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Drilling an accurate hole


#1

I often am asked how to drill a hole straight by my students, so I made a 30 second video showing the motion of the quarter turn and drill method.

Cheers,

Hans


#2

Thanks Hans for posting this. When I am teaching I tell my students the same thing. I stand over them and nag them. I warn them about this ahead of time. "I’m gonna drive you all crazy until you do this automatically. “Rotate,rotate, rotate.” Also “Use your bench pin, use your bench pin.” Drives them crazy but they thank me in the end.
Have fun and make lots of jewelry
-Jo Haemer
www.timothywgreen.com


#3

Thank you for posting this. Very informative.


#4

Thanks for the post. Something that should be straight forward but is also so important!


#5

There seems to be a lot of discussion about drilling a hole. Get a piece of brass 2-3mm thick, a package of #70 drill bits and some bees wax. Drill 300 holes. Make each one as straight as you can. You’ll get better. There is no magic secret. no trick. Like anything worth learning- dancing, diction and drinking tequila. Have fun. tom


#6

The real secret to drilling a straight hole right where you want it is not having the drill slip.
Do what machinists do. They use two punches. One it 60 degrees and the other 30 degrees.
Once you have located exactly where you want to drill your hole. Use the 60 degree punch to make
a dimple. The use the 30 degree punch to enlarge an flatten this dimple. This will give you a dimple large enough for the head of your drill bit so it won’t slip out. Why two punches? Machinists have learned over the years that when you try to punch with a 30 degree punch, it will skid over the metal. A 60 degree punch will dimple the metal slightly and not skid.
the dimple can then be enlarged with a 30 degree punch.


#7

Yoe can make 30 centerpunches with different angles and still not producing a straight hole. This has nothing to do with how to drill a straight hole. The point of your drill is so small but has a definned little line. That little line is the bad guy who can’t find a specific place to stay. By using a centerpunch but it has to be at that size that this little line fits in that hole. You decide where this place is going to be by making this opression.The centerhole is the start of drilling and that’s it. Further drilling has to do with the angle of your handpiece to your workpiece. That is the difficult part. Big burs are another story but we are talking about holes of 1mm or less. Practice does it like Tom Arnold already stated.


#8

Drill 300 holes.

I’m totally with Tom on this! Being able to drill a round straight hole is one of the many skills any ‘real goldsmith’ should have…:-)… If you have to keep rotating the hole to get it round, it means you are not holding the drill 90 degrees to the face of the sheet, and your hole 1) will come out larger than the drill size, and 2) the walls of the hole will be angled. Learn to drill straight. Do it by drilling 300 holes–or however many you need to get it right…:-)…


#9

Hi Everyone on this topic! Re; "Holes for Diamond Setting"
When I have to drill holes for Diamond Setting…my own method is to use a round bur @.008mm this will act as a guide for the next size up! I never, repeat! never “punch”, it might bend the gold or silver that I’m working on! I use the .008 mm round hole just as a ‘guide’ for the exact location. Being exact, while in setting, is paramount !! For depth of the bur…this bur should go deep as the head of the bur is into the metal. It is here I will use the twist drill, this size is for the Culet of the stone, nothing else!! The next size larger is almost (80%) the size of the “Pavillion” of the gem-stone. I will use a large selection (4-5) of burs & twist drills.
“Punching holes” is not in my setting vocabulary. BTW, make darn sure your twist drills & burs are sharp! I’d even select a new round bur, no slipping on the metal for this initial bur cut. Hope this helps!
(gerrylewy18@gmail.com)


#10

If your guiding hole is out of line all other will be too Gerry.
Drills and burs always need to be sharp, you’re spot on with that one.

I recommend people to drill as many as possible using a punch “wisely” as a mark not as a predrilled hole.
If one does it right that little deformation of metal along the drill hole is not visable afterwards.
If one gets so damn good in drilling holes exactly, it’s up to the person to decide when to use the punch or not.

