Reply
 
Thread Tools Search this Thread Display Modes
 
Old 11-25-2005, 01:22 PM   #1
Rivet Master
 
JimGolden's Avatar
 
Vintage Kin Owner
1977 31' Excella 500
Berkeley Springs , West Virginia
Join Date: Sep 2005
Posts: 1,619
Images: 7
Disk Brake Assembly Balancing

Hi All,

I've been reading the various threads on balancing of the running gear.

It would seem to me that the best setup would be to balance the hub assembly itself first, independantly of the wheel and tire. Then you'd spin balance the wheel and tire just like you would for your car. Since the two are balanced indendantly, it wouldn't matter how you mount the wheel on the hub.

With disk brakes, how to do this? There's really no place to drill holes in the rotor to safely remove material from the heavy side. Likewise, there's no place to add mallory metal to heavy up the light side? So what to do?

In conversations with some guys who deal in the Kodiak brake systems, they've told me that the hubs/rotors from Kodiak are very close to being balanced as-is.

The idea I had is this: If you need to only remove an ounce or so, couldn't you remove a little off the circumference of the rotor on the heavy side to balance it? This would seem like a logical way to do it. You wouldn't remove enough to get to where the disk pads swipe. You'd probably have to take less than 1/16" off the circumference of the heavy side to get it to balance. Probably more like 1/32". So you'd be left with a rotor that isn't 100% round then, it'd be a wee bit oblong, but it'd be balanced. I would think this would be fine.

Once this is done, the rotating assembly is balanced on its own and you'd not have to fool with the balancing of the wheels/tires/hubs as a single unit. It'd be a bit of work to do this, but it'd be a one time thing. Get them balanced and forget about them. Otherwise, it's a complicated task every time you change tires. And if you mount a spare out on the road, you're out of balance. I think this would really be a good solution, provided the disks weren't out of balance too badly to start with (if they are then this idea probably wouldn't work).

Thoughts?
__________________

__________________
JimGolden is offline   Reply With Quote
Old 11-25-2005, 02:10 PM   #2
Site Team
 
, Minnesota
Join Date: Aug 2003
Posts: 6,940
Images: 59
I think it's a good idea. I would probably agree that the hubs/rotors are going to be much better balanced 'out of the box' than drums.

You could use a different approach if you get separate rotors and hubs, rather than the integral design. With a little trial and error you could match the rotors and hubs so that the heavy side of the hub is opposite the heavy side of the rotor. Then if there is still any residual imbalance you could take it off the outer diameter of the rotor, or off the meat in the hub.

You'd need to mark them so they stay oriented if someone takes them apart.
__________________

__________________
markdoane is offline   Reply With Quote
Old 11-25-2005, 03:39 PM   #3
Rivet Master
 
Bob Thompson's Avatar
 
Corpus Christi , Texas
Join Date: Sep 2003
Posts: 936
Images: 67
If you haven't already considered it, you should give some thought to getting Centramatic automatic balancers. They really are the best ticket to keep your tire/wheel assemblies in perfect balance.
http://www.airforums.com/forum...s-16506-4.html

start at post #55 and read down.
__________________
So Long!
Bob Thompson is offline   Reply With Quote
Old 11-25-2005, 04:19 PM   #4
Rivet Master
 
TomW's Avatar
 
1967 26' Overlander
Huntsville , Alabama
Join Date: Dec 2003
Posts: 2,918
Images: 2
Quote:
Originally Posted by Bob Thompson
If you haven't already considered it, you should give some thought to getting Centramatic automatic balancers...
Be wary if you want to mount them on a vintage Airstream.

Tom
TomW is offline   Reply With Quote
Old 11-25-2005, 07:01 PM   #5
Rivet Master
 
JimGolden's Avatar
 
Vintage Kin Owner
1977 31' Excella 500
Berkeley Springs , West Virginia
Join Date: Sep 2005
Posts: 1,619
Images: 7
I've seen guys on here talk about the centramatics. I'm going to have to study up on them as I don't know anything about them, much less how they work. I've also seen some kind of beads advertised on here that are supposed to be a dynamic balancer of some type too.

