Using SDS drills with a PDC Drill

[Woodentop2]

Why isn’t there a converter to plug SDS drill into a quick fix type chuck. There is a a converter the other way to convert the SDS drill type to using a quick fix connector.
Why not the opposite way.

 

[six-point socket II]

Hi,

The short answer is it wouldn't make much (if any) sense.

Using a rotary hammer in drill mode (without hammering) and having a jacobs chuck to hold regular/ non SDS-plus drill bits for it, is a neat feature on quite a couple of occasions. The same goes for that SDS-plus fast fix adaptor.

Using SDS-plus drill bits in a percussion or regular drill doesn't make much sense:

SDS-plus drill bits are designed to work with, and withstand, the power of a rotary hammer. They're focus is on hammering into the material and using the coil/helix to transport off the debris.

A percussion drill doesn't generate enough force for effective (hammer) drilling with SDS-plus drill bits. And the SDS-plus drill bits are simply not the best cutters when used in drill only mode. Additionally their shaft design allows for quite a bit of movement (hammer action) that you wouldn't want to have with a regular drill.

Here's a video I made and have posted before, but I think it shows the different methods of drilling quite well.
https://vimeo.com/223792962

Kind regards,
Oliver

 

[Rip Van Winkle]

Hammer drills and rotary hammers work differently.

SDS drill chucks actually hold the SDS bits loosely so the bits can slide forward and backward in parallel with the chuck. This is because on Rotary hammers the chuck holds and spins the bit, while a separate hammer impacts the flat on the back of the bit from inside the chuck at a high rate of hits per second.

Hammer drills on the other hand, hold the bit securely in the three jaw chuck, and the whole chuck and drill bit are rotated and hammered together.

In general, the independant nature of the two actions makes rotary hammer mechanisms more durable, and more efficient for some materials, but also heavier and more expensive and more complex.

It is possible to get an SDS adapter that can be locked into a drill chuck to quickly change SDS bits, but I’m not sure whether you would gain any advantages in efficiency otherwise.

Festool could probably manufacture a Centrotec SDS adapter for the PDC, but I am guessing they may not want to confuse customers with a lack of performance, or they figure they wouldn’t sell enough. 

 

[AlexThePalex]

I can think of many reasons why this doesn't exist.

• It would be a very long extra drill chuck, making it an awkward and unergonomic experience working with the drill.
  
• It would also be very expensive, with such an elaborate mechanism on-board. Think in the $300-400 range.
  
• It is very doubtfull it would have much force since it is not connected directly to the drills' motor but through a gear train.
  
• It would probably destroy your drill, which is not designed for the hammer forces generated.