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Peter Haan
Trad climber
San Francisco, CA
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Dec 18, 2010 - 10:17pm PT
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Luke, get some of the better smaller retailers behind some orders too.
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Pennsylenvy
Gym climber
A dingy corner in your refrigerator
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Dec 18, 2010 - 10:18pm PT
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Yup,
just talking with someone about wanting one. Yes please.
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Captain...or Skully
Big Wall climber
leading the away team, but not in a red shirt!
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Dec 18, 2010 - 10:20pm PT
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Good idea, Peter. Somebody give that man some bacon, or a duct taped dead cat, at least.
Thinkin' ahead is golden. ;-)
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Tea
Trad climber
Behind the Zion Curtain
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Dec 18, 2010 - 11:01pm PT
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Love my Hurkin.
I have one's of Luke's as well, and it's damn nice too!
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deuce4
climber
Hobart, Australia
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Dec 18, 2010 - 11:54pm PT
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Greg, I used to grind down the SDS 3/8" bits so the carbide tips were sharp like a chisel bit. We used a diamond wheel on a regular grinder to do them.
I think the grinding wheel was something like the ones here (I don't recall the grit we used): http://www.mcmaster.com/#catalog/116/2627/=a7jnbj (fourth item down).
They were the tits for sandstone. I could drill a 3.5" deep hole in Zion in a few minutes. We also cut a inch or two off the SDS bit at the base.
EDIT: caveat if you do use the diamond wheel, like all grinding operations, make sure it doesn't get too hot, I always made sure I could give the tip a pinch without getting burned. Do NOT quench in water to keep it cool either--bad news for the heat treatment. Otherwise the bond between the drill and the carbide tip will be compromised. If you are only doing one drill, you have to wait quite a few minutes for every minute or so you grind. But if you are doing a batch, you do a little of each at a time (we used to sell the modified SDS drills with the Hurricane drill).
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Peter Haan
Trad climber
San Francisco, CA
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Dec 19, 2010 - 12:08am PT
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Or---continuing on Deucey's point---- you just use wet grinding processes and everything is just room temperature.
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couchmaster
climber
pdx
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Dec 19, 2010 - 12:28am PT
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Per Johns instructions, should you chose to make some up, I'd be into buying some of the bits alone Luke.
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Greg Barnes
climber
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Dec 19, 2010 - 01:03am PT
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Greg, I used to grind down the SDS 3/8" bits so the carbide tips were sharp like a chisel bit. We used a diamond wheel on a regular grinder to do them. So how does the chisel tip end up - part carbide, part normal bit metal? When the carbide tips on SDS bits disintegrate, it sure looks like the carbide part is only a small insert at the very tip - so you are grinding them down so only the outside edges of the chisel bit are carbide and the center of the chisel is the main bit metal?
I know nothing about the subject other than seeing many dozens of SDS bits disintegrate...
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Captain...or Skully
Big Wall climber
leading the away team, but not in a red shirt!
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Dec 19, 2010 - 01:05am PT
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I like HS steel, myself. I'll admit to some bias.
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deuce4
climber
Hobart, Australia
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Dec 19, 2010 - 02:11am PT
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Hi Greg-
The cutting chisel tip was all carbide. I did them two ways--so the tip was "flat", and the ones we sold had a slight point, but the sides of the carbide tip was ground to a taper.
Here's a photo of the flat version:
Here's the original photos used in the HMW brochure--maybe you can suss out something in these (not sure if they were a modified tip SDS or not).
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mucci
Trad climber
The pitch of Bagalaar above you
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Dec 19, 2010 - 02:25am PT
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I have a brand new hurricane drill, and a brand new pika.
Just sitting in the bolting box. Neither are what I want on lead when stance drilling. Both are very hard to replace bits on during a sweatfest.
The idea that on a long route, If I bugger one of those wrenches.... I am finished..
I have placed 4 bolts with a hurricane, and SDS bits. Broke 2 bits that day.
I use a 5.10 rawl drill with tons of different HSS bits, then bring along my broken Petzl rocpec that I rigged with tape (now the best drill on earth).
I think John was right upthread when he made mention of the "loose" fit petzl collet. It mimicks the way a hammer drill works.
Then again it all depends on how you drill. Hurricanes are the best option for using a short 3/8ths carbide, and or HSS bit. Pika can be modified to accept other bits as well, but the set screws are not sustainable.
Of note, John made 2 different kinds of striking points, one was rounded, and the other was flat, The Flat one is the better design (John says so himself)
Luke, much props to you on the run... I would buy one just to own a quality peice!
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bhilden
Trad climber
Mountain View, CA
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Dec 19, 2010 - 02:57am PT
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John,
I am trying to figure out what you meant by the statement that a "normal" SDS bit crushes the rock as it makes a hole while a "sharpened" SDS bit chisels the rock as it makes a hole. Can you expound on that statement?
Also, I noticed in the picture that when you "sharpened" the SDS bit you made a flat point rather than the "normal" arrow-shaped point. It is not clear to me why it isn't just OK to "sharpen" the point on the existing SDS bit without having to make it flat. What's the advantage and why don't both "chisel" out the hole.
