Step drills, what brand?

[woodchucker]

Step bits are great for sheet metal, but also plastics. They don't grab and destroy the plastic. Just another FYI good use for them. And rather than go out and buy plastic drill bit, use a step drill.. also great for brass.

 

[MetalMuncher]

Step drills also take care of deburring the hole, and can be used to de-burr the back side of the hole in parts that can be flipped over. I buy the HF sets when they are on sale, and keep spare sets for when one of them breaks. Very handy tool!

 

[EmilioG]

Can you use RotaBroaches to cut holes in thick aluminum, say 1/2" thk.? Do the RB cut over or under? I see on the Hougen website that they have a step drill and Industrial annular cutters for deep holes. I'll email Hougen tech support. I'm interested in a replacing a few of my Lenox hole saws.

 

[mikey]

Can you use RotaBroaches to cut holes in thick aluminum, say 1/2" thk.? Do the RB cut over or under? I see on the Hougen website that they have a step drill and Industrial annular cutters for deep holes. I'll email Hougen tech support. I'm interested in a replacing a few of my Lenox hole saws.

Hougen and Blair sell rotabroaches that will easily drill 1/2" plate. They're the type that has its own stem that is held in a chuck or collet. Try one and see how you like it - I'm sold.

 

[EmilioG]

Yep. I looked them up. Hougen will be my choice in 3/4". 1" DOC if I choose to use it in an R8 round collet, in a mill. The shank is short, and I'd be worried about the cutter shifting sideways.
The proper arbor for these cutters is definitely the way to go.

 

[darkzero]

I've seen rotabroaches that can go 6" deep. Maybe the there's even deeper but I never looked. I've got my eye on a 2" diam, 2" or 3" depth of cut rotabroach. Just have pulled the trigger yet.

 

[FOMOGO]

Bob, I've used the rotabroaches in hand held drills on truck frames and the like with no issues. Mike

 

[mikey]

Just an aside, stick wax lube is recommended for use with these rotabroaches and it works well.

 

[Downunder Bob]

I have had a cheap one that I bought 10 or 15 years ago, I didn't use it that often until last week when I needed to drill different size holes on a small sheet of( 20Ga) Mild steel,the step drill worked really well.

I'd like to to buy a decent size one like 1/4" to 1.1/4" for the shop for those rare occasions when nothing else works as fast or as cleanly as a well made ,good quality step drill.

Now Viking seems to be well made but (@ $140(set of 3) it is way too expensive for my hobby /occasional use.

what manufacturer comes to your mind when you shop for step drills?

G'day Ken, if you need to drill a number of holes of the same size in sheet metal, there is a technique to grind a regular twist drill so that it will drill very neat round holes in sheet metal, these bits are also very useful in plastic, rubber, brass, copper and other difficult to drill materials.

Sorry I don't have a picture that I can post, I'll try to describe it, basically you grind the drill so that it has a central spigot that will guide the drill as it cuts, and you grind the normal cutting edge down at a slight angle to be lower near the central guide and the outer corners contact the metal first the drill will resemble a traditional wood bit, but the central guide will not have the thread section on it. Sounds a bit odd. google grinding a drill bit to cut sheet metal. there a quite a few videos on you tube etc.

 

[JimDawson]

Sorry I don't have a picture that I can post, I'll try to describe it, basically you grind the drill so that it has a central spigot that will guide the drill as it cuts, and you grind the normal cutting edge down at a slight angle to be lower near the central guide and the outer corners contact the metal first the drill will resemble a traditional wood bit, but the central guide will not have the thread section on it. Sounds a bit odd. google grinding a drill bit to cut sheet metal. there a quite a few videos on you tube etc.

Are you talking about a brad point bit?