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pszikszai
05-18-2007, 07:48 AM
I have some new brake drums and hubs that I am going to use.
As you know the ones on the cars came permanently attached to each other. I don't have the tool they used to do that.
I was thinking of weld tacking them together.
The other option is to just mount them and hope that the lug nuts will keep them in position? If you have experience with this problem,
please advise, comment.
Thanks
Paul

DEEPNHOCK
05-18-2007, 08:18 AM
The proper term is 'swage'.
It is the process of pushing down the slightly exposed knurled section of the lug stud to expand the metal into the hole of the brake drum to lock it securely into place.
On most later model vehicles the brake drum is 'centered' on the axle by a lip that protrudes from the axle that the brake drum center hole indexes on. This lip is not part of the Dana design, so the drum needs to center on the studs (all five).
While the drum may fit on an axle flange that has new studs installed, there will be a small gap between the OD of the stud and the ID of each stud hole. This can cause the drum to be slightly off center when the 5 studs are tightened and can give you a vibration upon brake application.
The 'correct' procedure would be to take the whole flange and drum to an automotive machine shop and have new studs pressed into the hub, have the drum mounted and swaged to the studs, and have a bare minimum clean up pass made on a brake drum lathe,
A lot of times the old drum just gets ripped off the flange unceremoniously and the original 'swaged' studs are left in place. This might cause the gap between the new drum and the studs to be a lot less. In some cases it may fit snugly. While not the recommended OE mounting procedure; it has been done this way successfully many many times. It won't cost you anything to try it and see.
Hope the info helps.
Jeff[8D]



quote:Originally posted by pszikszai

I have some new brake drums and hubs that I am going to use.
As you know the ones on the cars came permanently attached to each other. I don't have the tool they used to do that.
I was thinking of weld tacking them together.
The other option is to just mount them and hope that the lug nuts will keep them in position? If you have experience with this problem,
please advise, comment.
Thanks
Paul


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DEEPNHOCK at Gmail.com
Brooklet, Georgia
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kmul221
05-18-2007, 08:19 AM
The hub & drum were not permanently attached together but rust formed between the two surfaces binding them together.They can be separated by using a rust dissolver only on the affected surfaces & allowing time for it to work,a few gentle taps should then separate the two.Never use excessive force or the hub & drum will be damaged.
The hub fits on the axle by means of a tapered axle end & is held from rotating by a slot in the axle & a Woodrufe Key.A castle nut & cotter pin & washer stop it from coming off.
Be sure to use a correct puller to remove the drum & hub from the axle using caution not to damage the threads on the axle end.One of the other members probably has a link with more info they could post.

Transtar60
05-18-2007, 05:33 PM
The swaging process did bind the two together Kmul.
During swaging material from the studs is displaced and pins the drum to the hub.

Similiar to mechanically items being staked into place.

http://racingstudebakers.com/coppermine/albums/userpics/10056/5E13%20Pic%203.JPG
3E38
4E2
4E28
5E13
7E7
8E7
8E12
8E28
4E2
59 Lark
etc

Dick Steinkamp
05-18-2007, 08:08 PM
quote:Originally posted by kmul221
a few gentle taps should then separate the two.


Probably not if they have actually been swaged. I have taken some apart that have had the studs replaced and either not swaged or poorly swaged. They did come apart fairly easily. For those that are factory swaged or otherwise swaged properly, a press is needed with the stud properly backed up to prevent distorting the drum.

http://thenobot.org/images/s2d/s2d_01.jpg

sbca96
05-18-2007, 09:11 PM
Do NOT tack weld them, the heat will effect the temper of the material
of both the drum and the hub (not to mention seriously distort). The
advice given previously is correct, the shoulders on the studs are
squished or swaged to hold the drum in place. You can have that done
again, try how DEEPNHOCK mentioned, or replace the studs with ones
that have an untouched shoulder that are the same diameter as the 5
holes in your new drums. This is how I centered my Cobra rotors and
it should also work fine for drums (though concentricity is actually
more important on drums than disc brakes).

http://hometown.aol.com/sbca96/images/avantibrakeproject/HubsforCobraRotors/hubs_001a.jpg

http://hometown.aol.com/sbca96/images/avantibrakeproject/HubsforCobraRotors/hubs_017a.jpg

http://hometown.aol.com/sbca96/images/avantibrakeproject/HubsforCobraRotors/hubs_015a.jpg

http://hometown.aol.com/sbca96/images/avantibrakeproject/HubsforCobraRotors/hubs_018a.jpg

http://hometown.aol.com/sbca96/images/avantibrakeproject/HubsforCobraRotors/hubs_022a.jpg

http://hometown.aol.com/sbca96/images/avantibrakeproject/cobra_install/cobra_install021a.jpg

Tom


quote:Originally posted by pszikszai

I have some new brake drums and hubs .....I was thinking of weld tacking them together.

'63 Avanti, zinc plated drilled & slotted 03 Mustang Cobra 13" front disc/98 GT rear brakes, 03 Cobra 17" wheels, GM alt, 97 Z28 leather seats, soon: 97 Z28 T-56 6-spd, Ported heads w/SST full flow valves, 'R3' 276 cam, Edelbrock AFB Carb, GM HEI distributor, 8.8mm plug wires

pszikszai
05-18-2007, 09:11 PM
Thank you all for responding.
I do and did understand the process.
I have new drums but ran out of new factory
sewaged ones.
What result can I expect if I just put the new drum on the
hub and hope that the lug nuts keep it from moving.
If anyone has done that how did it function?

sbca96
05-18-2007, 09:46 PM
Thats kinda been answered. To recap :

1. You might get lucky and whats left of the pre-swaged studs sticks
out far enough to center the drum and all is good, or

2. You put the drum on and the drum is not concentric with the hub
resulting in the most amazing shimmy you have ever felt in your life.
Causing your fillings to rattle out of your head, bubble gum flying
out of your mouth, by a steering wheel shaking so much that you'll be
surprised that it didnt come off in your hands.;)

The lug nuts WILL tighten the drum and wheel down enough to hold it in
place, but you have to make sure that that place is concentric about
the center of the hub, or the drum will move like a cam lobe.[B)]

Tom


quote:Originally posted by pszikszai

What result can I expect if I just put the new drum on the
hub and hope that the lug nuts keep it from moving. If anyone has done that how did it function?