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3/8" hanger on 1/2" five piece bolt

Original Post
Karl Kvashay · · Phoenix, AZ · Joined Jul 2009 · Points: 225

I'm hoping for some opinions on this.

Karl Kvashay · · Phoenix, AZ · Joined Jul 2009 · Points: 225

1/2" hangers would have to be used with wedge anchors as the stud is 1/2", but five piece bolts have 3/8" studs. Sure, having the hanger rest on the sleeve would be marginally stronger(?), right? But then, I would guess a hanger with a smaller hole would be 'marginally' stronger

What's best?. What do you do?

M Sprague · · New England · Joined Nov 2006 · Points: 5,090

Use 1/2" hangers for 1/2" bolts. I know Fixe makes very good ones and has SS ones on sale atm for 1.95 each if you buy 100, which is a steal (normally $3 each for 3/8" or 1/2" SS. These hangers are very strong.

fixehardware.com/shop/sale-…

Using a 3/8" hanger would mean that you would have to remove parts of the bolt assembly ( the smallest ring on the shaft and the washer) in order for the bolt to be threaded well enough into the cone to not avoid potentially damaging the thread while tapping it into the hole. Those parts are part of the assembly for a reason.

Karl Kvashay · · Phoenix, AZ · Joined Jul 2009 · Points: 225

Thanks for replying.
So The expansion cone is well threaded even with a 3/8" hanger on my 3 3/4" cobra 1/2" 5 piece bolt. My main concern would be longevity of the stud. Using a smaller hanger, the load would be directly on the stud (like all wedge bolts)vs. a larger hanger where the sleeve would bear the hanger, perhaps protecting it?

Micah Klesick · · Charlotte, NC · Joined Aug 2013 · Points: 3,971

There should be no real strength difference, simply an assembly difference. As M Sprague said, you have to remove the small washer on the powers bolt to in order to seat the 3/8" hanger. I disagree however, that it will affect the strength. The ASCA sent all the bolts I've received with that configuration.

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
Micah Klesick wrote:There should be no real strength difference, simply an assembly difference. As M Sprague said, you have to remove the small washer on the powers bolt to in order to seat the 3/8" hanger. I disagree however, that it will affect the strength. The ASCA sends out all their bolts with that configuration.
There is a strength difference, I have verified it in pull tests. It's small, but pronounced.

Anyway, use a 1/2" hanger or just drill out the hole. It's easy as cake to drill the hanger out to 1/2". I have literately drilled out 50 hangers in under 10 minutes. There is no reason not to at least drill the hole out if needed.

Also, the Cobra anchor is not a five piece bolt. The Power Bolt, AKA RAWL 5-piece as it used to be called, is a far superior anchor. Further, you really should consider ditching those crappy plated steel Cobra anchors for real stainless steel ones. There is a reason why Power Bolts cost more. You seem to be concerned with longevity, so go the full distance and use 100% stainless steel. Dont use plated steel.
Greg Barnes · · Unknown Hometown · Joined Apr 2006 · Points: 2,065

Actually we try to send out all 1/2" hole hangers with 1/2" bolts, it's just that we're out (we've had 2000 1/2" hole hangers on backorder from Fixe for a long time - they have to retool to stamp "ASCA" in Spain, and half of the order are for tan powder-coated, and then they ship them slowly to the US…).

Only the 1/2" x 2.75" stainless Power-Bolts come with a small metal ring above the blue sleeve that you toss if using with a 3/8" hole hanger (this used to be a very thin blue plastic ring). The 4.75" ones do not and should not be used with 3/8" hole hangers since there's typically insufficient thread engagement.

M Sprague · · New England · Joined Nov 2006 · Points: 5,090
karl kvashay wrote:Thanks for replying. So The expansion cone is well threaded even with a 3/8" hanger on my 3 3/4" cobra 1/2" 5 piece bolt. My main concern would be longevity of the stud. Using a smaller hanger, the load would be directly on the stud (like all wedge bolts)vs. a larger hanger where the sleeve would bear the hanger, perhaps protecting it?
I was referring to using the Powers 5 pc, not other brands, since that it what I use. I wouldn't choose to use Cobras. You are using stainless, right?

