New disc issue

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Ducklakeview
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New disc issue

Post by Ducklakeview » Fri Jan 05, 2018 8:04 pm

Nictrix wrote:
Fri Jan 05, 2018 6:05 pm
VRSteve wrote:
Fri Jan 05, 2018 5:59 pm
Nictrix wrote:
Fri Jan 05, 2018 5:58 pm
:lol:
Happy to be proved wrong.
I really cant see it being wear indicators for a few reasons.
The amount of material taken off the disc to reach that level would be huge.
When the disc wears it never wears at the edges so it would be difficult to see if the disc had reached these marks.
If it was wear marks surely they would have them the same sort of size equally spaced around the disc.

It isn't a wear indicator at all. It IS for balancing the disc after its been machined.

The brake pads don't sweep that near to the edge and therefore even a well worn disc would still have those machined notches intact, so that the balance doesn't change as the disc wears, it assumess that a disc wears evenly, which most do unless there is an issue with pads/calipers. THAT is why they physically stamp the min thickness on the edge, because the pads don't wear the edge..

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Last edited by Ducklakeview on Fri Jan 05, 2018 8:12 pm, edited 1 time in total.

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New disc issue

Post by Beedub » Fri Jan 05, 2018 8:11 pm

you'll also notice that this cut area varis from disc to disc... some have a very large, some tiny, some None... if this was wear related it would be a standard size across the board, it is for balancing purposes, it has ZERO to do with wear, to measure wear, you measure the overall thickness and your given a minimum thickness engraved on the side usually.

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New disc issue

Post by TomK » Fri Jan 05, 2018 8:24 pm

It would also make sense that were any balancing be required to the disk that this removal of metal would be within the confines of the minimum thickness level, which would seem to tally with the measurements made.
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New disc issue

Post by Nictrix » Fri Jan 05, 2018 8:51 pm

buzyg wrote:
Fri Jan 05, 2018 7:11 pm
Nictrix wrote:
Fri Jan 05, 2018 6:49 pm
So whats correct?
A forum post from 4 years ago or a youtube video from 6 years ago.
Not sure I understand the point of your question. :?

However I believe the video is, as it clearly shows how the marks are made. Plus there are other similar video's of brakes being balanced using this method, all over the internet. :wink:
Sorry my question was about whether VRsteve was correct with his idea that the marks were wear markings or Warmasices original thoughts on balancing which I agree with.
VRsteve, at what point do I get an apology either on here or via PM? :)
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New disc issue

Post by Attilio » Fri Jan 05, 2018 8:53 pm

Dual purpose perhaps?

they are for balancing and the width of the cut is chosen to work as a minimum thickness indicator?

everyone would be happy :)
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New disc issue

Post by Lower » Fri Jan 05, 2018 9:07 pm

VRSteve wrote:
Fri Jan 05, 2018 7:57 pm
In my garage I have a set of disks of HRH's mini.

The grove cut in the disk measures 8.4mm, the same as the minimum thickness stamped on the front of the disk.

I measured using a digital calliper, so I am MORE than happy that I'm correct in what I say.
It's not a wear indicator. Discs lip when they wear as the pads are always slightly inset from the edge of the disc so that the pads don't lip.

The balance machining will be the same width as the disc at max wear so that the minimum amount of material can be removed from the disc (i.e. No deep groove which would weaken the disc). If it was any wider than the max allowable wear there would be the risk of the disc balance changing as it wore.
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New disc issue

Post by MrPT » Fri Jan 05, 2018 9:56 pm

Come on, everybody. Big hug time.
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Post by warmasice » Sat Jan 06, 2018 1:01 pm

I'll repeat.. it's for balancing. Nothing more to say.
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Post by mmm-five » Sat Jan 06, 2018 1:09 pm

It’s the angel’s share :poke:
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New disc issue

Post by warmasice » Sat Jan 06, 2018 3:25 pm

mmm-five wrote:
Sat Jan 06, 2018 1:09 pm
It’s the angel’s share :poke:
Or is it the devil's cut? :poke:
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Post by Attilio » Sat Jan 06, 2018 3:45 pm

MrPT wrote:
Fri Jan 05, 2018 9:56 pm
Come on, everybody. Big hug time.
:thumbsup:
Big hug
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New disc issue

Post by BMWZ4MC » Sat Jan 06, 2018 5:33 pm

Nictrix wrote:
Fri Jan 05, 2018 8:51 pm
buzyg wrote:
Fri Jan 05, 2018 7:11 pm
Nictrix wrote:
Fri Jan 05, 2018 6:49 pm
So whats correct?
A forum post from 4 years ago or a youtube video from 6 years ago.
Not sure I understand the point of your question. :?

However I believe the video is, as it clearly shows how the marks are made. Plus there are other similar video's of brakes being balanced using this method, all over the internet. :wink:
Sorry my question was about whether VRsteve was correct with his idea that the marks were wear markings or Warmasices original thoughts on balancing which I agree with.
VRsteve, at what point do I get an apology either on here or via PM? :)
Was an apology offered by PM with the good grace that you publicly offered yours? :|
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New disc issue

Post by Nictrix » Sat Jan 06, 2018 6:02 pm

BMWZ4MC wrote:
Sat Jan 06, 2018 5:33 pm
Nictrix wrote:
Fri Jan 05, 2018 8:51 pm
buzyg wrote:
Fri Jan 05, 2018 7:11 pm

Not sure I understand the point of your question. :?

However I believe the video is, as it clearly shows how the marks are made. Plus there are other similar video's of brakes being balanced using this method, all over the internet. :wink:
Sorry my question was about whether VRsteve was correct with his idea that the marks were wear markings or Warmasices original thoughts on balancing which I agree with.
VRsteve, at what point do I get an apology either on here or via PM? :)
Was an apology offered by PM with the good grace that you publicly offered yours? :|
Its only a bit of banter but no it hasnt been offered. I was only throwing back the line about an apology as it seemed a bit smarmy of VRSteve to demand an apology from me after he assumed he was right and I was wrong after I laughed.
VRSteve obviously thinks that he is correct (he might be although his only defence is another forums post which could also be wrong and that the measurement of the cutouts match the minimum thickness which could be a coincidence) even though it seems most on here think its for balancing.
As Attilio also says, maybe it is for both in which case I was wrong for laughing but also correct.
An apology is not needed. :)
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Post by BMWZ4MC » Sat Jan 06, 2018 6:40 pm

Fair enough. I was curious because you offered a metaphorical handshake and seemed to receive silence in return.
Besides, the cut outs are clearly a cost saving measure by the manufacturer - less metal, less money :P
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New disc issue

Post by MrPT » Sun Jan 07, 2018 2:04 am

BMWZ4MC wrote:
Sat Jan 06, 2018 6:40 pm
Fair enough. I was curious because you offered a metaphorical handshake and seemed to receive silence in return.
Besides, the cut outs are clearly a cost saving measure by the manufacturer - less metal, less money :P
Mine are full of holes too. Bloody tories!
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