Wandering drill bit

[meos1]

Out in the garage last night installing the new PTB. I used a punch and hammer to set a starting point for the hole. Before its over I have a hole off center. Off to the hardware place for a carbide bit for the air grinder. At least its not the weekend.

 

[LD1]

Wandering bits is a problem when hand drilling. Especially smaller holes. Unless you can keep the drill perfectly straight, and apply just the right amount of pressure, you get wander.

Push too hard, and the bit flexes and wanders. Dont hold the drill perfect, and it wanders.

Any more details? What size hole were you drilling? How thick was the material? What was the material? Hand drill?

 

[meos1]

Yep, hand drill....I was drilling out the FEL bucket to 3/4" The carbide burr will clean up my error.

 

[Indygunworks]

I when drilling small holes like that I like to use a 45 degree chamfer bit on the punch park to open the area up for the small drill bit a tad.

 

[Brad_Blazer]

I when drilling small holes like that I like to use a 45 degree chamfer bit on the punch park to open the area up for the small drill bit a tad.

Yeah, 3/4" with a hand drill is so small I usually just chuck that up in the Dremel LOL.

Seriously, about a 3/16 pilot hole might have helped keep it centered. A magnetic base drill is the best tool for that job.

 

[s219]

I have an old set of centerdrills from a milling machine that sometimes help prevent walking with a hand drill. They are so thick, there is no concern about flex or breaking, so it's ok to lean on them. There's always a "just right" amount of pressure in many cases.

 

[LD1]

Yep, center drills do wonders. They do cut slower though.

IF no mag drill available, best trick is to use a center drill and drill as deep as the chamfer on the center drill. (IE: drill intil you would start creating a hole the full diameter of the center drill).

if that is not enough to get all the way through the material thickness, use a small pilot bit that is the diameter of the TIP of the center drill. Drill that all the way through and then proceed with the 3/4" bit.

 

[meos1]

Carbide burr and we are done and done. Just bolted it on and it looks good. I love air tools.

 

[Yellowhair42]

Yep, center drills do wonders. They do cut slower though.

IF no mag drill available, best trick is to use a center drill and drill as deep as the chamfer on the center drill. (IE: drill intil you would start creating a hole the full diameter of the center drill).

if that is not enough to get all the way through the material thickness, use a small pilot bit that is the diameter of the TIP of the center drill. Drill that all the way through and then proceed with the 3/4" bit.

The best way I have found is to make a nice well formed center punch where you are going to drill. Then use an 1/8th diameter drill to make a hole slightly deeper than the angle on the tip of drill bit of the finished size. Then drill to desired depth with 1/4 diameter. Then the 3/4. A drill bit will always follow the pilot hole.

 

[LD1]

The best way I have found is to make a nice well formed center punch where you are going to drill. Then use an 1/8th diameter drill to make a hole slightly deeper than the angle on the tip of drill bit of the finished size. Then drill to desired depth with 1/4 diameter. Then the 3/4. A drill bit will always follow the pilot hole.

IF that works for you. I personally hate small diameter bits. I dont like using anything less than about 3/16" unless I absolutely have to.

 

[PapaPerk]

Center punch with sharp point punch and hammer. Good deep punch. Then use a nice SHARP good quality drill bit... 1/8" to 1/4". Should cut like butter with no wander as long as you hold drill straight. It's all in having a sharp bit and holding straight. A little cutting oil on bit always helps.

 

[sandyc]

I'm going to send this thread to my dentist. Ouch!

 

[deerseeker001]

That is what I use is a center punch.

Center punch with sharp point punch and hammer. Good deep punch. Then use a nice SHARP good quality drill bit... 1/8" to 1/4". Should cut like butter with no wander as long as you hold drill straight. It's all in having a sharp bit and holding straight. A little cutting oil on bit always helps.

 

[meos1]

I learnt...Its on and I just tested the PTB - Its awesome.

 

[newbury]

Center punch with sharp point punch and hammer. Good deep punch. Then use a nice SHARP good quality drill bit... 1/8" to 1/4". Should cut like butter with no wander as long as you hold drill straight. It's all in having a sharp bit and holding straight. A little cutting oil on bit always helps.

I used a potable drill guide to keep it really straight.

 

[DuckSlayer1017]

A 3/4 " hole is a big hold to drill by hand, not that it can't be done but you will have to push really hard and will have to watch out in case the drill bit catches. I would go in this order:
1. Punch
2. Center Drill
3. 1/4" pilot drill
4. 1/2" pilot drill
5. 3/4" drill
Stepping up the sizes helps get through with less force. Basically drill your pilot hole so the tip of the next size drill bit will fit inside the pilot hole. The tip of the bit has the most resistance so using a pilot hole will greatly reduce the force required to drill the hole.

 

[Sodo]

Meos1, glad you got it done.

Here's some tool-talk.

Well now that I have rota-broaches, drilling 3/4" is just "easy". This thing doesn't wander, it stays right on your centerpunch and drills an annular hole AROUND your original punch.

It's like a holesaw, but makes a super precision hole, it doesn't triangulate like a 2-fluted twist drill. I do 3/4 easy with my 18v rechargable drill. It's faster and takes less power because you don't turn the whole plug into chips.

Here's the kit I got for recently $65, couldn't be happier. It' made in USA! It's called a sheet metal cutter, and only drills 1/4 " deep, if you are drilling thicker metal you have to come at it from both sides, which you have to drill a tiny hole thru to locate the other side. In some cases you can drill down to 1/4" then drill out the plug with a normal bit, and then keep going.

 

[deanwerden]

Your. pilot should be just big enough to provide clearance for the Web of the drill. step drills work awsome I have one that goes to 3/4. center drill first

 

[Scooby074]

As mentioned above, use a good wide centre punch (Starrett 264G as an example), then a proper centre drill to make a divot so you wont wander. After that, 1/4", 3/8, 1/2 and finish at 3/4. Generally speaking I use the same series of common sized bits leading up to finish size so that I only have to sharpen or replace the 3 "pilot" (1/4", 3/8, 1/2) sizes.

Rotobroaches are awesome in their own right!!

 

[k0ua]

Meos1, glad you got it done.

Here's some tool-talk.

Well now that I have rota-broaches, drilling 3/4" is just "easy". This thing doesn't wander, it stays right on your centerpunch and drills an annular hole AROUND your original punch.

It's like a holesaw, but makes a super precision hole, it doesn't triangulate like a 2-fluted twist drill. I do 3/4 easy with my 18v rechargable drill. It's faster and takes less power because you don't turn the whole plug into chips.

Here's the kit I got for recently $65, couldn't be happier. It' made in USA! It's called a sheet metal cutter, and only drills 1/4 " deep, if you are drilling thicker metal you have to come at it from both sides, which you have to drill a tiny hole thru to locate the other side. In some cases you can drill down to 1/4" then drill out the plug with a normal bit, and then keep going.

I always figured those were more expensive than that. That is not a bad price, with no shipping delivered to your door by the brown truck.