SOUTHORD E100HO -> wanna modify it

[bc]

Hi everybody!

i am new french unlocker on this forum...

I have rece ntly buy my first Electric pick gun, but i have a model with just one switch ...

I am electronician and i just want to know if somebody has try to put a potentimoter between the battery (4.5V) and the motor, for regulate my tension (from 0v to 4.5v) and changing the frequencies-band work...

Thanks by advance (and please excuse my poor english quality )

[Shrub]

It can be done but will void your warrentry on your new gun for a start,

The usual method is to just let go of the button ie keep pressing the button to cycle the pick, adjust your thumbscrew properly and you will soon find a varible speed isnt necassary,

Other than that if you still want to have a go do it, its been done before, ive done it to mine and you will use it once or twice on an awkward day, other than that follow the tips above,

Good luck.

[bc]

Thank you for your answer....


Therefore according to you this modification does not represent big interest?

[toomush2drink]

Wouldnt a pulse width modulater also be effective ? hmm shall have to try.....

[bc]

Wouldnt a pulse width modulater also be effective ? hmm shall have to try.....

Yes man....good idea but you need to program a microcontroller ... A explanation is disponible there :

http://www.i-hacked.com/content/view/138/48/

Figure 14. PWM Voltage Waveforms
For this example we'll assume we're working with a 5 volt DC motor. At full speed the motor receives a constant 5 volts, and of course at zero speed it receives 0 volts. At any speed in between, the voltage cycles rapidly between 0 and 5 volts at a duty cycle (the percentage of time the voltage is turned on) that is proportional to speed. In (a) the voltage is turned on for 8 milliseconds, then turned off for 2 milliseconds, then back on, and so forth. To calculate the average value of a waveform such as this you divide the total on-time for any number of cycles by the total on and off time combined for that same number of cycles, and multiply that fraction by the peak voltage, which is 5 volts in this case. The dotted line in (a) shows the average voltage being supplied to the motor is 4 volts, so the motor is running at about 4/5 of full speed. In (b) the duty cycle is 50 percent, and the motor is running at about half speed, and in (c) the duty cycle is only 20 percent and the motor is running at about 1/5 speed.
In this example, the motor receives one pulse of voltage every 10 milliseconds, or 100 pulses per second. The exact frequency is relatively unimportant so long as it is high enough that the motor cannot respond to individual pulses, and uses its inertia to average them out. A voltage waveform of 200 pulses per second, with each pulse having 4 milliseconds on and 1 millisecond off, still has an 80 percent duty cycle, and would still give an average voltage of 4 volts and drive the motor at about 4/5 of full speed.
Do not confuse the PWM frequency with the RPM of the motor, which is the pick vibration frequency. The two are completely unrelated. The PWM frequency remains fixed, and it is only the shape of the waveform that affects motor speed. Wide pulses are high speed. Skinny pulses are slow speed.
If you want to try and add speed control to your gun you'll find lots of circuits on the internet, some with construction details. Also check out HO gage model railroad magazines and hobby stores. This is not a project for the technically disadvantaged. It probably means adding a cable to the gun and using an external battery. One problem you'll have is that most of these controls are designed for motors that run on 6 to 24 volts DC, whereas the motors in SouthOrd and HPC guns may be running on 3 to 4 volts DC. One solution is to use a 6 volt external battery and arrange the circuit to supply a maximum duty cycle of 50 or 60 percent when cranked all the way up

Too much complex to realize... I prefer try this method :

7. Controlling Motor Speed. If you use a SouthOrd, or Electropick, or even a homemade motorized gun, you were probably taught to pulse the unit on and off so it will vary its speed, thereby maximizing the chances of finding the best frequency for opening a particular lock. The biggest problem with this technique is that the motor might coast through the optimum speed briefly, just long enough for you to "almost" catch it with the tension wrench. That's why Multipick added speed control to their gun, to allow you to concentrate your efforts at feeling the instant of pin separation instead of worrying about cycling the motor. They have an obvious advantage, since power for the motor comes from a source external to the unit where there's plenty of room to add the electronic components necessary.
It is sometimes suggested that simply putting a variable resistor in series with a DC motor is an effective speed control, but that's simply not true. To begin with, the variable resistor must be able to handle the worst case motor current (with the motor stalled), which might be a few amps. The maximum resistance would typically be a dozen ohms or less. Low ohm variable resistors rated for high current (often called rheostats) are not easy to find. If you connected one to a small motor you would probably be able to vary the speed just fine -- under no load. But load the motor down a bit and you may find that it won't start until you crank the voltage up to a certain point, then it starts suddenly and runs faster than you want. Then as you try to turn the speed back down, the motor stalls because it has very little torque at slow speed. Another fallacy is that you can make a good speed control with an electronic component called a variable output voltage regulator. It's slightly better than a series resistor, but still performs poorly at slow speed. The reason for this exasperating behavior is related to the fundamental way a DC motor works, and probably not worth a technical explanation.

