Perfectly ground Twist Drills every time.

[Clive IndiaParticipant @cliveindia]

The Quorn can be used to grind 4-facet drills. It can be used for many tasks but It seems to me its principles of drill grinding could be used in a relatively simple jig. The requirements are a grinding wheel and a clamp for the drill.

From above the angle of the drill needs to be set at 59deg from the wheel face. This gives the point angle of 118deg and does not change.

From the front (In the vertical plane) the drill must be tilted 10deg and 30deg from the vertical for the two facets.

The only other requirement is to start with the drill in the right orientation and turn the drill through 180deg to grind each side.

Surely someone has already done this?

[Keith LongParticipant @keithlong89920]

Clive India

Have a look at the following website the model 80M – is that along the lines that you were thinking of?

I have a very similar machine picked up from EBay but made by Haase GmbH & Co. – not used it yet but it looks quite capable and VERYsturdy and solid. The principle is simple enough but I suspect it's all down to how accurately you can make one and how rigid it is when finished. The drill holder works on intersecting "v" shaped fingers to hold the drill so centre height is maintained regardless of diameter, which is from approx 1/16" to 13/16"

[Clive HartlandParticipant @clivehartland94829]

Here's what you want, no problems apart from a limit on the size of drill being ground.

[Chris SheltonParticipant @chrisshelton11794]

Hi All, does anyone own or have any knowledge of the Holzmann BSG 13E drill sharpener,being sold on eBay For £59.95, states it has a die-cast chassis and weighs 2.5Kg.

Chris

[capnahabParticipant @capnahab]

Anyone ?, I have also spotted this , looks better made than many .

[John Stevenson 1Participant @johnstevenson1]

More or less a copy of the drill doctor ?

Still has a load of plastic on board and the bit I'm uncertain of is the 80 watt motor driving a 78mm wheel.

The current drill doctor has about a 25mm grinding wheel but I can't find any info on the motor wattage but from using one it's underpowered. Also in the genuine Drill Doctor user guide it reckons 200 sharpening from a £33 wheel ?

[Ady1Participant @ady1]

I recently got some good drills from the relative of a long gone British Aerospace engineer who did stuff like gyroscopes and tooling for surgeons

His drills all have a tiny land ground at the point to extend the drilling point workzone

[John Stevenson 1Participant @johnstevenson1]

That's called point thinning. Very common because as a drill reduces in length the central web gets thicker for strength.

[VicParticipant @vic]

I never knew that John.

[AndyPParticipant @andyp13730]

I got one of the Holzmann drill bit sharpeners mentioned today and have been playing with it this afternoon. Seems a solidly built unit and the "plastic" bits are thick and hard rather than flimsy. There is a video on the German parent website here .

I am not sure about the angles it produces though, the first grind, I'll call it cutting looks too shallow to me and the clearance angle grind which is done second barely touches the back of the cutting edge.

First picture shows after the main grind of the cutting edge…

And after the clearance angle has been ground

Not sure whether to return it or not.

Andy

[Chris SheltonParticipant @chrisshelton11794]

Hi Andy,

I also bought one in the end, very pleased with it, but before you grind the clearance angle, you need to reset the drill position in the holder again.

HTH

 

Edited By Chris Shelton on 13/05/2015 16:49:14

[AndyPParticipant @andyp13730]

Hi Chris,

That certainly takes more off but neither the instructions or the video mention resetting the bit between grinds, the video clearly shows doing one then the other all in one camera shot. It doesn't look right to me :-

[Chris SheltonParticipant @chrisshelton11794]

Hi Andy

Not sure how to put youtube links on the forum, but if you look at the tradetools tv review of a re-badged version of the drill sharpener, he states you should reset the drill after sharpening.

Chris

[AndyPParticipant @andyp13730]

Thanks Chris, so it does, link here , now that is annoying, 2 sets of contradicting instructions for what appears to be the same device. I feel more inclined to believe the manufacturer though.

