M3 thread size used on Prusa printers
For the M3 bolts and nuts we use on the printers is the thread size 0.5? I see the M3 has two in the tap and die kits of (.5 and .6).
Thanks much!
RE: M3 thread size used on Prusa printers
The Metric system of taps always uses two taps for every size. The smaller is the starter tap and the larger is the finishing tap. It is not a bad system it works very well.
Tom
RE: M3 thread size used on Prusa printers
So use the .5 first than the .6 and done. Thank you!
RE:
That does not sound right. Yes, there are tap sets which use multiple taps to cut a thread (typically three of them, not two -- pre, middle and final cut). Every tap cuts the thread a bit deeper than its precursor. They are usually marked with different numbers of rings around the tap.
But the "0.5" or "0.6" designation typically refers to the pitch of the thread, i.e. the distance between to adjacent turns. It has nothing to to with pre- vs. final cut. You obviously don't start cutting an 0.5 pitch thread, and then follow up with 0.6 pitch.
The standard threads I am aware of are M3 x 0.5 and M3.5 x 0.6. (That second one is 3.5 mm diameter, 0.6 mm pitch.) Are you sure that you really have an M3 x 0.6 in that kit??
RE: M3 thread size used on Prusa printers
My kit does say M3 .(5) and M3 (.6). They have some kits that way on amazon also. I noticed the sets that do show this have no M3.5 (.6) within the set. So are the (.6) truly M3.5. 🤔 🤔
RE: M3 thread size used on Prusa printers
That's strange indeed. I can find some "M3 x 0.6" taps on Amazon too, but only from overseas sellers. I am pretty sure that I have never come across an M3 thread with a pitch other than 0.5 mm; that's part of the M3 specification.
Out of curiosity -- could you put the two taps side-by-side and compare whether they actually differ in pitch? Over a few convolutions the difference should be quite notable. Maybe the manufacturer is using a non-standard designation for the thread cutting depth instead? But neither 0.5 nor 0.6 make sense for that; the actual depth of the thread grooves is less than 0.5 mm.
If in doubt, just leave the "M3 (0.6)" alone and use the 0.5 tap. 🙂
RE: M3 thread size used on Prusa printers
M3 X 0.5 is the standard.
M3 x 0.6 was used for some Yamaha saxophones many years ago.
M3.5 x 0.6 is a standard
rarely used , reserved for non domestic normal use, medical I think.
RE: M3 thread size used on Prusa printers
M3 X 0.5 is the standard.
M3 x 0.6 was used for some Yamaha saxophones many years ago.
M3.5 x 0.6 is a standard
rarely used , reserved for non domestic normal use, medical I think.
Thanks John! I was not aware of the Yamaha use (as you might imagine). I would argue that, if it uses a thread pitch of 0.6 mm, it's not actually "M3". That standard defines all thread dimensions in loving detail, going well beyond the nominal diameter.
M3.5 used to be more common in the 1950s and 60s, from what I have found in older devices. I think it just fell out of fashion with the increasing desire to streamline inventories. We also used to have M2.3 screws, to bridge the chasm between M2 and M2.5. 🙂 I have not seen those used much in current designs...
