Wandering drill bit

[LD1]

Your. pilot should be just big enough to provide clearance for the Web of the drill.

Agreed.

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.

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!!

Once you go above 1/2", Most drills are chisel point and Split point. Meaning that they cut much better with a pilot hole that is the size of the chisel.

But stepping up sizes in small increments like you guys mention is MUCH harder on bits, MUCH more likely to grab and twist the drill out of your arm, And takes longer anyway.

The way a drill bit is cut, the closer the the edge you get, the more aggressive the attack angle of the cutting edge. That in combination with only trying to take a small cut (say from 1/2" up to 3/4") puts you are great risk for the bit grabbing, and actually fracturing the tip.

You want as much meat of the cutting edge doing work as possible to minimize grabbing and broken drills.

I have to work with people that have that "step up 1/8" or 1/4" each time mentality. The result is a ton of 1/2"-1" chisel point bits that have chipped/busted/cracked cutting edges right out at the edge. Some people just refuse to learn. This is even with proper drill presses. Including a huge 15HP Radial Arm:mur:

 

[meos1]

I like that kit. Next on list! Just for the record here is how I did it. It took all of a half an hour for both holes... use punch to make small divet, drill with step drill (now its off center and is not the final size), Carbide burr on a air powered die grinder to make the hole the correct size. Use step bit at 3/4 to cut the jagged edges off the inside and out. DONE! But you are all correct. I should have preped more. Its (the steel) thicker than I generally deal with and harder as well. So lesson learned. I am looking for a spreader bar to mount over the bucket and use as a mount for the grapple I want to build. So I will be drilling at least four more holes...

 

[Sodo]

use punch to make small divet, drill with step drill (now its off center and is not the final size)

More some monday morning qtrbackin'
If a (normal) bit wanders, stop ASAP and weld up the divit and re-punch in the correct location. Agreed with those above, stepping up incrementally (especially handheld) chips the corners of the bit and often overheats them anyway, use a pilot hole slightly larger than the web of the final bit.

How you did it is often how I do it, and what I wrote above is how I shoulda done it (too).

 

[PapaPerk]

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.

Yeah I used a 3/4" holesaw instead. Cuts like butter! (0;

 

[PapaPerk]

Here's the link to my PTB review and install. I have pictures showing how I installed. Note I'm using a hole saw for large hole. Installed it in probably 10 mins.... Not including getting tools out.

http://www.tractorbynet.com/forums/attachments/309127-72-piranha-tooth-bar-install.html

 

[meos1]

I took it to the woods yesterday and it performs! Rips out whatever you point it at.

 

[PapaPerk]

I took it to the woods yesterday and it performs! Rips out whatever you point it at.

Yeah makes a huge difference in bucket performance. Love mine.

 

[LD1]

Yeah makes a huge difference in bucket performance. Love mine.

No pictures.....It didnt happen

 

[oldpilgrim]

rather than using bolts, could you use some sort of pin that would facilitate removal and re-installation? Or would that leave things too loose?

 

[PapaPerk]

rather than using bolts, could you use some sort of pin that would facilitate removal and re-installation? Or would that leave things too loose?

It would be too loose. Need a good clamp to the bucket