Andy

[BowberParticipant @bowber]

I learnt to do mine by hand while an apprentice. I was a jig and die maker at K shoes and had to drill thousands of holes a week so we learnt to do them by hand, it’s been handy since as I. get to resharpen my crappy cheap drills.

[Dave HalfordParticipant @davehalford22513]

I would have said from the second pic the drill has been thinned too much. The cutting edge looks to have gone in the center.

I've got a Holzmann myself and I've noticed it's quite sensitive to hand feed variation which can give an off center grind effect if you don't take care.

It shouldn't need resetting for the second grind unless the second grinding station is set too high.

All I have done is regrind on the same setting if it looks off and that seems to fix it.

[Bill PhinnParticipant @billphinn90025]

Can someone tell me is the content from the earlier part of this thread [presumably by Graham Meek] that has been redacted without acknowledgement viewable somewhere?

I've read a lot about Spiralux and Picador drill grinding jigs on this forum and have recently acquired one of each [they look about forty years old at least but are BNIB]. I'm getting pleasing results with the jigs, but would like to refine my understanding of drill sharpening further, and then possibly refine my jigs and technique.

[Tony Pratt 1Participant @tonypratt1]

Quick answer is yes but it will need some digging to find it all. I will have a look but others may be quicker. Just Googled 'Drill sharpening Graham Meek', plenty there to start with.

Tony

Edited By Tony Pratt 1 on 10/11/2022 17:55:34

[Michael GilliganParticipant @michaelgilligan61133]

Bill

… not sure if the van Royen document would help … but here is something to point you in the right general direction [the original hyperlink being useless now]

MichaelG.

.

.

Edit: __ this might be quicker: https://www.model-engineer.co.uk/forums/postings.asp?th=140032

Edited By Michael Gilligan on 10/11/2022 18:32:32

[Bill PhinnParticipant @billphinn90025]

Posted by Tony Pratt 1 on 10/11/2022 17:53:55:

Just Googled 'Drill sharpening Graham Meek', plenty there to start with.

Tony

Edited By Tony Pratt 1 on 10/11/2022 17:55:34

Thanks, Tony, I've Googled this aplenty, but I'm not seeing the "nice work" by Graham referred to by Michael in this thread's opening post, nor the "practical demonstration" referred to by Clive, which presumably illustrates "the improved drill clamp arrangements" summed up by Thor as "advice on improving the jig". I've seen one photo in a later thread on this forum showing Graham Meek's jig set up next to a Clarke grinder, but nothing I could interpret as a practical demonstration.

The following thread too has frustratingly been purged of images and possibly text as well:

https://www.modelenginemaker.com/index.php/topic,3788.0.html

There's clearly some reason for the removal of previously visible material from both forums, but I can only guess what that reason might be.

EtA:

Thanks, Michael, for the Van Royen reference, which has enabled me to find this:

https://www.model-engineer.co.uk/forums/postings.asp?th=140032

The related Graham Meek content is presumably now pay-per-view only in some form.

 

Edited By Bill Phinn on 10/11/2022 18:37:21

[JasonBModerator @jasonb]

It's been completely removed from the system so not even pay as you go.

Though if you know where to look it can be found on the net.

[Bill PhinnParticipant @billphinn90025]

Curiouser and curiouser.

[Frances IoMParticipant @francesiom58905]

no there was a spat several years ago and much useful posting was removed by one of the parties – wrecked many threads (one of which I was very interested in as a newbie) – some of it was salvaged by others, some I think landed up in a book and the rest to the electronic version of landfill – the internet has taken over from libraries but the equivalent of book burning just needs someone to throw a wobbly and there isn’t even a puff of smoke to show what was once there.

Edited By Frances IoM on 10/11/2022 19:44:24

[JasonBModerator @jasonb]

I have pointed Bill to where he can find the puff of smoke that he was looking for, so all is not lost

[Frank GorseParticipant @frankgorse]

Please could you point me there too?

[Author]

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