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Do you mean just to drive them or how to install them in general? Use a hammerdrill to make the holes. Use a 3/16" drill bit for 1/4 screws(1/4 is most common size) or 5/32 bit for 3/16" screws. To actually drive them use the drill itself. Do NOT use clutch settings to drive them. Leave it it drill model but set it to the highest torque/slowest speed. You'll get a feel when to stop. Tapcons don't always go it consistently because of differing hardness and aggregate in the concrete. If the clutch kicks in halfway you'll need to back it out again or the drill will likely stall. If you have to back it out the threads will likely dig out around the hole and it will spin out when reinserted. You'll have to drill another hole. The ideal tool for them is actually an impact driver. Due to the nature of construction around here tapcons are everyday business for just about anything. With an impact driver I get about 95% tapcon driving success rate without damaging the hole vs about 75% with a drill driver. Oh and unless absolutely required, avoid using phillips headed taps. Always use hex head whenever possible.
I have had good luck with a Makita 12V impacting screwdriver and magnetic nut setter to fit the screws hex head. Impacting drivers have almost no torque reaction when you get to the end of the drive - just learn when to back off and there is very little, if any, torque reaction to deal with.
In addition, I've found that hammer drills and ordinary drills tend to wallow out the hole during the drilling process. I usually use an SDS drill with the correct size bit (you can buy these at Lowe's and I think also at Home Depot). These are much smoother drilling in concrete than regular drills. If you haven't tried one, it is amazing to see how smoothly and quickly they sink a bit into poured walls or floors.
Buy some extra bits - the first time you hit a piece of steel buried in the concrete, the carbide is toast.
Yeah, definately make sure to get a firm grip if using a drill to drive them. It can want to kick back pretty ferociously. An impact driver makes the process a breeze.
Personally though, I tend to avoid using SDS rotary hammers to drill the holes. They are too violent and tend to oversize the hole just slightly enough that tapcons don't grip well. The only time you can typically wallow out the hole with a hammerdrill is when drilling into the really hard stuff liked poured concrete. The tendency is to flex the drill bit around to force it to dig in. In these cases I will use the SDS with a one size smaller bit, then finish it off with the hammerdrill and correct size bit.
I guess it really comes down to finding the best combination - one that works the best for each user and situation. I've set lots of wedge anchors and red heads in poured concrete - attaching metal to slabs and garage door jambs to poured walls. I started out with the tapcon drill/drive combo tool and don't care for it that much. There is a similar kit for SDS drills and that is what I now favor - don't really have much trouble feathering the drill speed and I still feel that the SDS type drill gives me the best control. It seems to me that tapcons are kind of unforgiving - drive one part way or back it out to try a second time and the hole may be unusable. If the anchor is not going to be removed sometimes drive pins are a good alternative. There is also another drive anchor - basically a headed pin that has a small offset on the lower end that provides a good friction fit in the hole. I've also found that anchoring in cement block vs poured slabs/walls are two very different situations calling for different approaches.
Yeah driving tapcons is rather unforgiving. Once you start them off you need to commit all the way and get it right in one try. Its usually a good idea to have varying sizes on hand and always try to use the shortest length necessary for the task. If its too long then the threads wear out as they keep digging in deeper and deeper. If you wallow out the hole, drill the hole a little deeper and use the next longer size.
I agree driving them into block or poured requires different approaches. In block the go it quite easy but you need to be careful and not overdrive or you'll pulverize the gripping area around the hole. Poured is a lot more likely to actually damage the screw itself. The building I live in consists entirely of poured columns and walls that are so insanely hard driving tapcons into it quite literally crushes and flattens the the threads on the screw. They can't even dig in. I can drive them in but not out. They become a press fit but won't backout because they have to fuctional thread left.
Here is a trick, a little gross but it works. Spit (a healthy amount) on the tapcom before driving it for lubrication. It helps a lot. I'm sure there are other forms of lube to choose for the task but I can only vouch for this one.
A good carpenter makes few mistakes, a great carpenter can fix his own.