Thanks Frank, I just finished machining a wedge. Possible if I drive the wedge in and then add vibration it might pop out.
I have about a 1/8" between the spindle and the shank at the max.
You say a pair are you picturing them opposed?
Yes you should use a pair of wedges put in place opposite each other this way you do not run the risk of bending anything also as you tap them in place it is better to tap on each one as equally as possible you can use a clamp to hold more force against them then apply the shock treatment won top of the draw bar or whatever you are using as a last resort a minor amount of heat can be used just a small propane torch would be sufficient but if you use heat have the wedges tapped in tight
and be sure not to heat any one spot it needs to be applied as evenly around the spindle as possible and try not to get it much more than spit fry hot.
I prefer using an induction heat method in instances where I have had things absolutely defy any other means of removal, by raping the part with a non conducting material then winding a few turns of Nichrome wire then connecting to a battery this works well for extremely warp sensitive instrument assemblies where a flame would be disastrous.
Thanks again Frank, I need to get some nichrome wire, I do not like the idea of using a torch.
Boy I am getting all sorts of visions of different grinding setups to make the wedges, but I need to do some ballscrew screw grinding so I need to rig up a grinder anyway. Plus I have the components for making a real simple tilt table, so that is also on my list.
Of course I am not supposed to be working on any of this I do work that has to be done first, my poor 12x36 Craftsman Lathe has been sitting
outside my shop for the past six months waiting on me finishing a corner of my workshop to put the lathe in.
Thanks again I really appreciate all of the (much needed) help.
Ralph Just as a warning these suggestions commits and methods that I have posted are things which I have been doing or have done over the course of decades.
What may be tried and true for me and may seem like simple procedures to others as well often are not without unexplained complexities.
using induction heat with the nichrome wire around the spindle may sound like an easy solution. However if this will be your first attempt at using induction heat around a cylinder I recommend extreme caution should you even attempt to do so. Things can get out of hand as fast as your rolling jacks moved on you.
there are many sizes of the wire and depending on total length per volt applied it can go white hot very quickly and if it gets white hot and happens to burn into it could burn through what ever heat resistant insulation and deposit itself to the spindle. making a coil large enough that it leaves an air gap between the loop and the spindle would actually be better.
Before going out and buying a coil of this very expensive material do yourself a favor look up making of an induction heating device
You may find that for your purpose all you will need would be some heavy gauge copper transformer wire wrapped around the spindle several times.
A good variable resister and a knife switch for a disconnect is handy for control
if you have ever tried cut a glass bottle by wrapping wire around it you should have an idea of the care needed in doing something like this.
TRY EVERYTHING ELSE FIRST USE HEAT AS A LAST RESORT
Good luck I wish I was the one removing it for you
ralphxyz is fortunate. Toppling machinery can be disastrous. Everything depends on stability. The mill is pretty tall assembled, the cabinet is sheet metal and offers little counterweight. We are at some fault, not recommending the casters placed at the greatest distance between possible.
Virtually ALL machine tools have a high center of gravity, even lathes. Owners want small foot prints to save space and ease cleaning.
Riggers have to contend with that, often slinging instead of lifting. Most nervous period ever endured was lift of my lathe to trailer to move across country. Reliable guys from good company, but NO insurance settlement could or would have amended loss of that particular machine. I'm not very materialistic; took years to find what I wanted, and she is it.
Yes, the same girl and lovely profile you see to the left. In slings, no less, she's kinky that way.
...we'll learn more by wandering than searching...
Thanks for posting about this machine tipping. There is a trend in forums (and of course more broadly in life) to under-report the occurrence of catastrophic events, despite the fact that the knowledge gleaned from failures is often more valuable than that gained from successes. This behavior falls under an umbrella of various related cognitive biases: positive outcome bias, file drawer effect, publication bias, reporting bias.
Right on, Jon. Ever since childhood I've thought badly of such bromides as...
Think positive (stupid sentiment and bad English)
Look on the bright side
Everything will work out
Don't dwell on your mistakes
Trust in (insert deity of choice)
because it seemed that, the more I analyzed and corrected my mistakes, the better things went.
At least the British wartime injunction "Keep calm and carry on" didn't contain any assurances that "carrying on" would work.
I think all of us here have a responsibility to not only report our own screw-ups, but also to point out dangerous setups and practices when others reveal them. Any annoyance the latter may cause is far outweighed by the satisfaction of perhaps saving someone from harm.
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