999zip999
100 TW
Go get a plate of Steel a 4in grinder with cutoff wheel. Make a template get some chalk or a soapstone and a vise. Weld on two nuts and drill one out.
Chalo said:Buk___ said:In the thin axis, these springs are capable of being wound tight, and stretched flat and back again many millions of times. Each infinitesimal section of metal can be flexed though 20°. 30°, 90° or 180° without harm.
Flat springs are thin throughout their lengths. Your TA is "thin" (not in absolute terms, but relative to the whole) in a single spot on each side. You'll get material failure there as soon as static friction is overcome and the thing is called upon to do something.
999zip999 said:Go get a plate of Steel a 4in grinder with cutoff wheel. Make a template get some chalk or a soapstone and a vise. Weld on two nuts and drill one out.
Buk___ said:Chalo said:Flat springs are thin throughout their lengths. Your TA is "thin" (not in absolute terms, but relative to the whole) in a single spot on each side. You'll get material failure there as soon as static friction is overcome and the thing is called upon to do something.
What you are suggesting is that if I take a piece of spring steel and apply a force to it as the green arrow below left, it will bend and return as any spring, but if I apply the same force to the same material in the direction of the red arrow, it's suddenly going to become fragile and break.
Chalo said:What I'm pointing out has nothing to do with materials properties but everything to do with your part shape. You can't put a narrow neck in the middle of a piece that's loaded in bending without causing stress to concentrate there. If you put a much thinner spot in the middle of a flat spring, it too would permanently bend or break at the thin spot.
Chalo said:If you can't tell the functional difference between an entire loop of flat spring added as a feature, and a localized thin spot created by cutting a slit partway across a plate, I'm afraid I can't help you.
Make one and test it to failure with a torque wrench. See for yourself what you can't seem to understand otherwise.
Buk___ said:The design I posted is such that the jaws are the same diameter as the axle nut flange -- based on those supplied with my motor -- so if the flanged nut fits inside any lawyer lips (my bike doesn't have them), so would the jaws.
Just to be clear (since Im always trying to learn much more about mechanical engineering types of stuff and so follow all of these types of threads, but I get lost sometimes in them, requiring many re-reads) are you referring to this post?Buk___ said:In your last post you mentioned that the hardness of the materials that the Nord-Lock was in contact with [paraphrase] was critical, and went on to list those as "the torque arms and axle".
Alan B said:The rocking back and forth of acceleration and regen seems to defeat star (and most other locking) washers and requires wedglock type washer (such as NordLock) to prevent loosening. These require the surfaces they engage (nut and torque arm in this case) to be softer than they are to work properly.
You can't just go putting notches and sharp corners on parts that are stressed in tension. When you do that, you're telling it exactly where to fail, and to do it quickly
Chalo said:it's plain to anybody with mechanical engineering chops.
amberwolf said:Just to be clear (since Im always trying to learn much more about mechanical engineering types of stuff and so follow all of these types of threads, but I get lost sometimes in them, requiring many re-reads) are you referring to this post?Buk___ said:In your last post you mentioned that the hardness of the materials that the Nord-Lock was in contact with [paraphrase] was critical, and went on to list those as "the torque arms and axle".
Alan B said:The rocking back and forth of acceleration and regen seems to defeat star (and most other locking) washers and requires wedglock type washer (such as NordLock) to prevent loosening. These require the surfaces they engage (nut and torque arm in this case) to be softer than they are to work properly.
If so, then Im not sure if one of you said nut and meant axle, or the other said axle and meant nut, or if I really missed the point and its something completely different.
amberwolf said:Buk___ said:The design I posted is such that the jaws are the same diameter as the axle nut flange -- based on those supplied with my motor -- so if the flanged nut fits inside any lawyer lips (my bike doesn't have them), so would the jaws.
Many motor axle nuts dont have any flanges, or any kind of ribbing/etc on any side of them (completley smooth otehr than the threads inside), though they often come supplied with flat washers, which may or may not be small enough diameter to fit within any lawyer lips on dropouts front or rear.
Doesnt matter if this isnt intended to be a (semi-) universal solution, but if it depends on a certain diameter / type of axle nut (im not technical enough to be sure from what Ive read here so far), then that nut would need to be supplied with it to ensure proper operation.
spinningmagnets said:You can't just go putting notches and sharp corners on parts that are stressed in tension. When you do that, you're telling it exactly where to fail, and to do it quickly
Chalo, you sound like you may have some legitimate concerns, could you throw together a quick and dirty drawing of what you consider to be a useful shape, one that is close to what the OP is trying to use?
fechter said:Any torque arm that is C-shaped will have a strong tendency to spread apart.
fechter said:A full circle around the axle is much more likely to survive.
fechter said:I like the concept of clamping the axle by tightening the axle nut so there is no free play. Especially if you have regen the free play will tend to work the nuts loose.
Alan B said:There's not much point in arguing about it, only testing can prove anything. Build some and fail them with a torque wrench, as Justin has done so many times.
Chalo said:Alan B said:There's not much point in arguing about it, only testing can prove anything. Build some and fail them with a torque wrench, as Justin has done so many times.
What I'm sayin'. I don't have to prove the design is bunk; he can just try it out and see for himself.
AFAICT, searching his posts for the word axle and rereading this thread, tahts what he did say (though he did not use the word axle, only the word nut), and that was why I asked the question because I was confused since he appears to have actually said what you think he should have said.Buk___ said:I also thought -- and mentioned obliquely -- that Alan_B may have misspoke when he suggested that the axle needed to be softer than the nordleck washer for it to work. I'm pretty sure that instead of "the torque arms and axle" he should have said: ""the torque arms and axle nut".
amberwolf said:Just to be clear (since Im always trying to learn much more about mechanical engineering types of stuff and so follow all of these types of threads, but I get lost sometimes in them, requiring many re-reads) are you referring to this post?Buk___ said:In your last post you mentioned that the hardness of the materials that the Nord-Lock was in contact with [paraphrase] was critical, and went on to list those as "the torque arms and axle".
Alan B said:The rocking back and forth of acceleration and regen seems to defeat star (and most other locking) washers and requires wedglock type washer (such as NordLock) to prevent loosening. These require the surfaces they engage (nut and torque arm in this case) to be softer than they are to work properly.
If so, then Im not sure if one of you said nut and meant axle, or the other said axle and meant nut, or if I really missed the point and its something completely different.
amberwolf said: