Cannon1891
Member
The diameters are machined or ground so the part is rotated in a chuck. It would be very hard, almost impossible to produce the bores on different centres.
Pagid brake discs - a quick heads up. Update!
- Thread starter Roberltd2
- Start date
j3nks79 said:
When diameters are machined at different times to each other of course they can be eccentric to each other.
The OP explained in the opening post that the garage have said the drum diameter is not concentric with the centre of the disc. The shoes are fouling on the inside of the drum.
The rest of the disc could be running perfectly concentric and perpendicular, but the bore for the brake shoes could be eccentric. You would not see the discs moving about. Just the brake shoes fouling inside.
It's an easy measurement for the mechanic.
Attleborough, Norfolk
enuff_zed said:
It is the brake drum bore that is not concentric to the centre to the rest of the brake disc. The brake shoes are fouling on the inside of the drum is what the mechanic has explained.
For the mechanic to make that diagnosis I would hope they measured the discs to make sure. They should know to do that.
If you don't true up a part in a chuck it'll not come off concentric. Things can move and things can be set up wrong.
I’ve watched a few videos now on making brake disks and I’m yet to find any where they machine the braking surfaces. They seem to be left as cast. Maybe I’ve not searched hard enough 
Rockhopper said:I’ve watched a few videos now on making brake disks and I’m yet to find any where they machine the braking surfaces. They seem to be left as cast. Maybe I’ve not searched hard enough
Here's how the Indians do it. :dizzy: :dizzy: :dizzy:
https://youtu.be/Nz1yFR4sa74?si=YWzminx6XALATXrT
I used to work for an engineering firm operating computerised lathes.
I just can't see how this would happen. You'd machine one side, flip it over, then the other side would be machined. All surfaces, both sides, would be run over. When the centre hole would be chamfered on the other side the machine would crash. They don't like crashing.
The overall sizes can vary to a certain percent depending on how often the lathe tips are changed.
You're usually measuring the one you produced whilst watching the next one in production. You have nothing else to do so you may as well.
I just can't see how this would happen. You'd machine one side, flip it over, then the other side would be machined. All surfaces, both sides, would be run over. When the centre hole would be chamfered on the other side the machine would crash. They don't like crashing.
The overall sizes can vary to a certain percent depending on how often the lathe tips are changed.
You're usually measuring the one you produced whilst watching the next one in production. You have nothing else to do so you may as well.
Still waiting for replacement discs. Not been a very good time for the Zed recently, a few weeks ago I had to return a couple of new Vanos solenoids under warranty as they were faulty, then the brake disc saga and, on Monday had a puncture which resulted in a new tyre (the old one only went on last October). They say things come in threes so let's hope it stays that way!
Still, it's nice to be back in the Zed again after spending two days commuting to work on the bus.
I will update on the discs as soon as I can. I hope there is something measurably wrong with them or else I'll be bl**dy fuming :x
Still, it's nice to be back in the Zed again after spending two days commuting to work on the bus.
I will update on the discs as soon as I can. I hope there is something measurably wrong with them or else I'll be bl**dy fuming :x
I’ve had to repair a few broken protection plates that the brake shoe ‘pin’ locks into. When that pops out it throws the brake shoes off and slightly forward.
Equally looking forward to hearing about these Pagids.
OP did you not get them back from the mechanic to return to Halfords
Equally looking forward to hearing about these Pagids.
OP did you not get them back from the mechanic to return to Halfords
The new Brembo discs arrived from Autodoc yesterday afternoon but I couldn’t get them fitted at such short notice. They look the business though, but then again so did the Pagid items when I first set eyes on them.
I think the reason why my mechanic didn’t put the original discs back on was that, not only were they were shot to bits which is why he advised me to replace them but also that the problem with the Pagid discs was to do with the inner (hand) brake drum rather than the disc / caliper set up. So foot brake is good but the hand brake is not.
He had fitted the Pagid discs, taken them off, refitted them and taken them off again before he figured out that the reason the handbrake shoes could not be “bedded in” was because the inner drum was badly engineered.
