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hesketh
04-13-2007, 04:36 AM
Would it make sense to add a blast relay to the brake circuit for scale racing in order to minimize the resistance in the circuit and therefore improve braking? Besides adding a trigger post on the brake side would there be any thing problematic about the wiring ?

Paul

Slapshot
04-13-2007, 07:10 AM
Paul:

It is involved but.....
Yes a relay can be used. It has been already done. It is considered a medium speed mechanical brake. (Electronic is high speed).
Just make sure your relay is close to the track terminal to take advantage of its purpose. Then you will only need a two small guage wires going to your controller. The red wire would be eliminated to the handle and connected to the relay near the terminal. Wiring for the actual brakes is through the relay output terminals. The brake button is isolated and only acts as a switch.

Downside... If you use a resistor for your brake trimmer it will have to be near the relay output to the track red. That is to take advantage of the cuircut. So adjustment will be more difficult. You would have to reach down to the panel to adjust brakes.

Unless.....you use a transistor trimmer. Just for a very very simple example you can gut a old unused 10 band electronics controller to make a external brake trimmer cuircut. You will need the senativity controll and a low end stablization resistor in the range of say 50-80 ohms plus the transistor and heatsink. The senitivity trimmer becomes the variant for brakes(think of it as similar as the network for the wiper on the trigger). With this you will need two thinner wires to go to the secondary brake transitor from the senativity trimmer pot. Brake pot would be on the controller as before. Obviouly if you know the resistor values and the type of transistor to use you won't need to gut an old controller........

A electronic version with out a mechanical switch (relay) would be simpler and much faster.

Take a look at a blast relay on say a difalco and the wiring would be the same. Except on the brake side.

Food for thought. Technically you would not need the red, white and black thick wires going to the controller handle at all. If you think out your wiring correctly. Just a loom of smaller thin wires for the transitor cuircuts,switches and relay.For obvious length of writing I will not elborate.


Raymond

Dan Ruddock
04-19-2007, 07:23 AM
Also you should use the normally closed contacts on a SPDT relay for the brake connection that way the relay does not have to be powered for the brakes to work. If you do it the other way there will be no brakes when the power is turned off. Dan

RomanK
04-19-2007, 01:26 PM
use the "NO" set of contacts, stick a cap and an LED in the circuit and call it "NEW'...."INNOVATIVE"....."AMAZING":p

bet I'm gonna get told to "button up" ;)

Bill Fulmer
04-19-2007, 01:47 PM
bet I'm gonna get told to "button up" ;)


I am sure that will be the nicest thing said to you!;) :eek:

HurricaneLarry
04-25-2007, 05:44 AM
I just use a 12 volt battery in my braking circuit, this way when I go to a track and rent 15 minutes track time I can still drive the car once my time runs out, and the poor schlep that sold me the 15 minutes never knows.

ohh and the 12 volt battery works well with providing reverse polarity voltage for braking whether powers on or off.


Ps: does anyone beside Roman, know what actually causes the braking on a slot car track, and why such complicated design have been used to call something so simple inovative just to sell controllers.

Gee guys some of us weren't tossed from a turnup truck yesterday you know...


Roman, Button up

HMMRC44
04-25-2007, 10:52 PM
Seriously guys, who does actually know how a car stops and goes? Could anyone explain this one to me?

Jonathan

HurricaneLarry
04-26-2007, 09:55 AM
Take your brake wire off and the car will roll, put the brake wire back on and the car will stop ...the reason is cause the Brake, although it is a red wire and normally used for power in this case is actually a ground. Now when you have the car on the track there are two contacts or braid, one negative and one positive which are fed to the track via your controller, Black is always power to the track coming from your controller from the panel and the white lead at the drivers panel is the HOT power lead or positive in and this is where the hand controller comes into play. With me so far??? :eek: Ok, the Brake wire completes the ground loop for the motors generated voltage thus causing drag or resistance within the motor causing it to slow or brake. As some of us know motors are also generators, and it is the generated power that aids in braking due to the fact that you have completed the circuit loop back to ground, the motor even off power still turns and provide a positive voltage flow, put it to ground and you have brakes, adjust that ground with a fancy circuit, polarity controller of some type <<<<insert your favorite control manufacturer here>>>> and or potentiometer and you have adjustable braking circuit.

Any planner description and it may not make sense at all.

Hope this helps all you out there that may have wonder why we have three wires and only two braids.


Ps: the cars goes when you pay for track time, hook up your controller place the car on the track and pull the trigger. and if it don't go then, better bring it to the counter for repair.

< this is where Doug and the gang at PJR or any raceway step in>

HMMRC44
04-26-2007, 09:54 PM
Thanks Larry,
But how does the electricity put into the car actually translate to forward motion?

Jonathan

Dan Ruddock
04-26-2007, 11:04 PM
Two magnets repelling each other. Dan

Slapshot
04-27-2007, 01:25 AM
:D

Raymond

HurricaneLarry
05-01-2007, 07:04 AM
Thanks Larry,
But how does the electricity put into the car actually translate to forward motion?

Jonathan

Jonathan, you are aware that these are fixed magnet motors in these cars right? Well, motors have three basic parts, an armature, or stator, a fixed field of magnets both north and south, and brushes with springs. Of course there are all the rest of the parts that are needed as well. but when you energize the polls of the arm with voltage from the track, as the electricity flows through the arm, it creates a magnetic force, it is the opposing forces that translate to motion, and in this case the motion is the spinning of the arm, connect that to a gear, axle and some tires and there you have it, forward motion.

forward motion 101....

hesketh
05-01-2007, 08:59 AM
Huh,and I always thought it was just magic. You learn something new everyday.

HurricaneLarry
05-01-2007, 09:17 AM
But today does not look good for me either... :rolleyes:


Hey what new job do you have that DDDDDDDerek was talking about?

DDDDDDerek
05-01-2007, 11:40 AM
:confused:

HurricaneLarry
05-01-2007, 11:59 AM
you Derek, in the USRA post that Doug started

HMMRC44
05-01-2007, 09:59 PM
Thanks for the sensible answer, larry!

Jonathan