[hrjme]

I rarely have broken a drill bit over 1/8 inch. I would assume broken bits are the result of a combination of abuse during a machining operation. A dull or improperly sharpened bit will cause frustration and rage that in some may aggravate the situation.

If the chips are not pouring out of the drill hole, then you should not try to force it. Look at one of those "new" bits, and examine all the angles and edges involved. If the bit does not look like new, then do not use it.

I use to sharpen bits by hand on a grinder with good results, using the method my step dad showed me. A number of years ago, I broke down and bought the 3/4 inch capacity Drill Doctor machine on a tool catalog sale. Once I got use to the setup, I use it all the time. (READ the INSTRUCTIONS. If the back (cutting) angle does not look like a new bit, your setup was not correct.)

About Bits. I like American Vermont. But, for normal drilling of mild steel, make sure you are using bits marked as HS or High Speed Steel. If you are drilling something hard, such as grade 8 bolts, some frame steel. Channel from old bed frames, etc, you will need tougher bits. Carbide or carbide tipped are best. I actually fabricate things out of old leaf springs. I use the carbide tip masonry bits to punch holes. (You can also use them to drill holes in bottles for making lamps, etc) I do not waste money on coated bits. Once the coating is gone, you are sharpening the base metal. Oh yes, the Drill Doctor can grind a special angle at the web (center) of the bit, that makes starting holes in the right spot easy.

Summary: Know what you are drilling, chose the right bit for the material, keep the bit sharp, and if it seems you are not getting anywhere, step back and figure out what is wrong.

[66GMC]

I'd like to know if those "Drill Doctor" (TM) units are really worth the money or not.

I bought a $50.00 sharpener from Princess Auto here in Canada ... and I'm less than impressed. Off-shore junk ... I guess you get what you pay for.

[Irelands child]

Originally Posted by 66GMC

I'd like to know if those "Drill Doctor" (TM) units are really worth the money or not.

I bought a $50.00 sharpener from Princess Auto here in Canada ... and I'm less than impressed. Off-shore junk ... I guess you get what you pay for.

In a single word YES, the Drill Doctor is well worth the bucks

But of course, I can't say anything with a single word. I've had a drill doctor for probably 5 years and with the exception of replacing a broken smaller size drill bit, not replaced any due to being dull. I've resharpened a couple of hundred that I had in my tool box that were too dull. Some drill bits because of the degree of twist occasionally need some thought to get the heel in a negative angle, but that's something you work out. They do suggest cutting back the point, but that's one of those things that really is unnecessary.- mine has only the capacity through .500 as I didn't feel I would use anything larger - and saved a few dollars - you can buy the adapter later if needed.

Dave W

[timothale]

The best drill bits I have found were at a flea market in Calif when I was to the coast to visit the kids. The seller said he bought them from a surplus sale at Boeing aircraft in Washington. They are longer than normal and all sizes have about a 1 inch long 3/8 shank with dimples. probably for a cnc machine chuck. The larger sizes have a 2 step cutting edges like on a uni bit. They are brittle and I have snapped a couple. they were 3 for a buck for the smaller size bin and 2 for a buck for the larger ones. When we go down again I'll try to get as many as I can.

[timothale]

I have an old $ 15 general sharpener I use for larger size bits that won't fit the drill doctor. It works with a regular grinding wheel and only sharpens one side at a time. It takes some care to get both sides of the bit the same. I built a 5 K sq ft 16 ft high wall metal building and I used the drill doctor to keep the Iron Workers in sharp bits and they said they went a lot faster than they normally did on their other jobs.

[hrjme]

The stepped drills are a combination bit, used for drilling a hole and a seat in one operation. They are possibly meant to be used with hex socket head screws, recessed below the machine surface. The smaller diameter is probably a clearance diameter for the shank of a screw, however, unless marked as to size, you may need to use a mike and screw size chart to figure out if they are metric or SAE.

There are better drill sharpener machines on the market than Drill Doctor, but at costs 5 to 10 times higher. As I said, I hand sharpened my dills for years. but I would not be without my Drill Doctor now. Get the 3/4 capacity model. Drilling oversize holes for clearance makes assembly a lot easier, so if you only expect to use 1/2 inch botlts max, you should be able to sharpen a 9/16 bit. Larger bits can be found at surplus stores, and flea marts.

