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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Installed Sound/Contracting => Topic started by: Mike Sokol on December 23, 2014, 06:57:32 pm

Title: Removing Tamper-Proof Bolts
Post by: Mike Sokol on December 23, 2014, 06:57:32 pm
I've just finished an install of new speakers at a church and pulled down the old speakers, only to find that the brackets were lagged into the concrete block behind the plaster wall using tamper-proof breakaway screws. They're about 14 ft up on the wall with a lot of expensive statues and marble in the area. So do I drill these bolts out? Use a chisel and try to snap off the heads? Get an air powered saw like I used to use on exhaust pipes? Or is there something a little less messy with a lot less vibration, noise, dirt, etc...?
Title: Re: Removing Tamper-Proof Bolts
Post by: Steven Barnes on December 23, 2014, 07:13:58 pm
I would try to drill them out, if that did not work I would go with the grinder/cutoff disk to take the head of the bolt off. The second will be a bit messier, but still not too bad as long as you are only cutting the head off. Keep in mind you will probably have to grind the bolt flush after the bracket is removed unless they are not in a visible location.

The air chisel is usually a PITA to deal with the tool, compressor etc.
Title: Re: Removing Tamper-Proof Bolts
Post by: Josh Millward on December 23, 2014, 07:17:20 pm
Or you can use a dremel tool to cut a groove in the head and use a flat headed screwdriver tip on a driver to back it out.

Of course, success using this method will depend on the size of the bolts. Bolts that are smaller will be easier to deal with in this way, but large ones could be difficult to remove this way.
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on December 23, 2014, 07:37:40 pm
Hmmm....

Now I remember Easy-Out taps. Drill a hole in the center of the bolt, then the left-hand tap jams in the hole and lets you back it out. As long as the bolt isn't hardened this should work. It's been 40 years since I've done this but we used them on trucks all the time.
Title: Re: Removing Tamper-Proof Bolts
Post by: frank kayser on December 23, 2014, 09:59:18 pm
My vote would be a Dremmel with a cutoff wheel as my first effort as Josh suggested. Get the reinforced wheels - they break far less often.  I've removed many this way.  Be patient and make a good slot, not too deep as to give the bolt head a chance to break off. Just try to keep the slot sides square so you don't cam the things.
Freshly dress the screwdriver on the grinder before you set out.


Also, should you choose the dremmel, if you cut two slots at 90 degrees all the way to the bolt shank, the head will probably break off in quarters pretty easily.


Easy outs would be my third choice, but given the bolts are tamper proof, they just may be hardened.
Easy outs will take more time, too.  My luck with easy outs has not been all that positive.  I've broken more easy outs than I care to count.  They have to be made harder than the anticipated bolt, and though tempered, they are still quite brittle.


good luck, Mike!
frank
Title: Re: Removing Tamper-Proof Bolts
Post by: Mark Cadwallader on December 23, 2014, 10:32:44 pm
Mike, what is your purpose in removing the tamper-resistant bolts?  Do you need to re-use the threaded insert, or just clean up the old install by removing the existing brackets?  If the later, I would probably just use an abrasive cut-off wheel on a die grinder and cut them off flush with the wall.  There are electric die grinders (a Dremmel tool on steriods and meth) that are pretty robust. You will shoot a trail of sparks as you burn the steel away, but that shouldn't be too hard to contain with appropriate tarps/drop cloths. Wear appropriate PPE; eye and ear protection is a good thing.  (But you know that.)  Mark C.

Edit: Just snap the hex head off; less material to cut through that way. Once the hex is gone, you have what is basically a non-slotted truss head screw. Slot it or burn it away. Drag link sockets are a good way to get a wide, strong straight-bladed bit, btw.
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on December 23, 2014, 10:44:22 pm
Mike, what is your purpose in removing the tamper-resistant bolts?

I just need to remove the brackets, plaster the holes, then repaint. I don't need to reuse anything since the new speakers are already mounted in a totally different spot.
Title: Re: Removing Tamper-Proof Bolts
Post by: Chad Graham on December 23, 2014, 11:35:56 pm
Left handed drill bits will pull then out..
Title: Re: Removing Tamper-Proof Bolts
Post by: Steve M Smith on December 24, 2014, 03:42:17 am
Get the reinforced wheels - they break far less often.

It's usually only once each!