I’m very cautious with the words “never” and “always”.
I’ve learned they can trick you.


#11

I suggest to use a scribe on the metal, to initiate even the 'temporary’
drill holes. Once the ‘bur-touching’ of the metal appears in line with the
others…then proceed further! As a setter, I’ve got accustomed to drilling
and this process gets loads easier by the ‘fifth decade’…:>)

Gerry Lewy

www.gemsettingtutor.com http://www.gemsettingtutor.com


#12

Thank You @Bill.Tokyo for bringing up the subject of the punches with different tip angles.

If I understand correctly, the 30 degree punch (aka: Prick Punch), with it’s slim tip, is used in layout to create slight indentions as reference points, not only for the purposes of cutting or pre-center punching for drilling, but also to easily catch the scribed intersection of 2 lines to make a slight indention where you can plant a leg of your divider.


#13

Does the type of drill bit matter at all or just as long as you are using a twist for metal you’re good to go?


#14

Well said Aloped!


#15

Hi Betty 2

It’s the 60 degree angle layout punch that’s used to make the first dimple, not the 30 degree, but otherwise you have it exactly right. The 60 degree punch leaves a small sharp indentation and it’s ideal, as you suggest to catch the scribed intersection of two legs to plant your divider. Thanks for a great tip! Now why didn’t I think of that?

I might add that machinists spend a great deal of time making sure the layout of their designs on metal,is just right and some of their techniques may be of use to the jeweler too.


#16

There are a wide number of drills in many different conformations, and they have very different characteristics.
A twist of metal won’t do. You’ run the chance of skittering all over the surface of whatever you’re doing, because they have no sharpened leading edge to cut into the metal. The drills used most commonly by both jewelers and machinists are twist drills. These have precision cut angles on the tip of the drill to draw the drill through the hole as straight as possible. These are called HSS drills-High Speed Steel-and are actually made for drilling the softer varieties of steel, plus aluminum and wood. They are not great for copper, brass or silver. For copper and brass the angle has to be recut. For silver, which is a “sticky” metal, you should use various commercial drilling lubes on the market.

There are literally hundreds of shapes in the bits for flex shafts that can make holes. But these are grinding away the metal, not cutting it, and you have somewhat less control.

I won’t get into hand drills, such as pump drills where you can use flat metal sharpened on one edge and other configurations. They’re harder to use accurately, but like all other hand tools, life savers when you hit a situation you just can’t do with power tools.

Don’t forget, I’m a watch maker and drilling is more important in my trade (art?) than is is in jewellery.


#17

Thanks for replying. When I said “using a twist for metal” I was referring to twist drill bits, I should have stipulated that. I was recommended a drill set by my teacher, but the class was geared more towards metalsmithing (not necessarily jewelry) and the drill bit set is your typical “hardware” industrial twist drill bits. The reason I asked is as you stated, there are so many options available I wondered what other people preferred to use or if industrial type twist drill bits were “good enough” so to speak (silver, bronze, stonesetting, etc).


#18

Hi C3ntury
Industrial twist drills are what I’m calling HSS drills. Same thing. It’s what you find in any hardware stone. They’re good enough for everything. However, if you are drilling a lot of copper or brass you might want to resharpen your drill bits specifically for brass and copper. Also, sharpen your drill bits occasionally, or just throw them out and buy new ones. Youtube has dozens of DIY videos for sharpening drill bits. Also, I might add a very handy tool in my shop for drilling is my home made drill press. If used with a vise, it makes drilling very easy and accurate. Once again, a visit to Youtube will give hundreds (literally) of DIY schemes for drill presses. As I point out, I’m a watch maker , so my needs might be quite different from jewelers, but I find having a small drill press handy.


#19

@Bill.Tokyo
Is the 60 degree punch aka a Center Punch?


#20

Yes, it is. They’re the two types I mentioned. my 60 degree punch is pretty dinky while my 30 degree punch is much larger. I suppose that’s so you don’t get them mixed up in the dark.