Dave Austin
starting to spend too much on rocks
Member since January 2008
Posts: 104
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Post by Dave Austin on May 28, 2011 2:54:55 GMT -5
Hi,
looking for ideas on tightening the nuts on each end of a shaft, I now this sounds like a daft question, but I have shaft that doesn't have opposite direction threads on each end, so if you put a spanner on each end and then rotate in opposite directions so that the nuts both tighten, with this shft I have rotate the spanners in the same direction, for example, with the shaft in front of me I have to draw the spanners towards me to tghten the nuts, but I have to figure out how to hold the shaft from rotating so that I can nip the nuts up.
I thought about mole grips near the pully onto the shaft but was wondering what other ingenious solutions there might be out there.
Cheers
Dave
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Post by johnjsgems on May 28, 2011 8:25:51 GMT -5
If not too tight you can hold the belt. If tight you can hold the pulley or the shaft somewhere where pipe wrench gouges won't matter.
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Dave Austin
starting to spend too much on rocks
Member since January 2008
Posts: 104
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Post by Dave Austin on May 28, 2011 9:23:21 GMT -5
Cool, thanks for that, will start building soon cheers Dave
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Post by parfive on May 28, 2011 12:42:00 GMT -5
Sounds like you’re building a cabbing machine, Dave. If you’ve got several wheels and spacers on each end of the shaft, there shouldn’t be a need for spanner-tight – hand-tight should compress everything enough to hold just fine. Never had a problem with hand-tight.
There’s also nothing wrong with having a right-hand thread on both ends of the shaft. Everyone makes a big deal about having a left-hand thread on one end, but it just ain’t necessary. And as you just learned, it’s also a little more awkward.
Another option for holding a shaft steady while spannering ;D – cut a screwdriver slot in the end of the shaft with a hacksaw or file or a Dremel.
[Text modified for the faint-hearted and those who don’t run with scissors.]
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Post by jakesrocks on May 28, 2011 14:10:04 GMT -5
Parfive, you've obviously never had a wheel come loose on the left side of an arbor with right hand threads on both ends. Unless you're using a soft start, (capacitor start) motor, centrifugal force will try to unscrew the nut on the left end of the shaft. No fun having a wheel chase you around the shop. Not to speak of the damage done to an expensive wheel. Best fix for this type of arbor would be a castellated nut, and a hole drilled through the shaft for a cotter pin. Bend the cotter pin down tight to the nut, so it doesn't catch your hand. Don
Oh, and parfive, just in case you have one of your brilliant, smart ass answers to this, Yes, I am speaking from experience. Fortunately it wasn't my machine, and I jumped clear just as the wheel started to wobble on the shaft. My friend who built the machine lost an expensive wheel, and learned a valuable lesson about home built equipment.
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Post by parfive on May 28, 2011 17:23:28 GMT -5
Five years so far with that pair of rh threads, Jake. Hand-tight. Never a problem. YMobviouslyV.
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Post by jakesrocks on May 28, 2011 18:14:47 GMT -5
Good luck. If those are right hand threads on the left end, they're an accident waiting to happen, unless you used a self locking nut, epoxy on the threads or the castellated nut and cotter pin. Oh, you could probably get away with a jamb nut too. But I won't try to teach the all knowing parfive anything. After all, he's a genius, and has all the answers.
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quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
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Post by quartz on May 28, 2011 22:53:36 GMT -5
I don't recognize the term "molegrips", but think our visegrips may be equivalent. With a piece of aluminum sheet about 1/16" or more thick under each jaw, a shaft can be grabbed very tightly without damaging it.
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Post by Rockoonz on May 29, 2011 0:35:25 GMT -5
On arbors with difficult nuts I like to position a wrench so the handle sticks out the front, hold the pulley by squeezing the belt together with my fingers away from the nip, then take a generous whack at the end of the wrench with a dead blow hammer or rubber hammer. Usually you can "shock" the nut loose this way. If that doesn't work the aluminum soft jaws on a vice grip would be my next step. When you re=assemble finger tight is NOT enough! You don't need more than nice and snug with a wrench either, over tightening can cause problems too. My technical term for arbors with right hand threads on the left side is "scrap metal". If you don't have the facilities to build it right let someone else build it and spend the time you would have spent "saving money" working a little overtime to pay for it.
Lee
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Dave Austin
starting to spend too much on rocks
Member since January 2008
Posts: 104
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Post by Dave Austin on May 29, 2011 3:39:10 GMT -5
Hi Guys,
first of all thanks for all the input, it's very much appreciated and I am sure I do have left hand on one end and right hand thread on the other, in fact I just went and checked it, first I stood at the one end of the shaft and tightened the nut, it rotated right, then went to the other end and did the same and it rotated left. My question was purely how to hold the shaft and prvent ot from rotating while I tightened those nuts up and between you you have provided some good ideas.
It's at time like this I wished I lived in the US as I have had to import stuff into the UK, like the 4 8X3 expanding drums and shipping and customs charges are a killer. Plus it seems that Lapidary is whole lot more popular over there and supplies of harware and rock are much more plentiful. For example you watch anything on Ebay over here, say a two wheel cab machine that's really only any good for scrap and it goes for a ridiculous amount of money, that's why I prefer to build my own kit.
Having said that, shaft (arbors) go for reasonable amounts as I have just picked up some nice Picador parts so there are potentially 4 machines waiting to be built now, I wonder if there would be a market over here for the machines I build, reckon I could build a 4 wheel expanding drum machine for about 500 GPB including motor, that's about US$825, looking at market rates over in the US and taking into account shipping to to the UK and customs charges that would seem quite good for the home market, food for thought.
I will star a new thread for the build of the first machine to come off the line - a 4 wheel cabber with 4 - 8X3 expanding drums using Rez belts impregnated with diamond, should make the Lapis gleam :-)
Thanks again guys
Cheers
Dave
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quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
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Post by quartz on May 29, 2011 8:55:24 GMT -5
After re-reading your initial post this A.M. I see you said that from the machine front you draw both nuts toward you to tighten them. This means you have a right hand thd. on the left side and a left hand thd. on the right side. Fix the rotation problem by turning the shaft around. Granted, you still have to hold the shaft to tighten the nuts, but you won't be taking such a chance of throwing parts at yourself.
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adrian65
Cave Dweller
Arch to golden memories and to great friends.
Member since February 2007
Posts: 10,777
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Post by adrian65 on May 29, 2011 11:19:17 GMT -5
Why don't you make a cut anywhere along the shaft (flattening the surface on two opposite sides), such as you could insert a counter-wrench in that cut while you tighten or loosen any of the nuts ? Adrian PS. Like here:
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unclestu
Cave Dweller
WINNER OF THE FIRST RTH KILLER CAB CONTEST UNCLESTU'S AGUA NUEVA AGATE
Member since April 2011
Posts: 2,298
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Post by unclestu on May 29, 2011 13:12:09 GMT -5
I have had my nuts busted and even twisted but I never had them tightened. I guess having them tightened is a good thing if nuts are like lips because we all know that loose lips sink ships. ;D Stu
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Dave Austin
starting to spend too much on rocks
Member since January 2008
Posts: 104
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Post by Dave Austin on May 29, 2011 16:03:06 GMT -5
After re-reading your initial post this A.M. I see you said that from the machine front you draw both nuts toward you to tighten them. This means you have a right hand thd. on the left side and a left hand thd. on the right side. Fix the rotation problem by turning the shaft around. Granted, you still have to hold the shaft to tighten the nuts, but you won't be taking such a chance of throwing parts at yourself. Hey Quartz, very sound advice and much appreciated thanks Dave
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