Seriously? Do you need a torque wrench for bolts?

kennyt wrote:where's the best place to buy hilti kb3?

Hilti has their own shops where they sell drills, bolts, epoxies, etc. Just say you want to do a cash sale.

hilti

I've placed around a thousand bolts and since I'm not too strong and I use a small wrench I don't worry about overtightening. I did worry for a while whether I was getting them right but an engineer assured me that it would be pretty hard to overtighten them with such a small wrench.

Dan Brayack wrote: I've placed maybe 400 bolt or so and every one of them, I've just tightened them as tight as I could. I was under the impression that torque and bolt tension have no direct correlation <3 -Danno

Wow man, want to share where these bolts are so I can avoid them?

Every box of bolts I have ever bought come with a spec sheet. Most Hilti 3/8 stud style bolts require 20-30 ftlbs of torque. A small girl can apply that much one handed with a typical 10 inch long wrench. A wedge style bolt does not need much torque to be strong. Even a totally loose stud (that was pre-torqued initially) has 100% of it's strength, by design. Falling/pulling on them engages the cone, the initial torque mearly starts the cone and holds the hanger from spinning. When you overtorque a bolt, you can usually hear/feel a small pop as the cone snaps inside the hole. This is how I remove bolts for replacement, and it is not hard to do with a hand wrench!

I've heard 5 piece bolts are even more sensitive to torque and they DO require some torque to work. This is why they are removable. You can't loosen a stud and remove it like a 5 piece.

Like others have said above, get a torque wrench and learn what 30 ftlbs feels like. You will be surprised how soft it really is! Please don't tighten them as hard as you can!

Dan Brayack wrote:Its interesting now, that we're all using stainless bolts that spinners are becoming a major problem...before, the threads would just rust and the bolt wouldn't spin unless it was really jacked.... I've learned with the bolts I'm using that i crank it down to "flush" - the twist until it pops a few times - I have a "happy spot" with my wrench where I'm not crushing it, but I'm giving it a good pull...of course, if I'm hanging upsidedown - all bets are off :)

Oh geeze, That pop is exactly what I described above... the cone snapping internally.

Again, can you please tell us where these bolts reside?

joeforte wrote:Like others have said above, get a torque wrench and learn what 30 ftlbs feels like.

Note that the maximum torque for 3/8" stainless steel Power-bolts is 12 ft-lbs, and for 3/8" carbon steel Power-bolts the maximum torque is 25 ft-lbs.

When rap bolting, I now exclusively use a torque wrench; however, before I started using the torque wrench I followed the Power-bolt non-torque-wrench instructions, which are: "Tighten the anchor 3 to 4 turns past finger tight."

(When bolting on lead I use stainless Fixe wedge bolts, and I don't use a torque wrench.)

People aren't using torque wrenches! We are all going to die! More Crap to f#@% with your mind. Zillions of bolts, no torque wrenches and I have never had or heard of a modern 3/8th carbon or stainless bolt breaking. Go climb, have fun, don't worry about it for a second! Oh yeah and don't crank on them til your eyes bulge.

Larry, sorry I meant diameter - sometimes brain function isn't so properly in the morning :)

Yeah - I think that you guys are really going overboard on this...bolts aren't going to fail because you over tighten them and none of my bolts are going to fail...no matter how hard I tighten them - the major concern of mine using stainless bolts is that they'll become spinners...which is a pain in the butt because I'll have to tighten them down again...or worse, a hanger will fall off...

I'm also really surprised how technically precise every seems to be commenting - placing a bolt is easy but not necessarily the best place to "make sure you 30 ft-lb force on the nut" - half the time I'm hanging upside-down in a roof reaching as far as I can with the wrench trying to tighten down the bolt...well maybe 10 percent of the time...I just wonder how many people actually are this precise with their bolt placement.

I'm pretty sure that the breaking strength on a bolt is so high, over torqued or not, that its not going to fail the steel of the bolt....Have you guys ever heard of a bolt breaking that wasn't a rusty spinner (at least in the stuff we put it in here) - I haven't...and there are some pretty scary old bolts here at the New River Gorge.

If you're worried about bolts being over tightened, then don't come to the new - you'd be safe off... :)

oh and the comment about the bolt breaking off when I hear a pop - I have broken off some 5 piecers (old bolts to be replaced) and then do in fact, break off down in the hole, but the wedge bolts always snap off right at the surface.

<3

-Dan

What is your favorite torque wrench?

Also, what is your recommended product to keep nuts from spinning in the future?

Dan Brayack wrote:If you're worried about bolts being over tightened, then don't come to the new - you'd be safe off... :)

So these 400+ bolts have all been at the New? What areas?

Multiple folks have asked you this question because it's very important to them so please do us a favor and honestly tell us where these bolts have been placed.

cheers,

Morgan

Dan Brayack wrote:...I've placed maybe 400 bolt or so and every one of them, I've just tightened them as tight as I could... -Danno

that's a little scary.

edit: having read your later posts, i'd say it's a lot scary. please let us know where you've put routes in so we know what areas to avoid.

Dan Brayack wrote:...none of my bolts are going to fail...

