Stepper motors making horrible noises.

Having got my firmware sorted out,I thought I'd try and calibrate the endstop settings.
To my disgust,the steppers all make horrible grinding-like noises,without actually moving.
I have put the 2 z motors in series,as recommended.
They move,making those noises ,but don't stop when hitting the end stop.
I've done a bit of searching online,and some people suggest that the connectors on the board may not be fully home.
I'm beginning to believe that may be the problem.
I bought a supply of Dupont style crimp connectors from China,including 1,2,and 4 way sockets.
It seems it's very difficult to crimp them in exactly the right way.I've noticed on some connections,the crimped part gets pushed back up out of the socket.
I'm using the correct style crimper,which in fact does a nice job,it,s just that the connectors themselves don't seem to be up to par.
I'm going to have a rummage in my stock of computer wiring plus connectors,to see if i can find some better sockets.
Then i'll cut off the Duponts,and solder the proper connectors to the wires.
Just as an aside,these motors all worked faultlessly before,having screwed connections to the Melzi board.
Hence the uneasiness about those Duponts.
What type of connectors do you guys use with a ramps board?
I think the ramps pins use 2.54mm spacing .Fairly standard,i thought.Maybe not.

It may have been the connecters,it may not.It seems the pinout on the ramps board is in a different order to the Melzi.
Anyway,I replaced the dupont connecters with some old 4-way computer ones i had lying around,and bingo,smooth running motors.
But on reflection,I could have simply swapped the pins on the duponts,and it probably would have worked.
The wire colours are a weird mixture now,but at least they're in the right order.
Next job is calibrating the end stops.F.I.,the x-axis stops somewhere in the middle,and pronterface says "end stops hit 1.7"
Thats just an example ,it wasn't necessarily that exact number.
The steppers also seem to make a soft,but very high pitched whine once they stop moving.

hmm,just found out that the end stop connections to the ramps board are polarized.
Makes perfect sense now i think of it.I may well have some reversed.
Will check tomorrow.Have x-y-z axes working after a fashion,but extruder is still no go.
Tried to print a test cube,but nada,zip,nuffink.to be continued......


Oh,another thing,don't buy the Dupont-style connectors from china.They are crap.
The locks often do not lock,causing non-contact inside the socket.When you plug them in,
the pin on the board simply pushes the connector pin back out.Caused me no end of grief.

good to see you got the motors sorted. as to the motor whine, this is normally due to the trimpots being set a little too high. turn the trim pots down (WITH THE PRINTER OFF, no power, not connected to US and then connect again and move motors, you want to get them down to the point that they no longer move, and then turn them up just enough to get the moving.

my Z still makes some noise after it stops but the others only make noise when they move and it's pretty quiet when it's moving.

Standard locations for endstops on the prusa I3, standing facing the printer the X endstop will be on your right, the Z can be on eihter left or right and will be at the bottom.
Y axis will be at the farthest side away from you.

In regards to Dupont style connectors,

I have just crimped approx. 100 (combination of male and female pins) on a wiring harness for my Openbeam CoreXY build. All motors and sensors are running and no issues with pins pushing out
Some pins were soured in NZ, others from China. Found no real difference between them.

I think it mainly comes down to the size of wire, size of the insulation of the wire, the crimp tool and the crimper person when using these Dupont connectors.

With the female pins you need to make sure that you don't have too much wire going into the socket area. Strip only 3 mm back, any more there won't be room for the male pin to insert and this will force the female pin back when connected. Sometimes best to use scissors to trim up the wire rather than side cutters.

The other thing I found with the crimp tool I was using that with the female pins you need to make sure that you don't damage the female pin part that the plastic housing clip makes contact with. This stops the pin locking in the housing.
I found that it was best to use a pair of small long noise piers to partly crimp the wire onto the pin and also partly crimp the insulation before using the crimp tool.
With the male pins I found it best not to snap them off the metal strips but just cut the metal strip between the pins and this allowed good alignment on the crimp tool, you then can snap them off the metal strip afterwards. Found male pins a lot easier than females pins to crimp.

If using large wires it can be hard to slide the crimp pin into the plastic housing, sometimes you need to use piers to make the crimp around the insulation tighter. Normally the pins should slide in easy if the wire size and crimping is correct.

Also found the crimping tool I was using was crimping too hard and had to set it to the minimum setting which was to flip the adjuster and then rotate it to the minimum crimping position.
When crimping with some larger wire or 2 wires I also found it best not to go all the way but to release the ratchet mechanism.

Always buy more DuPont pins than you need as it takes a bit to get good at crimping.

And use a good pair of glasses to see what you are doing..

Cheers