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Juan Maderita
Trad climber
San Diego, CA
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May 12, 2010 - 05:20am PT
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Okay, I said that I would report the results after testing the slide hammer method of removal. Sacrificed a few of my 5/16" Rawl Drive "buttonheads" for the testing in Baja granite.
The slide hammer worked almost as expected. It did the job, though with some effort. It would be laborious to carry it to the top of a route and rappel with it, particularly after adding a second 2.5 lb. plate for the approx. 6 lb. hammer. It is rather awkward to use, even while standing on flat ground.
Hammering the "tuning fork" under the bolt hanger was the most difficult part. (The tuning fork end of the slide hammer is the cut-off end of a Vaughan "SuperBar").
Placing the fork below the bolt, with the two prongs pointing upward allowed the fork to fall out, due to gravity, after each hit of the slide hammer. That situation was solved by placing the fork with prongs pointing down, and placing slight leverage on the pipe to maintain some tension.
Placing my hand with thumb pointed toward the bolt was much more comfortable for hammering, as the meaty part of the hand absorbs the shock. The bolt was fully extracted with 8 to 10 hammer blows.
As an experiment, this was an interesting project. As for the tool, I'd give it a grade of D+.
Yes, a slide hammer will remove a 5/16" buttonhead, however, it is a heavy and redundant piece of specialized equipment in the arsenal.
A combination of large "tuning forks" will perform more efficiently than a slide hammer.
Driving the bigger tuning forks under a 5/16" bolt takes some serious hammering. Rather than using a climbing hammer, a 2 or 3 lb. sledge (aka: engineer's hammer) will make the job much easier.
The cut-off end of a Vaughan SuperBar seems to be a good tool for the initial 1/4" of extraction. It is slotted to 5/16". The slot is flared wider at the tip to ensure wrapping around the bolt. If misaligned slightly, it will guide into proper position. Using a grinder, the angle of the chisel end is made more acute and thinner. That makes it easier to drive under the bolt hanger, with less force to do the job. The outer corners of the chisel tip are angled and rounded to minimize sharp edges gouging the rock.
The modified 1" cold chisel can be used as the first and only tuning fork, or as a second tool, after the intial loosening with the SuperBar.
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Juan Maderita
Trad climber
San Diego, CA
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May 12, 2010 - 06:04am PT
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Part two of my testing was to address my questions about the feasibility of using a puller to remove 5/16" Rawl Drives.
My questions were: "Can a 5/16" Rawl Drive be removed by pulling on the hanger?" and "Will the sheetmetal hanger fail or shear around the head of the bolt before the bolt pulls out?"
I wanted some answers before attempting to design a puller.
Far from a laboratory experiment, I had some crude tools for the job: a Warn 12,000 lb. winch.
Placed a new 1/4" Rawl Drive on a rusty, used Leeper hanger.
A flick of the toggle switch and it popped right out, without tearing the sheetmetal hanger. I used the Leeper because it appears to be the thinnest/weakest of hangers.
The 5/16" Rawl Drive and a thicker "Lucky" brand plated steel hanger came out as a unit. The hanger shows some stretching around the bolt hole. (I'm happy to note that the 7,000 lb. van slid forward a few inches before the bolt pulled out, inspiring some confidence in those 5/16" bolts).
My questions were only partially answered. I lacked an old Leeper or SMC hanger (the old thin plated type) with a 3/8" hole for testing on a 5/16" bolt. It appears that a puller will work for a 5/16" Rawl Drive on a modern hanger. A puller might work on a 5/16" Rawl Drive with a weaker/old style hanger.
That is enough info to proceed with building and testing a puller. If successful, a puller should offer the advantages of easy hammerless operation with little exertion. If designed correctly, it should not gouge the rock.
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cragnshag
Social climber
san joser
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May 12, 2010 - 03:18pm PT
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Minerals, thanks for all the info in your post. I had my own small cringe, though, at the following words:
That’s what I have been installing on my new routes in Tuolumne over the last few years – 3/8” x 1 7/8” 4-piece or x 2 1/4” 5-piece carbon steel bolts with stainless Metolius hangers, as well as a few stainless Petzl hangers. I’d use stainless 5-piece bolts if the cost wasn’t so outrageous...