Bruce
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deuce4
climber
Hobart, Australia
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Dec 19, 2010 - 03:18am PT
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I just liked the flat chisel tip better. Most people seemed to like an arrow point, as it is easier to keep centered. I found the flat faster, but I needed to take greater care to keep the drill angle constant as I drilled.
As far as power drills crushing, if you look at the stock SDS bit, the carbide tip is farily blunt. With 100's of hits a minute, it does better at pulverizing the rock as it drills. With hand drilling at about 50 hits a minute, the sharper point chips rather than pulverizes. If you look at the dust from a hammer drill and a hand drill, I think you will find that the hand drill dust is slightly coarser, while the hammer drill dust is pure rock dust.
just my experience, but not everyone's thinking, I'm aware. It's all theory, I actually did attempt to write a "treatise" on rock drilling way back in the 80's, it's on my bigwalls.net website somewhere.
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jack herer
climber
Veneta, Oregon
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Dec 19, 2010 - 03:19am PT
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Okay so I'll take one of these Hurricain style drills too...
But as a fan of the rocpec and its simplicity, why does'nt someone get into making HSS style bits that have the SDS style connection?
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bhilden
Trad climber
Mountain View, CA
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Dec 19, 2010 - 03:25am PT
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John,
thanks for responding. It would be interesting to do a cutaway and see exactly how each style of bit actually creates a hole. My guess is that both the more blunt and the sharpened bits "chisel" out the rock. I think the difference in the characteristics of the rock dust is probably a result of the blunter bit crushing the chips of rock that are produced from the drilling.
Bruce
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deuce4
climber
Hobart, Australia
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Dec 19, 2010 - 03:26am PT
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One idea we never fully tested was to create some sort of knurled nut at the end that one could simple hand tighten. Maybe just a simple rod that fit into it to give it the final twist, and to help untighten. We weren't really certain that we could get the required torque doing so, but after production, I think it might have been possible.
But like all ideas, the physical invention is 1% inspiration and 99% perspiration. Some prototypes would be in order.
I'll do a little sketch in a moment...
This idea would probably need some research and experimentation with various thread characteristics of the holder/nut.
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adatesman
climber
philadelphia, pa
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Dec 19, 2010 - 10:10am PT
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One idea we never fully tested was to create some sort of knurled nut at the end that one could simple hand tighten.
Hmmm... Was just pondering this last night, actually. The Double Angle collets you're using aren't exactly known for their holding power (steep ramp angles and short effective clamping area mean they really have to be tightened down to hold well), so what about simply using a keyless drill chuck? Most have relatively shallow ramp angles (more clamping force) and grip the full length of the jaw, so less torque should be needed to clamp sufficiently. Plus you can buy them off the shelf for under $50. The handle would be pretty straight forward (and cheap) too, with the option of either threaded or Jacobs taper.
That solution would likely be unnecessarily heavy though, mostly due to the chuck being able to clamp down to 1/16" or so (longer jaws and ramps). One that only spans 1/4" -> 1/2" would be ideal, but I don't know of such a creature. Building one doesn't look to bad though, judging by how this tap handle is built. It uses a similar mechanism to a cheap drill chuck, but with only two jaws...
As for the blunt carbide on SDS drills, the reason for that is carbide is actually quite brittle and a sharp edge will chip and wear down quickly and easily when hammered on; the blunter edge has more support and therefore holds up better. That said, this is from the perspective of power tools and may not apply to hand drilling due to the much lower number of blows the bit will see.
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Luke Malatesta
Big Wall climber
Moab UT
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Topic Author's Reply - Dec 19, 2010 - 11:50am PT
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Thats a pretty slick idea John and Aric, I wonder if the locking screw would mess up the threads on the holder (Johns Sketch). I have made one of these with an ER16 collet set up, ended up with a larger and heavier dill. I think that there will be a compromise between having wrenchs, or just having a larger drill.
It is hard to beat the original design.
Luke
Here is a photo of a similar design with a different collet system.
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adatesman
climber
philadelphia, pa
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Dec 19, 2010 - 03:04pm PT
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Is that a straight shank ER 16 collet chuck there, Luke? Looks like they're generally available in 5/8" and 3/4" shank diameters, so if you went with the latter you could likely see a weight savings using the former. That said, the 3/4" one I have chucked up in the lathe right now hardly weighs anything... I'll toss it on the scale in a bit (neighbor's using the lathe at the moment).
Actually, I rather like the SS ER collet chuck idea... quick and easy to make with off the shelf parts and since they are usually threaded for a stop screw it's dead easy to attach a replaceable piece to the end for hammering on.
I've got another idea or two, but holding off until I track down parts to make it work.
-a.
EDIT- Actually, before I go too far on that how much does a Hurricane weigh? Looking at the blueprint from the other thread (~4" of solid 3/4" stainless) I had assumed that the Hurricane had a bit of heft to it. Were the production drills drilled/bored out to reduce weight? Or is your prototype solid?
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deuce4
climber
Hobart, Australia
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Dec 19, 2010 - 03:33pm PT
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Luke--not a locking screw--they never work for drills--the vibration knocks them loose. The pin I sketched was just a moment arm to help turn the nut (the receiver hole would not be drilled through to the threads).
I don't reckon the keyless chuck would work: heavy, and not really designed to be impacted. In fact, I did try some back in the day--never had much luck. But one idea always leads to another, so...
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