The shank on drill bits are usually softer than the bit. So if you buy some over size bits, even tapered bits, and you can find some one with a machine lathe, the shanks can easly be machined down to smaller size, such as 1/2 inch. You might even find a machine shop class at a local school that could do this as a student project.

JME

[ogre]

drill doctor is worth the money, if: you have a lot of quality bits to sharpen.
once your bits are sharp again, you rarely use it.
if you have cheap bits, you'll wear out the stone on the drill dr
if your dulling quality bits a lot, your doing something wrong.
drill doctor is one of those tools that a couple of people can go in together on.
my neighbor & i share one, i haven't used it in 3 yrs

[deadbodyman]

Drill doctor... If your wearing out your bits,the most common cause is not oiling them ...keep them lubed while drilling with cutting oil and they'll last. I have boxes of bits I resharpen, the only ones I buy are the double ended 1/8"bits when they break.I figured the drill doctor has paid for itself 5 times over in the two years I've had it ...Easily....

[Irelands child]

I just drilled some seat tracks that had to be made out of about the toughest steel I have ever drilled. Dragged out the Drill Doctor after rounding off a couple of drill bits, resharpened the 13/64 then punched right through . Now, off to do the 3-4 that were not quite sharp enough ( they were dull from use - my bad!!)

Dave W

[scrot]

To sum it up, it sounds like the original poster's problem was that he wasn't using cutting oil on the bits.

[deadbodyman]

also drilling through rusty steel will kill a bit quick..One other thing I've found to save your bits is drilling a small 1/8" hole then going to a bigger size its a lot faster and keeps your bigger bits in good shape longer...especially when working with rusty steel...

[ogre]

yes, do like DBM suggests, use a pilot bit for anything over 1/4".
it saves on your bigger, more expensive bits
the drill dr doesn't work on bits under 3/16", so buy a couple of those to toss away
cutting fluid will save your bits

[hrjme]

I usually drill holes dry, since I can sharpen bits when required. And whenever possible, I use a drill press with a low profile vice to hold the object. However, I sometimes use a lubricant. I now use Water Soluble Oil. It makes a big difference, especially in tapping holes, of which I do while the piece is still in the drill press. This keeps the tap aligned with the hole, a problem when trying to start a thread by hand. I found that I could power the tap through deeper using the fluid. And, of course, it helps with drilling, using larger bits. (See my remarks about cutting down shanks of big drills to fit my drill press and drill chucks.) I get my water soluble cutting and tapping oil from the local Napa auto parts, Sta-lube brand Soluble Oil. It goes a long ways, mixture is recommended to be 10 to 30 to one for machining. I put the diluted solution in a spray bottle, liberated from the wife's cleaning supply cabinet.

More drilling tips. Drilling up through the bottom of a vehicle frame? Set up a hydraulic jack to feed the drill through the frame. Works slick, and helps control the feed when the bit goes through the frame, without as much chance of the bit jamming as it goes through. When drilling through the side of the frame, take a piece of a shovel handle, bolt a light chain near the end. Wrap the chain around the frame, and put the wood through the loop handle (if so equipped.) This gives you the leverage and control to easily drill through with out so much strain on you. And, when you cut through, gives you leverage to keep the drill motor from trying to wrap you around it. I also use an on-off-coast motion on the power switch as it nears break through. If it does jam up, without power on, it will take the pressure off the bit and you. I also use a very light finger touch on the switch, ready to get off it quick.

And do not forget the spade carbide masonry bits for that tough steel. My drill doctor will sharpen these too. I usually touch up a new one, just to make sure the angles are right. Using a drill press, sharp bits, and accessories like the above will help you reduce breakage and drill abuse.

JME

[Irelands child]

After my last post, I dragged the Drill Doctor to a comfy seat and touched up my small box of bits - in about 15 minutes. A couple were chipped - fixed 'em right up. That's enough of them for this sitting, but have my big box of letter, number and fractionals to do plus probably a hundred of oldies - someday

Dave W

[ExcessiveRodder]

Just picked up a Drill Doctor today. All I can say is well worth the money.
As we all know the larger bits can be quite expensive. Tried using a 1/2 bit out of my box and it would barely cut at all. After the Drill Doctor it zipped right through.

Made fabbing my front leaf spring mount much easier and less frustrating. No Ubolts for me