The left hand tap option seems the best to me.  If you don't have the taps for it, a right hand tap with a machine screw and very tight locking nut could work.





Steve.
Title: Re: Removing Tamper-Proof Bolts
Post by: John Roberts {JR} on December 24, 2014, 08:54:34 am
I've never used left handed drill bits but they sound like the perfect tool for this job.

Easy-outs are brittle. If you haven't broken an easy out, you haven't used them much.

JR
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on December 24, 2014, 09:13:04 am
Easy-outs are brittle. If you haven't broken an easy out, you haven't used them much.

Yeah, IIRC it's impossible to drill out a broken Easy Out. We don't have to pull out these brackets until after the holidays, so we'll take tools for all contingencies we can think of, start simple, and keep experimenting until we have success.
Title: Re: Removing Tamper-Proof Bolts
Post by: Stephen Swaffer on December 24, 2014, 07:43:10 pm

Easy-outs are brittle. If you haven't broken an easy out, you haven't used them much.

JR

+1

The "Easy" in the name HAD to come from marketing-certainly not a nickname!

My vote is for the dremel with the grinding disks-if I wanted to save brackets, etc I might try Easy outs, etc-otherwise time is money and grinding the heads off, while it may damage the brackets slightly will get them off.
Title: Re: Removing Tamper-Proof Bolts
Post by: duane massey on December 25, 2014, 01:24:05 am
Small grinder with a diamond-cut blade. If you don't need to re-use the brackets this will be the quickest removal, and the blade will last for a long time.
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on December 25, 2014, 09:59:15 am
Small grinder with a diamond-cut blade. If you don't need to re-use the brackets this will be the quickest removal, and the blade will last for a long time.

My contractor has already recommended the diamond cut blade in a grinder route. We're going to have to cover up everything since there's a pair of antique life-sized statues within a few feet of these brackets. And I don't care if we trash the brackets, we just need to get them off the wall for plastering and painting. I'll be sure to take pictures of this...
Title: Re: Removing Tamper-Proof Bolts
Post by: Tim Padrick on December 27, 2014, 01:20:05 am
I've never seen that type.  If they break off when removing them, why don't they break off when installing them?
Title: Re: Removing Tamper-Proof Bolts
Post by: Steve M Smith on December 27, 2014, 06:25:31 am
If they break off when removing them, why don't they break off when installing them?


That's a very good question!


Steve.
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on December 27, 2014, 08:08:44 am
I've never seen that type.  If they break off when removing them, why don't they break off when installing them?

When installing them you keep applying torque until the bolt section sheers off, then A) you know that they're tight enough, and B) they're not coming back out easily.
Title: Re: Removing Tamper-Proof Bolts
Post by: Steve M Smith on December 27, 2014, 08:39:20 am
... and a very good answer!


Steve.
Title: Re: Removing Tamper-Proof Bolts
Post by: Tommy Peel on December 27, 2014, 12:57:37 pm
Ease-Outs make me cringe.... I worked in a tractor shop for a couple of years a few years ago and had more experience with those than I care to think about....
Title: Re: Removing Tamper-Proof Bolts
Post by: Jamin Lynch on December 27, 2014, 01:26:00 pm
When installing them you keep applying torque until the bolt section sheers off, then A) you know that they're tight enough, and B) they're not coming back out easily.

Wait, are the heads still on? Surely not. :o

How tight are they? Can you grab the shoulder with a large pair of channel locks or vise grips? Maybe they are loose enough to turn out.
Title: Re: Removing Tamper-Proof Bolts
Post by: Craig Hauber on December 29, 2014, 11:08:26 pm
Wait, are the heads still on? Surely not. :o

How tight are they? Can you grab the shoulder with a large pair of channel locks or vise grips? Maybe they are loose enough to turn out.
Jamin has the right idea.
I have used a pipe wrench to dig into and grab the little-bit of shoulder at the base of the cone.  Grinding 2 flat spots on either side helps too if they are being stubborn,  (pound on them good too -tends to loosen their grab to the concrete)
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on December 29, 2014, 11:41:14 pm
Jamin has the right idea.
I have used a pipe wrench to dig into and grab the little-bit of shoulder at the base of the cone.  Grinding 2 flat spots on either side helps too if they are being stubborn,  (pound on them good too -tends to loosen their grab to the concrete)

Guys, reality check...