I'd be all for a hub/rotor setup like is used on a car where the disk is separate from the hub. Any leads on who offers a setup like that?
__________________
JimGolden is offline   Reply With Quote
Old 11-25-2005, 07:06 PM   #6
Site Team
 
, Minnesota
Join Date: Aug 2003
Posts: 6,940
Images: 59
Quote:
Originally Posted by JimGolden
I'd be all for a hub/rotor setup like is used on a car where the disk is separate from the hub. Any leads on who offers a setup like that?
Kodiak sells both the separate rotor & hub and integral one piece.
__________________
markdoane is offline   Reply With Quote
Old 11-25-2005, 07:39 PM   #7
Rivet Master
 
JimGolden's Avatar
 
Vintage Kin Owner
1977 31' Excella 500
Berkeley Springs , West Virginia
Join Date: Sep 2005
Posts: 1,619
Images: 7
That'd be great. The only Kodiak ads I've seen showed the integral units. I'm going to dig deeper into this.

I read up on the centramatics. Looks good in theory. Looks like it works sort of like the fluidampers I've seen for engines where you've got an inner weight and an outer weight and they're allowed to "slip" to get to what's needed. I have to wonder then, if the beads that you just dump inside the tire wouldn't work about the same as the centramatics? It's the same principle anyway. At any rate, a very good idea on those things.
__________________
JimGolden is offline   Reply With Quote
Old 11-25-2005, 07:57 PM   #8
Site Team
 
, Minnesota
Join Date: Aug 2003
Posts: 6,940
Images: 59
Here's the Kodiak site: http://www.kodiaktrailer.com/redswish/disc_brakes.htm
__________________
markdoane is offline   Reply With Quote
Old 11-25-2005, 08:44 PM   #9
Site Team
 
, Minnesota
Join Date: Aug 2003
Posts: 6,940
Images: 59
if you are interested in balancing powder or beads, search on 'Equal' (no, not the sweetener) and Dyna-beads.
__________________
markdoane is offline   Reply With Quote
Old 11-26-2005, 07:42 AM   #10
Rivet Master
 
2006 30' Classic
Farmington , New Mexico
Join Date: Feb 2005
Posts: 822
Images: 14
Jim --I spent most of my automotive carreer working on front ends syspention systems, brakes etc. Here are some of my observations. It's not likely that you'll ever have a balance problem with a rotor, a drum yes, but due to the way rotors are made it's unlikely. If you take a casting as your raw material and machine all surfaces off a common center it in escence becomes balanced. There could be a difference in the density of the matterial but that would be very slight. Drums are different in that you don't machine the outer surfaces. The most accurate way to balance wheels is to spin <dynamic> balance the wheel and drum or rotor as an assembly. You then have to mark wheel stud and hole so not to loose this balance should the wheel be removed later. The second best is to balance the tire and wheel off the stud center. Most people balanceing wheels today spin the wheel off the WHEEL center which is NOT THE CENTER ON WHICH THE WHEEL ROTATES when on the vehicle. When a wheel is mounted to a hub it rotates off the center the studs create which can be different than the wheel center. There are adapters for most balances that attach the wheel to the balancer by the lug bolt holes. Imagine for example you were to balance off the wheel center then mount it on the vehilcle with the wheel tire assembly off center even a few thousands. The mass of the tire off that small amount will make a HUGE difference in balance. The only problem you'll find doing it this way is it requires more time to balance them this way and most shops don't or won't do it this way unless you insist. Having said all this there is a third way which in most cases is plenty good for trailer wheels. That is static balancing that you can do at home by yourself. Jack up a wheel, loosen brake adjustment and bearing so the wheel will freely rotate. Let the heavy spot of the wheel go to the bottom and counter balance it with weights oposite it by trial and error until the wheel will remain still anywhere you rotate it. If it takes more than a couple ounces to do this I would devide it and put half on the inside. With disc brakes its normally ness. to remove the caliper during this operation. Make sure you mark the wheel and studs so as to reinstall the wheel in the same location should you remove it. Finally and I know some will disagree but when it comes to powders liquids , bolt on balancers, etc, I have found that if it sounds to good to be true it usually is and people tend run from the truth and stand in line to be fooled!!!
Pieman
__________________
Mike Lewis is offline   Reply With Quote
Old 11-26-2005, 09:54 AM   #11
uwe
418
 
