I am putting together a spindle for a metal spinning lathe I am making from scratch.
The right end has a 1x8 thread and is fine. The left end of the spindle requires a nut to hold the whole thing tight. Will a 3/4X16 right hand thread losen or do I have to go to left hand thread. I bought a couple of left hand nuts but the 2" dia die cost $31.53 + freight from MSC...anybody have any thoughts? Thanks
Left hand or right hand thread?
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dsergison
Re: Left hand or right hand thread?
if you use locktite, double nuts, or castle nuts, or safery wire, or nylock nuts, etc.... it should hold fine.
also, you should do one of those even if using left hand nuts, because the possibility of it cranking it's self down to failure is just as bad or worse than just comming loose.
also, you should do one of those even if using left hand nuts, because the possibility of it cranking it's self down to failure is just as bad or worse than just comming loose.
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gmacoffline
Re: Left hand or right hand thread?
you might think about using double nuts as it is possibly the cheapest and easiest to make and maintain, doesnt put any wires in the way, doesnt obstruct the the spindle bore, doesnt use any expensive or hard-to-find parts. RH is fine and can be maintained fairly easily for this use. there should be very little shock or high-frictional-torque load on the left side threads so self-tightening or loosening should not be a big problem.
if you make a washer of a thin steel, say .030 or so, tighten the first spindle nut to the correct amount, place the washer on the spindle and then tighten the second nut. Now peen the washer's protruding edges over the flats on the first and second nut - alternating around the spindle. this will lock the two nuts together, is easily removed, and is easily replaced with a new one. if there are any sharp edges sticking up you can peen or file them down so that they dont present a hazard. no threadlocking goop required, or any special wrench to hold the spindle while removing them. BTW if you have a third nut you can always run it and number two ( backed off a few turns) together and jam them, to give you another place to put the wrench when you are trying to get spindle nut #1 loose. put the first wrench on nut #3 which is jammed in place against #2, then the other wrench on nut # 1 and pull the wrenches together to loosen nut #1. this is way better than jamming the spindle by holding something in the chuck or by jamming any spindle gears.
if you make a washer of a thin steel, say .030 or so, tighten the first spindle nut to the correct amount, place the washer on the spindle and then tighten the second nut. Now peen the washer's protruding edges over the flats on the first and second nut - alternating around the spindle. this will lock the two nuts together, is easily removed, and is easily replaced with a new one. if there are any sharp edges sticking up you can peen or file them down so that they dont present a hazard. no threadlocking goop required, or any special wrench to hold the spindle while removing them. BTW if you have a third nut you can always run it and number two ( backed off a few turns) together and jam them, to give you another place to put the wrench when you are trying to get spindle nut #1 loose. put the first wrench on nut #3 which is jammed in place against #2, then the other wrench on nut # 1 and pull the wrenches together to loosen nut #1. this is way better than jamming the spindle by holding something in the chuck or by jamming any spindle gears.
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Matt_Isserstedt
Re: Left hand or right hand thread?
What gmacoffline is saying is right on.
I was going to throw out that a commercial solution is a Whittet-Higgins nut and lockwasher.
http://www.whittet-higgins.com
The design of this ring (or nut) and lockwasher is twofold, keep the nut secured, and allow precision adjustments to opposed tapered roller bearing sets such as in a quill or lathe spindle. There are 4 slots machined into each "nut" each offset slightly more than nominal and with the fine threads, the nut can be twisted something on the order of 1/64 of a turn to engage a new locking washer tab. As Forrest Addy pointed out a long while back, tweaking the locking collar tabs slightly with a hammer and punch can get you even finer resolution than that.
Check with your local power transmission house, they were quite reasonable on the order of $25 last time I bought a set.
Hope this helped.
-Matt
I was going to throw out that a commercial solution is a Whittet-Higgins nut and lockwasher.
http://www.whittet-higgins.com
The design of this ring (or nut) and lockwasher is twofold, keep the nut secured, and allow precision adjustments to opposed tapered roller bearing sets such as in a quill or lathe spindle. There are 4 slots machined into each "nut" each offset slightly more than nominal and with the fine threads, the nut can be twisted something on the order of 1/64 of a turn to engage a new locking washer tab. As Forrest Addy pointed out a long while back, tweaking the locking collar tabs slightly with a hammer and punch can get you even finer resolution than that.
Check with your local power transmission house, they were quite reasonable on the order of $25 last time I bought a set.
Hope this helped.
-Matt