.

I can sharpen by hand and its good to know how, but my jig sharpened drills cut better and more accurately. maybe a pro with all the extra practice they'd get can do as well, but doesn't seem logical - there;s limits on how well you can eyeball the length of the lips.

TGTool
01-03-2007, 01:35 PM
I worked for a guy one time who sharpened end mills on the bench grinder. Yeah, he did have a good eye, but I think he was kidding himself about doing a good job. Funny thing was, he had a surface grinder and a fixture for holding end mills to do the clearance and relief angles that he never used. The other guy in the shop who had worked there quite a while said he thought the boss didn't understand how to use the fixture so ignored it - and wouldn't let the other guys use it either. I finally just walked from that job.

seatlanta
01-03-2007, 03:05 PM
I received a Drill Doctor as a gift several years ago, and I've used it regularly since then.

It's easy to use, and I've been quite happy with it. I was surprised at how well it restored my dull and damaged drill bits.

I have some trouble aligning smaller bits--3/16" and below--but overall, it's a great machine. I recommend it.

James (seatlanta)

Alistair Hosie
01-03-2007, 04:21 PM
I have an industrial jones and shipman cost me about 100 including cost of gas to collect it much less than a drill doctor which is highly overpriced and rated in my opinion see for your self Alistair.



http://img.photobucket.com/albums/0903/tybachdai/DRILLPOINTTOOLGRINDER026.jpg

IOWOLF
02-16-2008, 11:26 AM
I cant believe I missed this the first time around, I have the Oliver mentioned, though older. Correct about #175 on stand and I got mine for $40.00 or so at an auction,With extra wheel but no small bit holder,They are still in business so I called and they only want $300.00 for the small bit holder,So I bought a Drill Dr. for $70. and do the small ones on that.

I can Do split point bits on the Oliver and I'm told drill like new or better.

http://img.photobucket.com/albums/v11/iowolf/oliver.jpg