The Correct Way To Sharpen Drill Bits Using A Picador Drill Sharpening Jig With Custom Base

[DalboyParticipant @dalboy]

Something worth looking at about sharpening using this type of jig.

Unfortunatley you may need to sign in It links to a PDF which I have but can't insert here

Edited By Derek Lane on 01/06/2022 13:20:42

[Richard Kent 1Participant @richardkent1]

Graham Meek – Looks great Graham.

If someone has the time and inclination for modifications etc then they should go for it.

I tried to keep the original post as simple as possible for those people who want to use the original Picador jig which I found works as described if set up properly.

R

[Richard Kent 1Participant @richardkent1]

Derek Lane – Thanks for the info Derek

[JasonBModerator @jasonb]

is it just my eyes or do the sharpened drills have rather long central chisel edges?

[Richard Kent 1Participant @richardkent1]

JasonB – Thanks for the info.

Some clever comments here today – Not your eyes- it's photographic distortion – 2D representation of a 3D object.

The bits were ground according to the instructions.

They drill and work perfectly fine.

Just like new drill bits.

P.S just double checked them by eye against the photos and it is indeed photographic distortion.

The best way to evidence this is for someone else to grind some bits on their Picador jig and compare the results.

Or perhaps send me a drill bit and I will sharpen it and send it back to you for testing?

Edited By Richard Kent 1 on 01/06/2022 13:46:07

[peak4Participant @peak4]

Posted by Richard Kent 1 on 01/06/2022 13:29:44:

…………………………………………..

The best way to evidence this is for someone else to grind some bits on their Picador jig and compare the results.

Edited By Richard Kent 1 on 01/06/2022 13:46:07

There's a few comparative photos in this thread, the first post of which has a link to a different thread again.
https://www.model-engineer.co.uk/forums/postings.asp?th=139828

Bill

[Richard Kent 1Participant @richardkent1]

peak4 – Thanks for the link Bill

If anyone is interested in talking about comparative results then they are welcome to do so.

I say "fill your boots"

As for my setup works perfectly well for me.

I am getting consistently good results.

As mentioned earlier, if someone wants to send me some drill bits for interest sake I can sharpen them and send them back.

[bernard towersParticipant @bernardtowers37738]

Just came across this thread and am a little confused as you say that you use silicon carbide wheels. I have been under the impression for the last 40 plus years that that material is for soft materials and carbides but am ready to be told otherwise. and as for grinding on the side of the wheel is NO NO NO the reason being is that when using the front face the wheel is in compression but on the side you are trying to separate the bond. Ask Norton abrasives what they think.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by bernard towers on 01/06/2022 22:42:57:

… Ask Norton abrasives what they think.

.

The trouble is … they put out stuff like this:

.

MichaelG.

.

Edit: __ You may [or may not] be interested to read the current H.S.E. Guidance, which I linked in this recent thread:

https://www.model-engineer.co.uk/forums/postings.asp?th=177532

My post timestamped : 20/03/2022 08:27:45

Edited By Michael Gilligan on 01/06/2022 23:19:32

[Richard Kent 1Participant @richardkent1]

Michael Gilligan – Mike, thanks for your post. Please see my reply to bernard towers above….

Edited By Richard Kent 1 on 02/06/2022 09:50:33

[Mark RandParticipant @markrand96270]

I will admit that when I'm using my Picador jig, It's on the surface grinder rather than on the side of the pedestal grinder. This it actually far superior to the pedestal grinder setup. One can advance the feed with the cross feed of the grinder instead of the nasty nut on the jig, this gives a repeatability of a tenth of a thou, which is better than the rest of the jig can achieve.

One can then grind one side of the drill, wind the feed back, rotate the drill, then grind the other side to the same amount all without having to keep flipping the drill over multiple times.

Picador did make a larger jig, for drills over 3/4". Those are as common as rocking horde leavings.

[HopperParticipant @hopper]

I have one of those Picador type jigs brand new in the box that has sat unused under my grinder bench for at least 7 years since I rescued it from an old guy's shed where it sat for I don't know how long. Still not sure after reading all this if it's worth setting up. It is on my Round Tuit list though. I have spare 6" grinder and piece of board to set it up on. Might look at making some better fine adjustment screws etc for it after reading above comments. Something in 40TPI with a micrometer collar to really dial it in could be a nice little project.

Meanwhile, an extra seven years of practice at freehand sharpening and I get by ok. Anything under 1/8" is a challenge due to eyesight these days though.

Edited By Hopper on 02/06/2022 10:25:04

[Richard Kent 1Participant @richardkent1]

Mark Rand – Mark, appreciate your comments.

I was showing how it can be done with a 'minimal' setup

If you have a surface grinder then that is great.

Regarding the Picador mounding bracket. As you can see from my photos, I fabricated a new one.

The bracket is only used to offer up the drill to the grinder for the first 'cut' and beyond that you use the screw on the Jig for successive 'cuts' which ensures you keep the drill profile correct as you take more material off the drill bit.

