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Climbing bolt strength requirements

Original Post
Dood · · Chattanooga, TN · Joined Feb 2012 · Points: 370

Can anyone tell me where to find cheap 3.5" 3/8 SS climbing bolts?

For reference, the bolts I was asking about before I got flamed.
cacheoutdoor.com/climbing-4…

fat cow · · St. Paul, MN · Joined Nov 2009 · Points: 10

probably not.

Christopher Barlow · · Unknown Hometown · Joined Dec 2006 · Points: 540

Since when is a bolt's tension strength higher than its shear strength? I think you got those confused. More importantly, if we assume you did switch the two, the number for the tension strength seems pretty low proportionally to the shear strength.

Furthermore, from where did you get those numbers? They don't match anything on the Powers Fasteners website.

To simply answer your question rather than poking holes in it: Yes, those numbers are plenty high for climbing use.

That said, (and I cringe to even go there since it's so obvious) this seems like a case of "If you have to ask, maybe you shouldn't do it." You're from Chattanooga; there are several folks who have sunk hundreds of bolts into that sandstone and can give really good, specific guidance about the best hardware to use.

Eric Fjellanger · · Unknown Hometown · Joined May 2008 · Points: 870

Please go here and read everything

safeclimbing.org/education.htm

before even thinking about drilling a practice hole in a crappy scrap chunk of rock.

Dood · · Chattanooga, TN · Joined Feb 2012 · Points: 370

My hangers are 10mm so the triplex would not work.I thought fixe 3.5" 3/8 wedge bolt anchors were pretty much the standard around here. I know that some local bolters use them even though other bolts have better ratings. The best anchors in testing seem to be glue-ins but I don't see any around Chattanooga.
Leftwich, don't worry I'm not going to bolt any trad lines at sunset, or anywhere for that matter.

ABB · · Unknown Hometown · Joined Mar 2007 · Points: 0

There is no such thing as 'cheap' stainless steel bolts for climbing applications. SS is expensive. No getting around that. Most suppliers only sell boxes of SS bolts, the minimum quantity being 50 per box. Typically only climbing shops sell them individually.

Wedge bolts are very difficult to remove. They must be pried out, which often takes a chunk of rock with it, leaving a small crater, and then requires that a new hole be drilled. Or wedge bolts can be snapped-off, which still requires a new hole come replacement time. The Rawl 5-Piece, as Fixe refers to it, is a sleeve-style bolt and is easier to remove for inspection/replacement. This bolt is made by Powers Fasteners, referred to by them as the Power Bolt (1/2" x 2 3/4" SS, Powers part #05930). 1/2" is also becoming more fashionable than 3/8".

Presumably your hangers are stainless so you won't be mixing metals? Bolting/re-bolting, as you well know, bears a big responsibility and must be done right not only for today but for decades to come. Thanks for doing it right!

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
ChillFancy wrote:Can anyone tell me where to find cheap 3.5" 3/8 SS climbing bolts? For reference, the bolts I was asking about before I got flamed.
Those bolts are safe to use in climbing, however if they are safe for your application or not depends on your local environment. Those bolts are carbon steel, I would suggest getting stainless steel. If you are going to use stainless steel hangers you must use stainless steel bolts. The wedge bolts you linked to can only be used in hard rock. Do not use them in soft rock. Anyway, I suggest shadowing some of the bolting experts in your area, bolting is an esoteric topic that demands quite a bit of knowledge in the area. It is pretty easy to screw up a bolt placement, and if you do, you can get someone killed. Also, if you do place these bolts, drill the hole deeper than the entire length of the bolt! Eventually those bolts will need to be replaced. Well, wedge bolts cannot be removed. So the best option is to pound them deeper into the hole so they are flush with the rock. However if you do not drill the hole deeper than the length of the bolt, this will not be possible.
20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
Christopher Barlow wrote:Since when is a bolt's tension strength higher than its shear strength? I think you got those confused. More importantly, if we assume you did switch the two, the number for the tension strength seems pretty low proportionally to the shear strength. Furthermore, from where did you get those numbers? They don't match anything on the Powers Fasteners website. To simply answer your question rather than poking holes in it: Yes, those numbers are plenty high for climbing use. That said, (and I cringe to even go there since it's so obvious) this seems like a case of "If you have to ask, maybe you shouldn't do it." You're from Chattanooga; there are several folks who have sunk hundreds of bolts into that sandstone and can give really good, specific guidance about the best hardware to use.
Actually, in the case of wedge bolts, 1/4", 3/8", and most 1/2" wedge bolts are actually often stronger in tension than in sheer (although you should check the tech specs page to be sure). It is not until you are dealing with 5/8" and above diameter wedge bolts that the sheer strength is higher. When you are talking about sleeve bolts, or most glue in bolts, the sheer strength will normally be higher.
Dood · · Chattanooga, TN · Joined Feb 2012 · Points: 370

I keep hearing good things about these.