This is in a Catholic church with lots of marble and a pair of antique life-sized statues very close to the brackets that can't be moved. The walls are 100 year-old plaster and I don't want to start any cracks. And these speaker brackets are 14 ft up off the floor with antique marble alters right beneath them. Oh yes, the floors under the brackets are also marble so I can't bring in a lift since it might crack the floor. Gotta do this from a ladder.

Hey, if it was simple or obvious I wouldn't be asking for suggestions. But if the original installers had put in standard concrete lag bolts this job would already be finished. I think we're going to have a go at this next week with a diamond cutoff blade in a hand grinder and see how it goes.
Title: Re: Removing Tamper-Proof Bolts
Post by: Steve M Smith on December 30, 2014, 04:30:19 am
Guys, reality check...

This is in a Catholic church with lots of marble and a pair of antique life-sized statues very close to the brackets


So dynamite is out then?!!




Steve.
Title: Re: Removing Tamper-Proof Bolts
Post by: Jamin Lynch on December 30, 2014, 08:41:36 am
Guys, reality check...

This is in a Catholic church with lots of marble and a pair of antique life-sized statues very close to the brackets that can't be moved. The walls are 100 year-old plaster and I don't want to start any cracks. And these speaker brackets are 14 ft up off the floor with antique marble alters right beneath them. Oh yes, the floors under the brackets are also marble so I can't bring in a lift since it might crack the floor. Gotta do this from a ladder.

Hey, if it was simple or obvious I wouldn't be asking for suggestions. But if the original installers had put in standard concrete lag bolts this job would already be finished. I think we're going to have a go at this next week with a diamond cutoff blade in a hand grinder and see how it goes.

I still think it would be worth a try with channel locks before you start grinding. If it's a 3/8" Grade 5 bolt it should only have about 25 ft lbs of torque.

Scaffold would be safer than a ladder. You could get another person up there to help. Plus the platform might catch anything you drop.
Title: Re: Removing Tamper-Proof Bolts
Post by: Josh Millward on December 30, 2014, 10:55:09 am

So dynamite is out then?!!




Steve.

Obviously.

That is the only right answer here.
Title: Re: Removing Tamper-Proof Bolts
Post by: g'bye, Dick Rees on December 30, 2014, 11:29:44 am
A quick, curious look at YouTube videos for removing stuck bolts was fun.  A lot of mechanics and welders...

I'm currently in favor of scaffolding for whatever work is done.  I'd personally go with grinding a slot first, then tapping/drilling and the LH threaded remover.  A short, carefully administered burst of vibration from perhaps a hammer drill might help loosen the grip of the threads.

I used to have an impact driver which would deliver a LH twist when struck with a hammer.  It's still on the premises somewhere...but I know not.  This was a great little tool which would deliver the twisting force and administer the pressure required to make a good grab on a drilled hole in the bolt.

Know any marble sculptors???  Might be helpful to get an artisans opinion on working in stone...
Title: Re: Removing Tamper-Proof Bolts
Post by: John Roberts {JR} on December 30, 2014, 11:31:51 am
KISS, do no harm...

JR
Title: Re: Removing Tamper-Proof Bolts
Post by: g'bye, Dick Rees on December 30, 2014, 11:39:30 am
KISS, do no harm...

JR

Have the priest bless the tools...
Title: Re: Removing Tamper-Proof Bolts
Post by: frank kayser on December 30, 2014, 12:08:28 pm
Have the priest bless the tools...
Amen!
Title: Re: Removing Tamper-Proof Bolts
Post by: Stephen Swaffer on December 30, 2014, 09:46:38 pm
And standby in case you fall of the ladder onto the marble floor.
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on December 30, 2014, 09:53:24 pm
And standby in case you fall of the ladder onto the marble floor.

Hey, I don't work on live electric boxes alone, and I don't climb ladders without someone else in the room who can call 911. That was the first thing I made sure my kids knew how to do... call 911 and perform basic CPR.  ;D
Title: Re: Removing Tamper-Proof Bolts
Post by: Steve M Smith on December 31, 2014, 05:24:24 am
That was the first thing I made sure my kids knew how to do... call 911 and perform basic CPR.  ;D


I'm covered there.  My son is training to be a paramedic.


