ConcoursMustang Forums

1st Generation 1964 1/2 - 1973 - Questions & general discussions that apply to a specific year => 1966 Mustang => Topic started by: Morsel on September 25, 2017, 09:27:21 PM

Title: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on September 25, 2017, 09:27:21 PM
I thought I would reach out to all of you because some of you have already done this. I found the threads related to restoration on the two piece original rotors, which all makes sense, but how do you actually take them apart for the restoration process? Also, what about pressing them back together once finished?

Thanks,

Jason
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: CharlesTurner on September 25, 2017, 10:32:52 PM
The studs are pressed through to hold the 2 pieces together.

When you take them apart, be sure to mark the orientation for balance.
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on September 25, 2017, 11:24:59 PM
The studs are pressed through to hold the 2 pieces together.

When you take them apart, be sure to mark the orientation for balance.

Thanks for the response and good reco on taking pictures on orientation of the top plates and probably even the location of the studs, but wondering, do you just hammer the studs out, that's mainly what I was trying to figure out is how to get the studs out, and then how to get them back in when your ready to put them back together... just don't want to ruin anything while doing this.

Thanks,

Jason
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: J_Speegle on September 26, 2017, 12:03:19 AM
Thanks for the response and good reco on taking pictures on orientation of the top plates and probably even the location of the studs, but wondering, do you just hammer the studs out, that's mainly what I was trying to figure out is how to get the studs out, and then how to get them back in when your ready to put them back together... just don't want to ruin anything while doing this.

Use a hydraulic press to remove and replace the studs. Might consider pitting in new studs - your choice.

This does not mean that I haven't beat studs out of axles and hubs (protecting the end and threads)  and reinstalled them using a stack of nuts and washers, just offering a suggestion on how it should be done   ;)
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Bob Gaines on September 26, 2017, 01:03:04 AM
Thanks for the response and good reco on taking pictures on orientation of the top plates and probably even the location of the studs, but wondering, do you just hammer the studs out, that's mainly what I was trying to figure out is how to get the studs out, and then how to get them back in when your ready to put them back together... just don't want to ruin anything while doing this.

Thanks,

Jason
Do not hammer out the studs .You will deform them. Use a hydraulic press as already mentioned.When you put them back together it might be a good idea to put them on a turning machine to true them up rather then find out the hard way after they are installed on the spindle and driving down the road.
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on September 26, 2017, 03:58:53 PM
Thanks everyone for the responses, this is exactly the information I was looking for.

One note and question, it looks like on originals that the studs are Black Phosphate coated, is that correct? I assume I should send those out to be done while I have them out of the rotors.

Thanks,

Jason

Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: J_Speegle on September 26, 2017, 04:37:51 PM
Thanks everyone for the responses, this is exactly the information I was looking for.

One note and question, it looks like on originals that the studs are Black Phosphate coated, is that correct? I assume I should send those out to be done while I have them out of the rotors.

Believe they were heat treated steel of a higher quality so the final look (and the way they come if you purchase them today) dark bare steel. So phosphating or gun blue repair fluid will both replicate the original look
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Bob Gaines on September 26, 2017, 05:28:39 PM
Believe they were heat treated steel of a higher quality so the final look (and the way they come if you purchase them today) dark bare steel. So phosphating or gun blue repair fluid will both replicate the original look
+1
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on September 26, 2017, 05:44:19 PM
Believe they were heat treated steel of a higher quality so the final look (and the way they come if you purchase them today) dark bare steel. So phosphating or gun blue repair fluid will both replicate the original look

Thanks for the info Jeff, I keep seeing you refer to purchasing new, where can you get these studs?

As for using the originals (which is obviously what I prefer to do, definitely know how to blue, but worried about longevity when it's on something that will be getting messed every time I have to take a wheel off. That's why I thought phostophating, but this is not something I do, so would probably have to find a place to send them out to do that, anyone know of any places they are happy with that will do such a small amount of studs?

