Hi Everyone,

I'm in the market for a drill - and hoping to draw your bolting experience, particularly with respect to drill characteristics.

Background: I'm looking to bolt some multi-pitch limestone near to where I'm currrently living ... but first I need to get hold of a drill. Also looking at improving the local anchors.
Note: This question is about drill performance - not access, permission or safe bolting procedure (all of which are important in their own right).

Voltage:
36V drills are beefier (RW called them "rockmunchers"), but heavier and more expensive than 24V drills. How much time, pain and sweat do the 36V drills save? Is the extra weight and cash worth it?

Batteries:
Lithium-ion batteries get poor online reviews for cordless drills. NiMH hold more energy (3.0 Ah) than NiCd (2.2 Ah) ; but NiCd are cheaper and allow high discharge rates.
- Is the discharge rate a factor when drilling rock?
- Do Li-ion batteries deserve their bad name?
- How are NiCd batteries in summer heat with direct sun?
- What batteries do you use?

Brands:
Bosch / Hilti / DeWalt / Makita / Panasonic ??

Any other comments? Looking forward to hearing your experience.

Links to related threads:
What drill to buy?
What drill ?
Drills ???

I got a 36V for drilling into hard Sandstone/Quartzite.

You're drilling into Limestone which I imagine will be a lot softer.
So I reckon a 24V will be fine (best chat to someone who has drilled both types of rock).

_________________
Climb ZA - Administrator

Not to hijack, but what area are you currently living in? Need some help?

Dude,

After exhaustive research (yes, I must get out more!.........but now I do............bolting!!)......

I recently bought the Bosch GBH 36 V-LI Professional

You can find it here:

http://www.bosch-pt.co.za/boptocs2-za/Trade+and+Industry/Tools/ZA/en/gw/Cordless+Rotary+Hammers/101308/GBH+36+V-LI/9763/index.htm

With two battery packs included it cost me R8100.

The Hilti alternative (the TE 7A) - 36V and with only one battery pack was a whopping 14 grand!



http://www.hilti.co.za/holza/page/module/product/prca_catnavigation.jsf?lang=en&nodeId=-233819

Now it's only fair to say that most bolters who buy Hilti seem to buy the TE 2A and, with one battery, it's a more reasonable 8 grand, but the TE 2A compared with the Bosch is:

-- only 24V instead of 36V
-- only 400W instead of 600W
-- NiCd or NiMh batteries available but no Li-ion as in the Bosch (see battery notes below)
-- only 4-10mm drilling range instead of 4-26mm
-- only 1x 2Ah battery pack against 2x 2.6Ah packs

Plus the Bosch comes with a very useful and accurate battery-life indicator, a depth stop and a chisel function for those Mount Rushmore moments!

The Bosch is lighter than the equivalent Hilti (TE 7A) and 400g heavier than the TE 2A



Batteries:

All my research shows that lithium ion batteries are the very best for this sort of application. It's no surprise that Bosch and Hilti use Li-ion in their most powerful drills.

-- These batteries have very little memory,
-- They can be recharged at any state of existing charge,
-- They have the highest energy density of the three you mention -- that's more power for the same weight, or equal power with lighter weight, however you want to look at it
-- When not used, they discharge very slowly, unlike the others

all the stuff on Li-ion is here:

http://www.howstuffworks.com/lithium-ion-battery.htm

There's a lot more if you want to check it yourself.


Conclusion:

I reckon the Bosch is the best out there at the moment for performance and value for money.
and no, I don't have shares in the company!!

I've used mine for eight months now, drilled approx 200 holes and it's just what I wanted.
It drills an 80mm hole in hard quartzite in 20 seconds, does about 15 holes on one battery pack.
The weight is fine. It's not the lightest drill but it's incredibly powerful and a great training aid. I'm getting stronger!

I can't complain really!

Happy hunting




P.S. Makita et al. -- forget it!

@Justin

I'm expecting limestone to be soft ... but you never know. Would be great to hear people's experience drilling CaCO3 (Jimbo, Scott?)

PS - How are your Li-ion batteries holding up?

@pierre

The more the merrier. Looking to use up your voyager miles? ;

I agree whole heartedly with Tapster. I bought the bosch on Justin's advice and have not regretted it for a minute. If you are drilling Limestone near the sea you are going to want to be putting in glue ins and for that you need 12mm holes and the bosch is the business for that size hole. I have drilled about 100 12mm holes for ARF with the bosch after struggling with the TE2A for 12mm holes. I have probably drilled another 30 or so 12mm holes and way over 100 10mm holes and the drill really does munch rock!

For 10mm holes a TE2A is just adequate. I did about 40 12mm holes with it and as mentioned it was a struggle and you use way more drill bits as the bosch has nearly twice the impact energy as the te2a. That said I have probably drilled over 200 10mm holes with the te2a

France? Croatia? Italy?

Have 2 drills...yes I need both.

The 36V Hilti is the real bomb. Drill speed & impact makes a difftence to how many bits.

The Matabo 18V(yes SDS) is really light & sweet to use. Li Lion bat. Really not bad. Drilled a bunch of holes with it in hard rock. In lime stone this would be perfect.

I have two drills... and I definitely need them both as I have worn out four others over 20 years of bolting. At present I have 36V versions of both the Bosch GBH 36 and the Hilti TE 6A and would rate the Bosch over the Hilti. It drills like a fiend - so much so that you should wear eye protection from flying rock shards when you start the hole - I am not joking!

I picked up the Bosh on E-bay while on a trip to the UK - almost brand new with an extra battery for R2200 - deal of the century....

Wow!
Holy WOW!

To Babycoat - my batteries are hold up fine - I heard of someone tumbling their battery 200's down a face and is still using it today.

_________________
Climb ZA - Administrator

One more vote for the Bosch GBH 36

Anyone know where I can pick up a 24V drill? Been looking but most of them seemed to have been discontinued..
Anyone of these.
Ramset
Makita
Bosch
Metabo

I've always been a hilti fan ... that big red suitcase it comes in does it for me but never tried bosch cordless, looks a bunch cheaper for starters - http://www.marlintools.co.za/Specials.asp

_________________
Gustav
Roc 'n Rope Adventures
Waterval Boven
013 257 0363
rocrope dot com

Yeah Hilti is a little out of my price range atm Didn't spot any 24V drills on their site but will give them a call.