Yes, I would think the sleeve would protect the bolt from the hanger if you use the correct size. I have seen stud bolts partially sawn through by the hangers that looked fine until they were taken out to replace with glue-ins (on Urban Surfer at Rumney for example), another reason I am down on stud bolts.
Karl Kvashay · · Phoenix, AZ · Joined Jul 2009 · Points: 225

Thanks for the input y'all.
Greg, since you are shipping out this configuration I have to believe that the strength difference 20kn is referring to doesn't approach "unsafe climbing". Unless, are you recommending that your donatees' drill these out to 1/2"? 20kn, I agree, a Cobra Sleeve pales in comparison to a Powers SS. Price difference is huge though, if the monies are tight. Is there any good documentation of plated carbon bolts "rusting" out in typical southern Utah climbing locations?

Karl Kvashay · · Phoenix, AZ · Joined Jul 2009 · Points: 225

I wouldn't consider using non-stainless on my home crags in Pennsylvania with humidity of 100% half the time, but in sunny So. Ut? The "local" climbing shop sells them, just sayin :) :)

Walter Galli · · Las vegas · Joined Sep 2015 · Points: 2,247

Any pics? Txs

Micah Klesick · · Charlotte, NC · Joined Aug 2013 · Points: 3,971
20 kN wrote: There is a strength difference, I have verified it in pull tests. It's small, but pronounced. Anyway, use a 1/2" hanger or just drill out the hole. It's easy as cake to drill the hanger out to 1/2". I have literately drilled out 50 hangers in under 10 minutes. There is no reason not to at least drill the hole out if needed. Also, the Cobra anchor is not a five piece bolt. The Power Bolt, AKA RAWL 5-piece as it used to be called, is a far superior anchor. Further, you really should consider ditching those crappy plated steel Cobra anchors for real stainless steel ones. There is a reason why Power Bolts cost more. You seem to be concerned with longevity, so go the full distance and use 100% stainless steel. Dont use plated steel.
Good to know. I stand corrected.
Micah Klesick · · Charlotte, NC · Joined Aug 2013 · Points: 3,971
karl kvashay wrote:Thanks for the input y'all. Greg, since you are shipping out this configuration I have to believe that the strength difference 20kn is referring to doesn't approach "unsafe climbing". Unless, are you recommending that your donatees' drill these out to 1/2"? 20kn, I agree, a Cobra Sleeve pales in comparison to a Powers SS. Price difference is huge though, if the monies are tight. Is there any good documentation of plated carbon bolts "rusting" out in typical southern Utah climbing locations?
IMO there is absolutely no reason for using Cobra bolts in a climbing application. I wish Fixe and ClimbTech would stop selling plated steel bolts... Bolts have been broken from rusting in pretty much every area. Spend the extra money, bolt wisely, and make your routes last for generations. I'm getting frustrated with the "It will last long enough, and then someone will come in and replace them for me" mentality. Just because the local shop sells them means absolute nothing. We had a local climbing shop selling a concrete lag anchor for climbing that wasn't even rated for pullout forces. Guess what, some developer bought them, used them, and we had two of them pull on whippers. The rest I rebolted as soon as I found out. Don't be that guy.
Greg Barnes · · Unknown Hometown · Joined Apr 2006 · Points: 2,065

Here's a photo for those who are wondering:

1/2 x 2.75" stainless Power-Bolt (aka 5-piece).

Red arrows point to the little metal spacer ring that you toss if using the bolt with a 3/8" hole hanger. On older stainless bolts of this size, the ring used to be a thin blue plastic ring (NOT the main fat blue plastic compression sleeve). Other sizes do NOT have this ring, and it's only with stainless bolts.

