Vicious star-bit injurs, Impact nasty…
Wow, hubby really got hammered good today! He was using the impact driver to drive some screws into the new deck, #8 star drive, stainless. One side of the bit tip fractured off and then the tool, still impacting away, jumped off the screw and bit went into his thumb just barely below the cuticle. Ouch! the pad side of his thumb is badly bruised, and it’s hard to tell just how far the bit went in.
I wasn’t here when it happened, or I’d’ve sent him to the doctor’s office. First thing tomorrow.
Is that kind of bit fracture common under these circumstances? He had another one break (pre-drilled Ipe, yes it’s HARD). That one was a longer fracture and it’s wicked-sharp. Wish I’d know, we would have had that “Watch where the other hand is” conversation!
forestgirl — you can take the girl out of the forest, but you can’t take the forest out of the girl 😉
Replies
I winced at your description. Not life-threatening but really nasty just the same. He should get it looked at professionally, just to keep it from infecting...
Those bits do break fairly often, especially if you're working something like ipe. I'd say that you could expect it to happen once every few hours, so you've got to develop work habits that include keeping the other hand away.
I'm afraid this lesson was a costly one.
David Ring
http://www.touchwood.co.il/?id=1&lang=e
OUCH!!!
Been there, done that. Hope he's OK. It is fairly common to have tips break like that. Often times the tip is the weakest link especially with larger screws into that super hard material. A hard lesson to learn.....
-Paul
FG,
I was reading quite recently (can't remember where, might have been an on-line tool catalogue) an article that was all about pre-drilling before screwing. The article pointed out that the general rule of "pilot hole 1mm smaller than screw diameter) for hardwoods is too crude. Some hardwoods (perhaps that ipe) are so tough that 0.5mm or even 0.3m difference between pilot hole diameter and screw diameter is appropriate.
Also, it depends on the nature of the screw's thread, as some modern screws are made with super-thin but very hard/sharp threads to cut into anything without needing so much force. Traditional screws have fatter threads that don't cut very well (brass being the extreme example perhaps).
Of course, there was then a reference in that article to sets of drill bits that go up in 0.3mm steps insted of the usual 1 or even 2mm steps. That can be quite a few drill bits......
Lataxe
I don't see any advantage to getting any thread bite in the ipe. On a hard wood like this, that would prevent any draw-down from the screw head when it reached the deck, if a board was warped up, and needed to be drawn down. I think it would be much better to have an oversize pilot hole, so all of the thread bite was in the framing wood. It sure would make for easier screwing too.
Keith,I'd assumed the substructure under the floor that's being screwed into was also ipe. I suppose it may be something else, although presumably it too will need to be durable.But you're absolutely right about not needing to screw into the deck top itself.Still, I did think the general point of that article I read was logically sound - different timbers will need more or less "wall" for a screw to grip and the "more or less" must depend on both the nature of the wood but also the mechanics of the screw. If the force necessary to get the screw into the wood is very large (because too small a pilot hole is made) then there's a danger of the weakest part of the drive-chain going - the bit, in the case described by FG.Lataxe
The substructure is TP lumber. The pilot hole was made slightly bigger than the threads (very slightly) so that the fin-trim head would countersink without any problems.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Keith
My best results with Ipe came when I pre-drilled a pilot hole the same size diameter as the screws I was using. The flathead screw head was plenty sufficient enough to hold the board down, and the Ipe is so danged tough that there's no way the head is going to work it's way through the wood.
So, in short, I agree with you....ha ha.....
Jeff
Yea, Jeff, When you think about it, Gravity would probably be enough when you are using a wood like that. ha
Hi, Lataxe. These are GRK stainless self-drilling screws, for which we made pilot holes anyway because the Ipe is so hard. The first dozen or so we put in went in just fine, but there was no backing them out. So we increased the drill size by a tiny bit (pun intended). I used calipers to decide where to start size-wize.
The bits are from GRK also. I was warned in advance that the bits would break (Breaktime folk, another pun). So I had them toss a half-dozen in the order. I didn't think in advance about how the scenario might play out!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Jamie,
The GRK screws are super good: however, the GRK driver bits sometimes leave a bit to be desired (uug...). Don is right about better drivers. I have had very good luck with the APEX brand of driver, also.
-Jerry
In most cases I drill a shank hole in the one material being joined and a pilot hole in the other piece. That is, the screw should be able to pass freely through the Ipe and thread into the joist.
I bought an impact recently and had a bit break right off the bat. The bit I was using was a Philips about 1/1/2" long that was hardened.
