I have no idea, but found this. Makes sense, I guess...
http://www.jackrabbittool.com/art/splitpointbit.jpg
I have no idea, but found this. Makes sense, I guess...
http://www.jackrabbittool.com/art/splitpointbit.jpg
I have the 500 also. Bought one for myself and brother in law, on clearance at HD. Been couple years ago, but well worth it.
My understanding is that a split point will be easier to start a hole in a particular spot in metal. After you sharpen it, you put it in another port and it grinds the sides of the point. I don't think I would spend extra to get that if you are mainly drilling wood. One thing to consider is that if you are doing a lot of regrinding garage sale finds is to get the 100 grit grinding wheel. The DD comes with a 180 wheel standard.
Love it......simple to use and when not in use it stores away in its little bag in a cubby for another day. Split point feature is nice as well, has made many a bit I thought were garbage work quite well.
I've got one and have turned all my twist drills into split point types with it.
One huge bonus for me was being able to take regular metric bits (10mm & 7mm) and make them into split points for my lathe pen making.
Mine is the 1/2" capacity model, but more than sufficient for my needs. I very rarely ever need to drill larger holes with twist drills.
I have the 750 and wouldn't be without it. I was trying to mount a fire extinguisher in my Jeep yesterday and was using a relatively new bit to drill through the interior body metal. It just wouldn't penetrate. I pull out my Drill Doctor and after a few quick turns went back the Jeep and it instantly went through. I added the spilt point which kept the bit from wandering which in this case was important because I was also drilling through the plastic interior paneling of the vehicle.
I got a 750 a few years ago. I wanted the increased capacity for bigger bits I use on my engine lathe. It works great. Little bit of a learning curve, but once you master it, things go fine.
Dave C
I have the 750 and am glad I bought it. If you need to sharpen some large or long bits, the machine quickly pays for itself. If you havent already, buy it!
I tried one once and found the I can sharpen a bit by hand faster than the drill doctor. Personally I like sharpening them the old fashioned way.
just preferrence I guess.
Mark.
I also have the base machine and it is great. Absolutely worth the price.