Drill bits

[m4tty]

Hi,

I have been given a 24v dewalt sds drill and have only used hammer drills before.

I wanted to know what is the most commonly used drill size as in the longer drill bits ie, 400-600mm in length. As I want to get one bit which can be used for most jobs ie, a 20mm bit.

I know I'm not that good at explaining so any pointers would be appreciated

cheers

Matt

 

[Theorysparky]

Matty

i have 8mm,10mm 16mm, 20mm, 25mm

reason being if i need to drill through for a large hole i can start small and increase to the required size.

less strain on the drill an minimises blow out of bricks

 

[Apache]

The cheapest option is to buy a set. Are you normally working on modern houses? If so a 400mm should bridge the cavity. Round here my walls are 800-900mm thick so you need a meter drill bit!

Theory is 100% correct, drill small then go larger. If you drill through 8mm you can drill through the brick from both sides using you 20mm and save breakout.

 

[Megaohm7]

Hi M4atty.

The sds drill will not require the sort of pressure as with a hammer drill whilst drilling most building materials. But as been said before start with a small hole and build up to the required size to minimise damage to brickwork etc.

The dewalt 24v sds is a good piece of kit, the one I use is a bit battered now but is still going strong

 

[Theorysparky]

i had a 24v makita until it was knicked

did the job no probs

 

[nwilliamson45]

Mattyi have 8mm,10mm 16mm, 20mm, 25mm

reason being if i need to drill through for a large hole i can start small and increase to the required size.

less strain on the drill an minimises blow out of bricks

Hi,

Every now and then Aldi do a full set for

 

[ianmacd]

Do not skimp on drill bits as its false economy. I use dewalts extreme 2 range.

 

[Andy™]

in my bag i keep a 12 & 16mm 450mm long SDS. in van i have 8-25 in 450mm, and a few 1mtr.

along with various smaller

 

[m4tty]

Do not skimp on drill bits as its false economy. I use dewalts extreme 2 range.

Screwfix are doing a set of 10 dewalt sds extreme 2 for

 

[steptoe]

Hi,Every now and then Aldi do a full set for

 

[PC Electrics]

The Erbauer range at Screwfix are good. I have 10, 12, 14, 16, 18, 20, 22 and 25mm sizes. They all get used.

Don't push in too hard with your new toy, let the drill do the work.

 

[initforthemoney]

All this talk of stepping up in drill sizes is a little misleading.

The reason being, is the way an sds bit works, it would jam on the edge of the hole and therefore activate the clutch.

Plus most of the time, pilot holes are only good to see where you will end up.

Even then, putting a pilot through and then a larger bit is a bit hit and miss as the hammer will force its way through if you go a little off course.

Just measure up and line it up properly and go through once with the right size bit.

 

[Andy™]

have to agree with init. no point in smaller holes than larger. just drill the size you need first time

 

[ianmacd]

All this talk of stepping up in drill sizes is a little misleading.The reason being, is the way and sds but works, it would jam on the edge of the hole and therefore activate the clutch.

Plus most of the time, pilot holes are only good to see where you will end up.

Even then, putting a pilot through and then a larger bit is a bit hit and miss as the hammer will force its way through if you go a little off course.

Just measure up and line it up properly and go through once with the right size bit.

I disagree there as going though once is almost guaranteed to blow something so if drilling outside in, then some re-plaster work is needed and if going inside out then you may have just compromised the weather face of the block work.

 

[Apache]

I'm with Ian here. No point drilling 8mm then 10mm then 12mm but if you go through 12mm and then 20 there is definitely less breakout and no jamming issues as the hole sufficiently small to be the path of least resistance yet there is still plenty of work for it to do.

 

[batty]

I think it all depends what your driling through as to whether it will blow out, as for using a smaller drill that will not always stop it. Personally I would rather drill out to in if possible. plumbers always drill out and ruin the builders brickwork and on quite a few jobs they have been charged to put the brickwork right.

 

[ianmacd]

Depends on the drill too. More hammer force, the more face you will blow off. If drilling in one go you would be better using a 'smaller' hammer drill, it will take longer but should cause less damage on the other side.

 

[initforthemoney]

Yes, inside out is the better way.

Alternatively, once you have drilled a few, you can hammer through inside and most of the outside.

Then switch off hammer and gentle pressure will see the rest through with virtually no break out.

 

[tom1]

plumber

and

ntl.

 

[user 6351]

I have a