What metal drill bit for putting a Piranha on?

[newbury]

Well I got the Piranha and the first drill bit was a failure.

My M4700 has a thick lip:


about 0.89 inches and Harry said the step drill probably wouldn't work either.

Since I need a 5/8 drill any recommendations for a good brand? Preferably something quick and local.

 

[PsRumors]

I have good luck with Dewalt branded bits. I abuse the heck out of them for about three years and then buy a new set.

 

[sal64]

looks like .790 to me,drill with 1/4 pilot drill first then this drill Silver & Deming And Reduced Shank Drill Bits | MSCDirect.com go slow be carful it could grab.

 

[RoyJackson]

I would not use a step drill. Step drills are great for relatively thin gage material...say about 1/4" maximum.
I would initially use a small bit (1/8th) for a pilot hole, then a 1/4", then a 3/8ths or 7/16ths...then go to the 5/8ths.

I hope your drill motor has a handle extending from the side...when those larger bits break through, there will be substantial twisting of the drill motor.

Another method, if you don't need a "clean" hole is to pierce the hole(s) using an oxy-acetylene rig with a cutting torch.

 

[RoyJackson]

looks like .790 to me,drill with 1/4 pilot drill first then this drill Silver & Deming And Reduced Shank Drill Bits | MSCDirect.com go slow be carful it could grab.

Look closer...that caliper is at .890 plus a few thousandths.

 

[Dr Dave]

I start with an 1/8 inch pilot hole, I use the short double ended bits, made for drilling rivot holes. These bits wont flex and break, like standard lenght bits. Then step up to 1/4 inch and be sure to go slow about 400 rpm max. Use plenty of cutting oil . Fastenal, Dewalt, Vermont/America, or Crafrsman all work fine, just drill slow and use cutting oil.

Dave

 

[Scooby074]

No step drill.
Start with a pilot, like .250. Then goto .500 then finish with .625

Get a good euro or US brand. Avoid the china crap. Dormer, CL or Triumph are all decent brands.

I dont believe that cutting edge is hardened, but if it is you might need to get a tougher drill than HSS. Use a good cutting oil too, like LPS Gold.

 

[tomfifield]

as said you ned to do a pilot hole first. For hard steel I like using cobalt bits, they are made for this sort of work.

 

[newbury]

I was figuring on a couple of pilot holes, but it looks like I need to go online to get a 5/8 drill. I think I'll ask Harry is 5/8 is REQUIRED because if I'm not finding reduced shank bits I bet others aren't either.

 

[BXpanded]

Personally, if I have to drill something that thick, I start with a 3/16" pilot. The 3/16 is small enough to drill pretty easily, but stiff enough to stand some pressure. Then 3/8", then 5'8". It drills easier if you have some material to remove. If the progressively larger drill is too close in size to the one you're enlarging, it hangs terribly.
Most buckets are only 1/8" to 3/16" thick on the side. That one is a monster!

 

[BXpanded]

I was figuring on a couple of pilot holes, but it looks like I need to go online to get a 5/8 drill. I think I'll ask Harry is 5/8 is REQUIRED because if I'm not finding reduced shank bits I bet others aren't either.

The bolts aren't under much stress because of the way the Piranha captures the edge. I think a good tight 1/2" would probably work, but I haven't tried it (Disclaimer)
Harry

 

[sal64]

i looked it still looks like .790 to me few thousance from .800

 

[kennyd]

I would use a hole saw, at very low speed with plenty of oil.

 

[jmc]

i looked it still looks like .790 to me few thousance from .800

Yeah, that caliper dial is slightly out of sync with the caliper scale. If the thickness were really .890, the scale would be crowding .9.

 

[Coyote machine]

I agree the dial is not properly zeroed.
I'd take it to a welder and have him blast some holes with a torch- DONE!:thumbsup:

 

[ustmd]

I hope your drill motor has a handle extending from the side...when those larger bits break through, there will be substantial twisting of the drill motor:listen:.

Let me double up on that one....I learned that one the hard way drilling through some metal.




The orthopedist told me that this type of fracture is actually very common when drilling by hand in metal and the drill binds....Only took 8 weeks of physical therapy.....

 

[xring100]

I've found the Cobalt drill bits stay sharp at least 3 or 4 times longer than the standard titanium coated ones. I had to drill something like 13 holes for the cutting edge on my bucket the factory edge is hardened steel. I pretty much wore out 1 brand new dewalt titanium in 3 got partway through the 4 hole and then switched to the home depot brand cobalt bits and finished all of the holes on this same bit. Remember Going slow and using cutting fluid are two of your friends. I drilled a 3/16" pilot hole first

 

[Baby Grand]

Domestic HSS or cobalt. Pilot 1/8" & work up, roughly doubling diameters.
Use lots of oil. The hard stays hard and the soft stays soft.
Heat is your enemy.
A slowly turning bit, making a steady chip, absorbs very little heat - most will go into the chip & oil.
A fast spinning bit that isn't taking a good bite and isn't making chips, but sliding a lot will heat up quickly and so will the work piece.
This can result in hardening of the work piece and softening of the bit.
That's when all the cussin' starts.

 

[Teikas Dad]

I guess I completely screwed up when I installed mine.....I used a step drill and it worked fine. Just squirted some WD40 on the bit every once in a while and drilled two holes.

 

[Coyote machine]

My tractor dealer uses a magnetic drill press to drill holes like what you need- in seconds! It's pretty impressive.
Try a local machine shop.