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
ChillFancy wrote:I keep hearing good things about these.
Yes, the Power-Bolt is the strongest 1/2" expansion bolt on the market when loaded in tension. They are great bolts. Often times you can find a super good deal on them on eBay. Not that far back I picked up 75 of the 1/2" x 3.75" ones for $40 on eBay. Those bolts can be used in both hard rock and soft rock. Technically they are not designed to be used in rock with a compressive strength below 2,000 PSI, but the rock in Red Rocks is often below that and the bolts seem to hold fine there. However, if you are bolting in very soft rock (below 500 PSI), you should only use glue-in bolts.
M Sprague · · New England · Joined Nov 2006 · Points: 5,090

Wow, nice deal on those 1/2" Rawls! I use 1/2" SS Rawls too. I am a little wary about getting them off EBay though. It seems like there could be more chance of them being some cheap Chinese counterfits. Did they seem to be the same quality, and were you able to test any of them?

In sandstone, even the really nice hard southern stuff, I would go with 1/2" ers (glue-ins even better), especially on a popular crag. It seems like they don't loosen up and become spinners nearly as much as the 3/8" ones, as well as being stronger.

M Sprague · · New England · Joined Nov 2006 · Points: 5,090
ChillFancy wrote:I keep hearing good things about these.
Make sure you get the stainless versions though (yeah, they are expensive)

I wrote to that retailer encouraging them to only sell the stainless versions. I hope others will do so too. Carbon ones are only passable in the driest environments.
Dood · · Chattanooga, TN · Joined Feb 2012 · Points: 370

Thanks for everyone who sent me helpful comments, and to the SCC for the information on their bolt requirements. SCC req is 3/8 stainless expansion bolts in 2.5 (for hangers) and 3.5 (for top anchors.)

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
M Sprague wrote:Wow, nice deal on those 1/2" Rawls! I use 1/2" SS Rawls too. I am a little wary about getting them off EBay though. It seems like there could be more chance of them being some cheap Chinese counterfits. Did they seem to be the same quality, and were you able to test any of them? In sandstone, even the really nice hard southern stuff, I would go with 1/2" ers (glue-ins even better), especially on a popular crag. It seems like they don't loosen up and become spinners nearly as much as the 3/8" ones, as well as being stronger.
Yes they are legit. I doubt anyone is trying to create completely identical Power-Bolt knock offs. Plus they came in a box with Power's logo on them and the seller had thousands of feedback points. But they were not SS. It seems SS Power-Bolts are really hard to find on eBay. But it does not matter for my application, I only use the Power-Bolts for temporary or noncritical applications.
20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
ChillFancy wrote:Thanks for everyone who sent me helpful comments, and to the SCC for the information on their bolt requirements. SCC req is 3/8 stainless expansion bolts in 2.5 (for hangers) and 3.5 (for top anchors.)
I assume you mean 2.5" for lead bolts and 3.5" for the anchors? Why do people seem to think the anchor bolts are more important than the lead bolts. Let me expose a few truths about this. First off, the lead bolts generally see much higher forces than the top anchors do. Second, the lead bolts are often times nonredundant, the anchor bolts are redundant. I have been 70' off the ground at the RRG and only had one bolt between me and the ground, risking a 40-50 footer on that bolt. I don't know why some developers think it is really bad for an anchor to pull sending you 70' to the deck, but if a lead bolt rips and sends you 40' to the deck, that is not as big of a deal. They are both big deals. If the top anchors need 3.5" bolts, than so do the lead bolts. Do not skimp on the lead bolts, they are very important.
Wiled Horse · · Unknown Hometown · Joined Dec 2002 · Points: 3,669
20 kN wrote: do not skimp on the lead bolts
I agree. First bolts, crux bolts, and belay bolts should all be extra beefy.
Heck, lately I have been making them all 1/2" x 3-4" it seems. Unless its hand drilled.
Dood · · Chattanooga, TN · Joined Feb 2012 · Points: 370

I agree, why not use 3.5" when you only save a little bit of drill bit by using shorter bolts.

Jim Titt · · Germany · Joined Nov 2009 · Points: 490
ChillFancy wrote:Thanks for everyone who sent me helpful comments, and to the SCC for the information on their bolt requirements. SCC req is 3/8 stainless expansion bolts in 2.5 (for hangers) and 3.5 (for top anchors.)
The European standard doesn´t differentiate between the protection bolts and the belay/top bolts, rightly so since no-one actually knows what climbers are going to do on any particular bolt. They may climb past the top anchor and take a lead fall or they might practice multi-pitch belaying or rescues on protection bolts. I´ve seen both.
Jeff Chrisler · · Boulder, CO · Joined Jun 2009 · Points: 145

Since I started climbing outside, I've had aspirations of putting up sport routes. Although I've always wanted to do it and have definitely seen a few spots that could easily be turned into new crags, I've never felt that I had enough experience to permanently change the rock with bolts... yet. It not only takes the artistic vision to see a route on the rock, but also quite a bit of knowledge about climbing and how things feel when climbing.

I'd suggest you climb for a while longer before deciding to put up new routes and bolt them. Not to say that an advanced 5.13 climber will put up better routes than a 5.10 climber, but the experience that it took to get to 5.13 outside will certainly help. I'm not saying you have to climb 5- whatever, but if your tick list is any indication, you haven't been climbing long. Definitely get with some experienced route developers in the area and talk to them about your thoughts. I'm sure your routes would benefit from their experience and overall, the possible routes would be more respected in the area if you just went out and did it yourself.

Guideline #1: Don't be a jerk.

Sport Climbing
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