Drill Dr.

[slim67 2,735]

7 hours ago, WVHillbilly520H said:

I learned to grind drill bits while working as a machinist in training but most of our bench grinders had a rest with the correct angle to follow. But after learning the basics a belt sander works just as good especially for larger say 3/4" and up. Also depending on material you are working with aluminum,brass, bronze, tool steels, or more common low carbon steels cold/hot rolled ect, or even wood sharper or flattering angles are needed for better smoother faster cutting than the standard 118° or 135° angles as I was taught by my mentor being in the trade for 40 years, the biggest thing to remember is to have a thin sharp cutting edge on both sides with enough chip relief below that edge as not drag in the bottom of the hole you are trying bore. Then speed and feed and lube depending on materials plus don't try to drill a 3/4" hole in 1 pass step it up (under 1/4" single pass should work) at least 2-4 sizes till the one you want works best then of course a 60° center drill helps greatly too.

I like that piece on the grinder . Is that an add on or something you made?

[Zeek 2,286]

On 12/19/2020 at 7:03 PM, DennisThornton said:

I think I paid $19.95 for a HF set 1/16th -1/2" by 32nds of Titanium coated.  

Worth every penny but not much more...

Same exact thing here. Same opinion. I drilled through frame steel on an RV successfully using oil, but the smaller ones snapped easily when in a drill press.

[WHX?? 49,190]

1 hour ago, slim67 said:

I like that piece on the grinder . Is that an add on or something you made?

Probably came with the grinder. One of mine has is too. 

[WVHillbilly520H 10,374]

2 hours ago, slim67 said:

I like that piece on the grinder . Is that an add on or something you made?

No that's factory , but I remember the last place I worked at actually bought "universal" replacements that had those angles "molded" in... My HF reference to centerdrills was just that an image reference, I do buy a lot of stuff there but also know what NOT too.

[Horse Newbie 7,130]

On 12/19/2020 at 5:42 PM, DennisThornton said:

because I haven't yet learned after 50 yrs that you can't put your entire weight on them!

Me too !

[WVHillbilly520H 10,374]

I must be slipping in my "old" age... It just occurred to me take a fresh drill bit (3/8" for instance) and lay it on your (not running) bench grinder rest with the cutting edge butted up against the center of the wheel/stone then either with a paint pen or scribe (or both) then  mark along side of the bit , now you have the angle guide to help keep you close for holding the factory angle... Happy grinding.

[formariz 11,988]

5 minutes ago, WVHillbilly520H said:

I must be slipping in my "old" age... It just occurred to me take a fresh drill bit (3/8" for instance) and lay it on your (not running) bench grinder rest with the cutting edge butted up against the center of the wheel/stone then either with a paint pen or scribe (or both) then  mark along side of the bit , now you have the angle guide to help keep you close for holding the factory angle... Happy grinding.

I use sometimes quite different angles on them depending on what I am drilling. The factory angle is usually best for steel. However I find that on other materials different angles work better. Even in wood which they are really not the ideal for different angles work better in different wood species depending on how hard or soft they are. It also makes a big difference on their "walking" when starting a hole.

[ebinmaine 68,481]

5 minutes ago, formariz said:

walking

I realize this thread isn't about the use of drills but about the sharpening of them so I don't want to get too far off topic but,

 

I am at best, a country hack that attempts to throw a few things together here and there. I've always been in the habit of using a small punch or a very small drill to make a starting point to prevent walking.

 

Is there something I could or should be doing differently?

 

 

[WVHillbilly520H 10,374]

42 minutes ago, formariz said:

I use sometimes quite different angles on them depending on what I am drilling. The factory angle is usually best for steel. However I find that on other materials different angles work better. Even in wood which they are really not the ideal for different angles work better in different wood species depending on how hard or soft they are. It also makes a big difference on their "walking" when starting a hole.

Yes sir, I mentioned that earlier in post 25 as well as using a center drill for starting holes, my machinist mentor was old school ,ground a lot of "specialty" tool bits for the lathe and his router for one of his other passions woodworking not to mention blacksmithing, I paid attention to him, I was just trying to help out the "novice" drill bit sharpeners with the guide marking tip on the grinder rest, starting with the basics here like I was taught at first and learn the small tricks as you go, you sir are a master craftsmen in my book and I'm sure you will agree that starting with the "baby" steps and working up to the next levels is a good way to learn your craft at hand.

Edited December 22, 2020 by WVHillbilly520H

[formariz 11,988]

33 minutes ago, ebinmaine said:

I realize this thread isn't about the use of drills but about the sharpening of them so I don't want to get too far off topic but,

 

I am at best, a country hack that attempts to throw a few things together here and there. I've always been in the habit of using a small punch or a very small drill to make a starting point to prevent walking.

 

Is there something I could or should be doing differently?

 

 

What you are already doing is good and correct. It is however not always possible or convenient to use a punch for many different reasons. One instance is when working out in the field that one usually forgoes that formality. Another example is the material one is drilling. I work with all types of plexiglass, lexan, etc, and a punch is not kind to those materials specially if its close to an edge. As an example there you need a bit with a much steeper angle. Drilling first also with a smaller bit in those instances is a no no. The final bit may catch and crack the work.

One also has to be careful as to the type of tip the punch being used has, meaning how pointy  and how wide. If done incorrectly punched hole has a burr which will lead a shallow angled bit to go into the side rather than in center.

Most don't need to worry about all this but if one works with many different materials many different conditions are required.

Edited December 22, 2020 by formariz

[WVHillbilly520H 10,374]

30 minutes ago, ebinmaine said:

I realize this thread isn't about the use of drills but about the sharpening of them so I don't want to get too far off topic but,

 

I am at best, a country hack that attempts to throw a few things together here and there. I've always been in the habit of using a small punch or a very small drill to make a starting point to prevent walking.

 

Is there something I could or should be doing differently?

 

 

You could buy yourself a 5pc set of "center drills" like I posted before, just remember the small points are easily broken if forcing them, you can use them with a hand drill but drill press is better (if you have access) as you have a better feel for pressure , again just my experiences.

[ebinmaine 68,481]

5 minutes ago, WVHillbilly520H said:

You could buy yourself a 5pc set of "center drills" like I posted before, just remember the small points are easily broken if forcing them, you can use them with a hand drill but drill press is better (if you have access) as you have a better feel for pressure , again just my experiences.

I do actually have a fair noname '70s or earlier manufactured stand up floor model drill press I inherited from my Grampa. 

We just recently moved it from the outdoor workshop into the basement so as to be better maintained and better utilized. 

 

Is there a center drill set that is inexpensive but not garbage that you might recommend?

 

[WVHillbilly520H 10,374]

11 minutes ago, ebinmaine said:

 

Is there a center drill set that is inexpensive but not garbage that you might recommend?

 

That's the thing inexpensive and not garbage, working in factories Morse brand was a go to but not cheap, you might try Grizzly, the HF versions I don't think would last long at all. Or these https://www.ebay.com/itm/353290893950. A 3pc set from MSC is $60.