Thanks,

Jason
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: J_Speegle on September 26, 2017, 06:45:24 PM
Consider that what every you do - when you install the stud into the rotor you remove the coatings though oiling (should be used in both bluing and phosphating may migrate into the area) as will installing the lug nuts so the platings that go on the surface will not be there after they are installed and used except for the ends of the studs and smaller sections. Think more of a dye than a plating/coating would hold up more in this sort of situation.  But your choice
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on September 26, 2017, 08:04:46 PM
Consider that what every you do - when you install the stud into the rotor you remove the coatings though oiling (should be used in both bluing and phosphating may migrate into the area) as will installing the lug nuts so the platings that go on the surface will not be there after they are installed and used except for the ends of the studs and smaller sections. Think more of a dye than a plating/coating would hold up more in this sort of situation.  But your choice

OK, that makes perfect sense and glad I asked, I guess blueing it is then, easier for me anyway ;)

Thanks Jeff,

Jason

Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on October 09, 2017, 09:08:26 PM
OK, back to this, I've had the studs press out and getting ready to clean up the rotors and hubs. Next question, there's some pretty good pitting around the outer Kelsey Hayes hub surface where the wheel sit against the hubs. Has anyone gone to the effort of having just that surface machine turned to get a nice smooth surface, or do you not do that and just go with it as is? All the pictures I've seen these surfaces look to be machined smooth... I have a brake shop that said they could do it, but worry about the integrity of the hub by taking material away...

Thanks,

Jason
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Bob Gaines on October 10, 2017, 01:29:32 AM
OK, back to this, I've had the studs press out and getting ready to clean up the rotors and hubs. Next question, there's some pretty good pitting around the outer Kelsey Hayes hub surface where the wheel sit against the hubs. Has anyone gone to the effort of having just that surface machine turned to get a nice smooth surface, or do you not do that and just go with it as is? All the pictures I've seen these surfaces look to be machined smooth... I have a brake shop that said they could do it, but worry about the integrity of the hub by taking material away...

Thanks,

Jason
How bad are the pits? As thick as the hub is it would take a lot of machining to effect integrity in a measurable amount IMO. If the pits are that deep you may want to consider another hub.  I honestly have never had to machine them very much to clean up the surface.If I was going to the trouble I would want them to look as good as they could. I suppose you will have to decide what is acceptable.
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on October 10, 2017, 12:42:59 PM
How bad are the pits? As thick as the hub is it would take a lot of machining to effect integrity in a measurable amount IMO. If the pits are that deep you may want to consider another hub.  I honestly have never had to machine them very much to clean up the surface.If I was going to the trouble I would want them to look as good as they could. I suppose you will have to decide what is acceptable.

Yes, I shouldn't have to take off much, just was wondering more if anyone else had done this specific thing to the hub portion itself and if there was anything I should be aware of before getting it done, or just live with them pitted or try to find new ones...

Thanks,

Jason
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: 67gtasanjose on October 10, 2017, 12:49:30 PM
Yes, I shouldn't have to take off much, just was wondering more if anyone else had done this specific thing to the hub portion itself and if there was anything I should be aware of before getting it done, or just live with them pitted or try to find new ones...

Thanks,

Jason

This whole process is VERY EASY with a brake drum lathe. A few thousandths of an inch will change virtually nothing. Get into the 10's of thousandths... and you will move the wheel inwards the amount that was removed (outside face of hub). On the inside of the hub that faces the rotor, should you also shave that side, you would move the rotor outwards the amount that was removed. The caliper has more than enough room for a 10 thousandths cut. I cannot imagine regular "pitting" is deeper than 5 thousandths.
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on October 10, 2017, 01:17:15 PM
Thanks guys for the help, I don't think it will change it much, just was checking mainly to see if people had done this, don't think I'll have to shave much off to get it smooth, just really wanted a clean mating surface for the wheel to sit against... definitely will not have to do anything to the back side of the hub and the mating surface there, that looks really clean and good.

