1/4" SS Spike tests

Discussion Topic

Return to Forum List

This thread has been locked

Messages 1 - 11 of total 11 in this topic

Banquo

climber

Amerricka

Topic Author's Original Post - Mar 13, 2013 - 10:04pm PT

I tested four 0.25" x 1.5" stainless steel spikes. I got these from Minerals but am not sure of the original source. I pulled two out in tension getting 1190 lbs and 1210 lbs. I tested two in shear getting 3150 lbs and 3080 lbs. These are maximum load achieved. The shear tests had deformed a great deal before reaching the maximum load.

For comparison, 0.25" x 1.5" carbon split shanks 1860 lb tension and 3340 lbs shear with similar shear failure.

Someday when I have nothing else to do I'd like to test some of the shorter ones. Be nice if somebody else drilled the holes too.

[Click to View YouTube Video]

Strider

Trad climber

ಠ_ಠ

Mar 13, 2013 - 10:42pm PT

Love the tests, thanks for doing the work!

If you ever need some 3/8" x 2.25" SS studs or 1/4" x 1.5" Split shank buttonheads to destroy, let me know. I have got a few lying around and wouldn't mind seeing them put to good use.

-n

Clint Cummins

Trad climber

SF Bay area, CA

Mar 13, 2013 - 11:55pm PT

Nice work.
The 1/4" x 1.5" SS Spike looks pretty competitive in shear (I am thinking anything over 2400 is as strong as it needs to be).

I agree, results for the shorter ones would be good, too.

Bruce has a Bosch - we could probably drop by after a Pinnacles trip and drill some holes for you!
Would the hole shape be comparable to hand drilling?
I've heard a power drilled hole can be smaller diameter than a hand drilled hole with the same SDS bit?

Greg Barnes

climber

Mar 14, 2013 - 12:07am PT

Minerals tested those spikes in rock and reported that they were total junk and came out like butter. It'd be good to hear details from him.

Clint Cummins

Trad climber

SF Bay area, CA

Mar 14, 2013 - 12:14am PT

I wonder if the ones Minerals tested:

were the shorter ones

were in a softer mix of granite

The shear results will depend on how well the edge of the hole holds up under pressure. Once it starts to round over, the loading looks more like tension.

Dan, what is the PSI of the granite block you are using?
And do you know the range of PSIs for some different granites?

Greg Barnes

climber

Mar 14, 2013 - 12:23am PT

Minerals always uses 1.5" buttonheads so I'd bet he was testing the same length stainless spikes. Don't know where he was checking them out. I think he gave me a few of the stainless spikes, let me go see if I can find them....nope, can't find any.

Banquo

climber

Amerricka

Topic Author's Reply - Mar 14, 2013 - 12:55am PT

Since I got these spikes from Minerals, I suspect they are what he has but he hasn't told me about any tests he has done. I will say the rock I am using is pretty much as good as granite gets. Non-granite, weathered granite, weathered hardware, etc would probably produce lower results. I would consider my conditions close to ideal.

Minerals is negative about the 8mm split shanks which is an opinion I agree with. Perhaps he will chime in and state his opinions himself.

I don't know if power drills produce larger or smaller holes, or straighter, smoother, etc. I pretty much don't care. I drilled a climbing bolt hole with a Makita once and have felt like a rapist ever since. Just me and my personal position on the drilling topic. I do have a roto-hammer and I suppose I could use it if I wanted to.

Perhaps we should have a play date and spend some time testing anchors. Most of my gear is fairly portable. We could even do a testing campout someday. If I bring my gear, somebody else has to bring the beer. Pull-out tests are easy to do in the field, shear tests can be difficult.