DIY: Rebuild Snapped Handbrake Cable [FOR CHEAP!]

[daktah]

As these cars age and handbrake cables snap and are thrown away, handbrake assemblies will become more expensive, but more importantly harder to find. When my cable snapped I didn't want to spend $150-200 on a used one with who knows how much life left in it (if I could even find one), so I decided to try and refurbish mine to not only save money, but also fix it permanently to not have to deal with it failing ever again. But failing that, at the very least make it cheap and easy to continuously rebuild.

DISCLAIMER:
While this project is quite straightforward, I have not done any long term
testing (I just finished my experimentation, built a cable and reinstalled the
handbrake yesterday afternoon) so understand that there is a possibility, no
matter how slight, that your new cable could easily fail again, or cause damage to
the rear cable bracket. Also, I've already identified improvements and
alternatives that could provide better results than the process I went with, so
make sure to read the notes at the end.

Parts List:

• Jacketed steel cable (5/32" OD, 1/8" core)
• Steel ball bearings (10mm diameter, stainless recommended)
• Aluminum rope stops (1/8" ID)

Tools List, Required:

• 1/8" drill bits (high quality cobalt, M42, etc for steel highly recommended)
• Angle grinder or bench grinder
• Bench vise
• Hand drill
• Metal file (any shape)
• Philips and flathead screwdrivers
• Pliers
• Propane/MAPP torch (not needed with unhardened ball bearings)
• Ruler or tape measure
• Steel cable cutter/snipper (or grinder+cutoff wheel)
• Utility knife

Tools List, Recommended:

• Center punch (especially if drilling by hand)
• Digital calipers
• Drill press, lathe or milling machine
• Hydraulic crimping tool
• Spotting drills or center drills

Steps:

1. It's best to get the hard part out of the way first (pun intended).
   If you bought hardened ball bearings (if you don't know for sure, then you did), they will need to be annealed first as they are far too hard to be able to drill through. You will need some steel scrap or a brick or something that is heat resistant, fireproof and safe to torch your ball bearing on. I happened to have had a small steel plate with a chamfered hole which was perfect. It really doesn't matter exactly what you use, just so long as it works.
   You will want to heat the bearing to a glowing orange, hold it for a minute or two, and then let it SLOWLY AIR COOL. If you drop it in water, you will just reharden it and you will have done nothing but waste your time. Be patient and give it plenty of time to cool before you touch it.
   
   
   
2. Once safe to touch, use your grinder to grind a small flat into the bearing. If you have a mill or lathe, you can machine a flat. Once done, put it in your vice and center punch the flat, then use your spotting/center drill to make a pilot divot. Finally, drill that hole all the way through as straight as humanly possible. Obviously this far easier if using a machine rather than hand drilling.
   If you bought stainless bearings, the name of the game is high feed pressure, constantly pulling out to clear chips, and do NOT let the drill bit rub and squeal. If you rub too much and build too much heat, the metal will work harden and will wipe out your drill bit and require annealing again to soften it. A sharp high quality bit makes this much easier.
   
   
3. Once the bearing is take care of, you can open the handbrake and remove the old cable. I wont go into the process of actually removing the handbrake from the car as it is pretty simple and there are plenty of guides around the internet.
   Once you have your handbrake out of the car you first remove the contact plunger assembly with your philips screwdriver, pry up the tab closest to the part number and date of manufacture stamping (ignore that I did all 3 in the picture) with your flathead, then pry up the plate to expose the crimp that holds the cable in. You only need to pry the plate enough to be able to remove the cable stop, then you can pull out the cable.
   
   
   
4. To make the cable, you will want to cut off a length that is about 15.5 inches. On one end, strip the jacket a bit more than 8mm (a little less than 11/32"), put on a ferrule, then crimp it. If using a hydraulic crimper, I've found that first using the "25" dies, rotating 90° and crimping again, then the "16" and finally again at 90° provides a very tight crimp on the cable while also coincidentally making it the perfect width to fit into the retention slot (about 1/4 x 1/4") in the handbrake with very little filing required, albeit too long and requiring it be ground down some (about 7/16").
   If using a bench vise, you just have to keep pressing back and fourth to keep it square and producing a good crimp, and it will probably require a fair bit of filing to size it.
   As you can see in the picture, using a hydraulic crimper produces a much tighter and uniform crimp over the cable, making it far stronger.
   
