[How do I?] Any tips for using the Drill Doctor x750?

HMF

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Well, I ordered a Drill Doctor X750 from Enco with the 15% off and web sale last Friday.

Now I need some tips on using it to produce good, sharp drills.

Can those of you who own one, please, give me some tips for good operation?

Thanks!



:tiphat:Nelson
 
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For me, same as Edk says. I wait until I have several to resharpen. Seems like even after watching the video and reading the manual, I still need to do a couple before I get the feel of things. Then I have to go back and redo those first couple.

Bill
 
The instructions are pretty good that comes with it. Just be smooth and even on each side when you grind and you should have no problems. I sharpened bits I have saved for years. It is pretty fast once you get the hang of it.



be
 
I'll add another vote for "Watch the video" and "not been able to get the split point to work".

At least for me the "secret" is in setting up the bit in the holder properly. The key for me was letting the spring metal fingers rotate the bit to get the proper axial orientation of the bit in the holder. I will put the bit into the holder very loosely. Then put the holder and bit in to the “alignment port”. A very light pressure on the back end of the bit will push it forward until it hits the metal stop in the “alignment port”. I then look in the top of the “port” and watch as the metal spring fingers ‘grab’ the flutes of bit and rotate it into the correct position. If you are wondering what I am talking about then give the bit a little twist and watch as the spring fingers “grab” the flutes and rotate the bit back into position. I then tighten up the holder a little at a time making sure the fingers keep the bit in the correct axial position relative to the holder.

It sounds complicated but by looking in the top of the alignment port is becomes “intuitively obvious” what the fingers are trying to do. The metal stop is precisely setting the depth of the bit in the holder and the fingers are precisely defining the axial rotation of the bit with regards to the holder. So just do the best you can to help them “do their thing”, slowly tighten the holder to secure the bit, and in 30 seconds you are ready to go.

The “split point bit” operation – well I have not figured that out yet but I do know you can completely grind the end of a bit off if you are not careful.
 
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+1 on holding finger pressure (pushing the bit into the stop) on the drill shank as you tighten the chuck. When you pull the chuck out and are ready to grind, look at the chuck jaws from the rear and make sure they are not "leaning". If you over-tighten the chuck they will do that, and twist the bit out of position. Just loosen the chuck slowly until the jaws are all pointing straight into the center.
 
I have an older model Classic Drill Doctor 750 and have found that many times it doesn't make the correct clearance angle when using the lips to position the bit. This tool ahs not been abused and only lightly used so I'm certain it isn't damaged. Whether this is a defect in the sharpener or or if it has something to do with the helix angle of the bits being sharpened, I can't say. I suspect that the helix angle of the bit would affect the position of the tip and hence the relief angle since the lips grip the helix to obtain the supposed proper position. For me, a work around for has been to use the lips to position the bit, do a trial sharpening and if the clearance isn't correct rotate the bit slightly in the holder and resharpen. Usually, with my bits I need to rotate clockwise but, again, depending on the helix, counter clockwise may also be necessary.

Perhaps the updated models have addressed this issue. I would want to know more before I purchased another as I am not completely satisfied with mine.
 
Nelson,

My views on the Drill Doctor 750 have been made very clear, so I will not repeat them here!

Get in some practice using your Baldor 500 and a few bits and before long, you will be able to sharpen better and faster freehabd that you will ever do with that.

Walter
 
all my drill bits i do by hand and eye and gage[the way the military course taught us] it never fails]:biggrin:
 
Thank you everyone, for the advice.
I have printed out your replies for reference.

The DD X750 arrived yesterday evening.
I am going to watch the CD and see if I "get it".

I am also going to start on getting my 1960 vintage Baldor 500 working, but that will take time.

Meantime, I won those 500 drills on Ebay, and some need sharpening, and I can practice on them.


Walter- the Baldor 500 is 3 phase. I have an older Teco VFD someone gave me and will need to clean up the motor,
check the bearings, and figure out how to wire the VFD to it using the old control box (on-off-reverse).
I'm going to start another thread on doing that.


Nelson
 
Nelson,

Aa the owner of the DD 750X, I can state that it CAN give good grinds, and CAN split points properly. However, both take some finesse and practice.

My first advice to you would be to avoid split points until you get the hang of sharpening standard 118 degree point bits. When you master this, and understand the geometry, I can discuss how to get split points to work right in a way that will make sense in text. It doesn't work well the way the say to do it and usually results in a bit that's cut away way too much. Also, my DD needed to have the axial position of the wheel on the shaft tweaked slightly to get good splits.

In any case, you'll probably have to finnagle the lock nut and the retaining spring on the diamond wheel to get vibration down.

Also, the manual isn't entirely clear on setting the point angle vs the relief angle. The usey the same numbers (i.e. 118 or 135) for both whereas my understanding of drill geometry measures the included angle between the points as the point angle and the relief angle as the angle generated between the cutting edge and the trailing edge of the lips (typically 5 to 20 degrees, usually around 12). The lock screw and pivot adjustment controls the point angle, the chuck setup guide (the part with MTO adjustment) controls the relief angle.

You'll know you have the hang of sharpening (not split pointing) when you chuck up your newly sharpened bit in your drill press, drill a hole into aluminum, and it cuts like butter with a smooth sided hole. The final check is to measure hole diameter vs drill diameter. When they agree within 0.002 or so, you've mastered it! If the drill cuts oversize, your grind is not symmetrical with respect to the chisel point.

Also, the optional 100 grit coarse wheel is a valuable option for large bits and when splitting points on larger bits.

John
 
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