what is the minimum thinkness for brake discs

wijcc · 22 Oct 2009 at 12:53

Does anyone know what the minimum thinkness for brake dics on a ford focus is, and how can you tell if the minimum thinkness has been reached and the discs need replacing?
Thanks in advance guys

Clarkey · 22 Oct 2009 at 13:16

Which model and year or Focus?

wijcc · 22 Oct 2009 at 13:24

2001 1.6 Ghia (mark one), thanks.. front disc and rear drum brakes by the way

Clarkey · 22 Oct 2009 at 13:27

20mm min thickness.

wijcc · 22 Oct 2009 at 14:14

thanks, a stupid question but how and where do you measure this from?

Barry Smalley · 22 Oct 2009 at 16:10

thinkness????

Barry Smalley · 22 Oct 2009 at 16:12

wijcc said:
thanks, a stupid question but how and where do you measure this from?

across the faces of the disc. use a vernier caliper for ease and accuracy.

Gaygle · 22 Oct 2009 at 16:13

wijcc said:
thanks, a stupid question but how and where do you measure this from?

Usually use a caliper measuring thing (technical term)

Barry Smalley · 22 Oct 2009 at 16:19

Gaygle said:
Usually use a caliper measuring thing (technical term)

whats that then? like a caliper with a preset gap?

fornowagain · 22 Oct 2009 at 16:22

Vernier is no good, it'll measure the unworn width if you're not careful. Cheapo Micrometer is best.

Barry Smalley · 22 Oct 2009 at 16:26

although not quite as accurate, the standard (non-digital) vernier is far easier to use with just one hand.

Barry Smalley · 22 Oct 2009 at 16:27

Barry Smalley · 22 Oct 2009 at 16:29

to be honest, if we really are talking about measuring to that sort of accuracy, you are probably better changing the discs anyway.

Dogbreath · 22 Oct 2009 at 17:00

fornowagain said:
Vernier is no good, it'll measure the unworn width if you're not careful. Cheapo Micrometer is best.

This. It's difficult (but not impossible) to use a vernier if the disk has a lip on the outside.

wijcc · 22 Oct 2009 at 17:34

cool, thanks

danza · 22 Oct 2009 at 17:38

Cheapo micrometer for sure, and not a caliper for reasons already stated.

loltim · 22 Oct 2009 at 17:57

Barry Smalley said:
thinkness????

I normally just ignore bad grammar, but 3 times in the same post? lol..

fornowagain · 22 Oct 2009 at 20:48

Barry Smalley said:
although not quite as accurate, the standard (non-digital) vernier is far easier to use with just one hand.

You can use a slip gauge on either side of the disk with a vernier to avoid the lip, but its a pita. A 0-25 mic can be had for about £6.

Jonnycoupe · 23 Oct 2009 at 01:05

fornowagain said:
Vernier is no good, it'll measure the unworn width if you're not careful. Cheapo Micrometer is best.

Measure the lip aswell then and take that from the total thickness

BigglesPiP · 23 Oct 2009 at 01:17

Barry Smalley said:

So you can tell how thick the ridge is?

You need a micrometer screw gauge.

Or, replace disks with every pads, not that expensive, greater heat dissipation/capacity.