Best Masonry Drill Bits for Combi Drill

[Moley]

Mine are silk.

I didn't realist you could get silk masonry drills.

 

[telectrix]

what's wrong with one of these?

 

[rsgaz]

Black and Decker Pro Line

The Bullet ones are even better. Used without percussion, will even do hard red brick.

 

[Rpa07]

A lot of the time, it's not the bit that's the problem, it's the machine. Straight shank masonry bits are obviously used in machines with 3-jaw chucks. To the majority of users that means a combi drill. The impact energy of combi drills is vastly inferior to SDS machines.
On a combi drill, it's a percussion function where the chuck moves backwards and forwards on a cam.
With an SDS machine there is actually a piston that is fired forward onto the end of the drill repeatedly to provide the hammer action. that is why you shouldn't lean on an SDS machine because you are actually suppressing that piston.
With heavier duty masonry (engineering brick etc.) only the higher impact energy of an SDS machine will do. Using a straight shank in a combi with the lower energy percussion function causes a lack of progress, this leads to a huge heat build up. On cheaper drill bits this can actually melt the braze that fastens the tungsten carbide tip into the end of the drill or even disintegration of the tip itself.
The more professional drill bits have a better grade of carbide tip and a higher melting point braze but in some masonry even they won't do.
SDS masonry bits (when drilling in hard materials) should be considered as rotating chisels rather than cutting bits. It chisels, turns slightly, chisels again, turns slightly and so on until a hole is formed. With a straight shank in a combi there is not enough impact energy generated to do the chiselling efficiently.

I had that exact conversation in my head yesterday whilst driving. You’ve confirmed everything my wandering brain told me. Cheers Billy

 

[Bellendian]

Bottom line...ditch the combi and get a battery SDS and impact driver. Only use the combi for holesaws really these days.