This just doesn't happen to me with normal drills. So now I am more careful with the impact.
One other thing I tried was to use an extension bit holder. The kind that you put in your drill that are around three inches long. They have a magnetic tip or a little spring inside that holds your short bit.
I figured the extra length of the extension that wasn't so hard could absorb some of the shock. Also, if your short bit in the end broke it is less expensive.
Hi, Wheelie. The star bits from GRK are full-length bits, so there was no extension. Earlier, just before I left him to his doom, we had stuck an extension with a small Phillips bit in it for some other driving. Interesting thought about the extension absorbing some of the energy.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
I beleive that they do make impact rated driver bits. An internet search would probably turn up several makers.
The ones that come to mind immediatly are made by Dewalt and come in a kit of several bits and nutdrivers that are impact rated. I found mine on Amazon doing a search for impact rated driver bits iirc. I have also seen the kit at Lowes, don't know if it includes a star bit. The bits in the kit are finished black, often in the auto industry impact rated sockets and extensions are finished in a black oxide type finish rather than chrome.
You might have just had a cheap bit, I have broken a couple bits at various times. I have had good luck with bosch bits available at Lowes. The driver guide that the other poster mentioned would be a safe alternative to holding the screw, but you feel like you give up some control.Webby
"You might have just had a cheap bit..."Not necessarily. Bosch phillips bits are great for gripping even when angled a little and their tips resist wearing down in use, but they break easily when used in an impacter (package label even says not to use in impact driver).Cheap Irwin bits may get chewed up if allowed to skip, but have never broken on my impact driver. Maybe harder steel is too brittle for impact.BruceT
The soap thing work well, I've used that aid myself. But in this situation, hubby is a very impatient soul, could never get him to do that. But the other thing is, Ipe is kinda waxy itself. The drill bits get this waxy deposit on them. Weird stuff.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Normal bits will crystalize and fail when used with an impact driver.
McFeelys has impact rated driver bits in the catalog. http://www.mcfeelys.com/impact-driver-bits
Thanks for the link, Jigs. I had been planning to check McFeely's for bits, but since the fastener folk had the GRK bits in stock, I just went for them. I think I'll order some stuff from McFeely's just to have around.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
It’s not just impact drivers but I’ve, I mean a friend has pushed a few bits into my, I mean their fingers over the years. The last time I, I mean my friend did this I got, crap I mean he got full penetration thru his left index finger.Of course my wife wonders, I mean (darn it) his wife wonders about him and work as he managed to slice his fingertip off with a block plane.
You...your friend needs to be more careful! The truly frightening part about running a bit through a finger is how easy it is for that bit to find bone. Chances of getting an infection in said bone are pretty darned high, and hard to treat. Quite painful too. And then there's the possibility of going through a joint. Not to be contemplated!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
That is very possible. However I have a dewalt 12v impact and a makita 14.4 I regularly use bosch bits, and in the past three years have broken one bit, maybe two.
I don't worry a whole lot about it, I buy what is readily accessible at the box stores for a variety of projects. I haven't had enough of a problem to make me change. My attitude was based on my experience. I think Bosch bits or Dewalt bits are decent quality.
I avoid the loose no name bits at the hardware store in the fishbowl. That is what I meant by a cheap bit. Maybe FG was using a good bit and just had a bad expereince. That is why I recommended the Dewalt bit set rated for impact use to her.
I haven't had the chance to try some of Mcfeelys bits but regularly use their services.
Webby
One of Makita's finder/drivers helps a lot. I recommend the "shorty" for the impact application because of its steel shank. The sliding sleeve covers the bit and the screw during the entire driving process, if the bit or screw breaks everything is contained within the sleeve.
If you can find some Enderes brand bit's I think you will have a lot less breakage.
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Men will never be free until the last king is strangled with the entrails of the last priest.
~ Denis Diderot
Don, I think our Lumbermen's carries those bits. At least I've seen bins like that there. I have a driver/finder but wouldn't that obscure our view of the screw as it's driven? We have to stop the impact when the screw gets just a tiiiinnnny bit under the surface of the board. I think I have a d/f that's clear plastic, we could try that.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Really sorry. Don't forget the tetanus shot.
Frosty
"I sometimes think we consider the good fortune of the early bird and overlook the bad fortune of the early worm." FDR - 1922
Yep, he's going in this a.m. to see doc. Thanks!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
As others have said those bits break often, but most of the time without injury. One suggestion I would make is gloves. I use them now definately on construction projects. While not a garantee, the leather tips can absorb a lot of punishment that normally would happen to skin. The good ones are not cheap, about 20$ a pair but they are worth it. When feeding stock through the ts I like the neoprene ones with antislip surfaces. BTW I don't consider gloves push sticks still use the grippr's. Good luck on the deck.