I realize that they are very expensive, but using your logic from the same post (not replacing 1/4" with 5/16" because the 5/16" will have to be replaced later)- why create more work for later? At a savings of a couple bucks per bolt, some ASCA or other volunteer will, sometime in the future, spend a whole day accessing and replacing, say a 10 bolt route. That same person's time is worth at least $10 bucks/ hour so the opportunity cost of around $100 bucks is lost to that route. Why not just do it proud in the first place. Isn't Tuolumne worth it? :)
I work in the precast industry and use all kinds of anchors for every job we do- thus have some good deals going with the major hardware manufacturers because of the volume we buy. Email me and I'll see what price I can get you for the SS Powers bolts. Maybe split the cost with your partners in crime or just make them pay everything in exchange for you leading the scary sections.
Bob
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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May 12, 2010 - 03:41pm PT
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Thanks Bryan and Greg. 3/8" it shall be.
Greg, I think I'm more or less fully stocked. When I arrive, I'll go through my inventory, and bug you if I need anything else.
The plan is Pacemaker.
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Minerals
Social climber
The Deli
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May 22, 2010 - 01:36pm PT
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Mucci, the 3/8” buttonheads on SQ are the Spike buttonheads that I mentioned earlier and posted a link to. That’s one of Nanuke’s trademarks…
The two washers on the 1/4” buttonhead act as a retainer for the keyhole hanger or wire rivet hanger while the rivet is clipped. When it is time to pull and replace the quarter-incher, the tuning fork can be placed between the two washers. The bottom washer acts as a spacer and helps to protect the rock from the tuning fork and the top washer prevents the head of the bolt from stripping, while driving the tuning fork.
“(I'm happy to note that the 7,000 lb. van slid forward a few inches before the bolt pulled out, inspiring some confidence in those 5/16" bolts).”
WOW!!! Good stuff, Juan! Thanks for posting. Those plated Lucky hangers are definitely heavier and more beefy than the stainless SMC hangers. I’ve been using some with 1/4”ers but the weight adds up with a bunch of ‘em.
Chief, I suppose I’m spoiled by bulletproof Cathedral Peak granodiorite, where it’s tough to mess up a hole while pulling a bolt. You are using power (legally) to replace bolts, right? Why not try to drill the cone out with power, rather than try to funk it out and have the rock blow out? Is this a possibility?
Thanks for the invite; I should be down your way later this month, and hope to hit up Clark for at least a day or two. Do the Benton Crags need any replacement work?
Cragnshag, yeah, in some ways, you’ve got me there.
From this thread:
http://www.supertopo.com/climbing/thread.php?topic_id=1047623&msg=1047965#msg1047965
“I use 316 SS wedgies almost exclusively. Sure you can't replace them in the same hole, but the 316 is so damn resistant to corrosion (in non-chloride enviroments like the Sierras) that I'm pretty sure that they will outlast mankind's brief appearance on this planet.
Thing is, I do all my drilling ground up by hand- so it is tough to stand there another 5 minutes to make a hole deep enough for a 5-piece (OK sometimes I have a really good stance and I'm just being lazy!). Now if someone manufactured a 5-piece that was 1.75" long AND 316 SS, then I might switch.
At this moment, the wedgies work the best for me. My compromise is in using 316 SS over 304/ 18-8 SS such that future replacement may be a moot point anyway. I pay almost twice as much for the 316 ($1.85 vs $1.00) for 3/8" dia shorties. Still a good price though since I bulk order them through the company I work for (precast concrete). And I get an ICBO report rated anchor to boot.”
So maybe it was my comment about wedge bolts above? I still disagree with you on wedge bolts vs. 5-piece bolts. I would much rather place a carbon steel 4-piece bolt that eventually needs to be replaced with stainless, than use a stainless wedge bolt in the first place that can never be pulled. This is part of the reason why The Chief has to drill new holes on the Eastside rock – wedge bolts.
And basically what you say above is just what Pete said earlier… you don’t want to spend the extra time drilling from a stance to get that 2 1/4” bolt in, and thus use shorty wedge bolts? And to follow this same logic, why are you settling for non-removable stainless wedge bolts when, for just “a couple bucks per bolt” you could be placing a stainless 5-piece that can be removed?
