drill bit saw thing

[Wallace]

Chain drilling with a cone cutter......

 

[BrokenBiker]

Chain drilling with a cone cutter......

that's nothing, when I was in college we had to make a part that was basically a square in a square. basically needed to be able to hold itself in place but push out easily. had to chain drill to get the square hole, not allowed to machine it on the mill. anyway one kid started about 6 months after us and to help him catch up they said he could use the mill. unfortunately he asked one of the lads to show him what he needed to do, and not wanting to help him do the job easier than we had to, told him to chain drill it with a 6mm slot drill...

it wasn't until he had about 3 holes left to drill the tutor came out and asked why he didn't just drill a large dia hole then mill the corners out...

 

[penfold]

yeah, my father thought that was a bargain, took about an hour before it went pop

Take it/send it back and get another; Didldidi are very good when it comes to that kind of thing.

 

[steviec_lj]

What material did you use them on? I just dug my set out and the packet says 'Suitable for wood and plastic'. I can see aluminium swarf on the largest one which reminded me it was used recently to hog out some 3mm alloy and save a bit of file time.

I've used them on a variety of materials.

Steel, they just warm up and do sweet FA.
Alu, they just warm up and maybe think about removing some material.
Plastic, they like to remove what ever material they think needs removing, not what you want.
Wood, they don't do a bloody thing.

Tried them in a pillar drill, battery drill and full on corded power drill. If they had thought them out a little better, or not even bothered then the concept would have been brilliant. Unfortunately, I now stick to a router for wood and plastic, extremely noisy, but it works and its reliable.

 

[brightspark]

At that rate you could rent one cheaper! Anyway,I thought electricians lived and died by using a cone cutter for everything?

nahhh i get off on using starret hole saws and garryson carbide burrs. conecutters wear out 2 quick and cost a packet. well the halls ones do

 

[BrokenBiker]

nahhh i get off on using starret hole saws and garryson carbide burrs. conecutters wear out 2 quick and cost a packet

I have a 12-30 (I think) step drill that has seen some abuse and still cuts fine, mind you it does get a healthy coat of trefolex every use

 

[Robotstar5]

Anyway,I thought electricians lived and died by using a cone cutter for everything?

They have their uses in the right place, I usually use holesaws but have used the stepdrill to open up 20mm holes to 25mm in glandplates as it's quicker than fixing something behind the hole to centre the holesaw.