Steve.
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on January 21, 2015, 04:08:54 pm
Well, we got the tamper-proof bolts out today, filled in the holes, and repainted. As promised, here's some pictures. The first thing we found out was the bolts were hardened and a carbide drill bit wouldn't even scratch the surface. So my fabricator Karl got out his diamond cutoff saw and sliced off the heads. Only took about 30 seconds per bolt to cut off the heads, and there was relatively little mess. We punched in the bolts below surface, used epoxy filler on the holes, sanded the wall with a drywall plane, then repainted the entire area. Looks perfect and only took two hours including setting up the ladders with pads over the marble alters, and a thorough cleanup. Well worth it to hire a contractor who does marble and drywall everyday, and who has all the right tools for the job.
Title: Re: Removing Tamper-Proof Bolts
Post by: Keith Broughton on January 21, 2015, 04:20:38 pm
It's clear now what your concerns were about surrounding "stuff"!
Nice job.
The ladder looks like it's got it's hand up in defense  ;D
Title: Re: Removing Tamper-Proof Bolts
Post by: frank kayser on January 21, 2015, 04:23:52 pm
I love the gloves up on the ladder...
Looks like they're reaching up in prayer (as in Thank God this project is DONE!)  :)
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on January 21, 2015, 04:50:52 pm
I love the gloves up on the ladder...
Looks like they're reaching up in prayer (as in Thank God this project is DONE!)  :)

Exactly...

Karl said that gloves on the ladder is an old painters trick so you don't scuff up the wall.  Both the ladder and the statue were praying for us. You can see the antique marble alter right below, so we put down rubber padding and covered it all with drop cloths. I also had my wife do a faux finish on the new Entasys speakers which you can see mounted on the face of the columns. She's an artist who specializes in murals and faux paining, so she was able to match the grain and stain of the existing 100 year old wood. I love working with professionals, even when they're not really doing "sound".

A fabricator is a great guy to know. Tomorrow we're at another church cutting a hole in the side of the platform for a digital stage box, and Karl's framing it out and putting in rack rails while he's on site. He'll match the style of the molding and paint it the same color as the rest of the room so this will look like it's been there forever. I normally don't worry about things like this for my portable gigs, but church installs demand this sort of attention to detail. So it not only sounds great, it looks great too. The pastor is really thrilled with the install which we were able to finish in time for his birthday celebration.   
Title: Re: Removing Tamper-Proof Bolts
Post by: Mark Cadwallader on January 21, 2015, 08:49:10 pm
Looks good, Mike. If you don't need a specialty skill (or specialty tools) it often is much cheaper/faster/better to hire somebody who does. (Isn't that just what we tell our clients?). Mark C.
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on January 21, 2015, 09:16:18 pm
Looks good, Mike. If you don't need a specialty skill (or specialty tools) it often is much cheaper/faster/better to hire somebody who does. (Isn't that just what we tell our clients?). Mark C.

Yeah.... Trying to save a few bucks doing something you're not an expert at can cost more in the long run. I'm trying to do high-end install jobs, so we need high-end finishes. I'm confident in my ability to tune a room, but not so much when it comes to drilling a hole in marble or painting a wall.  8)

I've been asked to design a bunch of sound systems in churches with a lot of marble and fancy carvings. And, of course, all wiring needs to be invisible. I plan to sub out the drilling and fabrication to someone who does a lot better job than I could in way less time.
Title: Re: Removing Tamper-Proof Bolts
Post by: Stephen Swaffer on January 21, 2015, 11:01:48 pm
I agree with subbing out for sure.  Have to wonder what they were worried about that made them use tamper proof bolts in that location? 
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on January 22, 2015, 03:23:12 pm
I agree with subbing out for sure.  Have to wonder what they were worried about that made them use tamper proof bolts in that location?