None of them? Not even the one that did pull out?

If you read the article, you'll see that that bolt wasn't even tightened down and was on a closed project.

Dan Brayack wrote:If you read the article, you'll see that that bolt wasn't even tightened down and was on a closed project.

So Dan, what areas specifically have you been bolting? If there's nothing wrong with what you are doing you should have no issue responding with details.

Somehow you seem to be ignoring this question posed to you by many people on the thread... Are you too much of a coward to actually respond or are you afraid you'll be held responsible if something happens to someone or are you just making this thread up?

Dan Brayack wrote:If you read the article, you'll see that that bolt wasn't even tightened down and was on a closed project.

I did read the article. I also read the accident report on the Appalachian Mountain Institute's web site: appalachianmountaininstitut…

An interesting excerpt:

"The excessive marks on the bolt, hanger and nut, plus the threads not working may have been an indication that the bolt had too much resistance while being driven into the rock. The damaged threads appeared to have caused the nut to lock down before the collar on the wedge was fully engaged. It appears as though the collars were, however, partially engaged, which might have added to the illusion that the bolts were solid.

There are several additional questions that need to be analyzed. The first of those should address the bolt installation. Was there added resistance with the bolt’s installation? If this is true, how old was the drill bit and was the bit’s diameter still acceptable enough to drill a quality hole? Was the bolt simply hammered too hard or too irregularly? What damaged the threads?"

Elsewhere in the report it describes damage to other bolts on the route.

The point is that someone has been injured as a result of your bolting practices. And, yet, you have the hubris to hop online and spray about how you knowingly disregard the recommended specs and brag about how none of your bolts are ever going to fail.

My 2cents:
Being able to afford a drill has never qualified anyone to use one.
Bolts come with spec sheets in every box. I've known only a few who actually use a torque wrench. I use the "watch the tendon on my wrist" method. Takes years of practice though. 2.5-3.5 turns past finger tight is the spec for not using a torque wrench.

Good thread so far, though things seem to be be heating up for some. Let's keep it easy folks.

John Wilder wrote:It seems to me that torquing blindly is foolish- lives are being trusted to the bolts people install and they should at least spend a bit of time learning what proper torque on a given bolt feels like. I used a torque wrench for awhile, and am always VERY careful on 3/8" SS bolts, as I have snapped one or two, as have many of my friends, while tightening them. I even snapped a 1/2" carbon bolt once while tightening it with a torque wrench- it snapped just below its recommended torque. at any rate, Dan, you know your area better than I, but if the New is as hard/solid rock as i've heard, over-torquing your bolts there could be pretty dangerous- the one bolt I broke torquing to spec was in the hardest rock i've ever drilled in red rock, felt like granite.

Wow! You guys must have really big wrenches or are MUCH stronger than I!

I bought a torque wrench long ago to figure out what 20ftlbs feels like because I am anal about such things...but this thread got me to thinking.

So, I thought I would over-torque some bolts. I tested a Fixe 10mm carbon wedge and a few Hilti Stainless 3/8" wedges. I started out by tightening to "feel" with my regular wrench and then tested that with a torque wrench. Each time it came in a tad under 20ftlbs.

I tightened the Fixe to 40lbs without issue and pounded it out (I had it in a cobble.)

I then tried a Hilti and did the "feel" test to right near 20lbs and then tightened it with the torque wrench to 40lbs which broke the cobble...see pic1.

I tried another Hilti with the same results...see pic2.

I then dropped a Hilti into some concrete outside and "feel" tightened to right at 20lbs and then tighted it to about 55lbs with my torque wrench where there was a noticable "slip" (I think this was the stainless actually turning internally; "bending" if you will; or maybe it is the bolt rotating in the hole while the wedge stays still?; is this the "pop" Dan describe's above..that's a scary thought! These are wedges too.). I then stopped and felt the bolt and it was HOT to the touch. I reattached the torque wrench and the bolt "slipped" a couple of more times as I tightened it all the way up to 70lbs where it sheered off (see pic3). The bolt was VERY HOT at this point...see pic 3. Sorry its blurry...but it is a sheared stud with the nut virtually welded on.

Recommended max torque on the Hilti is 20lbs.

I recommend everyone tightening bolts learn the "feel" on a torque wrench...but man am I amazed you guys are shearing bolts with a small wrench. You must be wailing on them! Lighten up, these are expansion bolts...not your truck's lug nuts (which are torqued at 80lbs).

Dan's "tight as I could" is certainly too tight for most bolts...but I am amazed that people are applying over 40lbs with a small wrench. Of course...it's not the sheared bolts you have to worry about...it's the ALMOST sheared ones.

Regarding the NRG bolt-failure noted above...these bolts did not shear..they pulled and had some thread damage and the like. Did anyone determine if they were 10MM bolts pounded into a 3/8" (9.5mm) hole? That could damage the cone, wedge and threads.

What is your favorite torque wrench?

What is your favorite torque wrench? I just use a standard needle wrench. I bought two different types and they are consistent. 

breaking wedge bolts (or similar) isn't as common as snapping the powers style bolts.