R

Edited By Richard Kent 1 on 02/06/2022 10:31:16

[Richard Kent 1Participant @richardkent1]

Hopper – A picture of my mounting board below……………

[Nicholas FarrParticipant @nicholasfarr14254]

Hi, there seems to be many opinions of how to use these attachments and here are three that say you should use the face of the wheel, Draper images- amazon.com Iinstructables.com. If you must use the side of the wheel, in my opinion and the way I was told in my Abrasive Wheels Course, is it should only be very light and should be as close the face as possible, where any wear will be dressed out during normal maintenance of your wheels and you should avoid dressing the sides of the wheels and certainly not using a star wheel dresser. one of the worse illustrations I've seen, is this one where it is shown near the centre of the side of the wheel, where you really don't want to weaken your wheel Sealey,

Regards Nick.

[Richard Kent 1Participant @richardkent1]

Nicholas Farr – Hi Nick – Thanks for your comments. The way you have suggested do this is the same way as the Picador instructions – taking small cuts. It is interesting to hear other people's point of view.

Edited By Richard Kent 1 on 02/06/2022 11:34:38

Edited By Richard Kent 1 on 02/06/2022 11:34:52

[DalboyParticipant @dalboy]

If safety is a concern then change to a slow grinder with one of these WHEELS it eliminates the worry of grinding on the side of a normal grinding wheel

[Richard Kent 1Participant @richardkent1]

Derek Lane – Derek, I did look at those diamond wheels.

So far the Silicon Carbide wheel from …………………………….. has been performing fine.

https://www……………………………………………

However, I have the choice of either upgrading or reinforcing my existing wheel.

One way of doing that is to bond a plywood or aluminium disc to the opposite face of the grinding wheel with Epoxy Resin Adhesive.

That way the wheel is unlikely to suffer any sudden fracture.

I have also been improving my Ducking Skills so if that should happen the wheel should theoretically go over my head and miss me completely! 

R

Edited By Richard Kent 1 on 02/06/2022 11:48:13

Edited By JasonB on 05/06/2022 18:37:55

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Richard, I don't know how you can reinforce your grinding wheel by bonding anything to the opposite side of it when the flanges that grip the wheel with the blotters should be of equal diameter and have an equal bearing area.

Mounting the wheel

Regards Nick.

[Richard Kent 1Participant @richardkent1]

Nicholas Farr – Nicolas, this is where too much reading and knowledge can be dangerous

Bonding a reinforcing disc to one side of the wheel should not present any issues in theory.

I'll let you know the results if I take that option.

R

[SillyOldDufferModerator @sillyoldduffer]

Posted by Richard Kent 1 on 02/06/2022 14:28:51:

Nicholas Farr – Nicolas, this is where too much reading and knowledge can be dangerous

Bonding a reinforcing disc to one side of the wheel should not present any issues in theory.

I'll let you know the results if I take that option.

R

Too much reading and knowledge are never dangerous. It's getting stuff wrong in the workshop that causes real damage!

Dave

[Richard Kent 1Participant @richardkent1]

SillyOldDuffer – Dave, Don't take my flippant or sarcastic comments too seriously as they are not meant to insult.

On a more serious note. Reading and knowledge is great but must be kept in context and balanced with alternative views.

Example in this post: Grinding wheel manufactures advise against grinding on the side of a grinding wheel. So based on that information alone you would not do it.

However, the Picador jig instructions say that it can be done providing you take small cuts.

Each individual should do their own reading on a subject and I am not suggesting anyone else has to follow what I do.

What I would recommend is that if anyone is going to do any engineering which deviates from the norms (including grinding on the side of a grinding wheel) then ensure you mitigate any risk with appropriate PPE etc.

Regarding your quote: "Too much reading and knowledge are never dangerous. It's getting stuff wrong in the workshop that causes real damage!"

That was an implicit statement

My workshop techniques are fine thanks very much

I don't want anyone getting their knickers in a twist over a drill grinding jig

This is not engineering advice so do not follow what I do 

Edited By Richard Kent 1 on 02/06/2022 16:23:00

[Anonymous]

Posted by Richard Kent 1 on 02/06/2022 14:28:51:

Nicholas Farr – Nicolas, this is where too much reading and knowledge can be dangerous

Bonding a reinforcing disc to one side of the wheel should not present any issues in theory.

I'll let you know the results if I take that option.

R

Perhaps you should do more reading and gain a bit of knowledge then. What is this "Theory" you are on about, all guidelines from manufacturers and training say to use equal flanges to give an equal clamping force, a wheel should be perfectly balanced for it's high r.p.m. or you are really asking for trouble. Bonding a piece of ply or alloy to one side is probably the worst bit of workshop practice I've heard.

[Richard Kent 1Participant @richardkent1]

Bezzer – "Bonding a piece of ply or alloy to one side is probably the worst bit of workshop practice I've heard"

Great I'll try it and let you know what happens

Could work perfectly well

This is NOT engineering advice so do not UNDER ANY CIRCUMSTANCES follow what I do

Edited By Richard Kent 1 on 02/06/2022 16:27:48

[Anonymous]

Posted by Richard Kent 1 on 02/06/2022 16:13:29:

Bezzer – "Bonding a piece of ply or alloy to one side is probably the worst bit of workshop practice I've heard"

Great I'll try it and let you know what happens

Could work perfectly well

This is NOT engineering advice so do not UNDER ANY CIRCUMSTANCES follow what I do

Edited By Richard Kent 1 on 02/06/2022 16:27:48

I can't make my mind up if you are a troll or actually that far up yourself. Either way it doesn't matter as as the ignore button is about to be pressed , joining a few others I suspect.

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