I have lots of time to place and replace bolts so it doesn’t bother me at all to have to return to my routes for more maintenance. In fact, I enjoy it. If I didn’t care about the state of the bolts on my routes, I would just leave all of the 1/4”ers that I originally place and say… “Here ya go! Have fun!” But I take the time to go back and replace those 1/4”ers until they are all gone.
Yes, I should use stainless in the first place.
According to Nate D’s link in this thread…
http://www.supertopo.com/climbing/thread.php?topic_id=965840&msg=966748#msg966748
…the carbon steel 3/8” x 1 7/8” bolts go for $0.82 each while the stainless 2 1/4” versions go for $4.60 each. That difference is more than “a couple bucks per bolt.”
Splitting the cost with my partners in crime? That wouldn’t work, as I have been the one supplying the bolts that THEY place… for free…
I guess we will both continue to cringe.
Thanks, Pete. Are you going to replace the rivets with 1/4” buttonheads?
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Clint Cummins
Trad climber
SF Bay area, CA
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May 22, 2010 - 03:25pm PT
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Roger Brown replaced the 5/16" bolts on Rum, Sodomy and The Lash on May 14.
His approach on a route with 5/16" bolts is to pull one of them, and see how strong it is. If the bolt is hard to pull, he just replaces the one bolt he pulled. If the bolt is easy to pull, he replaces all of them.
The rock on Rum, Sodomy and The Lash is somewhat grainy, and the first bolt pulled fairly easily, so he replaced all of them. Roger also pulled and replaced the anchor bolts. The highest protection bolt was 1/4", so Roger was not sure if it was original. We checked with Norman Boles, and he said it was original (due to a broken 5/16" bit), so Roger will replace that bolt also.
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Clint Cummins
Trad climber
SF Bay area, CA
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May 22, 2010 - 03:32pm PT
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I do new routes with Bob, and I'm fine with the 316 SS wedge bolts. I use the 304 SS wedge bolts for my own stuff, they cost about $1 each when bought with a good deal. Considering how good many of the 1/4" are after 34 years, I think the 316 SS 3/8" will be good for 200+ years. Fine for the obscure routes we are doing, I think.
If it was for a well-used hauling anchor on El Capitan, then the bolts may get worn/deformed and may need to be replaced on a regular basis. Although that is a slightly different application, where stiffer non-SS bolts hold up better.
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Minerals
Social climber
The Deli
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May 22, 2010 - 03:49pm PT
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200+ years? Seriously, Clint? I am thinking more like 50 to 100 years. But even so, regardless of whatever number sounds right, a new hole will still need to be drilled. Where does it end?
I am probably just wasting my time here…
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Clint Cummins
Trad climber
SF Bay area, CA
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May 22, 2010 - 03:59pm PT
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200+ for the 316. But it's a fairly wild guess.
It would be nice to make a real calculation on the failure time.
Still, Bob pays extra for the 316 instead of the 304. Also 316 chain and quicklinks.
More practically, I think probably nobody will ever repeat the new routes we are doing. They have long approaches, and there are 2000+ routes that are closer and better.
Although if we were committed to this concept, we would use removable bolts like the Fixe Triplex and leave the routes with no bolts at all.
So probably the real thought is that a few of our friends might do the routes in the next 10 years, and other people might look to see where our bolts are, so they can do other new routes of their own nearby.
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cragnshag
Social climber
san joser
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May 22, 2010 - 04:55pm PT
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I should be climbing today... but instead I'm in front of my computer!
Minerals- Believe it or not I do have longevity in mind. 316 SS is a highly stable and inert material. In otherwords it's not-biodegradable in the common sense. Water, O2, and time are not enough to cause section loss in stainless bolts. You'll need some chloride if you want anything to happen- and salt is in short supply in the Sierra. I'm guessing the biggest threat to the bolts will be exfoliation of the rock itself.
So I don't foresee anyone needing to drill a new hole to replace any of my 316 SS wedgies. Not in 200 years, not in 500 years. Just clip the thing and keep climbing. Of course this assumes that people in the future want to hike a long way to climb an obscure route!