I have NO CLUE as to why they would do something like that. For my new speaker brackets we put threaded rod all the way through the block wall with large fender washers on the back side. I'm pretty sure the new brackets would hold up a truck if they needed to. I just don't trust expansion anchors in cinder block to hold up speakers hanging in the air. I'm not a rigging guy but I do have a degree in Mechanical Engineering, so I'm always aware of the stresses on this sort of installation. I know I'm paranoid, but am I paranoid enough?  ;D
Title: Re: Removing Tamper-Proof Bolts
Post by: Stephen Swaffer on January 23, 2015, 06:00:34 pm
I had to install some gooseneck architectural fixtures on the front of one of the 100+ year old buildings on our town square.  The brick on these buildings is either too soft to hold anything, or so hard it burns up carbide drills.  The research I did pointed to epoxy anchors being some of the best for that application-but I ended up using expansion because of the time of year and ambient temps. They were  much lighter than speakers, but being outdoors, my biggest concern was wind loads.
Title: Re: Removing Tamper-Proof Bolts
Post by: Scott Holtzman on January 23, 2015, 06:20:19 pm
I have NO CLUE as to why they would do something like that. For my new speaker brackets we put threaded rod all the way through the block wall with large fender washers on the back side. I'm pretty sure the new brackets would hold up a truck if they needed to. I just don't trust expansion anchors in cinder block to hold up speakers hanging in the air. I'm not a rigging guy but I do have a degree in Mechanical Engineering, so I'm always aware of the stresses on this sort of installation. I know I'm paranoid, but am I paranoid enough?  ;D

You certainly did a nice job installing the new speakers from an aesthetic standpoint.  It sounds like your clients appreciate your attention to detail and that makes it very satisfying work. 

Certainly all thread with backing washers is the best possible way to distribute the load.  Since I always have a ton of unistrut and never fender washers that is usually what ends up on the other side.  I truly think Unistrut and spring bolts are divinely inspired  :)

Have you ever heard horror stories of install crews in churchs?  One my competitors was caught playing death metal at full tilt boogie in one HOW, I had a helper the just couldn't stop with the F-bombs at my church and I had to send him home.  My point is not everyone cares like you clearly do.

Title: Re: Removing Tamper-Proof Bolts
Post by: Mark Cadwallader on January 23, 2015, 06:49:23 pm
I agree with subbing out for sure.  Have to wonder what they were worried about that made them use tamper proof bolts in that location?

Use of a bolt with that style of tamper-resistant head is one way to ensure the correct torque has been applied. I have no clue if that was why it was used, however.  Mark C.

Edit:  That's a real-life application of the old mechanic's joke of "tighten it till it breaks, then back off a quarter turn."
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on January 23, 2015, 07:14:18 pm
You certainly did a nice job installing the new speakers from an aesthetic standpoint.  It sounds like your clients appreciate your attention to detail and that makes it very satisfying work.

Thanks... I'm just starting to design and manage church AV installs, having taught sound system setup and mixing for thousands of churches around the country over the last 15 years. I don't pretend to know everything about HOW audio, but I know a LOT of things that don't work. And it always made me mad to see shoddy system design and installation in any church. So we're gathering some really great subcontractors as well as install crew and trying to raise the bar for what's expected with a HOW install. None of our install guys will smoke cigarettes anywhere near or in a church, and I give everyone in the crew an overview of any special things to be aware of for a particular denomination. For instance, we're currently doing a big A-V install for a Seventh Day Adventist church, and they don't drink anything with caffeine or eat pork. In fact, many of the SDA churches I've taught at are vegetarians. So we don't walk into their sanctuary holding a cup of coffee with a bacon and egg sandwich. It's just a sign of respect that we're glad to do for any of our House of Worship customers. Seems strange that the other installers in the area don't treat their own customers the same way. And yes, we're hearing reports of other install crews dropping F and S bombs all the time, even in front of the pastors. Seems like a bad idea...

So here's the latest stage box install yesterday. We had to cut out a few structural beams under the stage to make this fit, so Karl built a new header and ran side-plates to the concrete floor. That way anyone jumping on the stage won't feel any flex over top of the stage box. Plus he built a picture frame around it to cover up the carpet edges. We ordered the rack rails in advance so Karl could double-check the actual fit and setback with the box in place. The media director was thrilled and says it looks like part of the original stage build. Took him around 4 hours to build and install everything starting from scratch. Like I said before, a good fabricator is a great guy to know.
Title: Re: Removing Tamper-Proof Bolts
Post by: Mike Sokol on January 23, 2015, 07:24:06 pm
Use of a bolt with that style of tamper-resistant head is one way to ensure the correct torque has been applied. I have no clue if that was why it was used, however.  Mark C.

That's what we thought at first, but in fact they were pretty loose and would pull out a fraction of an inch with a little crowbar action. I don't think they would have dropped a speaker, but there could have been sagging brackets in a few years since these were only in about 18 months so far. I guess they put these in with an impact wrench until the drive heads broke off. I'm not a fan of this type of installation.