removing bolts

In the "which kind of bolt" thread it is clear most bolts eventually need replacing. What is the best way to remove a wedge anchor? Concerns would be rock damage obviously. Crowbar? Beat it back and forth until it breaks then push the stump in the hole? Simply remove hanger and put new one next to it? Just seeing if there is a concensus out there.

For a wedge anchor, I usually unscrew the nut, remove the hanger, and pound the stud into the hole with a hammer. (I do this on holes that I know are deep enough: holes that I have drilled, and I want to reposition the bolt).

If the hole is deep enough, you can get the end of the stud slightly below the surface of the rock. I use the pointed tip of my hammer to drive the stud in. Then put some clear silicone caulk over the hole, put a small rock on top, smash the rock with a hammer, and smooth out the fragments to hide the hole.

Find a spot to drill another hole nearby (3"-6" away) for a replacement bolt. Make sure the new hole is in solid rock and can be clipped from the same stance as the old bolt.

If you're installing another wedge anchor, drill the hole at least 1/2" deeper than the length of the bolt, so the stud can be pounded into the hole when/if the bolt has to be replaced.

Ron Olsen wrote:For a wedge anchor, I usually unscrew the nut, remove the hanger, and pound the stud into the hole with a hammer.

One thing I've done different than the above with reasonable success is to, instead of pounding the stud into the hole (especially if you don't know if the hole is deep enough), whack the stud with a hammer a few times until it shears off. Will usually shear off flush or slightly recessed from the hole. Then, if you need to drive it into the hole, use a punch.

I've used JB weld or plumbers two part epoxy to patch holes. A bit of rock dust from nearby can match the local rock color and hide the damage pretty well.

Another trick I've heard Mike White mention (maybe he'll post up here) is to core out the placement and drill the stud out. He has a nifty method for that. Then replace with the next size up fastener, so, you don't need to drill another hole.

One thing to also consider, space out the next placement by assuming a certain length for the stud (if you can see the letter on the end, C, D etc you can better guess the length) and make sure you space the next placement a "minimum" distance from the old hole. Use the Powers or Hilti guide to help estimate how far this is, but, I think the rule of thumb might be at least the length of the bolt away or twice the length of the bolt for a full strength placement (assuming a functionally loaded bolt probably). See:

powers.com/pdfs/mechanical/…

I have successfully removed some old ones with a crowbar (24" handle but longer woulda been better). I think this is unusual though. My new method is to overtighten them until they break, then punch them in and patch. Much cleaner than other methods and you don't have to worry about the hole being too shallow. I also found this on the internet lately. It's $30, and I bet it would be slow. They only go down to 3/8" so no 1/4". Still, it is intriguing. It operates in rotary only mode in an sds chuck. Made by Relton. This thing would probably shred 5 piece and taper bolt sleeves in 3/8 and 1/2".

There are also rotary only core saws that would work on 1/4" but I'll bet in hard rock they would not work well.

The core drill method works best on 1/4" bolts. Use petzl self drilling bolts. They get dull quick so it takes 3-4 of them ,and hand drill them out. The 1/4" bolts are too weak to pull out but
I have had good success pulling 5/16" and 3/8" wedge bolts with a funkness and a special hanger. The climbing hangers make the bolt bind in the hole. You need to pull straight out with a B.F. hammer.
Weld a 3/8" nut between a u shaped pice of steel or use a welded eye bolt and a rod coupling. After a few yanks tap it back in and yank harder try to work it out slow. This method is about 50/50 and works in veary solid rock, dont try it in sandstone.
Try to remove it first if the bolt breaks with a funkness and a hammer then patch it and drill a new hole.

I have considered the rebar bit before and used one on the job.
But it does take forever. It was not pratical before, but now I have a gas powered ryobi. We should give it a try. Send me a link for them rebar bits or order a couple and I will cover the tab. 30 bucks is cheap for these, The last one I used was 98 bucks.

Hope this helps.
mike white
asca

I have got out a couple of 1/4" button head bolts with a crowbar. The head must start off unbroken with this method obviously. Helps to have a crowbar with a thin head to slide/pound under the hanger.

Get the bit at mcmaster.com. Also a cheap source of Powers bolts.

Crowbars are too much work. Tuneing forks work best for rawl split shank bolts (buttonheads). Contact greg with the asca to get one.
If he is out I will get one made and hook you up.

I now make my own out of large bugaboos and love them to death.

mike
asca

This summer I will be busy replacing old bolts at our local cliff. I was wondering where I could get my hands on a knife blade and LA "tuning fork". Almost all the bolts I will be replacing are old 3/8 wedge with homemade hangers. It would be nice to pull them and replace them with 5 piece. Although breaking them and hammering them in with a patch to cover it may be the only solution.
Thanks,
Jesse

Greg wrote:If I remember right, the tuning forks are only good with 1/4" bolts.

You can kinda tune them (ha ha) to deal with a 3/8" or 5/16" bolt shaft too. Just grind the inside a tad to fit. I've used them to just start a bolt up, which, is really where they shine. Just enough to get a crowbar or something larger underneath the hanger.

My bet is the bugaboos work pretty well, given that sometimes you just want to loosen up and lift the hanger a tad, to get something bigger under there to pry on.

Monkey Mike is the man when it comes to pullin' old bolts.

Still wonder if some type of gear puller/cherry picker with a custom hanger (ala Mike's suggestion above) might work. On some old bolts, I can imagine busting the threaded shaft off when trying to remove the nut, though.

For 3\8 wedge bolts I use my funkness and a small sledge to yank them out.

Take the old hanger off and screw on a rod coupling (3\8 nut 2"long)
then thread a round eye bolt into the coupling so you are pulling straight out on it. Now Yank away

A sledge sounds like a good idea...how do you attach the funkness to it? I've pulled some 3/8" split shaft bolts with my normal wall hammer and my wrist and shoulder still remind me of it. Also where do you get the rod coupling and round eye bolt?

Also do you ever find that most funkness devices are a bit short for removal projects like this?

I welded a big 1" nut on my sledge to clip into.
The couplings and eye bolts you can get at any nut and bolt supply store.

A regular funkness clipped into a sledge is plenty long.
But I still carry 3 different sizes of funk cables. If you want a longer one let me know I make my own.

mike
asca