Thread: Drill Bit Sharpening Station

Originally Posted by Morbius

I have been pleasantly surprised by how easy to use these old jigs are for sharpening bits, leaving my hand sharpening effort in the dust.

Craig

Yes, they are an unassuming good performer on the standard profile drill grind.

what do you use to dress the side of the wheel?

Originally Posted by havabeer69

what do you use to dress the side of the wheel?

I dress aggregate grinding wheels with diamond dressers. I have a supply of discarded diamond cutting wheels (cut up into segments) that work quite well. Also one of these...

Dresser Grinding Grinder Disc Bench Wheel Stone Diamond Dressing Tool | eBay

Don't breath in the dust that comes off the aggregate wheel when dressing it.

Be aware that some grinding wheel manufacturers warn against grinding on the sides of their wheels.

As there is only a small contact area for the sizes of drills that fit into this style of jig and more control with the jig than freehand sharpening I personally think that there is minimal risk from doing so, but obviously no risk at all.

Adding a diamond disc to the side of the wheel (as BobL on this forum has done) would eliminate that risk and give a much better edge at, say, #180 or even #240 grit. A 150mm size would allow for the 200mm grinding wheel to wear down without interference from the diamond plate on the side.

150mm 6" Diamond Coated Flat Lap Wheel Grinding Disc Jewelry Polish 80~3000 Grit | eBay

Drill out bore (from non diamond side) to fit your shaft size.

As luck has it, I trialled using a diamond dresser, as suggested below, and it worked well.

The wheel is an original GMF wheel, which was an unexpected find on a grinder of this age. In fact both of the wheels were when I received it. I replaced one last night with a wire wheel instead.

Craig

Those old drill sharpening jigs are great value for money. I had one, It was lost in a fire back in 2017I and to replace it I bought a "Drill Doctor" a few years ago and it never really lived up to it's advertising claims. It would sharpen drills but never as well so as they were near as good as new. I finally bought another from Amazon in the UK, got it set up on a cheap Ryobi 6" grinder and the "Drill Doctor is officially redundant.

This is very timely thread,
I have two 6 inch Gmf grinders and the same drill grinding jig.
Possibly similar collection of Blunt as S…. drill bits.

So very happy to hear your getting good results,
I think I will move this project up the board ladder a bit.

Cheers Matt.

If you wander around the web and look for info on a "General tool" grinder you will probably come across the instructions on how to use the little gadget. It's a little more fiddly to use than something like the "Drill Doctor" but it gives angles closer to the factory original cutting angles when you re-sharpen drill bits. The thing I bought via Amazon was sold under the "Draper" brand name from the UK and cost me around $53.00 landed in my letter box. So far it has reclaimed over $100 worth of drill bits (19mm drill bits are not cheap!) that my $500 "Drill Doctor" machine was wearing away without making them cut anywhere near as well as they would when they were new.

For what they are worth, and you need a magnifying glass to read the originals, these are copies of the original instructions for the "Draper" jig. Better than nothing if you can enlarge them.Document_20211229_0001.pdfDocument_20211229_0002.pdf

Originally Posted by Old Hilly

For what they are worth, and you need a magnifying glass to read the originals, these are copies of the original instructions for the "Draper" jig. Better than nothing if you can enlarge them.Document_20211229_0001.pdfDocument_20211229_0002.pdf

And another source...

https://images-na.ssl-images-amazon....1YvX8XRHXL.pdf

Thanks NeilS, the version on Amazon are better than the little print from the UK version.

Originally Posted by NeilS

And another source...

https://images-na.ssl-images-amazon....1YvX8XRHXL.pdf

No excuses now, just have to give it another try.
Thanks NeilS.

Originally Posted by havabeer69

what do you use to dress the side of the wheel?

I used a diamond dressing 'stick' I picked up off eBay, which I clamped in the jig to keep it stable. I had not dressed the wheel when I took the pictures.

Craig

Would it be worth trying to find a General Tool branded jig or are the current $50 ones up to the standard?

Is it easy enough to accurately index the drill 180deg when you grind the other side? I'm guessing there is something that you can adjust that indexes off the flute when you grind the first side?

I can do a decent job of free hand sharpen larger drills but I think a proper jig is going to take some of the 'hit and miss' out of it... especially with smaller drills.

This has been a good read everyone.
Thanks for all the above input!
I'm thinking a diamond lapidary wheel is the way to go Neil. That is a good suggestion.

All the best and Happy New Year,
Ben

Ben, I went for the cheaper "knock-off" version of that jig and it works just fine. It is simple enough to use but I find it easier to take the pivoting part that holds the bit out of the base that gets bolted to the workbench, it just lifts out. That way you can see the face of the drill quite clearly. Sometimes you need to adjust the little index pointer thing that indexes the drill bit to get it to hold the bit in it's right place. Sometimes it needs to be moved either up or down depending on the diameter of the drill bit.
This morning I had to drill 4 of 19mm dam. holes in 2 thicknesses of 10mm steel plate that were sandwiched together. I bored a 4.5mm pilot hole then opened it out to 10.5mm ready for the 19mm hole. I had a freshly sharpened (on a Drill Doctor 750 machine)19mm bit and cutting fluid. That drill got about 10mm down and would not cut any more. I sharpened it on the "Draper" jig (similar to the General Tools jig) and finished off that hole and drilled the other three. The bit was still cutting OK at the end. Best $53 I ever spent and just 10% of the cost of the Drill Doctor.