All this talk of removing old bolts has got me thinking about ways to test in-situ carbon wedgies. My buddy Banquo has a hydraulic ram and load cell in his garage. If we convert the load cell to run on 6 volts DC, then the whole system is portable. Basically you screw the jig onto the stud and then pump the ram (that does't quite sound right, does it?). You can pull directly outward on the bolt to say 2500 lbs tension- about half the inelastic yeild strength. If the bolt holds, then it's good. Put the hanger back on and keep climbing. If it pulls, and the source of failure was loss of section of the cone sleeve, then you have a clean hole to put in another bolt.
I wouldn't want to test it much more than 2500 lbs due to the strain hardening that would occur at the point of inelastic yielding. The strain hardened area would be more brittle and more susceptable to corrsion than the surrounding metal.
This same set up could be used to test my own SS wedgies in 200 years.
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Jay Wood
Trad climber
Fairfax, CA
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May 22, 2010 - 04:58pm PT
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Early in this thread, the idea of using a claw hammer as tuning fork was proposed.
Striking two hammers head-to-head is a bad idea (hardened steel chips flying).
Maybe not as bad if one is a less hardened piton hammer, but still.....
I'd be extra careful striking roto hammer tool steel also.
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CascadeOtto
Trad climber
Seattle, WA
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May 24, 2010 - 06:57pm PT
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Ksolem - I like the looks of your prybar tool. What brand is it? Did it come with the handle/hand protector?
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Greg Barnes
climber
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May 24, 2010 - 07:58pm PT
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As far as the longevity of stainless stud/wedge bolts - I always assumed that over long time periods in fairly dry climates they would be done in by mechanical failure instead of corrosion. Does anyone know more about work fatigue - referenced in Duane Raleigh's old Climbing article on mechanical bolts:
Because their exterior threads make them prone to work fatigue, wedge bolts aren't nearly as dependable as solidhead sleeve bolts. For that reason if you must use wedge bolts consider 1/2inch diameter ones, which still fit through a 1/2 inch Petzl Coeur bolt hanger, and are far more resilient than the 3/8inch size.
[side note - the Petzl Coeur hanger is made in 12mm which just barely fits the head of a 1/2" stud/wedge bolt since the threaded heads are actually slightly less than stated diameter - if you want true 1/2" holes, Fixe now makes 13mm hole hangers]
I don't know much about the long term stresses on a wedge bolt sitting in the rock forever, but I would assume freeze/thaw cycles and heating/cooling of the bolt vs rock would apply some sort of varying forces against the bolt.
Anyone?
Also for the serious chemisty/metallurgy geeks - anyone know what the common pollution byproducts ("acid rain" etc) are in the Sierra, and if they have effects on 304 or 316ss? Lichen and soil byproducts? I would assume that basically no one has thought about these kind of issues over extreme time periods (100 years plus)...
edit: oh yeah, here's the Raleigh article:
http://www.safeclimbing.org/education/mechbolts.htm
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Tork
climber
Yosemite
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May 26, 2010 - 03:50pm PT
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3 for 3 baby! Also pulled this 3/8ths Star Drive
Used a 1/4" fork and a couple of LAs
Splits the sh#t out of the fork but I just beat it back, file the tips.... as good as new.
I bought about a dozen 5/16" from Fixe for new routes but I am 0 for 3 placing those peices of sh#t, bend every time.
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Juan Maderita
Trad climber
San Diego, CA
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Jun 25, 2010 - 10:18pm PT
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My first prototype of a new puller was a partial success. That's a spin on saying it failed to pull a newly placed 5/16" bottonhead. It easily pulled a 1/4" buttonhead, and met the goals for ease of operation. The device proved to be self-centering and stable. Once hooked up to the hanger, it could be operated with one hand.
The failure occurred while attempting to extract a freshly placed 5/16" buttonhead. Wow, those bolts continue to amaze me with their pullout strength! I had to lean into it with both arms to turn the 12" hand crank. Still, it wasn't budging. Then the 1/2" (x 13 coarse thread) Grade 2 tap bolt snapped off. The experiment came to a "grinding" halt.
I'm having difficulty locating a long 1/2" Grade 5 or Grade 8 tap (fully threaded) bolt. As soon as I can get my hands on one, I will weld it to the handle and try again. A Grade 8 bolt should have more than double the strength of a Grade 2.
