A different way to hook up 911 e-brakes, Another way to do the 911 parkbrake -merged threads Options

[Wes V]

I think I've come up with a totaly new way to hook up 911 parking brakes. It involves making up longer hybrid cables.

It's not complex, doesn't cost tons, and is about as straight forward as possible.

It functions exactly as intended in the 911.

Here is a teaser photo;

(IMG:http://www.performanceforum.com/wesvann/914a/my-rear-brake/b-mrb1.jpg)

Here is a link to my write-up on how I did it (it's a preliminary write-up).

hybrid cables

Wes

(can somebody please find me the photo that I've seen on this site where somebody used a cable end block at the parking brake lever that had set screws)

[okieflyr]

Sweeeeet! (IMG:style_emoticons/default/popcorn[1].gif)

[Wilhelm]

Nice write up.
What are your ideas for the parking brake handle end of the cable?
Have you run across a source of cable ends and sheathing do your own custom cables?
Are new ends generally crimped on or silver soldered?

[LarryR]

Very nice! I am getting ready to to the 911 brake swap with 911 ebrake and have been thinking a lot about the cables.

Larry

[Wilhelm]

Nice write up.
What are your ideas for the parking brake handle end of the cable?
Have you run across a source of cable ends and sheathing do your own custom cables?
Are new ends generally crimped on or silver soldered?

So I'll reply to myself!!!!!!
After some web searching, looking especially at "dune buggy" companies, I'm finding all sorts of bits to shorten and put custom ends on cable. If possible I would like to make seamless cables brake-to-handle with the appropriate ends for my specific application.

[PRS914-6]

Nice write up. Most of us have thought of the idea but didn't care for the angle that the cable attaches to the e-brake because of the shape of the arm. You can't get a straight pull which has a tendency to pull the linkage.

The advantage of the bellcrank version is that you get to use the OEM cables and get a straight pull on the e-brake mechanism by offsetting the arm. Here is a pic

[Larry.Hubby]

Clever and resourceful, Wes. Looks good!

Larry

[PRS914-6]

Another thought on your idea........I don't have an arm here to look at but is there enough room to cut the arm (notch it) and weld a tube in its place with a straight shot to the mechanism? Also, I'm not sure but I'll look the next time my car is on the rack but there might be header interference with the cable out away from the arm...it's very close on a 6. Might need a tight 90 deg there.

You can draw a sketch of exactly what you want and send it to Terry cable and they will manufacture the cable perfectly as you like.

[Wes V]

The issue with the bell-crank solution is that it only "pulls" on one of the speaders. I'm calling it an "issue" and not a "problem" due to the fact that several people have had good results with doing it this way.

As for anchorage of the cable at the parking brake lever, I'm going to work up something using set-screws. It's kind of a no-brainer and I'm not worried about it.

All of the end fittings I've seen in automotive installations are swedged (crimped) on.

Terrycable will do custom cables (according to Otto's in Santa Monica), but they are pricey.

Wes

[Wilhelm]

The issue with the bell-crank solution is that it only "pulls" on one of the speaders. I'm calling it an "issue" and not a "problem" due to the fact that several people have had good results with doing it this way.

As for anchorage of the cable at the parking brake lever, I'm going to work up something using set-screws. It's kind of a no-brainer and I'm not worried about it.

All of the end fittings I've seen in automotive installations are swedged (crimped) on.

Terrycable will do custom cables (according to Otto's in Santa Monica), but they are pricey.

Wes

The 928,944, 924 mechanism requires only a pull, not compression of the spreader, and thus may be more suitable for the bellcrank crowd. The 928 shoes are the same size as the 944 and 911 and instead of having rivets for the spreaders to push on, have notches for the mechanism to lever on much like the brake shoes of american cars. The spreader is part 20 in this pic.

[jj83118]

I was going to post my 911 e-brake cable solution, but I didn't get around to it until now.

I used two clutch cables and modified stock e-brake cable housings. I cut the pedal-end of the clutch cable off and shortened the threaded end a bit. Then I used a cut-off wheel to carefully remove the slotted ends of the stock e-brake cables off. If you make two long cuts 180 degrees apart, you can pry the crimped ends off for use later.

I used a short section of tubing that allowed a tight fit on the stock cable housings outer diameter and spot welded a short section of smaller tubing inside as a stop. This part plays double duty as a mount (all you need is to drill and tap a hole in the trailing arm).

I cut the housings to length first, then slid the clutch cables in to find the right length. After that, it is just a simple matter of re-crimping the ends on the cables and welding them (weld only on the crimped part into the cable).

I hope this all makes sense...I am including photos that better describe the process.

[jj83118]

Another shot from the inside.

[jj83118]

Welded cable end.

[jj83118]

A complete cable (still need to shorten the threaded end).

