A better SDS drill bit to drill out those 5-piece sleeves and cones?

Has anyone else tried the new Bosch Xtreme SDS bits? The tip is all-carbide, bonded by some voodoo magic to the fluting part of the bit. It's also shaped differently with more rounded edges that don't catch and bind in the usual way. So far, we're finding that they happily drill out the cones and sleeves of 3/8" 5-piece bolts.

Binding still happens but seems less sudden, there's more warning. The only caveat is it's worth spending a bit more time regularly extracting the bit and cleaning out the hole using brush and fishing around with the magnet.

I'd like to hear some more feedback from others. Anyone?

Rusty 3/8 5-piece bolts are hard to remove, techniques complicated to learn and teach, but if we can abandon the entire tap/die/draw-stud/etc shenanigans, 5-piece removal becomes as quick and easy as wedge-bolt removal.

  boschtools.com/us/en/boscht…

Not relevant to drilling out metal (which they seemed to be optimized for) but I've been using them on and off in really hard rock after finding a pack of 25 for dirt cheap. They're not significantly better than the lower grade bits for drilling (maybe get 10 to 15% more holes per bit). The main benefit is that the head diameter doesn't change when they start wearing off, unlike the standard "arrow-head" SDS bits with the carbide extending a bit to the side. These tend to get a bit skinnier with wear and make it harder to hammer in the bolt.

They are great bits for sure, starting using them a few years ago while drilling in quartzite, much longer lifespan. 

Are you using a 3/8" bit to drill out the sleeve & cone or are you using a 1/2" bit to enlarge the hole while drilling out the sleeve & cone?

1/2" new hole, 3/8" old bolt.

Thanks for the information. Recently when replacing a 3/8 plated wedge bolt the sleeve of the wedge stayed in the hole when I extracted the wedge bolt, and I was able to drill this sleeve out using a 1/2” regular SDS bit. 

"Are you using a 3/8" bit to drill out the sleeve & cone or are you using a 1/2" bit to enlarge the hole while drilling out the sleeve & cone?"

What Greg said. Old 3/8 bolt, new 1/2" SDS Bosch Xtreme bit in hammer/drill mode.

There is another method for removing the metal sleeve parts with a 3/8" steel bit, without hammer mode, just drill mode. This is slow. In my experience, the bit heats up fast and wears out quickly. Plus this requires a bulky chuck adapter for using the non-SDS bit with a rotary hammer.

This is great beta, Thanks!

Have you compared the 3/8" with the 1/2" in these new bits? With other SDS designs, I prefer 3/8" as it is often possible to fish the metal out of the hole with the bit before expanding it to 1/2".

I picked up a couple of these bits to see if I could get more life in hard rock, was only getting around 7 holes before the old two carbide bits was already making holes too undersized for the cone. I have another couple routes to replace soon and could give this method a try.

How much longer are you seeing drilling through the sleeve/cone typically than if you had extracted the sleeve and were only going through rock? Just wondering if there is any battery penalty.

The ASCA has been using them for many years, starting maybe 10 years ago with the 3/8" bits (which are less likely to bind when expanding 1/4" holes with a hand drill). I think the 1/2" ones bind less when expanding 3/8" holes as well, but that is highly dependent on rock type, drill, how hard you push on the power drill, etc. You can find good deals on the bulk packs and they've become our standard drill bit in most of the sizes that we regularly send out (we have them in 3/8", 1/2" short, 1/2" long, 5/8").

For those interested in this sort of technique, I would not suggest power drilling through 3/8" 5-piece sleeves in anything but bomber rock unless you are going to replace with glue-ins. The reason is that the sleeve and cone pieces tend to wallow out the hole in medium to lower quality rock. Also these pieces can get "welded" to the sides of the hole and they can stay in the hole even with magnets, hooks, etc - actually that can happen even in good quality rock, but in good rock it's usually possible to scrape them off with hooks and magnets.

Thanks Greg that's helpful. It makes sense how these might wallow out the hole as they plow through the sleeve and cone. Probably best used with glue-ins.

Yeah that's why I sometimes use the 3/8" bits to drill through sleeves/cones in good rock, once you get the sleeves and cone drilled out, you can check with a magnet to make sure you got everything. Then go to 1/2" drill bits. We did that on an entire 10-bolt pitch in Boulder Canyon a few years ago, all the old bolts were really long (4"). Worked, but it was murder on batteries. You definitely need a hand drill or a big vise-grips and you need to swap to those immediately if the drill bit binds too much to get out with the power drill. It's probably possible to get the bit irretrievably stuck using this method, so you need to be careful!

FYI - it was this route, which we replaced because one of the anchor hangers was a sketchy old aluminum hanger: https://www.mountainproject.com/route/105748274/thats-weak