For the highly detail oriented folks, the pieces of the bolt left to right:
- blue plastic dust protector, to reduce junk getting in the threads of the cone
- expansion cone
- expansion sleeve
- blue plastic compression sleeve
- metal spacer ring
- washer
- plastic pressure-sensitive washer that tears out at about the right torque when used in concrete (it is often damaged or inaccurate in climbing applications, do not substitute for learning proper torque with a torque wrench).
- bolt core

For those wondering, the "5 pieces" of a 5-piece are the expansion cone, the expansion sleeve, the blue compression sleeve, the washer, and the bolt core. Longer bolts have another metal sleeve above the blue compression sleeve, and every once in a while people called those 6-pieces. For a while Powers made a short 3/8" plated version without the compression sleeve and some people called them 4-pieces.

Walter Galli · · Las vegas · Joined Sep 2015 · Points: 2,247

Ok now I got it, sorry im a newbie,, I will need some on my new route soon, txs

J. Stark · · Iowa · Joined Oct 2010 · Points: 649

I've seen plated bolts that were placed in the early 90s that have aged well. No rust to speak of. I think it all depends on the stone you're placing them in as well as the conditions the hardware will be subjected to.

I use 3/8" hangers with 1/2" power bolts. Works fine.

M Sprague · · New England · Joined Nov 2006 · Points: 5,090
Joe Stark wrote: I use 3/8" hangers with 1/2" power bolts. Works fine.
If not many people fall or hang on them they may be, but not such a great idea if people are whipping on to them regularly. Have you taken them out and looked at them to check and how would you know if you have weakened the threads on the cone?
J. Stark · · Iowa · Joined Oct 2010 · Points: 649

Yes these were heavily used bolts on popular routes. They were moved in favor of better placements during routine route maintenance. It was surprising to see old bolts such as these easily unscrew and look as good as they did.

It's also worth noting that these bolts were on portions of dry rock, not placed in dark streaks where water regularly runs down the face.

DrRockso RRG · · Red River Gorge, KY · Joined Sep 2013 · Points: 815

I'm with Joe. The majority of the routes in RRG are 3 3/4" plated rawls paired with 3/8" hangers. I have pulled around a 100 so far and haven't noticed any damage to the threads as a result of this pairing, the majority of these were on heavily trafficked routes.

DrRockso RRG · · Red River Gorge, KY · Joined Sep 2013 · Points: 815

I would be interested to hear anyone with legitimate reasons why there is anything wrong with climbtechs suggestion to use no washer and that 3/8" hangers are fine to be paired with 1/2" powers bolts.

"Product Description
Rock bolt hanger for climbing protection and belay, rescue, and rigging work; pascivated 304 stainless steel provides long life.

Smooth inside edges don't damage carabiners
Clip-in point big enough to accommodate 2 carabiners

Bolt hole fits 3/8" bolts or 1/2" full-sleeve bolts
No washer necessary for use with Powers bolts.
Dull matte finish to reduce visibility for a distance
CE/UIAA approved"

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346

In the case of the smaller 1/2" SS bolt, I would recommend what Greg said and remove the extension sleeve and just place a 3/8" hanger. The reason being that if you use a 1/2" hanger, it's going to fit over the crush sleeve and probably just destroy the sleeve on a fall. On the longer bolts, a 1/2" hanger will fit over the extension sleeve which is made of steel.

The main thing to consider is just make sure that there is enough thread on the machine bolt to penetrate the cone if you use a 10mm hanger. Not all lengths of Power Bolts match up correctly. Some lengths allow for more bolt penetration into the cone than other lengths. If there is enough penetration into the cone, I would still recommend using the washer if possible and feasible.

Typically speaking, the purpose of a washer is not to stop the material from being pulled over the bolt as many think. Rather, the main purpose of a washer is to stop the nut from cutting into the base material and fusing with the material, and to reduce the chance of the nut coming off by ensuring it binds to a smooth and even surface. Consider structural components such as lamp posts which are made out of inch-thick solid steel, bolted in several places, but with nuts on the bolts. Since bolt hangers turn after repeated whips, configuring a nut or bolt head attached directly to it is not the most ideal option. Using a washer is more likely to create a small buffer between the hanger and bolt head, thus allowing some independent freedom of movement between the hanger and the bolt.

Even giant nuts use washers:

Guideline #1: Don't be a jerk.

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