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View Full Version : Brake Parking brake pad angle?



jawn101
05-15-2023, 09:52 PM
So I?ve been rebuilding my parking brake, and got new cables and pads. But I don?t think these
pads have the proper angle on them to grip the discs in the rear. I?ve installed them and spent three days trying to get them to securely hold the weight of the car, and they just won?t.

Do I need to machine them myself? I see lots of blog/forum posts talking about needing to sand material off which is why I bought them from Houston instead of a local parts store; I hope they won?t need that? But if they do, I don?t see any detailed instructions to get the right angle. Anyone know how/where to look?

glockworks21
05-15-2023, 10:34 PM
mine did not work at all when i got the car. i ordered new pads and they were beveled. I dont think i did anything to them. This video helped me get mine set.




https://www.youtube.com/watch?v=Dm9hqdfpqOo

jawn101
05-15-2023, 11:02 PM
mine did not work at all when i got the car. i ordered new pads and they were beveled. I dont think i did anything to them. This video helped me get mine set.




https://www.youtube.com/watch?v=Dm9hqdfpqOo

Yeah, it?s a solid video. But I have definitely mastered the workings of the system and can tell 100% that these parts are just not up to scratch. On inspection with the handbrake fully engaged, only the leading edge of the pad is actually gripping the rotor. I can get 2 index cards between the trailing edge and the disc, so it?s definitely that the pads need to be chamfered. The cable and calipers are properly aligned, though I know that?ll need to be redone once these pads have the right angle.

The question is just how I get that angle on them. I compared the old ones to the new and it?s pretty pronounced. New are totally even and level, old have a couple degrees of tilt.

WHO1DMC
05-15-2023, 11:23 PM
The ones that DMCH sells don't have the beveled surface. The beveled surface is not much.
I don't have any way to measure the angle but I hope this will help. The right side of the pad in the picture is 2mm thinner than the left. This is a brand new ferodo brake pad.
I think sandpaper would work just fine.

Dave B.https://uploads.tapatalk-cdn.com/20230516/db365dd6ffbc5142bd70c8320b61033a.jpg

Sent from my SM-G991U1 using Tapatalk

jawn101
05-15-2023, 11:32 PM
The ones that DMCH sells don't have the beveled surface. The beveled surface is not much.
I don't have any way to measure the angle but I hope this will help. The right side of the pad in the picture is 2mm thinner than the left. This is a brand new ferodo brake pad.
I think sandpaper would work just fine.

Dave B.https://uploads.tapatalk-cdn.com/20230516/db365dd6ffbc5142bd70c8320b61033a.jpg

Sent from my SM-G991U1 using Tapatalk

Thanks so much Dave! I have my old pads (well, 3 of them. One dismantled itself and fell out somewhere) to compare to and I can see the angle is pretty prominent. I just don?t know how to get an angle on my new ones. I don?t have a belt sander or anything, but maybe I could get ahold of one somewhere.

82DMC12
05-16-2023, 03:49 PM
The ones that DMCH sells don't have the beveled surface. The beveled surface is not much.
I don't have any way to measure the angle but I hope this will help. The right side of the pad in the picture is 2mm thinner than the left. This is a brand new ferodo brake pad.
I think sandpaper would work just fine.

Dave B.https://uploads.tapatalk-cdn.com/20230516/db365dd6ffbc5142bd70c8320b61033a.jpg

Sent from my SM-G991U1 using TapatalkWhere does one get the Ferodo pads?

Sent from my Pixel 6a using Tapatalk

jawn101
05-16-2023, 03:53 PM
Where does one get the Ferodo pads?

Sent from my Pixel 6a using Tapatalk

Go sells them, but they're very expensive ($80 vs $15)

I spoke with Arran earlier and he gave me a great suggestion - to disconnect the brake cable from the caliper, remove the return claw, and stick 80 grit adhesive disks to the brake rotor surface. Then you can squeeze the caliper by hand and rotate the rotor back and forth to shape the pad correctly.

I'm gonna give this a try, and if it fails, well - it's a quick cleanup and I'll buy the Ferodo pads for a small fortune just to be done with this goofy job.

Interestingly, I emailed with Houston earlier about this as well and they claim they never shape these pads when they install them on customer cars. Which sorta makes me wonder what their standard for "working" on the handbrake is - it doesn't seem optional to me.

jawn101
05-16-2023, 10:01 PM
Well, now I'm really frustrated.

I did Arran's procedure to shape the pads, which worked great BTW. I've attached some pics of what it looks like.

I then recalibrated both cables and both adjustment screws. The wheels spin freely with the brake off, the handle pulls up 4-5 clicks in total, and both calipers actuate and grip the wheel so tightly you'd need a bulldozer to push the car on a flat surface. All seems great.

But, my litmus test is putting the car on my (pretty gentle, approx 5 degree) inclined driveway. Transmission in neutral, parking brake on, service brakes off - it rolls right back.

I also confirmed on a straight flat road with the transmission in neutral that the e-brake will stop the car eventually from about 10mph.

I don't think I can realistically apply any more force here. What am I missing?

***Shaping brake pads***

69668
Remove the service brake pads to avoid fouling them

69672
69669
Remove the parking brake caliper by removing the cable from the arm, backing the adjustment screw most of the way out but not so much that it loses thread on the inner ratchet, then unlocking the lock tabs, removing the two pivot bolts and the return paw

69670
Cut up some adhesive very coarse grit sanding material

69671
Stick it to the brake rotor, on both sides in the same spot

69673
Put the parking brake caliper back in place, but without the return paw, cable, or lock tabs. You also needn't screw in the pivot bolts, they can just float for now.

Squeeze the two halves of the caliper together with one hand and rotate the rotor back and forth with the other. The abrasive will very quickly cut down the parking brake pad to just the right shape.

When that's done and you can confirm the pad contacts the rotor evenly, take the parking brake caliper back off. Remove the adhesive from your brake rotor, being sure to get all traces of it off the surface. Reinstall the caliper properly, and put your service brake pads back in place.

WHO1DMC
05-16-2023, 11:18 PM
I've tried doing some research on bedding in parking/handbrake pads. There really is not a lot on this subject but they say they work better if you do. The little I found say to apply the handbrake at a max speed of 20 mph. They get the vehicle up to 20 mph let off then start applying the brake until they almost come to a complete stop or a complete stop. They do this a handful of times with a little time in-between you don't want them to get really warm.




This is just a thought. You can always do your own research.
Dave B.

jawn101
05-16-2023, 11:27 PM
I've tried doing some research on bedding in parking/handbrake pads. There really is not a lot on this subject but they say they work better if you do. The little I found say to apply the handbrake at a max speed of 20 mph. They get the vehicle up to 20 mph let off then start applying the brake until they almost come to a complete stop or a complete stop. They do this a handful of times with a little time in-between you don't want them to get really warm.




This is just a thought. You can always do your own research.
Dave B.

Yeah, this was exactly what I was thinking with my moving test - I didn't go quite to 20 but I could for sure. I have had to bed in tons of hydraulic MTB brake pads and it was in my head.