If a hardened bolt fails, then a 5/8" or 3/4" bolt and coupling nut will be needed. That will increase the size and weight of the device. I'm fairly convinced that the idea is sound. I'm not an engineer, so it will take a few iterations to get it right, shaving weight and bulk, and simplifying the design so that it can be easily duplicated by others.
The complicated stabilizing legs will likely be replaced with something welded directly to the main square-tube body.
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cragnshag
Social climber
san joser
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Jun 26, 2010 - 02:45am PT
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Hey JM,
McMaster-Carr has anything and everything: www.mcmaster.com
Plenty of grade 8 tap bolts in longer lengths, no problem. 1/2", 5/8" 3/4", etc.
My 2 cents:
Since you broke a 1/2" dia bolt, it's probably best to go with 3/4" dia regardless of grade. You'll want the bolt to work after many cycles- a 1/2" dia grade 8 may work for a while, but will suffer from fatigue and strain hardening due to service loading closer to yield strength. With a 3/4" dia grade 8 you should be worry free (of course you'll have to make a new jig to fit the larger bolt). Good news is if you get the 3/4" x 16 threads per inch you'll get more effective leverage per crank arm rotation (20% more) than the 1/2" dia x 13 tpi. And the larger circumference of the threads on the 3/4" bolt (and the longer associated coupling nut) means less localized stress on the threads themselves- prolonging life of the bolt and nut.
part # 92620A881 3/4" x 6" tap bolt grade 8 (16 tpi) $9 ($8 for the 5")
part # 90977A220 3/4" coupling nut 2 1/4" long grade 5 (16 tpi) $7
I buy several hundred of these per year (the 10 tpi version) for use in GFRC connection hardware (I get them for about $2 apiece from a bulk supplier!)
or if you want to go 5/8":
part # 92620A315 5/8" x 5" tap bolt grade 8 (18 tpi) $11
part # 90977A210 5/8" coupling nut 2 1/8" long grade 5 (18 tpi) $5
Be carefull welding the coupling nuts- I've seen slight heat warpage welding 2" long 3/16" fillets on 3/4" couplers. The result was the bolt was a bitch to turn in the nut- and the last thing you want is any extra friction in the system. You may even want to order a couple extra couplers in case this happens. In a typical connection hardware production run, welded 3/4" couplers (to A36 mild steel) we usually get 60% tight turning (ie need a wrench to turn) 35% EZ turning, and 5% almost stuck (need to tap the threads). I'm not sure what the weld shop does to prevent warpage- I think they try to keep the heat to a minimum?
Happy bolt yanking. That's a great gizmo you've got there! Send some pics of the next bolt pull.
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Juan Maderita
Trad climber
San Diego, CA
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Jun 26, 2010 - 03:51am PT
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Hey Cragnshag,
Thanks for doing my homework! A frustrating 1/2 hour of searching turned up nothing.
And thanks for the great advice. No doubt you're right about upgrading to 5/8" or 3/4". Will have to take some measurements to be certain, but I think I can cut the top off, insert a 5/8" coupling nut, and weld the top back on easy enough. There may not be enough clearance for a 3/4" coupling nut, in which case the next larger square-tube size will be required.
I thought about the use of fine threads for the reason you described. Coarse threaded coupling nuts and Grade 2 tap bolts were readily available, so I went with that. With your parts source, a switch to fine thread will be made.
You're right about the warpage on the coupling nut. I must have been in the "5% almost stuck" category despite alternating MIG tack welds on each side. Chasing the threads with a tap solved the problem. Perhaps TIG would control heat better.
Supertopo never ceases to amaze me. There is always an expert here on the most obscure of topics. I never expected someone with expertise at welding coupling nuts!
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Clint Cummins
Trad climber
SF Bay area, CA
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Jun 26, 2010 - 04:40am PT
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Good stuff, Juan and Bob!
Pretty nice looking puller, Juan.
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cragnshag
Social climber
san joser
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Jun 26, 2010 - 11:49am PT
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Man, you guys stay up late!
Hey Juan- I just remembered a trick the guys use when welding the couplers-before welding, spin the coupler onto to the middle of a long tap bolt. The bolt acts as a heat sink, giving the heat a place to go.
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WBraun
climber
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Jun 26, 2010 - 11:50am PT
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Juan Maderita
LOL what an awesome arsenal of tools you've got there.
Some nice improvisions too.
You always the man .....
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