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Has anyone here tried these extruder upgrade assemblies ?
I think they will fit all printers with nema-17 stepper-motors in extruder.
Found them on eBay.
Thinking about trying a set on our CTC.
Hoping they will be easier to clean and maintain ?
Click picture for larger view:
Attachment 7553
Oh well, No one seems to know anything about these extruders, from the UK.
So, I'll go ahead and order them to Test them out.
You Knew I Would didn't You ! ;)
Well, I got these extruders after almost 2 weeks
and found problems with them.
The stepper-motors just click and will not Turn! :(
The motor shafts are about 1 centimeter Too Long,
and there is No flat in shaft for the set-screw.
Both motors received do the same thing, so it's not just a single defective motor.
I do know that not all Nema-17 motors are made the same internally,
and some require higher voltages and currents than others.
So, I think the problem is that these motors do Not match the settings in printer's Firmware.
The CTC motherboard does not have adjustment pots, like some older printers did. :(
If changing Firmware is the only way to get these motors to operate,
then they are Unusable in our printer ! :(
I would not mind modifying the motor-shafts, if I can get them to operate.
I will install the extruders on some good motors though,
and see how they operate, after I get this problem resolved with the Seller.
Check your start Gcode. You can change the current with G130.
If you have a line like (for example) G130 X127 Y127 A127 B127 in your start.gcode then your current is maximum already. The value is a 7 bit number from 0 (no current) to 127 (max current)
Yes, but the problem is that we are using Makerware-2.4 Slicer softwareQuote:
Originally Posted by Mjolinor
and do Not have access to G-code. :(
I has it's own code format and it does not include anything about stepper-motor control,
that I can find :(
Firmware is not compatible with any other slicers I've tried, except for Rep-G. :(
I tried to test motors using Replicator-G slicer, but had problem with Python-interpreter.
Python must have got corrupted some how ??
Maybe I can use it to test, but will need to reinstall Python, to get it working again.
And I really don't want to do that, just to test these motors ! :(
Since motors are Not working with the set-up we Have and want to Keep that way.
I'll probably keep these steppers for a robotics project I've been planning,
using an Arduino kit controller board.
Just too much trouble to try to send them back for a refund ! :(
Since they are part of a kit and I want to keep the other parts in kit.
But now I'm concerned about how I can determine which Nema-17 motors will work in this printer
and which will Not, if I ever need to replace a failed motor ???
They all Look similar but evidently have Big differences Inside ! :(
The seller thinks the motor Connectors are wired differently ! :(
I'm certainly not going to change wiring in our printer
to try to match connector wiring in his motors ! :(
And I doubt they can be changed Inside the motors . :(
You cannot change them inside, opening it buggers the motor up. The wiring is not likely to be different but is easy enough to check with a multimeter.
I'm thinking they may have reversed polarity of windings, inside the motor,Quote:
Originally Posted by Mjolinor
not changed which pins go to windings.
So, if that's true then the pins would look the same to an ohm-meter ??
Yup, but it would rotate a different way and only if one were changed and one wasn't if both are changed then it will behave the same.
?????? Now I'm really Confused ????? LOL ;)Quote:
Originally Posted by Mjolinor
I think some printers are wired to match the way his motors are made,
but our printer is wired for a different motor wiring design.
(Even though they are All Nema-17 motors)
And how to determine where to get the Design to match our printer's wiring, is the Big question now ???
Well the sellers of this extruder kit, who are in the UK,
called : 'We Do 3D Printing',
have not been much help in resolving the problem with their stepper-motors. :(
Only said they think problem is with the connector wiring being different
and no more replies about helping with a solution, refund or replacements.
Needless to say I'm very Disappointed in this purchase ! :(
I just hope they find the problem before selling these useless motors to anyone else.
I got a message from Seller and he said that it's the center 2 wires that are reversed, inside stepper-motors,
( AXBAXB instead of AXABXB like ours )
He found that his motors will Not work in Many printer makes, CTC, Wanhao, FF, etc.
But will work in other makes, like the RepRap.
I think I'll take one apart and see if it can be changed internally.
Since they are Useless the way they are now, for our printer. :(
That is really odd. Must be a faulty batch, it has to be. No one would make them like that deliberately.
No, they are 2 different designs of motor internal connector wiring.Quote:
Originally Posted by Mjolinor
Not just a bad batch.
Why and How it happened would only be guess-work for me !
Stupid question time.
You did make sure you bought 24v and not 12v.
I have bought lots of stuff for my CTC 3dprinter from We Do 3D Printing with no problems at all. I haven't changed the stepper motors on my printer as the originals worked fine, but I did change the extruder to the ones like in your picture and it made a big improvement over the factory fitted ones.
Well, the way I understand it is that stepper-motors are Not rated at a fixed voltage,
like 12 or 24 volts,
but are rated at a voltage Range, like 3 to 25v or 5 to 30v, etc.
and usually only the minimum voltage rating info is given , like 3 or 5 volts.
So they should operate on a higher or lower voltage, as long as it's in that Range of voltages.
I've not tried their extruders yet, since the old ones are working great now,
but I plan to soon.
Thanks for the Info,
Note: I have verified that seller is correct about there being 2 versions of connector wiring in Nema-17 motors
I did say "Stupid Question Time" as i don't know much about these things at all. I just know that the CTC printer uses 24v for things wheras some of the others use 12v. :) Luckily I have not had to change any motors in mine yet I'll have that fun at sometime I suppose though.Quote:
Originally Posted by EagleSeven
I did try to completely rebuild the hot end and extruders with parts from DealExtreme (very cheap chinese same as the printer :) ) but the distance between the screw holes on the carriage and the metal block were different on the one I bought as it seems the dimentions are not quite the same as the makerbot or flashforge. So i plan on printing a new carriage at some point.
I got one of the stepper-motors to operate normally by reversing the 2 center pin connections,
inside the motor.
After removing motor's back cover, I cut the 2 center etch lines on the PC board.
(Don't loose the bearing spring-washer)
I then soldered in 2 small insulated wires between etch and connector pins,
in a X shape.
I have 2 more motors that I plan to do that to,
when my eyes and nerves have recovered from doing this one ! LOL ;)
Note: To do this you need a very small-tipped soldering-iron and a Magnifier-hood
I now have both these extruders installed in our CTC and they are working Great !
and since I now know how to fix the reversed stepper motors 'I'm All Happy Again' ! ;)