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Wed Mar 14, 2007 4:46 pm

I do not know to much about cutting brakes, but i am wondering if it would be possible to split the ebrake cables apart, make two handles, and through the use of a pivot point on the handles, make cutting brakes. Will this work?

Wed Mar 14, 2007 5:37 pm

I had considered the same thing on a previous car. In theory it should work fine. It may however cause a strange wear on the brake shoes as the part of them that is used for the Ebrake doesnt usualy wear down since the ebrake is only used to hold the brake on = not much wear. you will need to keep an eye on the adjustment of the shoes.

Wed Mar 14, 2007 5:49 pm

Funny you should ask. I have just finished my plans (mentally) on a way to utilize the stock setup.
When you remove the boot you see the little piece that each cable passes through and cables held in place with nuts? All you have to do is (at least on my '67) is to weld a permanent cross piece there and devise a way to slide the cables out of a notch in the end of that piece. It's not quite that simple as you will have to provide some tension on the disconnected cable so it doesn't slip from the track on the bottom while you are using the other brake for turning/getting un-stuck. This can be accomplished by having a separate lever hinged left to right with a slight preload for each cable.
Now for the operation just slide one of the cables from the welded cross piece (the left one out of position if you need to turn right) and use the emergency brake handle making sure to keep the button depressed at all times.
If you look closely at the stock e-brake you will see that the pivot pin that keeps it together is also the fulcrum point so you must use the stock handle. If you try to rig separate handles for turning you will have too much friction for decent operation. I still haven't figured how to modify the stock boot.
I think this will suffice for the occasional user without having to install a hydraulic turning brake. One advantage of this besides low cost is you still have your functional e-brake.
Feel free to expound on this idea.
Marvin

Wed Mar 14, 2007 5:58 pm

I'm not sure what your driving but it may be possible to widen the ebrake mount and have two handles side by side and just weld the top plate that holds the cable (stock is loose and relies on both cables to hold it). If you want to get real fancy try getting two 80lb pull electric solenoids (power door lock ones) and wire seperate switches, maybe even adjust pressure using a dimmer switch. can you tell I'm an electrician? :idea:

Wed Mar 14, 2007 6:18 pm

Dirtybug, Good idea but you can't just pull on the cables. You must have leverage and that is provided for in the stock setup with the rounded part that moves with the handle located just beneath the fulcrum point.
You can replace the stock handle with two separate handles but then you would have to devise a lock if they were to be used as emergency brakes.
Hmmmmm Just thinking out loud but there may be a way to modify the stock handle to accommodate the 80# pull solenoids and still use the clicker to lock the e-brake. How big (bulky) are 80# pulls?
Marvin

After reading this over I see a problen unless you could feather the turning brake with some sort of variable resister mounted on the handle.

Wed Mar 14, 2007 6:21 pm

yeah, it makes sense that it should cause wear, but i think it would be minimal. i will be using this on a sandrail, so i plan on making a new mount and 2 seperate handles. i was thinking i would mount the cable below the pivot point.

Marvin, i like your idea, but it doesnt make sense for me to do it that way since i will be making a whole new mount. It seems like you put a lot of thought into it. good luck if you decide to try it.

Wed Mar 14, 2007 6:27 pm

yeah, i am trying to figure out a way to devise a lock with 2 seperate handles. not too sure yet. I like the electric soleniods idea, i might even try it! I am not much of an artist, but this is the basics of what i was thinking of making, just to give you an idea. the black line towards the bottom of the handle would be the cable.

Wed Mar 14, 2007 6:30 pm

scaglietti540, I didn't realize you were needing it for a rail. By all means devise a two handle setup. It should be easy to rig at least one of them
for an lockable e-brake if needed.
Marvin

I just saw your drawing. Make sure you calculate your measurements so you can use stock, easily obtainable cables.

Wed Mar 14, 2007 6:55 pm

scaglietti540 wrote: I do not know to much about cutting brakes, but i am wondering if it would be possible to split the ebrake cables apart, make two handles, and through the use of a pivot point on the handles, make cutting brakes. Will this work? It will work but drum brakes don't work very well when used as cutting brakes, compared to discs. Back in the 70s or 80s there was a kit to do just what you are describing.

Thu Mar 15, 2007 2:04 am

Johnny's Speed and Chrome used to sell them for about $12- a couple of flat chromed straps with a nut welded at the bottom for the cable, and a tricycle rubber grip at the top. They mounted on the stock pivot.
Better than nothing. Good enough to get you out of a mudhole.

