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 Post subject: Re: Brake Light Switch
PostPosted: August 15, 2016, 2:11 pm 
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Joined: April 12, 2012, 11:56 am
Posts: 662
Location: Pemberton, BC
Some good points raised, guys.
I have a Wilwood pedal with balance bar, installed an inline pressure switch and the residual pressure valves. I've installed the switch into the rear circuit, thinking that a switch failure/leak would be preferable in the rear circuit rather than the front.
The residual pressure valves do not affect the pressure switch, which it is actually quite in-sensitive; I really have to stomp on the pedal for the brake light to come on; partially because it is on the rear circuit. But a quick dab on the pedal doesn't do it. I agree with zetec7, that a lightly operated switch would be helpful if one wants to use the brake as a warning function. I don't drive in any traffic to speak of, but I have thought about this issue.
Over the winter I will re-visit this. I'm thinking of incorporating a motorcycle rear brake switch and possibly a small lever or push rod attached to the pedal. No drilling in the arm, but a small hole in the pad area will have no effect on the pedal strength.

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 Post subject: Re: Brake Light Switch
PostPosted: August 15, 2016, 2:47 pm 
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Joined: May 1, 2012, 9:43 am
Posts: 336
Location: Sidney, BC, Canada
I don't think the lack of return spring on the wilwood pedal assembly is a problem. I'm presuming that the master cyclinders return all the way to the extended position each time, right? I think they would have to in order to allow fluid to flow from the reservoir. Looking at pictures of the wilwood assemblies, it looks like on the floor mounted models you can have a switch mounted on the floor, pointing up at 45 degree (ish) angle towards the bottom of the pedal just above the pivot point.

Btw, if you run two pressure switches, wire them in parallel to your brake light relay. That way if either or both of the switches are closed, your relay will be engaged.


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 Post subject: Re: Brake Light Switch
PostPosted: August 15, 2016, 7:08 pm 
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Joined: November 13, 2009, 9:31 pm
Posts: 138
Location: Connecticut
Quote:
You can get some very small SPST-NO (Single pole, single throw, normally on) pushbutton switches that you can integrate into your upper travel stop for your pedal (whatever part you have to keep the pedal from flopping back). These typically won't handle full brake light current so you just run them to a relay. With the normally-on buttons, pushing the button will turn the open the circuit, and the button is positioned so it is pushed when the pedal is up.

One example of such a button:
http://www.digikey.ca/product-detail/en ... -ND/529502

In the US NO means Normally Open, NC is Normally Closed, so what you describe would be listed as an NC switch.

Sorry but no good ideas on how to mount one on that pedal assembly though.

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 Post subject: Re: Brake Light Switch
PostPosted: August 15, 2016, 7:26 pm 
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Joined: August 27, 2005, 1:04 am
Posts: 1414
Location: Kamloops, BC, Canada
The switch in your original post, was it spring loaded so that when you push the arm against the spring it would turn the brake lights off? If so, could you mount it to the floor beside the brake pedal so that when you take your foot off the brake one end of the balance bar hits the arm and turns the brake lights off? Might need to find a switch with an adjustable arm position to make it work, but if that were the case, maybe you could even mount the switch ahead of the pedal pivots and keep it out of the way of your feet. Or maybe you could put a small tab on one of the pushrods to actuate the switch too.
Kristian

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 Post subject: Re: Brake Light Switch
PostPosted: August 16, 2016, 7:31 am 
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Joined: February 28, 2009, 11:09 pm
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Location: Connersville, Indiana
Had a wild thought come to mind. How about mounting a mechanical switch through the pedal, so your foot contacts it? As far as current draw, go with LED lights. Very low current draw, very bright lights. Mean combination and no need for a relay!

Bill


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 Post subject: Re: Brake Light Switch
PostPosted: August 16, 2016, 10:13 am 
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Joined: May 1, 2012, 9:43 am
Posts: 336
Location: Sidney, BC, Canada
duratec7 wrote:
In the US NO means Normally Open, NC is Normally Closed, so what you describe would be listed as an NC switch.Sorry but no good ideas on how to mount one on that pedal assembly though.

Oops, you're right, that's what I get for posting in a hurry. I just filtered the digikey buttons by function for Off-Mom, but apparatnely that doesn't mean momentary off, it means off and momentary on. :oops:
Anyway, same switch with opposite function:
http://www.digikey.ca/product-detail/en ... -ND/525746


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 Post subject: Re: Brake Light Switch
PostPosted: August 17, 2016, 12:52 pm 
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Joined: August 2, 2009, 3:34 pm
Posts: 896
Location: Alberta
I wrote to Tilton:

"Do you/Tilton have any ideas for mounting a mechanical brake light switch? Not so much the switch is causing the issue, but how to mount it.

I’d prefer not to use an in-line pressure switch due to reliability, sensitivity, the wiring associated with two switches (one for each system in case of failure), etc. This is relatively easy with an overhung assembly, but I’m having issues with the floor mount while making it look good, simple, and not some switch under the car on the knuckle of the pedal.

You guys sell a switch or have remedied this problem before? Based off my internet search, there seems to be a market out there if you had a solution…."

Their response:

"Our pedal assemblies have no provided provisions for a mechanical brake light switch. The way we have seen it done for many years is to add a hydraulic switch inline to either front rear or both. That does not mean you cannot create a bracket to add a mechanical switch to the assembly just make sure it does not detract from the structural integrity of the unit."

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 Post subject: Re: Brake Light Switch
PostPosted: August 17, 2016, 1:08 pm 
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Joined: May 27, 2006, 9:46 pm
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Location: BC, Canada. eh?
As Dirty Harry used to say, "Marvelous!" Pretty much the same thing from Wilwood - "Yeah, well...good luck with that!"

Oh well, looks like I'm going with a hydraulic switch after all (*sigh*).

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 Post subject: Re: Brake Light Switch
PostPosted: August 25, 2016, 3:38 pm 
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Joined: August 2, 2009, 3:34 pm
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Location: Alberta
zetec7 wrote:
As Dirty Harry used to say, "Marvelous!" Pretty much the same thing from Wilwood - "Yeah, well...good luck with that!"

Oh well, looks like I'm going with a hydraulic switch after all (*sigh*).


I'm going a different direction, but spring switches are available for less than $3.00 which should work pretty slick. Just drill a small hole in the back of pedal/pedal arm, when the pedal is pushed, it releases tension on the spring, closing the switch, when the pedal is released, pulls the spring and opens the switch. Easy peasy, minus the relay which will likely be required, but I'm not here to talk about that.

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