Jason
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: 67gtasanjose on October 10, 2017, 01:53:01 PM
Just keep in mind that the original hub & rotor were balanced AFTER they were assembled so mark your (original) rotors as to align it to the same hole in the hub. This mark can be hidden under the stud.

Most are Century Brand or other aftermarket replacements and differ a bit from original rotors. There is another thread discussing those differences.
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on October 10, 2017, 08:18:40 PM
Just keep in mind that the original hub & rotor were balanced AFTER they were assembled so mark your (original) rotors as to align it to the same hole in the hub. This mark can be hidden under the stud.

Most are Century Brand or other aftermarket replacements and differ a bit from original rotors. There is another thread discussing those differences.

Yep, these are original Kelsey Hayes and I plan on re-using everything, just cleaning them up and restoring them. Also thanks for the reminder on aligning original placement, they've been completely documented on orientation prior to removing the studs, so I will be able to put them back together exactly as they were for that exact reason of balancing...

Thanks,

Jason
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Bossbill on October 10, 2017, 11:47:32 PM
Back in the last century they used to offer brake drums separate from hubs. In order to separate the two required a cutter that removed the swaging from the stud.
After you received a new drum you put in new studs and then re-swaged the new studs.
This required two special tools.

See this google book chapter on swaging:
https://books.google.com/books?id=mNIhYSCBfmUC&lpg=PA182&ots=EgTXACUYIF&dq=brake%20drum%20swadging&pg=PA182#v=onepage&q=brake%20drum%20swadging&f=false

The K/H disc brake assembly also has this swaging.
Even pressing out the stud is technically incorrect as the sage enlarges the hole in the hub if it's not cut out first.

The saving grace is that new studs usually work well enough and the clamping loads of the "bolt up" hold the whole thing together.

Just offering this as a history lesson, since I haven't seen a cutter or re-swager in decades.
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: 67gtasanjose on October 11, 2017, 08:19:00 AM
The K/H disc brake assembly also has this swaging.
Even pressing out the stud is technically incorrect as the sage enlarges the hole in the hub if it's not cut out first.

I'm not sure I agree with this statement on the K/H rotor/hub assembly. I am looking at an original example from my 67 that has the "K/H" marking on the button-end of the wheel stud that has absolutely no sign of ever having been "swagged". This rotor/hub has been on this 67 from day-1 of my owning it since '78. The other side I took apart last year and it was also on the car when bought in '78, also with the "K/H" marked studs without any sign of "swagging" on the studs.

I also have on hand a "CENTURY" branded service replacement that does not have the "swagging".

I would like to hear more about this (your claim) since I only have a few examples on hand to use to determine what would typically be "concours" on any K/H original hub/rotors. Hoping to learn more ;)
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Bob Gaines on October 11, 2017, 02:17:00 PM
Fortunately the Ford assemblyline originals, Ford service replacement and the aftermarket Wagner and Raybestos 2 piece rotors pairs that I have on hand  do not have the swagged studs. That swagged stud would make it more difficult in any replacement or restoration scenario unless you had the special tools.   
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: Morsel on October 11, 2017, 05:51:40 PM
Yep, my original untouched Kelsey Hayes rotors didn't have them either...
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: krelboyne on October 17, 2017, 09:24:07 PM
Pretty sure that this is an original 1967 Disc brake rotor. I am showing the KH wheel stud with an 'F' marking for rotors. Does this jibe with all of your findings?
Title: Re: Original two piece disc brake rotors - how do you take apart
Post by: 67350#1242 on October 18, 2017, 12:54:21 PM
It is a good idea to have  lug nuts torqued down onto the studs while you are doing the final trueing up of the rotors.  This will ensure the hub is tight to the rotor and similates actual wheel being bolted up.