Best Method to Remove Shot Fire Nail

powder gun nails are case hardened...almost impossible to grind down. Get a 'Wonder Bar" and carefully drive the flat end under the plate until it contacts the nail. Then give it a sharp tap on the bent end of the Wonder Bar and the nail will 'pop' out of the concrete, leaving a small hole you can fill later with grout.

I have seen some fasteners that can be injected into metal which is ductable and fills the shape of the fastener to have a some good grip. With Concrete or ceramic, There is serious problem of developing creeping crack type defect in the concrete slab and curing such concrete is also going to be nearly impossible.

I think if velocity of the fastener matches with the velocity of ultrasonic in the concrete then shock wave may allow the faster to get in without having much damage. I have never tried such thing but it may be worth trying. Some information may be available from gun manufacturers who manufacture concrete penetrating bullets. Such bullets are either made to drill hole or to get embedded.

Yes I know you can do this, but in practice with concrete, it's the "lazy" way to fasten material. If I own the structure, there's no way I would do this to my property. But it does get the job done "cheaply", and in the end most people have no skill to do this work themselves, so hire a contractor that really does not give a darn long term of the damage done, but can collect their $ and run. I truly believe this causes permanent damage to the concrete surface. And most people don't care, as everything is temporary to them. Any demo work I've ever done, where this was used (and this was all concrete only usage), leaves damage, I've not seen any exception to this observation.

ignator

For unplanned fixture, normally drilling, and then filling with soft sleeve of some elastic material and letting the screw driven fastener to set in place is what most of the people do in my house. Concrete drill does limited damage. Removing fastener is just unscrewing out the fastener.

For the ceiling, we make provisions well ahead but some fixtures like changing false ceiling, people may end up drilling in same way. Shooting fastener for concrete are not much in use here. As far as removing such fastener, one may perhaps need to drill or just can level out to the surface and leave it there as such..

I don't believe Kalifornia allows the use of powder activated nails in sill plates anymore due to seismic concerns. They reverted back to requiring 1/2 in. j-bolts in the foundation, minimum 6 ft. O/C and within 1 ft. of any doorway/opening. I believe this change occurred in the mid 70's.

C4

It's all about the kaboom.

I think it would be worth the effort to build your trusses so that they are self supporting, eliminating the need to nail into the floor altogether.

If you want to prevent it from sliding around, I would use some kind of adhesive and tack weld it to the floor. This could simply be scraped off afterwards.

Drill them out.

But if you have to go to a lot of trouble removing them, why not use inserts and screws in the first place?

I need to erect a high column / wall formwork.

Such formwork was prefabricated. A crane lift it to position and I need to temporary stablize it very quickly or I loss money from the crane.

I use truss to restrain any possible movement (collapse) of the formwork.

I think drilling / polishing can remove the fire nail effectively. The concrete slab will be covered by screeding later.

Anyone has tried this method before?

The reason that the nails can penetrate metal, concrete, is because they are very hard! It is unreasonable to believe that you can drill them out!

Grind them down then remove the truss, them grind them even with the concrete, then leave them alone!

Angle grinder is the only and low cost solution and its the best home DIY kit tool. You can easily cut metal with angle grinder.
You can get the best angle grinder from any hardware shop.

Use a pair of wedge-type expansion anchors, otherwise you will cause irreparable damage to the concrete if you use a powder-charged anchor/penetrator.

All you have to do is drill some holes in the top of the concrete surface aligned with two holes in the truss seat (hopefully steel). You need to prevent lateral rotation of the truss bearing ends.

After you are done with using the truss, all you have to do is loosen the anchor bolt nuts and pull out the anchor shafts. If they are permanently wedged you can cut-off the projections with a cut off saw.

I agree with Tornado, who suggested grinding the nailhead to remove your temp truss and then grind off the remaining stub nail shank.

Powder actuated fastening is very common and very effective. Some spalling of the concrete at the nails is inevitable, but for one reason or another your question does not include this as a concern or regard. So fire away, it will be fine.

Is this the way you use it?

http://www.youtube.com/watch?v=DccKN7rdz40

With out a completely accurate, sketch/detail of what the cross-section of the truss member in contact with the concrete of what width, what depth, and approximately what strength, we can only make a semi-educated guess as to what the actual conditions are.

May we please see more relevant details?

