Electronic project help

[abunaitoo]

I know there is someone here that tinkers with electronics.
I'm working on a new reloading tool.
Need some direction with a switch.
Here's what I'm trying to do.
I need something that, when I push a button, it will turn the motor on, but I need the on time to be adjustable.
Time would be from one second down to zero.
Time would be adjusted by turning a knob.
Kind of like a momentary switch that the on time can be varied.
The button does not have to be held down. Pushed, and it will cycle once.
Am I making sense????

[sawinredneck]

You want a relay activated adjustable timer from a momentary switch. I understand it, just not sure where to get the parts.

[Steelshooter]

What size motor are you putting the power to? I used this on my case annealer to time the case in the flame. DC 6V 12V 24V 30V Max 8A Digital Display PWM DC Motor Speed Controller Switch found on e-bay

[OS OK]

This comes to mind . . . https://www.grainger.com/category/so...ecatalog/N-r6t . . .
but you need to consider the load you want to control...I think these will only switch a 1 amp load.
There are a plethora of timing relays to be had.

If you want to control a heavy load you might control a regular contactor rated for your load through this relay controlling it's run circuit to the coil.

It's been years since I was in motor control, the new solid state stuff is easy to configure though.

[garym1a2]

they make time delay relays that are adjustable. To properly spec them you need to know the voltage you use and current. SPDT or DPDT, ....
I always use digikey for parts for prototypes at work.

[abunaitoo]

Volt is 1.5
Tiny tooth brush motor.
Time delay relay.
I'll google it.
Thanks

[Boolit_Head]

Sounds like you could do this with a microcontroller like a Arduino as well. Not sure how that would fit your plans though.

[abunaitoo]

Maybe I'm over thinking this thing.
I'll try it without and see how it goes.
Thanks for the help.
This place is great.

[JonB_in_Glencoe]

Volt is 1.5
Tiny tooth brush motor.
Time delay relay.
I'll google it.
Thanks

Most inexpensive "two connection" timers will not function with a low voltage like 1.5v.
Your best economical bet will be to design a discreet component circuit (with a 555 timer IC) around your parameters.

if you are hoping to find a "all in one" device type timer, you will need one with isolated contacts. While they are expensive buying new ones, you can find hundreds of them "used" on the famous auction site.
I used many of these when building industrial control panels in a previous life.
https://www.alliedelec.com/schneider...iABEgJC__D_BwE

[MaryB]

NE555 timer is a piece of cake for this. But it is not precision... small micro like the arduino etc would work also. Time delay relay may not have the precision below 1 second... ebay has little modules for all kinds of electronic stuff too http://www.ebay.com/itm/DC-Motor-Dri...cAAOSwrfVZXJ8o

[MaryB]

Could use the cheap timer board to cycle a 5 volt relay though

Most inexpensive "two connection" timers will not function with a low voltage like 1.5v.
Your best economical bet will be to design a discreet component circuit (with a 555 timer IC) around your parameters.

if you are hoping to find a "all in one" device type timer, you will need one with isolated contacts. While they are expensive buying new ones, you can find hundreds of them "used" on the famous auction site.
I used many of these when building industrial control panels in a previous life.
https://www.alliedelec.com/schneider...iABEgJC__D_BwE

[abunaitoo]

Trying to do it "on the cheap"
I'll see how it works without the timer.
Thanks for all the suggestions.

[6bg6ga]

Sounds like your trying to make a powder trickler that will run for set time. It might work somewhat to get close and then hand trickle to finish. I wouldn't use a motor like the one you have. If that is the case you can always use a larger voltage to control the timed relay and run the motor power thru the contacts. You can use ohms law to calculate the resistor to drop the voltage down to your needed 1.5 volts for the tooth brush motor or you can regulate your motor DC supply down to the 1.5 volts you need. While the timed relays will be close they are not spot on all the time. An industrial timed relay a good one is going to be around $75-100

[garym1a2]

For low cost applications that don't have much power I would just use a "N" channel logic mosfet with a low Vgth. Than setup a simple RC circuit on its gate for turn on. Circuit could be less than 50 cents material.Are you looking to make one part or many? If only one your better buying a completed device. With low voltage and low current it should be easy.

[abunaitoo]

It is a vibrating trickler.
The timer is for the "one tap on the spoon" feed.
"0" to "1" second timer to adjust to different powders.
Still in the paper drawing stage.
Have a bunch of old electric toothbrush.
Tried to change the battery, but I'm guessing they don't want you doing that. It didn't work after.
Just another little project I'm thinking about.