Thread: Rotary Hammer Drill

theres been a bit of a discussion about these. the system is called SDS plus. They are a fantastic drill compared to the normal hammer drills available. I bought the GMC version for $109.00 and it came with a bonus 15 peice drill bit set worth $60.00

The Dynalink ones are also cool. Check out the Dynalink 4 piece Chisel set for $19.00

Glen, isn't it SDS max?
My Ramset hammer drill bits are called SDS max, is there a different SDS ?
( bit's shank are some 19 mm thick. )

$109 you can't go wrong, I think I paid $1100 for mine. (

QLD trade tools have a deal on a box of drill bits & chisels to suit SDS machines cheap . cant remember the price but several of us baught the dynalink machine from bunnings for $100 & then baught the drill bet set from trade tools. Save that money on the first time you don't hire one.
cheers

Marc, theres sds plus and sds max. sds max it a larger version commonly found on ramset and larger machines. sds plus are the smaller of the two and are common to hilti,metabo,dewalt and makita to name a few.

I see, that makes sense.
I didn't think I could buy two drill bits for the Ramset drill with $100

The funny ended bits are usually called hammer drill bits. The slots are called keys, and they are designed like this to lock into the tool holder. Becuase they are held in so strongly, the drill can hammer on the bit much harder than you could with a normal straight shank masonry drill bit. This in turn allows you to drill the hole much faster than you otherwise could.

When you drill with a normal stright shank bit, it's the grinding action of the head on concrete that makes the hole - you grind it up and you need to lean to get it done any quicker. Hammer drills are much more efficient - the hammering chips the concrete instead of grinding it and it goes much, much faster without the need to lean on the tool at all. The air hammer drills are fastest of them all - you can tell it's an air hammer drill by the distinct hammering sound, as opposed to the high pitchy, earsplitting whine of a revved up percussion hammer drill =)

The SDS plus design has been around for about 15 years now. The main SDS plus system is Bosch. There are many companies that design their own version of SDS plus - for example there is a Hilti brand, a Joran brand, a Bordo brand. They are all SDS plus but marketed by different companies with some small changes here and there.

The SDS max design has also been around for 15 years, but this is a much more heavy duty system with a thicker shank, designed for use in larger tools. It has 5 or 6 keys for purchase in the tool holder, and takes some spectacular pounding force. SDS max bits start at around 16mm and go up to around 40mm.

Ramset has a new design, the R-drive. It fits all SDS-plus tools with a few changes. The main changes are in the cutting tip and spiral and these bits are rated the fastest drilling on the market by 25% and the longest lasting. Of course if you are in the habit of snapping your bits in half, they are expensive.

Hilti also has a custom design on one of their drills, the SDS top. This doesn't take anything but the SDS top bit.

The price of the hammer drills goes up according to how fast they can drill the size holes they are designed to do. If time is not an issue to you, then you buy something resonable and cheap to get the job done. If you are paying someone $40 an hour, then you buy the fastest you can get becuase they pay for themselves in next to no time - actually making you money.

Hope that helps

Wow ... thank you Silvia, where did you learned all that?

Talking about hammer drill versus percussion, I noticed that when I drill a 10mm hole in brick with my green Bosh that has a barley adequate wrrrrrrrrr system, I get a 10mm hole (after some pushing all right) and no trouble in fitting a plastic plug in it. When I drill using my Hitachi hammer drill, (bang bang system), it is so much easier and faster but ... I get a 11 or 12mm hole with a 10mm bit and no chance to fit a plug that holds anything at all. I discovered this the hard way after achieving 3 good holds out of 10 and after exhausting my repertoire of insults to Ramset plugs, I finally realised the problem and now I use 9mm bit for a 10mm plug.
I never used the Ramset hammer for drilling as I bought it to demolish a double brick retaining wall, that was built to resist a catapult attack. It certainly made a small job of those bricks...

Marc

a couple of things.
just cause it can go bang bang bang does not mean it should do it flat out on a small hole like that. Slow and steady gets it done.
Some brick are a bit soft too.
lastly you can get some good double cut heads for the sds+ and they work a treat to.

Hagrid

The Hitachy drill I am talking about is not a big one, ins size just about the same as the bosh...and I think the bits are called Dynalink.

I get your point and I did try every different way, even not pushing at all, to no avail. The bricks where actualy very hard even when hollow but I think the drill is just too much. I must admit that it drills into concrete as you would push a stick in the sand.

Another thing is that the Ramset Plugs are not the best. I know Hilti makes some mean plugs special for bricks but I can't find a place that sells them around here.
PS
What is double cut head?

There have been many explanations about what SDS stands for.
My favourite, and easily remembered, is Slotted Drive System.
For chiselling you need a drill with rotary stop so just the hammer action is used.

If you remember, an air hammer drill works by striking the concrete, chipping it up. As someone correctly said, brick is soft, much softer than concrete. The force used to correctly drill a 10mm hole in concrete is too much to correctly drill a 10mm hole in brick. The strike tends to crack the brick and blow the back out of the hole. This leaves you with about 1-2mm of 10mm hole in the front, then a big flareout towards the back where the brick has cracked away.

Nylon anchors and ramplugs work by gripping inside the walls of the hole - that's what the little fins are for - to stop the plug spinning while you drive the screw through. If there is only 1-2mm of 10mm hole left, the fins are in empty air and the plug becomes loose with nothing to hold onto.

Air hammer drills usually have an option to 'drill only' rather than hammer drill - this is the correct setting for brick. Like a normal straight shank masonry drill bit, this makes the bit grind into the brick instead of striking it. You get the correct 10mm hole all the way through the brick instead of cracking and blowing the inside away. It takes longer but works better - 'make haste slowly'.

For the random information buffs, the actual meaning of SDS is 'Silver & Deming Shank' - easy to remember isn't it!

Sil =)

G'day All.
I went and looked at the Dynalink Drill. I decided to let the moths out of the wallet and spring the extra dollars for the GMC drill with the extra bits and chisels.
I drilled some 10mm holes in the edge of my shed slab for starter bars.
The GMC went through the concrete like **** thru a Goose.

I love it.

After pouring the driveway edging. I needed to chip a bit of overpour away to remove the form work. The GMC on hammer only with the pointy chisel made short work of it.
My neighbour bought the Dynalink drill a week before I did. He has the royal ***** now after seeing the GMC with all the extras.

Hooroo
Regards, Trevor
Grafton

They are an awsome tool for the cost. The extras you get are worth the $109.00 alone

I now look for jobs i can "use" my new toy on. I took it to work to hang an overhead cupboard using 6mm nylon 'knock-in' type anchors and it drilled into concrete slab walls with little effort from me. Overhead was up in no time,Lots of concrete dust thru the office to boot.

it could have used 4 anchors but i went the extra two just in case.

This is the second drill, i took the first one back after a gearbox issue,The return policy is second to none. No questions asked. And i am still rapt in the product and for the company too for that matter. I would not hesitate to buy another GMC. And i was a true Makita man when i was on the tools full time.

Like anything, Care and Respect will get you a lifetime i feel.

Hello all. I'd like to add my Fathers day tale in here. My son entered and won second prize in the Capalaba stores colouring competition. $100 voucher. So mine cost me a total of $9. Happy father and happy son.