If it moves, tax it. If it keeps moving, regulate it.
And if it stops moving, subsidize it.
He wears gloves most of the time he's working (leather), but no way to grip those thin-shank screws with a gloved hand methinks, at least with any glove that would be substantial enough to protect. I think he just needs to place his left hand a little further away once the screw is started, and maybe not press so hard with the driver -- he has a hard time doing anything with a power tool without "horsing" it. His subconscious thinks everything takes much muscle-power assistance. This would be why I hide some of my tools, LOL!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
FG ,
Very sorry to hear about your husband's injury. It sounds pretty nasty. Nothing like putting all the force of a tool to work, and then having that force directed into soft body tissue. Pretty cruel..
I've had several driver bits break off, and I've never even owned or used an impact driver. It's a pretty common thing when driving concrete screws. I think the force is just too much for the slim diameter bit, or the bit tip, to take. An impact driver might make the problem worse because of the sudden "shock" when the impacting spring inside the tool loads all that force onto the bit all at once.
Reading your story made me curious about whether there are specialty bits designed just for use on impact drivers. I know there are heavy duty and shock-resistant sockets made for impact wrenches, but I've never seen or heard anything about something similar for impact drivers. Maybe because they're still relatively new to the market this is an issue that hasn't received much attention yet. But, as your husband discovered, maybe it should...
Zolton
If you see a possum running around in here, kill it. It's not a pet. - Jackie Moon
I think some bits are designed more for impact drivers, something someone wrote when I was asking for tips on buying an ID. I bought an "impact set" by DeWalt for regular bits, also included extensions, a few nut sockets, angled driving gizmos. Haven't looked enough to know whether some bits are labelled driver-type.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Hey Forest, Sorry to here about injury. I have recently pushed a Philips into my left index finger, ouch and not the first time.
Dewalt makes impact ready bits, IMO they just do not break as fast as standard bits. Pre-drilling should eliminate tip failure for the most part. Sounds like the star bits are not meant for impact use.
Hope he heals quickly, Tom.
Forest.. I hope your Mate is OK!
Forest.. I hope your mate is better than just OK and heals as well as at least I do. As in I heal really quick even at my age..
I have built more than a few decks and other 'house' things in my life. In my opinion.. A standard drill with a torque setting is what he needs. NOT an impact drill! OK if it has a torque setting AND IF he USES IT!
That must have hurt! ALOT!
I would think he should have gone to the hospital immediately.. But if it was me, I would not go the hospital until my finger turned black..
All of those bits are sintered metal. (I think) STRONG but will SHATTER on a sharp impact. Which a impact driver does!
I could be very wrong. I am SURE somebody will get on my case if so.. I do not think sintered metal is made for impact driving.
Anyway. I learned to hold the screws with a V shaped block of maple. Back it off as the screw really got stared. Saves fingers!
I don't know if this would help, but someone a long time ago told me about applying soft bar soap to the screw for a tough drive. It has helped me in using long screws in tough situations. I am not familiar with the type of wood you are using, but it might ease the strain on the driver.
Dennis
I first came across this type of screw about a year ago. On one contract the contractors were using them to attach 1mm stainless sheets to a subframe of 2 - 3 mm steel. On another contract they were used to attach an aluminium/insulation sandwich cladding to a steel structure (a 10,000 pallet warehouse).In each case I note that the "top" layer is relatively weak and can strip easily. I have used these screws once myself, to attach 3/4" plywood to a steel frame. Again the top layer was easily strippable.I am not familiar with IPE but from what has been said here it must be very tough. Would it not make sense to predrill the IPE for a full clearance and not bother with a pilot hole for the frame as the bolt will then chew its way in?
Ipe is tough stuff, yes it is. Super-dense. We're not pre-drilling the frame. Technically, the hole is bigger than the screw, but there's still some drag on the bit.
We're down to just a few boards for the back steps, then this part of the project is done. Yipee!! Will have to put in balusters and railing, and then it is a done deal.
Thanks everyone!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Beware of cheap bits. I bought a bargain pack of bits once and it seems they were overhardened (brittle). I broke with some regrinding, they make nice drill bits.