So i think put a potentiometer between battery (4,5v) and the motor...


The only difficuly is to find the right value of my potar....

If someone has try yet, please report your value choice///


Just for try with a resistor and report today




Happy to meet electronician lock picker

[bc]

I re-put some pics...

My model is a Southord E100HO, like this one :



But with 3 batteries.



-> The transistor way :




-> The PWM way :

[Shrub]

It is a good site that isnt it,

You could go down the FET controller or microprocessor route but there really is no need (it takes a long time to work out a micro-controller, trust me), a current bump up on a 2 cell motor isnt going to blow your normal vr to bits,

I do think its a worth while mod just not on a new gun,

If you are in electronics cant you work it out yourself? try a 100k for starters, if you are in electrics rather than electronics let me know and i will sort you a circuit out as you will probably need more than just a vr

Wouldnt a pulse width modulater also be effective ? hmm shall have to try.....

very funny.

[bc]

Shrub... your are a king!

I have not understand all (iam stupid frenchy) but i will try immediatly a R100k...

yes i am more in electronical (audio professional in fact) but i am fresh beginner...

But i haven't found any formula for calculate the right value (with a tension / RPM rapport)...



-------------------------------------------------------------------------
So your help is more than welkome!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-------------------------------------------------------------------------



Report in progressssssssssssssss

[Shrub]

V
_ = R

I


V= voltage
I= ampheres
R=ohms

You need to work out the smallest voltage your pickgun will oporate at and the highest being 4.5, you then need to work out the current it draws at the slow speed and at the full speed, you then can work out the size of vr you need to control the motor over that range, you may want to put a diode on there to stop any filteration backwards unless you are connecting all 3 leads,

Dont just stick a r100 on let me work it out for you properly and i will get back to you, i will estimate the current draw,[/code]

[bc]

funny the lesson ... In france -> U, not V... And of course i know this law.... But a colleague this morning remember me that maybe the start-power need to move the picks is not 0+V, but often more... Maybe it's start at 2-2.5v..., before this tension, maybe the motor turn, but not enough for the harm-pick....

ANd other thing : maybe the range for control frequencies is very very fine (like +/-0.5V), or why not 4.2v to 4.3v..................


So.....
I had therefore begun unscrewing the party inferior of my pick gun to test a variable resistor between the cell and the connector of the cell.... AND I FOUND EVEN SIMPLER!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

You
Have
Just
To
Turn
Gently
The
Inferior
Party
Of
Our
Pick
Gun
When
You
Press
In
The
Same
Time
The
Switch
Button
.............................................................
AND YOU CAN CONTROL IT BE a QUARTER-HALF ROTATE, Juste before loose the contact between cell and contactor....

THAT'S WORK SHRUB!!!!!!!

Thanks for Have investigate with me!!!!! Together, with a push back the problem by wanting to short-circuit it...........





In frenchy : MERCI BEAUCOUP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! :arrow:

[Chrispy]

That message was rather nauseating..... interesting..... but nauseating.....

[digital_blue]

That ... was rather nauseating..... interesting..... but nauseating.....

You sounds just like the girls I knew in highschool after I had a date with 'em. Hmm.

db

[bc]

Chrispy... Respecte toi toi-même, et les autres te respecterons, my dear...

[Shrub]

Bc,

Yes you can get start up spikes, big current draws on startup, startup may take .5 amp before the motor will revolve etc etc,

The aim is not to use the varible pot to adjust the resistance and choke the motor to slow down but to control voltage to slow the pulse width down, a pot has to be wired differantly to enable this and involves connecting all three (or 4!!) wires,

If you want to alter the speed of the gun by just using a pot then you can connect 2 legs (the wiper and one side) and try that, any value will suffice as one side will be 0 resistance and the other side maximum, if you get no movement try a smaller value one, if you get no control but the gun runs full speed try a bigger one value one, i would start wih a 100k and go from there,

Remember a pot wired in this way will give next to no control over most of the sweep and then at one end give full control over a few degrees of turning, as you are in audio try a linear pot as they are more stable over the range but will still get the limited performance, perhaps on a 4.5v system it is all you need,



Im sorry but i got slightly lost with your revalation,

Are you now pressing the case hard so that you are touching the moving parts making them slow down? if this is so then STOP IT, you will damage your gun,

If not can you have another go at explaining it for me

[Shrub]

Oh yes and ohms law is differant for you as the word in french for volts obviously starts with U,