Drill Doctor DD500X Twist Drill Bit Sharpener - 3/32" to 1/2" - Electric Sharpener - High Speed & Portable - For Steel, Masonry, Carbide & Tin-Coated Drill Bits - Adjustable 118° or 135° Angle

I have used several bit sharpener in the past and gave up on them very fast. The Drill Doctor 500x is perfect I can't believe how easy it is to get dull bit to be like new. l will recommend this tool to all my retired friends.

After reading the instruction booklet I found the on line video to be very helpful. I found it easy to operate and the performance was great

I bought this machine a few months ago. I've used it to sharpen quite a few bits, 50+ ranging from HSS to masonry. I will emphasize that you MUST read the instructions thoroughly, and watch the DVD as well. It is important to know how the tool works, and why you will ruin bits if you don't follow the instructions.To sharpen standard 118* bits couldn't be easier. This machine does an excellent job of it, and since I use most of my drill bits to drill in wood, this is the perfect angle for me. Split points can be ground on 118* bits, and I have done this with success. To sharpen masonry bits is also very easy, and the machine does an excellent job in this regard as well.Where it gets tricky, for me anyway, is in sharpening 135* split point bits. These days nearly all bits sold are this type and it's nice to be able to recreate the same angle and split point. While I have sharpened bits of this angle with success, I haven't been able to get perfect results all the time. Proper alignment is critical. Trying to adjust the relief angle seems to make proper sharpening more difficult and I would not recommend it to someone who just got his hands on this machine. The relief angle is adjusted by putting the chuck to either side of the 118* alignment slot (the + and - increase and decrease the angle). This is to allow a more aggressive or less aggressive cut. Fiddling with this adjustment seems to throw off the split point when it is being ground as well, taking off way too much material. If too much material is removed during the split point procedure, subsequent sharpening of the bit will not yield the same angle since the alignment fingers will not hold the bit from is flutes, but from the newly ground area behind the split point. It is hard to visualize this, the mistake must be made to understand it fully.Changing the diamond wheel is straight forward and easily done. The machine has a somewhat loud squeal when running, but it isn't too bad. I have sharpened broken bits with success, so that feature definitely works. Also, unless a bit really damaged during a botched sharpening attempt, it can most probably be sharpened to at least a 118* point again, though it will take a while and several alignment and sharpening procedures. I recommend the 100 grit wheel for when this must be done as it will take less time, and then a follow up can be done with the standard 180 grit wheel. The 750X has more features than just being able to accommodate larger bits, so in my opinion it is definitely worth it. I wish I had gotten that model instead, and I believe sharpening 135* and split points would be easier and faster. This is a quality product though, that I must say.**EDIT 7/26/08**After using my DD extensively during a project to sharpen a masonry bit, I noticed something that I hadn't observed earlier. When sharpening the bits according to the instructions, the machine does not put opposing angles on the tip of the bit. That is, it grinds both sides of the tip to an arrow point, and this is NOT conducive to easy drilling. In fact, I realize that I put unnecessary load on my drill using the "sharpened" bit. Perhaps experimenting with bit alignment might help, but that can just as easily ruin a bit you're trying to breath more life into.**EDIT 8/3/10**I am adding an edit to this review, mostly to address other reviews and comments about people needing to read and follow the instructions. On *MY* machine, only the 118* angle is indicated on the alignment port. There is NO mention of 135* angle, and this is why I had problems with aligning and sharpening 135* split point bits. After much experimentation and frustration, I finally got the 135* angle by inserting the chuck into the "-" slot, then putting the sharpening port at 135*. I don't know if my machine had a quality control issue, or if all the DD500X units are like this. To split the point on 118* or 135* bits, you need to align the bit at 118* regardless of the angle you sharpened the bit to. In splitting the point, it must be done carefully to avoid under-splitting because if that happens, the bit will NOT cut. For 135* bits, if the point isn't split, it really won't cut unless you're drilling into a very soft material like plastic or wood.A long review for certain, and a good machine, but not without faults. After owning my machine for a couple of years and using it extensively I feel my four star review of "very good but not excellent" is fully justified.

Good

Works great, easy to set up and use.It's nice having sharp bits

I am surprised to be giving this a 5star rating, I didn't expect it to be this nice of a tool.This is an easy setup, guick to use and seems very consistent.I think a person could get to 1 bit per minute or less once all the bits have been run through so you have a consistent starting angle. I have 150 bits and so many different angles exist from years of past hand sharpening and using less exacting sharpening tools all of which need to be "corrected" to a common angle which sometimes causes you to reset the depth a couple times before the whole tip is consistent.Once there, I think a bit/min would be doable without much effort as long as the bits are just dull and not damaged requiring extra passes.I did 3 in two minutes including running them thru the point splitter after they were sharp.Overall this is a homerun for a shop or garage application where exacting tolerances aren't needed but sharp bits are.

Just received this today and very pleased with this purchase. Despite some other reviewers comments, the instruction manual is comprehensive, easy to understand and fully explains the operation of the Drill Doctor. I had no trouble setting up for 118 or 135 degree point angles.I resharpened some 34 drill bits from 3/32" to 1/2" that were blunt and changed one from 118 degrees to 135 with a split point. It took about 1 hour and 15 mins in total. After, they all were sharp, exactly to specification and cut through wood and steel like they were brand new. The 135 deg split point drill bit I cut (5/16") produced the perfect Curly Q's as shown in the photo, when cutting through a 1/4" mild steel bar with my drill press.I've always tried to hand grind my drills or bought new. While they were fairly sharp and drilled OK after my hand grinding, they certainly looked hand-ground and weren't like a new drill bit with a well-defined chisel edge, relief angle, even cutting edges and a perfect point angle. With a couple minutes work in the Drill Doctor, I have perfect bits.Points to note:- The 135 deg point angle setting is the one notch to the right of the 12 o'clock positioned 118 degree notch in the alignment port. The other 10 deg notches are to fine tune the chisel edge and relief angles, which 99 times out of a 100, you won't need to adjust.- Make sure the spring steel jaws in the alignment port snap into the drill at its narrowest point across the width of the flutes. Rotate the drill bit as required to make this happen. This ensures the correct angular position of the bit in the chuck for grinding.- After finger snugging the bit in the chuck in the alignment port, remove it and hand tighten. That way the drill doesn't move from its perfect alignment for grinding.- Keep rotating the chuck in the grinding port with light pressure down and keeping the chuck against the cam pin, grinding until the grinding sounds stop occurring. The bit at that point is fully ground.- Eventually the grinding wheel will wear down. You can remove it and turn it around to get another 100 or so drills sharpened before having to replace the wheel for about $20. After doing all my 34 drills, I could feel that the roughness of the grinding wheel was less that the other unused end, but it was still easily capable of grinding bits.- Grinding dust does spill out onto the bench through the gaps around the transparent cover under the grinding wheel. After all my bits, I had a tiny heap on the table, with more inside the machine. I cleaned the Drill Doctor before putting it away, per the instructions.- Don't mash the bit into wheel, especially for making the split point. Treat it gently and pulse it until the sound stops.I've now got a way to have sharp drill whenever I need them. I always had to make do or go buy yet another drill bit.The Drill Doctor is not a cheap tool, but it is well-made and sturdy. Once you have it, you can really appreciate its value. No regrets at all. I will never need to buy bits again until I've worm them down to an unusable length and by then, that will have paid back the cost of the Drill Doctor many times over!