Chris @ www.flairwoodwork.spaces.live.com
- Success is not the key to happines. Happiness is the key to success. If you love what you are doing, you will be successful. - Albert Schweitzer
i didn't read most of the replies so this may have already been said but those grk bits are garbage. i've used the screws many times on trex decks and i have broken countless bits. If you are using the same screw that i have driven thousands of then a T15 torx bit fits. You can find decent ones that break less for alot cheaper than grk bits.
Not really sure what a good bit is. I have a Bosch driver (the little itty bitty guy) that is not an impact and I have broke two Bosch bits in half in the last 6 months. I bi#$$ed to the Bosch rep about this at a local wood show (while holding another Bosch tool in my hand I was thinking of buying and talking about various Bosch tools I own and his reply was "that happens" I pointed out that I am used to stripping them out but not breaking then in half, and got no place. So being annoyed with this reply I put down said tool and walked off. I mean I know the little guy has power and all but to break that many bits? I must have done this on this tool at least 5 times in the past year (only owned it about 15 months) Maybe it is an undocumented design feature so you do not break a screw? :)
Doug M
My guess on it breaking in the middle is that the tip is hardened, and the shank isn't as hardened, so it crystallizes on the boundary and fails.
Just an educated guess, I'm not a metallurgist, but I did have couple of classes dealing with it in college.
Just making an educated guess again: I would expect the bits that are hardened and then cryo treated would be the least susceptible to breakage, and wear.
At least for Philips tip bits, I've had pretty good luck with the DeWalt bits - bought a pack of 6 or so, and I think I may have broken 1 or 2 and worn out 1 or 2.
Prior to that, I went through several Bosch bits, a couple of which only lasted for a couple screws - definitely not designed/manufactured for impact toughness.
Someone mentioned the extension holders. While it may reduce the shock somewhat, the shock (impact) is what the impact driver is for - short hi-impact shocks drive the screw with much less average torque on the screw and operator. I've used the magnetic extension holders when I either wanted to switch bits quickly, or had the short bits which wouldn't go directly into the driver. Problem is, the magnets and/or the glue holding the magnets are brittle and fail quickly in impact use.
Don
I've not had that problem with the Makita short extension I specified and some of mine are well over 8 years old. As to the problem of not being able to see the screw while driving, I've found I can be very accurate by listening to the sound. Others mileage may vary using this method.
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Men will never be free until the last king is strangled with the entrails of the last priest.~ Denis Diderot
"Others mileage may vary using this method." No kidding!?forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
You might be surprised how accurate you can be using sound!
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Men will never be free until the last king is strangled with the entrails of the last priest.~ Denis Diderot
I will bet you lunch at any restaurant in my town that on the second try you can fill a glass to a mark using only your ears.
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Men will never be free until the last king is strangled with the entrails of the last priest.~ Denis Diderot
Will you take that bet on Nick? Hah, hah, hah!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Yep, I'll still take that bet, and needless to say lunch for three (me being one)!
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Men will never be free until the last king is strangled with the entrails of the last priest.~ Denis Diderot
Who knows, now that gas prices have descended from the stratosphere, we might be able to cruise up your way again! After Christmas, LOL. Haven't been up to see Dennis in a long while, and he and his LOML have two new dogs!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
I have a Jack Russell, but he's not very sociable.
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Men will never be free until the last king is strangled with the entrails of the last priest.~ Denis Diderot
Don,That wee tyke is The Very Dog for thee! I am getting a mental picture of you now via my "forum post pictorial analyser & extrapolator". So far it shows a small but handsome chap of a vigorous mien and some sharp teeth, which may be smiling or performing less pleasant social operations. :-)****Being the tool junky-boaster-gloater I am, subliminal messages (not that subliminal) have been laid in the ears of the family concerning an impact driver and its absence from the shed. I'm hoping Santa will be reading this thread afore he sends an elf down my chimney.Lataxe, admirer of many Yorky thangs.
Cute!! You have my awed respect at being able to live with a Jack Russell. They have waaaayyyyyy too much energy for me!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
I know that had to HURT , most of the bits that you by over the counter are not designed to be use in an impact gun. Snap-On tools makes bits that are made to be used with an impact gun (expensive) but I have not had one shatter on me I have twisted them but not shattered any, one good thing if it breaks or twists I just hand it to the distributer and he gives me a new one, no questions asked. hope hubby had the deck finished so he can sit back and enjoy his handy work while he is mending
He's mending pretty quick, med. He finished the back steps yesterday. Picking up the balusters this afternoon. We're so lucky it didn't go too deep into his finger. Interesting thing about the tentanus vaccine -- doc say that at his age, Nick's had enough boosters he pretty much has permanent immunity to tentanus.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
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