Drilling through 3/8" RAWL?

When rebolting, can one pull the shaft of a 3/8" RAWL 5 piece (plated usually), and with a 1/2" bit and Bosch, drill straight through the old sleeve and cone? Thus creating the 1/2" hole for your glue in or whatever. 

The picture below is of a 1/2" RAWL 5 piece, but if it were a 3/8", this would be the stage I'm talking about just drilling everything out and boring to the new diameter.

I have yet to try it, but it would be very applicable to our area and save a lot of time...

Taylor Spiegelberg wrote:

When rebolting, can one pull the shaft of a 3/8" RAWL 5 piece (plated usually), and with a 1/2" bit and Bosch, drill straight through the old sleeve and cone? Thus creating the 1/2" hole for your glue in or whatever. 

The picture below is of a 1/2" RAWL 5 piece, but if it were a 3/8", this would be the stage I'm talking about just drilling everything out and boring to the new diameter.

I have yet to try it, but it would be very applicable to our area and save a lot of time...

Drilling metal with a hammer drill bit is terrible or worse, you want to run a 3/8" metal bit down first. Usually the sleeve or cone will spin anyway making it impossible to drill.

Jim Titt wrote:

Drilling metal with a hammer drill bit is terrible...

This is true but it works. I've done what the OP is asking about many times. Use an old bit and wear safety glasses. It's also best to place a glue-in instead of a 1/2" wedge anchor. My experience in drilling out 3/8 holes to 1/2" is that the new hole can be slightly irregular. 

I'd give this method a try first:

http://www.safeclimbing.org/education/removingrawlbolts.htm

That said, I save a few of my old bits and have drilled through sleeves and cones.  Go slow, and, pull out the chunks.  Will further trash a worn out bit...so...not sure how many bolts you could drill through.

Greg Barnes recommends getting an SDS bit type that specific to this task:

"Also if you can use power tools, it's fairly easy to simply power drill through the old sleeve and cone - assuming the bolt core does not snap of course (if it does your only option is some sort of core drilling). Just get a 3/8" solid-head carbide SDS bit (lots of manufacturers have them, often advertised as "4X better in rebar", available in big box hardware stores), and drill right through the old sleeve and cone. You'll need to stop and cool the head of the bit fairly often (spit water on it, etc). Once through the old cone/sleeve, then swap the bit (watch out if it's hot!!) for a 1/2" bit, and expand the hole (otherwise there are often pieces of sleeve left in the hole, you can actually get those out pretty easily in granite, but in limestone they're likely to have wallowed out the hole a little bit)."

I'd probably consider that if I had a bunch of nasty stuck 5-piece bolts to deal with.

I think folks have made special extraction tools specific to the job of pulling out those parts as well.

Nice, thanks for the info guys. How come all of these methods seemingly aren't talked about more? All I ever find online is people tapping the sleeves then threading them to get em' out.

It hasn't been talked about much because a lot of people have failed to get it to work with 1/2" bits and lighter weight drills. We used to do it now and then when replacing bolts in Owens River Gorge around 2000 or so, using the old big heavy Hilti TE-6A. The 3/8" drill bit method seems to work even with lighter weight drills, but it takes much longer/more battery power than a heavier duty drill.

There are a few main things to watch out for when drilling through 3/8" sleeves and cones with a 3/8" solid-head SDS bit. It's best to have a bigger, heavier duty 36V drill, not the lightest weight 36V Bosch for instance (which I think they don't even sell anymore?). We managed to do ten 4" long bolts in a row with the light Bosch, then expand the holes to 1/2", but we went through all 4 batteries I had, and most folks don't have that many (this was in granite). If you have a bigger, heavier duty drill it's possible to use 1/2" bits, but make sure to bring extra bits. Also there's a chance that the shards will wallow out the hole so going to glue-ins may be a better call (depending on the rock of course, the shards are less likely to wallow out hard rock).

Warning: it is possible to get the 3/8" drill bit stuck in the hole irretrievably if you are not careful. Wear safety glasses of some sort, you can get little hot shards of metal flying out of the hole.

1) make sure the bolt unscrews completely, if the end snaps off you're hosed. That usually happens where the threads start so it's usually obvious (also you typically feel it snap as you unscrew). Pull the upper sleeve (a small needle nose pliers can be nice).

2) cool the bit frequently as you drill, when I said "spit on it" I should have said "spit a fair bit of water you just sucked from a camelback" but much better is to have a squirt bottle to squirt water on the bit.

3) clean the hole frequently, a magnet on a stick and some sort of hook tool (I use an old bike spoke) is important. 