Thu Mar 15, 2007 3:08 am

GA_Boy Dirtybug, Good idea but you can't just pull on the cables. You must have leverage and that is provided for in the stock setup with the rounded part that moves with the handle located just beneath the fulcrum point.

the pull solenoids wouldnt need a fulcrum for leverage if you had them pull the lines straight. the ebrake handle needs the leverage so you dont have to use much force.

Thu Mar 15, 2007 8:56 am

I was thinking the same thing.

except mounting a pulley forward of the handle, then run the other side throught the pulley and back to the other brake.

I dont know how well it would work, but I was hoping to get a push pull type of brake. Push for left, pull for right.

sorry I had to bastardize your picutre

Thu Mar 15, 2007 9:16 am

I dont think the push pull set up would work with cables. You would have to leave too much slack in one side to be able to pull the other, but then the side with the slack wouldnt pull the brakes because there is too much cable. I think the only way to do single handle turning brakes is with a hydrolic set up.

If I am wrong in my thinking, please correct me.

Thu Mar 15, 2007 10:59 am

I didnt think slack would be a problem.

But if youve got one pulley why not add two more nearer the brakes and use springs.

Brake cable tensioners. Im going to have to copyright that.

Thu Mar 15, 2007 2:58 pm

My father fabricated cutting brakes on the manx he built in '68. It was nothing more than two handles on a pivot mounted to the e-brake. The cables were set so you had to pull the e-brake up 2-3" and then you could grab the left/right side and push the cutter handle down. (these were angled up about 30 degrees above the e-brake handle) Very simple setup, and you don't need a lot of cable movement.

I don't have any pics, and the manx was sold ~20 years ago... I could probably draw something up...

it was effective, and could be operated one-handed... one option was to hold the release button, squeeze the left or right cutter to the e-brake handle and pull the handle up... or you could pre-load the e-brake a bit, and push down on the left/right lever for those "squirrelly" spots.

The levers came up about even with the e-brake handle, and the pivot was quite close to the cable, but I don't have exact measurements. The whole setup was fabricated from a piece of pipe welded to a piece of angle-steel (for each side). Pivot was a 1/4" bolt w/ hole drilled through the e-brake handle and the angle. Cable ends were unchanged, and with the cutter in the full-up position, the e-brake functioned normally.

The best way is to use the typical neal/CNC hydraulic cutting brakes, but this worked for ~20 years for us.

Hope this helps...

-John

Thu Mar 15, 2007 3:47 pm

I think the push-pull setup is a good idea, but i would rather have 2 handles. I know that with drum brakes, a cutting brake wont be effective, but i figure that it would still be better than none.
JohnSawyer-i would definitly be interested in a drawing if you dont mind. Was the ebrake still ususable?

Thu Mar 15, 2007 3:58 pm

The e-brake was fully functional. The trick to setting this up correctly is to get the right amount of leverage and cable movement to apply the brakes...

Without the original buggy, it may become an issue of trial-and-error to get something that works well... If I remember correctly, there were two holes in the angle where the cables were moved once to increase the cable throw...

I'll see what I can come up with...

Fri Mar 16, 2007 2:35 pm

here's a crummy drawing:

The top hole is for the e-brake cable, the side hole is the pivot. Please note that the distance between the top and side holes determines the distance the cable is pulled and how much force is applied...

You'd need one for the left, and one right...

I haven't thought about this design in 20+ years (in fact the first time I saw one without a cutter-brake I thought it was missing parts... I drove this buggy from the age of 12 in the desert)

It's possible that the pivot point was lower, and mounted to a tab welded to the e-brake handle... it's been a LONG time since I've seen this...

Fri Mar 16, 2007 4:05 pm

thanks for the drawing. It is definitly helpful. I think that i might keep the ebrake, and just add handles for each individual cable, allowing me to have cutting brakes and an ebrake.

Fri Mar 16, 2007 6:36 pm

if you have a rail using a beetle pan or have a baja ... you can reroute the cables from the e brake to the heater control levers weld a bar under the e brake lever so it reaches under the heater levers so you can have turning brakes or pull the e brake and it will pull both heater levers and lock

also using you e brake for turning brakes does where on the brakes because the cables only work one shoe on each wheel not both but if you have disc brakes it wont