   
   
5. Once the crimped ferrule fits, route the cable though the handbrake and through the metal tail, then use your pliers to bend the tab back over on the plate. The way I did it was by bending the plate as flat as possible, using one set of pliers to hold it down the rest of the way, and then a second set to fold over the tab, which could then be flattened all the way. You don't have to worry too much about getting the plate perfectly flat again, getting it good enough is more than sufficient.
   
   
   
6. Strip the other end of the cable about 17.75mm (a bit under 3/4"), add the ball bearing first, and then the ferrule. Crimp the ferrule as before. Don't strip it before running it through the tail or you're gonna have a hell of a time getting it though without it fraying, and make sure you dont crimp it without the tail installed first otherwise good luck getting the tail on over it lol.
   
   
   
7. Once crimped, the ferrule will have to be shortened and beveled to be able to fit into the rear cable bracket. I forgot to measure it, but it appears it is about 10mm or 3/8"ish. It should fit though the hole with little to no force required.
   
   
   
8. You are done! All that is needed is to reinstall the handbrake (don't forget to screw the contact plunger back on) and hook it up to the rear cable bracket. Note that you may need to remove the cable ends from the brake levers on the wheels to get a bit more length to reach the cable end (they unlatch easily after pulling the cable out of the stopper in the knuckle, no need to remove the wheels or anything), and you may also have to adjust the parking brake adjusters behind the rotors to get it to feel right. Or if you are lucky, it will will just work and that will be that.
   

Notes:
There are a number of things that occurred to me midway or after I was done with this project that could make it better.

1. Because I didn't pay attention, I though the part of the rear cable bracket that the bearing bears on had a hole and a chamfer for it to sit and center in, but it turns it's just flat with a hole only big enough for the cable to pass through. With this being the case, it might be better from a load spreading perspective to grind a much larger flat (or even just make it a hemisphere) into the bearing so it is pulling against the bracket across a (relatively) large flat face rather than a small concentrated point.
   
   
2. In the same vein, it might also be better to use a softer metal like aluminum or brass to prevent possible damage to the bracket (as mentioned in the disclaimer), especially since the factory material is likely some sort of die cast aluminum alloy. I actually probably would have went with aluminum but 3/8" or 10mm balls are hard to find even on Amazon or McMaster, but you can get brass balls in those sizes easily on both, but I didn't think of using brass until afterwards.
   
   
3. To harp on this same point further, McMaster has ball swage fittings that would eliminate the need for a ball bearing entirely. I actually looked at these in the first place, but wrote it off since i thought it would be too small for how i thought the cable plate worked as above (3/8" = 9.5mm). In hindsight, this is probably the way to go. Just note that it would have to be installed backwards (shank towards the end of the cable) as the shank would be much to large to fit through the hole meant for the cable only, and you would likely still have to trim the shank down to actually fit into the cable bracket too. The fact that you would then automatically have a flat face as well as a softer metal bearing against the cable plate would likely make this the superior option for less money and effort.
   
   
4. Finally, it may be possible to just repair your factory cable in place with zero disassembly (besides removing it from the car). If your factory cable just pulls out of the ball end (which seems to be 99% of failures), you may be able to cut off the frayed end, strip the jacket back and put a slightly larger ball swage on the factory cable (it seems to be just a bit bigger than 1/8"). It would also need to be backwards and trimmed to fit, but in theory it should work perfectly fine. The only reservation is that the cable would be much shorter (probably 3/4" to an inch counting what has to be cut off and what is "lost" behind the face of the ball), but if it does indeed work then that would be the undisputed best option in terms of ease and cost, bar none.

[Joe.G]

Nice write up, Thanks