4) watch out for binding, the drill bit wants to bind (on the sleeves which are getting smashed against the hole wall as you do this). Even if you are watching out, it WILL bind sooner or later. You need to detach the drill and attach a hand drill or something else you can really crank on the bit with (maybe vice grips?). Even then you have to be really careful, you will think you're going to have the drill bit stuck permanently, and it could happen if you're not careful

5) keep an eye on the drill bit tip, it may start disintegrating on you

6) even when you drill through the end of the cone into rock, there are often still shards of metal inside the hole. Try to fish those out with magnet and hook, and it's great to have a flashlight to look for more in there. Usually you can get them all out, but sometimes you won't be able to get them all, and when you drill up to 1/2" they can still be in there - mushed into little shards pressed against the bolt hole wall.

Anyway, it's effective but highly battery intensive. In very soft rock this is not going to work well since the metal shards will wallow out the hole. Which can be OK if you are going up to a glue-in. Also I would keep an eye on the dark grey/reddish (depending on how rusted the sleeve/cone are) debris/water you get out, it could definitely stain white rock like in the photo, you may need even more water to try to wash it off the rock.

Also a good tip is to use a breaker bar when unscrewing the 3/8" 5-piece, it lets you put a lot more slow, controlled power into unscrewing the old bolt. If you use a short wrench you often have to smash it with the heel of your hand, or even whack it with a hammer, to get it to move, and my guess is that increases the chance of the old bolt snapping. A 6-sided wrench (and/or socket) is really important too, you can strip old bolt heads. A small flat file can be useful to get rid of burrs if the head of the old 5-piece was damaged a bit during installation, otherwise you may not be able to get the 6-sided wrench/socket on the bolt head.

Greg Barnes wrote:

It hasn't been talked about much because a lot of people have failed to get it to work with 1/2" bits and lighter weight drills. We used to do it now and then when replacing bolts in Owens River Gorge around 2000 or so, using the old big heavy Hilti TE-6A. The 3/8" drill bit method seems to work even with lighter weight drills, but it takes much longer/more battery power than a heavier duty drill.

There are a few main things to watch out for when drilling through 3/8" sleeves and cones with a 3/8" solid-head SDS bit. It's best to have a bigger, heavier duty 36V drill, not the lightest weight 36V Bosch for instance (which I think they don't even sell anymore?). 

Thanks for all the great info Greg. I have one of the newer 18V Bosch drills but could get my hands on a beefier one. Seems like advancements in bit technology someday could make drilling through sleeves and cones more practical?

I wouldn't attempt anything like this with an 18V. So far the drill bits available are not so great, if you actually get a quality metal drilling bit (and a SDS chuck adapter), it still doesn't work that well and the bit can also bind (rotary only mode, not hammer drill mode). Not much different from a solid head carbide bit in hammer mode.

Sleeves pull fine in some rock, but not in most harder rock. Also if the sleeves/cones are really rusty, they tend to disintegrate and come out pretty quickly and easily by drilling through - but then the chances of the bolt snapping in the first place are much higher.

I've used this method with success on 1/2" rawls, sometimes I would have to upgrade to a 5/8" inch glue in because of what it would do to the hole.  I use the new 18v Bosch worked fine for it. Looks like you already got lots of good info from Greg and others.  A really thin long pair of needle nose and a small screwdriver can be helpful. 

I have drilled through the sleeve without issue. However, drilling the cone does not always work very well. You can try it, just be sure ALL the metal has been removed. I've drilled cones to find all the drill bit did was hollow them out but there was still a thin layer of metal in the hole. If you insert a new bolt into that, you're just attaching the new bolt to a piece of thin metal, not the rock itself. Drilling a 3/8" RAWL with a 1/2" bit is much easier than drilling a 1/2" RAWL with a 1/2" bit.

Typically, this method can be relied on as a last resort when more sophisticated methods fail. It doesn't save time once you get proficient with a tap/puller combo. One out of 10 or 20 goes, you don't get all the parts and pieces out, and it's time for the square peg for the round hole. For a 3/8" 5-piece, definitely use an old 3/8" bit. This allows for some feel to fish out the chunks right about when the drill starts to bind. Hard on the drill, but the next gen 18v drills do it just fine apart from the binding and stuck bits. A second vote for having some vice grips for stuck bits.

Have an old 1/2" bit on hand as well. As 20kN hints, metal remnants can get pushed to the periphery or bottom of the hole. Sometimes the best option is to push all the metal to the end of a hole drilled beyond the embedment of the bolt. Overall, it's very reasonable to remove the sleeves and cones if the bolt stud can be loosened. It's a bummer when the bolt studs are seized up and snap, so best to have good positioning and leverage to apply controlled force when trying to back them out. Another good tip from one of the engineers at BD is to grind the taper from the face of your sockets to maximize the surface area in contact to help a avoid stripping the hex head.