uwe's Avatar
 
2007 25' Safari FB SE
1958 22' Flying Cloud
1974 29' Ambassador
Yucca Valley , California
Join Date: Jun 2002
Location: 1963 26' Overlander
Posts: 4,767
Images: 41
Send a message via Skype™ to uwe
Quote:
Originally Posted by JimGolden

I'd be all for a hub/rotor setup like is used on a car where the disk is separate from the hub. Any leads on who offers a setup like that?

Jim, Dexter's heavy duty disc brake setup is a composite system. i have installed it on my 1963 Overlander. You can see it in my thread "a 63 for me".
The discs seem to be balanced very well, with the bearing very loose, the disc stops wherever you turn it to. All my brake drums had heavy spots, they would always find a spot they would gravitate to with a loose bearing and no brake drag.
My Mercedes discs are balanced by removing material from the outside, but not all the way way across. The material is removed by a machine that is narrower than the disc's width. I have seem other rotors having metal clips installed right on the brake vents.
I doubt that a new brake rotor will be out of balance enough to warrant balancing, though.
__________________
Uwe
www.area63productions.com
uwe is offline   Reply With Quote
Old 11-26-2005, 12:09 PM   #12
Rivet Master
 
1994 30' Excella
Mississauga , Ontario
Join Date: Jun 2004
Posts: 939
Jim,
If you remove metal from one side of the rotor would that side not tend to run hotter when braking? There won't be as large a heat sink effect on that side.
Al
__________________
BigAl is offline   Reply With Quote
Old 11-26-2005, 12:21 PM   #13
Site Team
 
, Minnesota
Join Date: Aug 2003
Posts: 6,940
Images: 59
Quote:
Originally Posted by BigAl
Jim,
If you remove metal from one side of the rotor would that side not tend to run hotter when braking? There won't be as large a heat sink effect on that side.
Al
Al,

I'm not sure I follow that. If you are removing metal from the heavy side, you are making it more balanced, from both a weight aspect and a heat sink aspect.

In other words, it may have been running cooler on that side before you balanced it.
__________________
markdoane is offline   Reply With Quote
Old 11-26-2005, 12:27 PM   #14
uwe
418
 
uwe's Avatar
 
2007 25' Safari FB SE
1958 22' Flying Cloud
1974 29' Ambassador
Yucca Valley , California
Join Date: Jun 2002
Location: 1963 26' Overlander
Posts: 4,767
Images: 41
Send a message via Skype™ to uwe
Quote:
Originally Posted by BigAl
Jim,
If you remove metal from one side of the rotor would that side not tend to run hotter when braking? There won't be as large a heat sink effect on that side.
Al
It is a miniscule amount of metal to begin with. More like a deep scratch between the heat fins.
__________________

__________________
Uwe
www.area63productions.com
uwe is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Brake Controllers smily Brakes & Brake Controllers 6 10-02-2002 07:12 AM
Idler arm support assembly PeterH-Airstreamer Mechanics Corner - Engines, Transmission & More... 0 09-11-2002 09:53 PM
Wheel Assembly Balancing CJsTs Wheels, Hubs & Bearings 41 09-11-2002 08:55 PM
Electric Brake Controller Problem Don Brakes & Brake Controllers 4 04-15-2002 02:05 PM
Which brake controller? Andy R Brakes & Brake Controllers 2 03-06-2002 11:11 AM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 12:16 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.