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i have no idea if this would work,
but perhaps some bolt companies would donate bolts to be tested as muir valley is a totally non-profit endevor, they could get tax write-offs and after testing to decide the best bolt/hanger configuration the company would then have the advertising and pr benifit proving itself better than the compitition. that's all just hypothetical, i have absolutly no idea if it would work.

all that aside, thanks again for all your work, i can count on one hand the amount of times i've climbed outside of the valley this year on one hand and have 3 fingures left and a thumb left over. and the only thing i've ever noticed about the bolts is that i don't notice them much at all. thanks

weber wrote:
Of course, if you torque too high -- say above 45 foot-pounds, then you greatly increase the chance of cracking the rock. Go higher than about 65 foot-pounds and you increase the chances of twisting the bolt head off.

No easy answers.

Rick

This is true. I know of several instances in which I cranked the bolts down too tightly and the rock cracked making it necessary to remove the bolt and drill a new hole. I measured my torque and it was greater than 60 foot-pounds. Sometimes the bolts tighten quickly and other times it may require several turns of the wrench. Ultimately it all comes down to the rock quality. In my opinion these bolts are all good and the rock is usually the weakest link.

Feanor007 wrote:i have no idea if this would work,
but perhaps some bolt companies would donate bolts to be tested as muir valley is a totally non-profit endevor, they could get tax write-offs and after testing to decide the best bolt/hanger configuration the company would then have the advertising and pr benifit proving itself better than the compitition. that's all just hypothetical, i have absolutly no idea if it would work.

all that aside, thanks again for all your work, i can count on one hand the amount of times i've climbed outside of the valley this year on one hand and have 3 fingures left and a thumb left over. and the only thing i've ever noticed about the bolts is that i don't notice them much at all. thanks

Good suggestion. In fact Kevin Daniels of FIXE has sent us some hardware for testing.

Rick

J-Rock wrote: In my opinion these bolts are all good and the rock is usually the weakest link.

Amen!

What about long term? Will the glue weaken over a period of time of given weather? I know that using glue in anchors in buldings and such is great stuff, but for the most part, they are not exposed to the weather elements. Have the manuf. looked into this by chance? (Just my 2 cents)

Don't understand most of this discussion, but I do understand that Rick is spending plenty of time and money to make sure that we all have the best day of climbing we can!

Thanks Rick!

I started climbing in S. Wales about 15 years ago. One of the local activists, a prolific new router of the day, started using homemade marine-grade stainless steel staples. S. Wales has both sandstone and limestone climbing crags.

I recall him using 1/4" marine-grade stainless rod cut to length and cold formed it into a U. He then drilled two holes (roughly 2" apart) one vertically above the other and glued the staple in place with a 2-part exopy.

As I haven't climbed at home for the past 8 years, I wrote to a couple of friends in S. Wales and asked the following questions.

Are homemade stainless staples still being installed on new routes?
If not, why did they fall out of fashion? Are staples now considered a bad idea? If so, why?

If staples are still in common use,
- What rod diameter is used?
- What grade of stainless steel is used?
- What diameter drill bit is used?
- What leg length/insertion depth do you recommend?
- How far apart are the two drilled holes?
- What type of adhesive is used?
- How many staples have you placed?
- How old is the oldest staple still in use?
- Have any staples broken/failed catastropically?
- Have any staples become loose or pulled?

I'm not recommending staples as the solution, but it was a solution used S. Wales in the early-90s. If nothing else we will hopefully we'll get an idea of the longevity of glue-ins.

There were several reason why stainless staples were used in S. Wales some of which are and are not applicable to the Red.
- salt-water spray and seepage corrosion resistance; climbing equipment was not available in marine-grade stainless.
- rough rock; staples do not require a flat area of rock.
- low cost; stock stainless rod has little commerical value-add
- no sharp edge; people typically rapped directly off them.

I'm sure there are many more pro and cons than I have listed below,

Pros:
- inreased surface area for the adhesive
- redundancy of two seperate adhesive bonds.

Cons:
- two holes too close together may weaken the structural integrity of the rock.
- smaller diameter "appears" less substantial than a single 3/8" bolt.

Hopefully, I'll be able to get you some good data points and then put you in contact with a group that choose the glue-ins 10-15years ago. By now they may have come full circle and using rawl bolts, who knows?

PLJ

weber, If you wanted to use a standard hanger with a glued in threaded rod and nut, couldn't you use a nylock or a pinched crown(not sure of the technical name of these, look similar to a regular nut, but with a slight deformation punched into the top. they're used regularly on automotive applications on things like steering and suspension that you don't want working loose) nut. they require a wrench to turn even when not loaded, because of this they'd probably be unsuitable for a sleeve bolt(tensioning problems), but should fit the bill for a glue-in.
You could also just peen the threads on the threaded rod once a regular nut was in place. Again, this would make it possible to remove the nut if necessary, but impossible for the nut to unscrew on it's own.(i've used this technique on studs and bolts in automotive applications subjected to heavy vibration for years with no problems)

Rick - I have access to compression testing equipment at work. If you could get me some plugs of rock I can test them. I'd need a relatively small piece -- we commonly use .300" Dia x .500" Thick. Bigger is fine too but the equipment can only push 5 tons (that's 141000 psi). The more uniform the better as changes in the diameter or unparallel faces introduce error into the result.

dhoyne wrote:Rick - I have access to compression testing equipment at work. If you could get me some plugs of rock I can test them. I'd need a relatively small piece -- we commonly use .300" Dia x .500" Thick. Bigger is fine too but the equipment can only push 5 tons (that's 141000 psi). The more uniform the better as changes in the diameter or unparallel faces introduce error into the result.

Cool! Thanks!

I think I can machine some slugs of Corbin sandstone for you to test at these dimensions. I'm guessing this stuff ranges from about 700 to 2000 psi compresive strength. I would like to know the strength of the rock we tested the FIXE glue-ins in.

Experienced route developers can kind of tell the hardness of the rock by how it drills. If the stuff comes out dust, the rock is usually pretty hard. If it drills easily and the stuff comes out like granular sugar, then it's better to pass up this location and look for a better piece of rock. Again, this is only a general rule.

Rick