The abrasive wheel as said before. But if some length of the nail is sticking out you may want to try bending it back-and-forth with a hammer; and that will work nicely, BUT be WARNED: that nail head will fly off with startling velocity. Wear goggles and be sure others are not around. Why they have so much energy when they break free I don't know, but they are dangerous.

I think you've got a choice of a quick and easy fixing with time taken to remove the fixing afterwards; or a more time consuming fixing that's easy to remove.

Personally, I'd choose the latter. Drill & screw the plate down, more time to fix but you'll take it apart beautifully.

Pre-drill slightly oversized holes in your trusses off site (zero site time). Use the type of nails that have a threaded top onto which you screw a nut. Mark through the holes. remove the truss and fire your nails. Return the truss then screw down with a power screwdriver. To remove unscrew the nuts with a the power driver and lift off undamaged trusses. Leave the nails in place to be covered by the screed. The small additional fixing time will be recovered in time savings on removal.

If you have already shot them down the only way to get your truss salvaged with out bending the truss is grind off thr heads of the shot nails. The metal in shot nails is realy hard.

I tried a new 4' ridgid bolt cutter on some Hilti nails once and it took the jaws right out of my brand new bolt citter

We use 1/2" hex head Powers fasteners for attaching structures to conctete floors. Palet wrack always needs to be re-cofigured. We have had pretty good sucess bing able to get them back out. Put some anti seze on the bolt. CAUTION use the Mfg drill bit.. All the Conctete anchor mfg's use a special dimention propriary to their system fo the drill bit to match the anchor. Use the wrong bit and you are in for roblems.

Worst comes to worse use a big impact driver and snap off hex heads.. no hex head on nails.

Have you try to drill the nail head off instead of grind it off?

I think I would use TAPCON'S. They go in quick, are easy to remove and have great holding strength. The pilot hole for going through the metal truss and the concrete is all in one step and you simply run in a TAPCON screw. You can install an additional washer or they may even have a screw with a large head.

Shot fired nails are intended to be permanent. However, as previous posts have said, you can grind the head off to remove your truss. If you place a sacrificial washer between the nail and truss you could minimize the damage from grinding.

That being said, I think you will spend nearly as much time and effort removing the shot nail as you would drilling and placing a proper concrete anchor. Maybe more, since drilling in a concrete floor with a hammer drill can go pretty quick. Plus, with a threaded connection you have some opportunity to tweak your positioning. This seems like an attempt to save time and cost on the front end that may cost you more in the long run.

Time cost of drilling hole = manpower + crane rental + crane operator

Time cost of grinding nail head = only labor & grindling consumerable

I drill holes and insert concrete screws designed for this. They come out almost as easy as they go in! Leaves a small 3/16" hole in the concrete.

Consider using nails with two coaxial heads, The first head holds your truss to the concrete, while the second head is for a pry-bar to either remove the nail or break it at the concrete surface.

4 1/2 inch disc grinder with a 1/16 metal cut off wheel. Get a cup type so you can flush cut. If there is a gap under the truss and the wheel will fit, cut them loose from the floor. The nails are really hard and tough steel, so a thin wheel will slice rather than grind through, less heat. Just cut the stub flush and leave it in the truss, it's practically welded in place.

"Just cut the stub flush and leave it in the truss, it's practically welded in place"

That's a FACT.

You don't say how 'thin' your truss is, if the metal is as thick as the 'nail' diameter, you will have difficulty removing it from the truss. If you don't want to damage it, you need to predrill the hole.

Experts never agree.

this is not just a joke.In real world experts never agree.

cutting or grinding off the nail head is best method.

take enough precaution to avoid accident.

Tapcon's are fantastic, if the slab is not more than a decade old or full of steel or radiant flooring. Get at least an inch in the slab. Drill it 1/2 inch deeper than the tap depth.

You did say light guage and temporary. Have you thought about a high strength velcro tape? similar to this

Tapcons work great for temporary fastening to concrete and no damage when removed. Just small hole to fill.

I have removed my fair share of these, I use a crowbar, a cold chisel, and a 4lb sledge...

You take the cold chisel and beat on the nail just below the head from one side to loosen it up, then take the crowbar to pry it out....you always take a divot in the concrete, but if you are resurfacing that's not a problem....

I hope Youngken hasn't been waiting seven and a half years for these clever answers on how to remove a nail.

No problem, sooner or later somebody comes along asking the same question....