Question about steppers

i hope im posting this in the right spot.
i have a 28byj48 stepper motor.
what is the maximum speed and acceleration i should be putting in the code to maintain a decent amount of torque?
im trying to spin a lazy susan and i set the speed and acceleration to 1000 and it stops every time there is any resistance.
or should i be using a bigger stepper? if so, any recomendations?

Is this "direct drive" right off the motor shaft or is there some other mechanism.

i guess you would call it direct drive. i 3d printed a small gear which engages with the inside of the turntable and turns it

i would post an image if i knew how

Stops? What is powering the servo?

Well, I would not be calling it a direct drive. A gear on the motor is driving a second gear. You know the ratio of the motor shaft to the diameter of the gear. And you know the diameter of the gear on the turn table. From that you can compute the actual torque being applied by the motor to the turn table.
The first will be a reduction in torque and the second will be an increase in torque.
Your gears look they would really produce a LOT of friction. Perhaps that is where the trouble lies.

How is the stepping motor being driven?
To get more torque than you increase the voltage, but you use a switching regulator to make sure the maximum current is not exceeded. These sort of things are built into stepping motor drivers.

im using a uln2003. i think thats what its called. and a dedicated 5v 2amp power supply

That is just a Darlington driver so nothing clever about it.
You can run these at 12V if you want.
You motor has a coil resistance of 50R, so at 5V this would draw 100mA per coil.

Therefore at 12V it would draw 240mA per coil. As you should not have more than two coils on at once the uln2003 will just about cope with this thermally speaking. This current is well within your power supplies capability, although I don't know if its voltage is adjustable, however the motor will run warmer.

If 12V will not give you the torque you need then you will have to get an other motor, preferably a two phase one with a proper motor driver.

Or you could run the motor slower, the slower it goes the more torque you get. You will have to experiment with the acceleration / running / deceleration numbers to get what you want.

ok so i upped the power supply to 12v and now it works but i found an issue with my code. im using limit switches and the motor runs till the limit switched is pressed and released. i have to get it to stop when the switch is pressed. didnt even know that was a thing.

Either wire the switch the other way round to what you have, or change what logic level your secret code is looking for.

wire it the other way around? right now its wired to n.o.
if i wire it to n.c. that will work without changing the code?
i ask because i paid to have the code written and havent heard back from the company yet.

Should do.

Didn't you provide them with the switch connections?

i did. bit in their instructions they did not specify which contact to wire to. it turns out i had it backwards. all is working now

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