[Wilhelm]

Welded cable end.

So when you cut this cable end, did you essentially split the tube and pull the old cable out? I take it you welded the cuts back together to remake a tube and then crimped this tube shut. Is Crimping always best? Does silver soldering the end onto the cable embrittle the end of the cable. I seem to remember 30 years ago a well driller reattaching his drillbit ends on 1" steel cable by brazing.

[sixnotfour]

Does silver soldering the end onto the cable embrittle the end of the cable. I seem to remember 30 years ago a well driller reattaching his drillbit ends on 1" steel cable by brazing.

silver solder the way to go but crimping is way more effective.
never have tried the mig weld.

[Wes V]

Welded cable end.

I like this!

I never thought it would be possible to remove and replace the end fitting.

What type of welder did you use? (mig or tig)

Wes

(dang photo isn't coming up)

[ClayPerrine]

This thread made me want to post this now. The problem I see (from experience) is the way the cable is routed in the other thread, you are going to melt it against the heat exchanger/header. It is just too close!!!


I came up with a different way to do the 911 park brake, using the stock 914 park brake cables.

First, buy some 1" conduit, and a conduit bender. Then bend the conduit until you have a 90 to 100 degree bend with a nice, gentle radius.


Weld the washer from the inboard end of the 911 park brake setup onto the end of the bent conduit. Drill a 1/8 inch hole in the outside of the tube, right at the end where the washer is welded. On the other end, cut 3 slots parallel with the end of the tube 1/16 inch from the end.






Take the 911 park brake cables that you got with the brakes, and cut them off. Pull out the inside, and make sure that you leave the cable long enough that it will reach the end of the tube when the threaded end is pushed through the hole in the washer. Braise up the cable end that was cut to keep it from fraying.


You can see the cutoff 911 park brake cable and the tubing in the background.

Then go to the hardware store and buy a couple of barrel nuts used for lawn mower cables. Measure the amount the rear end of the 914 park brake cable sticks out when it is disconnected from the handle and pulled all the way rearward. Drill out the clevis on the end of the 914 park brake cable so the barrel nut will go through it.

Put the barrel nut into the clevis on the end of the 914 park brake cable. Slip the braised end of the 911 park brake cable into the barrel nut. Tighten the barrel nut, then grind the barrel nut flush with the side of the clevis. Trim off the excess cable until you can make a straight cable out of the two joined cables.





Put the now extended 914 park brake cable into the tube, and using the 1.8 inch hole in the side, push it through until you can pull the end out the center of the washer.

Put an E clip into the slots cut in the tube to hold it to the 914 park brake cable. Hook it up to the 911 park brakes on the back, and the handle on the front. Make sure the adjustment nuts are all the way back when you put the cables into the chassis on the handle ends.

Take the end of the tube and support it where the original park brake cable end goes using a 6x.10 bolt, 2 6mm fender washers, and a padded cable clamp. This allows the cable to flex to the side when you pull the park brake.






You can see from the pictures that the cables never come near the heat exchangers, and the park brake works great on my car!

Adjustment:

Adjust the shoes per the 911 service manual. When your shoes are adjusted correctly, then use the adjustment nuts on the cables to adjust the handle height when the brake is pulled.



I can take additional pictures of the brake setup, or you can see it in person at the Rocket City Ramble. Bring your Cameras!

[Wes V]

Clay;

The fact that what I did would place the sheathing close to the heat exchanger is a very valid consern!! My car is an on-going project and I don't know if it will be a problem at a latter date or not. (I'm planning an engine swap)

Most of the time that I post stuff, it's to get an idea out there. It seems to have worked due to a bunch of methods being brought up.

(I did think of making up the length of 1/2" stainless steel tube with a 90 degree bend, however the bender I have would have put too tight of a radius bend on it for what I was comfortable with)

Wes Vann

[ClayPerrine]

Clay;

I'd have prefered that you just post this after the string I did. I'm not going to be offended.

The fact that what I did would place the sheathing close to the heat exchanger is a very valid consern!! My car is an on-going project and I don't know if it will be a problem at a latter date or not. (I'm planning an engine swap)

Most of the time that I post stuff, it's to get an idea out there. It seems to have worked due to a bunch of methods being brought up.

(I did think of making up the length of 1/2" stainless steel tube with a 90 degree bend, however the bender I have would have put too tight of a radius bend on it for what I was comfortable with)

Wes Vann

Ok.. I didn't want to hijack your thread. I can merge them for us.

My method is cheap, probably around 50 bucks all told.

I had a 911 park brake in my car since I got it running 3 years ago. I used custom cables at first, and I melted one on the heat exchanger. That is why I came up with this method. You, being a machinist, could probably do it better, but it works.

I know from looking at the cable radius yours is going to contact the heat exchanger/headers.

I need a stop for mine like you put in.