To Knurl or Spline

I have a dilemma about the extruder motor shaft. I am trying to decide if I should put splines on the motor shaft, or knurl it. I have access to a lathe and knurling tool, and the motor is dual shafted. So I could put it in the lathe and knurl it pretty easy. As for splines I would have to build the jig that uses a Dremel to spline it.

So what should I do? I think knurling it would be easier to do.

cheers,
Josh

Taking a stepper motor apart is a decent hassle. I vote worm wheel or cogged belt pulley.

Edited 1 time(s). Last edit at 04/13/2010 02:26AM by JohnnyCooper.

Hi jupdyke,
first you have to look at your tracking-line of the filament.
It has to go straight down.
I wanna use Adrians-Extruder.
[reprap.org]
[shop.conrad-uk.com]#
Look for the picture of `Holzwurm`.

[forums.reprap.org]

And also use two of these parts in the first picture instead of a 624 ball-bearing.(Brass-roll with 624-bearing and o-ring 13x3mm)

[forums.reprap.org]

Erich

Edited 4 time(s). Last edit at 04/13/2010 04:57AM by chris-nobody.

As one of my steppers has a hole down the centre of the shaft, I've been toying with the idea of putting a thread in it, and then putting brass inserts on the end of a screw which is them put in the threaded shaft. The inserts in question are the little knurled nut pieces that you find in most plastic items that are held together by machined screws (knurled so that the plastic moulded around them grips). The only issue is that the shaft of the motor would then be longer, and that would have to be accounted for elsewhere.

Hm, also make sure that your thread is in the right direction, so that the torque from the motor tightens the screw instead of loosening it

All,

Thanks for the advice. I went to the machine shop to try to knurl shaft of my motor. I was never planning on taking the motor apart. I have done that before and it is a huge pain. But the motor would chuck into the lathe without taking it apart because its a dual shaft motor.

The bad news was that the lathe that could hold the motor didn't fit the knurling tool, and the lathe that the knurling tool was on couldn't get close enough to the motor to knurl it. Big lathes are nice, but when you want to do small stuff sometimes the tailstock and tool holders are too big.

So its back to putting splines on the motor.

cheers,
josh

Hi Josh,



[reprap.org]

[www.conrad.de]

Erich

Edited 2 time(s). Last edit at 04/17/2010 07:55AM by chris-nobody.