what is a magnetic drill

[wallopadonkey]

it may sound stupid but i dont get it are they like a pillar drill or summit?

 

[fingers99]

Sort of. The idea is that the drill itself is mounted on the section you're drilling with by a magnet (which can be switched off, thather like the magnetic bases for dial guages and such). So, think of it as a take to the workpeice pillar drill.

 

[Paul.]

Its a drill with an electro-magnetic base, Like this one

 

[wallopadonkey]

so is the magnet just for holding the work piece or will it drag the drill down into the metal to apply pressure?

 

[wallopadonkey]

and if so why not just use a pillar drill?

sorry bout all the questions i get like it when consuming too much red wine

 

[Paul.]

No it just holds the body of the drill onto the work piece ,then you feed it like a pillar drill, Why not us a pillar drill?, try drilling a one ton beam or plate on a pillar drill, or working in awkward positions, these things will even work upside down

 

[wallopadonkey]

paul why do people say 'use a mag drill it will do that easy ' would a pillar drill not do the same?

 

[Welderpaul]

Mag drills tend to be used on site, or as Paul says, in awkward positions. I used one last week, ten storeys up, on a scaffold, drilling 25mm dia holes through a beam. I wasnt going to get the pillar drill up there! Even in the workshop, its often easier to take the drill to the workpiece rather than the otherway round, particularly with the big stuff

 

[scarecrow]

Magnetic drills use broach cutters which basically cut a bit like a hole saw leaving the bit in the middle to just drop out. a twisted bit has the cut out the whole hole broach cutters are much quicker at cutting large diameter holes

 

[Hitch]

Differnt type of cutter aswell....mag drills generally take broaching or annular cutters, work a bit like a hole saw.

Some of the bigger ones will take taper shank drills, tapping heads etc.
Portability is key, they work at any angle, any height....

 

[Pete.]

One of our guys forgot (din't know) to tether ours last week and someone pulled the plug from the site transformer. Luckily it missed his leg but it made a right mess of the drill.

 

[Marty2005]

So, if you're limited for space in your home workshop, instead of having a permanently mounted pillar drill, just get out the magnetic drill and plonk it on top of your steel topped welding bench. Make sense? Or would a pillar drill have distinct advantages over a magnetic one?

 

[Wedg1e]

So, if you're limited for space in your home workshop, instead of having a permanently mounted pillar drill, just get out the magnetic drill and plonk it on top of your steel topped welding bench. Make sense? Or would a pillar drill have distinct advantages over a magnetic one?

Fine, as long as whatever you're drilling will fit between the drill and the bench
A floor-standing pillar drill might have 4 foot capacity!

 

[Wozzaaah]

One huge advantage of a mag drill over a pillar drill is that the annular cutters don't require any pilot drilling, just a centre punch mark for the pilot pin to sit in.
Mine is this one, it is capable of drilling a 50mm diameter hole in 50mm thick steel in one pass!

 

[BillJ]

One huge advantage of a mag drill over a pillar drill is that the annular cutters don't require any pilot drilling, just a centre punch mark for the pilot pin to sit in.

Couldn't you use the same type of cutter in a pillar drill?

 

[Hitch]

You can Bill, but need an arbour, most small pillar drill wont accept taper shank drills/arbours. Also needs to be ridgid aswell, or it becomes easy to break the cutter.

 

[Welderpaul]

I have a 3MT taper arbour to suit mag drill bits if anyone needs one?

 

[Wozzaaah]

There's morse taper blanks on ebay for pennies but the problem with them is there's no spring to help centre the pin and eject the slug. Not sure about ready made ones, used to see a few on the but not at the mo.
Mind you, I doubt it's rocket science to fit some sort of spring inside it .

 

[chevyman_de]

At less than 30 quid incl. shipping for the right tool (when Paul's arbor is no longer available) I wouldn't mind manufacturing an arbor on my own. Has to be precision made after all.
But as said before, you'll need a strong, rigid and slow running pillar drill for annular cutters.