Drilling Out Expansion Anchor

[Deker]

I've got some railing on my front porch that was removed with the anchors cut down and ground flush to the porch. Now I've got to put the railing back on, preferably in the same spot. What are my options for removing the embedded anchor? Can I drill it out with a cobalt bit?

 

[rustyjames]

I would core drill it. I think those anchor bolts are hardened steel and not easy to drill.

 

[The Cobbler]

what kind of anchor? got a picture?

 

[Deker]

Not sure exactly, but I'm assuming they are wedge anchors. Please see pictures attached.

 

[The Cobbler]

they are likely hardened. that plus seized into the concrete makes it tough . try to drill it & see what happens. good luck!

 

[Deker]

Thanks. Any recommendations on type of bit to use?

 

[infinkc]

just curious if you tried to hammer them down, sometimes they drill all the way through the concrete when making the holes. if the case they would just go into the dirt below. i have had good luck doing that before.

 

[gmwelder86]

Rebar water. Will be drilled out in minutes. Have had to do it at work 3/4 anchor no problem.

 

[TexMedium]

Rebar water. Will be drilled out in minutes. Have had to do it at work 3/4 anchor no problem.

Don't tease like this!!! What is "rebar water"?

 

[LS6 Tommy]

If it was you who did that, I mean no disrespect, but cutting them off like that was a hack job thing to do. If those bolts originally went into some sort of expaning anchor I'm afraid that if they don't punch down and out the bottom like infinkc said, they may be there forever unless you can carefully centerpunch them and drill them out.

Tommy

 

[matt_i]

It costs significant extra to get a Grade 5 wedge anchor at McMaster Carr...

Most of them that I've ever purchased are Grade 2-ish bolts, very soft.

None of these grades of steel fasteners, including Grade 8 stand a chance against a sharp HSS drill bit.

They simply can't be that hard (that a HSS drill bit won't touch it) or there would be large liability from the high potential for brittle fracture.

It is definitely possible to dull the drill bit if it touches the abrasive concrete.

Mainly its an excerise in persistence!

 

[Super Mech]

Don't tease like this!!! What is "rebar water"?

I’m curious too.

 

[Deker]

If it was you who did that, I mean no disrespect, but cutting them off like that was a hack job thing to do.

I agree. We just moved into the house and this was something our contractor did during the remodel. He's off the job now and I'll be spending time going over and fixing some of his subpar work.

I could slide the railing over slightly and abandon the existing bolts, but the base plate is so small that they would be exposed. If I can hammer or drill them down enough to patch and paint then I suppose that would work, but I was hoping there was some way to reuse the holes.

If hammering them down or drilling them with an HSS bit doesn't work I'll pick up some cobalt bits (M35 or M42?) and try again.

Thanks everyone for your suggestions!

Rebar water. Will be drilled out in minutes. Have had to do it at work 3/4 anchor no problem.

Is that some type of corrosion accelerator??

 

[like2wheel]

Don't tease like this!!! What is "rebar water"?

I bet it's Siri's interpretation of "rebar cutter" drill bit.
Or a similar autocorrect tragedy



.

 

[Marctrees]

Can you move the flange over a bit in some direction ?

Marc

 

[The Cobbler]

drill new holes in the flange , centered between the existing .

 

[Bighead38]

If you can’t get them out could you put a bigger plate to cover them up and go through the bigger plate with the railing?

Like this but the bottom plate would be bigger to cover the old holes

Could you put trim around the base to cover old holes?

 

[Marctrees]

If the existing studs can be drilled, drill and tap for 1/4" or much better 5/16" and refasten w stainless machine screws w neverseize.

If one falls apart, then epoxy in a stud.

Or some such combination.



Marc

 

[RPH]

House might be old enough to use lead anchors. We had some on the house I grew up in. Decided to scrap railing and as a kid what more fun then destructing something. It used soft lead anchors and they came out without much fight. Only thing left was the hole they were in.

 

[GMCGarage]

I've got some railing on my front porch that was removed with the anchors cut down and ground flush to the porch. Now I've got to put the railing back on, preferably in the same spot. What are my options for removing the embedded anchor? Can I drill it out with a cobalt bit?

you would need a stationary drill to get all the way thru. I would get a spiral end mill bit, and use that, get them down as far as you can, and then use a flush drop in anchor. Since its a corner, you dont need a deep anchor, as each direction will provide stability and bracing.

 

[Rt jam]

If it was you who did that, I mean no disrespect, but cutting them off like that was a hack job thing to do. If those bolts originally went into some sort of expaning anchor I'm afraid that if they don't punch down and out the bottom like infinkc said, they may be there forever unless you can carefully centerpunch them and drill them out.

Tommy

Please tell us the preferred method.

 

[James-W]

Do you know exactly what type of anchor bolts they are? What I am getting at is, some anchor bolts you tap a soft metal nut in the hole, then you screw a bolt thru the bottom of the railing and into the soft metal nut. The soft metal nut expands when the bolt is turned into it, and then you have a solid railing.

If you have that type of anchor bolt, or something similar, then maybe you could weld a little smaller bolt on top of the ones in the concrete and just turn them out. I am not saying this will work, but it MIGHT work if the anchor bolts are the right type.

 

[SGKent]

there are some videos out there that use this same principle to remove a standard type wedge bolt where the bolt and wedges are one assembly, made of steel, or steel and lead. There are some other type wedge bolts with hardened steel wedges that have nubs on them that I don't think it would work. https://vimeo.com/124880350

Consider this solution.