Gears still dont engage ....... driver gear spins but doesnt meet with main gear ffs
#Motorised Throttle Unit
digital topaz
digital topaz
yup and cant get the motors any closer in as theyt hit the other throttle gearing if i do
cold patio
yup and cant get the motors any closer in as theyt hit the other throttle gearin...
I guess you need to make new larger gears.
digital topaz
i mean ive got 2 larger gears but its seciring them on the stepper thats the issue
cold patio
Does the stepper move in the correct direction and amount, as expected?
proud trellis
a printer does have some use in this hobby yeah
digital topaz
deffo lol miss mine now
The bores in these gears are too big .... thinking of melting a nut into the centre then fill with solder ?
digital topaz
So git some hubs that have a screw to the stepper shaft 🙂 should finally get done now .... nownto find how I can get the parts I forgot to 3d print gmfor my yoke sorted lol
proud trellis
🙂 always something to do, this hobby has that
digital topaz
@proud trellis @cold patio deffo game over ...... ive rebuilt it all bigger gears etc etc ..... can only get the spoiler motor to work thge other 2 just click so deffo gonna call it a day i think
cold patio
Consider maybe larger gear on the lever and smaller gear in the motor to increase torque.
Are the levers that hard to move?
Maybe 2:1 gear ratio
digital topaz
not meg hrd to move no .... nd i tried smller gers but couldnt s the steppers were then too close to the hndle ger //// so ive snipped the wires and ill ju8st keep em on for resistnce i guess
cold patio
The idea I had was that the smaller gear would go on the stepper and a proportionately larger gear goes on the lever, to increase the torque from the motor, such that the distance between lever axle and motor axle remain the same. Torque could be increased by twofold that way.
if you already snipped the wires, then not much else you can do.
well, can we close this thread then?
digital topaz
the gears for the4 levers are an actual part of the lever they arent seperate unfortunately
digital topaz
my only other idea is to take out the steppers ... mount below aand add an extra set of gears @cold patio ?
its not exactly like this but gives an example of how the gears are built into the lev er#
cold patio
I see a four-gear reduction. Is that what you have?
Coupling the motor to the same gear chain should provide with a large increase in torque.
digital topaz
No mine was originally a servo with a gear on the shaft direct to the gearing in the lever ... now its the same but obviously a stepper
I'm thinking of putting a gear below the levers ... then attach the steppers to that with a small gear on there ... that's should increase torque right ? The gearing in the levers are large then ill add a medium in between and a small on the steppers
I strangely can't find anything on the exact throttle I have lol
cold patio
You only gain torque if the gear in the motor is smaller than currently
or the gear on the lever is larger, or both
or if you make a two stage gear chain like in the picture
In the picture there would be torque gain in each reduction stage.
Only one intermediate gear does not increase any torque.
motor small gear - large gear - small gear - large lever gear.
digital topaz
So going small on motor medium intermediary large on lever won't help ?
cold patio
So going small on motor medium intermediary large on lever won't help ?
only if you are actually reducing the number of teeth on the motor gear.
and the torque increase depends only on this. It is irrelevant how many teeth the intermediate gear has.
digital topaz
Yeh the gear I'm gonna use on the middle on is currently on the motor the new motor one is smaller
The one I'll be adding to the motor is about a quarter of the lever or a third the middle ine will act more as a link as I can fit the smaller gear in and get the steppers in place to the lever as the steppers collide with ither peripherals
I'm also going to replace the plastic shims you can see on the rods with actual bearings to further help against friction
cold patio
do you have space to do a double layer gear like the one in the picture? That would really increase torque.
ok, if the motor gear is about one quarter the size of the lever gear, you have a roughly 4 to 1 ratio in torque.
digital topaz
I've tonnes of space underneath just means making new brackets etc and purchasing new gears
digital topaz
I shall give it a go tomorrow 🙂
cold patio
you really work late, don't you? it must be 3am in UK
digital topaz
2am it was lol
cold patio
and this is the stepper being fed 12V in full step mode???
digital topaz
Custom stepper send driver mode
I've the same drivers and motors as you bro
You think it could be an amp issue ?
cold patio
I fed 12v throught the A4988 driver to the stepper
digital topaz
Yup I've got the exact same 12v on an external source
cold patio
does the stepper move without any stutters when not put on the gear mechanism? I am just trying to determine if this is really an issue of overloading the stepper or wiring issue.
digital topaz
Yeh they move freely
cold patio
if the stepper alone stutters, the wiring is most likely inverted somewhere.
digital topaz
No they run perfectly when not on the throttle mechanism
Surely it's gotta be more powerful than the little servos that used to run it ?
cold patio
and you configured the A4988 for full stepping mode?
digital topaz
Erm 2 mins ill get a screen shot
cold patio
servos can be pretty strong too.
digital topaz
My drivers run thru a cnc shield board but can't see that making a difference all that does is means I don't have ti solder or jumpnlead to the driver
cold patio
I didn't use a cnc shield. I imagine you are correct.
digital topaz
cold patio
are the lever gears free to move? can you manually push the teeth to move the lever with maybe a flat screwdriver?
that would also give you an idea of how hard the torque needs to be.
cold patio
maybe the current is adjusted too low on the driver board
the motor can take up to 1amp per coil
there is a procedure with a voltmeter to adjust the little adjustment screw on the A4988. did you do that?
cold patio
it is explained well enough in the lastminuteengineer web page
if the driver doesn't crank the amperage high enough, of course there will be lack of power in the motor.
digital topaz
i didnt follow that page ?
cold patio
I think I already linked this page a couple of weeks ago. I found this to be more helpful than others...
https://lastminuteengineers.com/a4988-stepper-motor-driver-arduino-tutorial/
this is the part where they explain how to adjust the current
digital topaz
yeh never seen that page just been reading ...... wonder how low mine are lol
digital topaz
I'll sort those tomorrow then 🙂 fingers crossed it makes the difference ... I'm guessing they're set pretty low to begin with ?
cold patio
for 1 amp limit, you would be looking at approximately 0.4 v on this test.
IIRC, I set mine to about 0.38V
digital topaz
What are they set at from factory?
cold patio
What are they set at from factory?
no idea
you need to look up what is the current rating for your Nema17 motors and do the adjustmente based on that
mine are rated at 1amp
digital topaz
How do you calculate it ?
digital topaz
350 Ma
digital topaz
So .14
cold patio
so, you would be looking to adjust to 0.14V like it is shown in the tutorial.
digital topaz
Ok
digital topaz
Just checked mine @cold patio @proud trellis and they're showing at between .34 and .54v could this still be why the motors are clicking ?
proud trellis
at least on my 3d printer extruder the motor will click if the filament is trying to push when it is stuck, or if you try to push it too fast
so I would guess the clicking might be that the motor is struggling - but I have not used steppers for this kind of use myself, only for gauges where the forces are always very small
digital topaz
the uno just burnt out ffs
cold patio
I also believe the clicking is caused by the motor not being able to overcome the torque required to turn the gear.
However, If the voltage reading was 0.34 to 0.54, then the driver was putting out max currents which, according to the tutorial, are in the range of 0.85A to 1.35A. That seems to be too high for your motors.
cold patio
the uno just burnt out ffs
How did the Uno burn out?
digital topaz
Faulty driver ... was testing the 2 pins and it started smoking