Local motorfactors were unable to supply compatible discs on the day so he refitted the Pagid discs, but told me to order a new set and not to use the handbrake on anything other than level ground.
So the Pagid discs are still on at the moment but will be taken out Monday or Tuesday all being well.
The Brembo discs are made in China but they do seem to have more info on the box regarding OEM numbers etc. than the Halfords / Pagid discs.
Plus there’s a hologram type thing on the box as well so they must be better.
Right?
Also bought 6X new Delphi ignition coils. They also have holograms on the boxes but more reassuringly have “Made in Portugal” printed on them.
I fitted the Delphi coils on today and they seem to be ok. I even tried to slightly labour the engine at low revs which is when the engine would occasionally seem to miss a beat before. But it’s running nicely now.
Thanks for all the interest in the post.
Robert.
I think the reason why my mechanic didn’t put the original discs back on was that, not only were they were shot to bits which is why he advised me to replace them but also that the problem with the Pagid discs was to do with the inner (hand) brake drum rather than the disc / caliper set up. So foot brake is good but the hand brake is not.
He had fitted the Pagid discs, taken them off, refitted them and taken them off again before he figured out that the reason the handbrake shoes could not be “bedded in” was because the inner drum was badly engineered.
Local motorfactors were unable to supply compatible discs on the day so he refitted the Pagid discs, but told me to order a new set and not to use the handbrake on anything other than level ground.
So the Pagid discs are still on at the moment but will be taken out Monday or Tuesday all being well.
The Brembo discs are made in China but they do seem to have more info on the box regarding OEM numbers etc. than the Halfords / Pagid discs.
Plus there’s a hologram type thing on the box as well so they must be better.
Right?
Also bought 6X new Delphi ignition coils. They also have holograms on the boxes but more reassuringly have “Made in Portugal” printed on them.
I fitted the Delphi coils on today and they seem to be ok. I even tried to slightly labour the engine at low revs which is when the engine would occasionally seem to miss a beat before. But it’s running nicely now.
Thanks for all the interest in the post.
Robert.
North West Surrey
So finally, the Pagid rear discs have been taken off and replaced with Brembo ones and my brakes are fully functioning once again.
As soon as I could, I inspected the discs expecting to see some visible fault in them.
But it was only on closer inspection that I noticed the lip of the brake drum was narrower on one side than on the other. This was the case on both discs.
Disc 1:
Disc 2:
And here’s a photo of both discs where I’ve highlighted the widest and narrowest areas with a black marker to make them stand out more:
Thinking that my mechanic had loosened the adjustment on the handbrake (i.e more travel) to avoid the shoes binding on the Pagid discs, I asked him if he could now readjust them back once the Brembos were fitted. But to my surprise, he told me that he hadn’t made any adjustment to the handbrake at all on fitting the Pagid discs. So not only had they been machined out off centre but it looks like the were bored out to the wrong size as well.
As soon as I could, I inspected the discs expecting to see some visible fault in them.
But it was only on closer inspection that I noticed the lip of the brake drum was narrower on one side than on the other. This was the case on both discs.
Disc 1:
Disc 2:
And here’s a photo of both discs where I’ve highlighted the widest and narrowest areas with a black marker to make them stand out more:
Thinking that my mechanic had loosened the adjustment on the handbrake (i.e more travel) to avoid the shoes binding on the Pagid discs, I asked him if he could now readjust them back once the Brembos were fitted. But to my surprise, he told me that he hadn’t made any adjustment to the handbrake at all on fitting the Pagid discs. So not only had they been machined out off centre but it looks like the were bored out to the wrong size as well.
Got to say Im smelling a rat with your mechanic, shoes always need adjusting with new discs as the tolerance band in manufacture will be quite wide. That dimension you have measured doesnt mean much other than the casting was bored a bit off centre and is not the issue. The dimension that is relevant is the concentricity of the spigot bore to the drum bore nothing else matters. This is best done in a lathe or mounted on a hub backwards and spin it with a dti on the drum bore.
Oh what is clear though is Pagid discs are junk as that will certainly run with an imbalance
Oh what is clear though is Pagid discs are junk as that will certainly run with an imbalance