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Scott40
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-- 04-24-2012 @ 8:06 PM
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Hello, I’m new to the forum and new to old Fords. I’m working on the brakes of a 1940 Deluxe Tudor I bought recently. Old restoration, and brake system had been neglected for quite some time. Both rear wheel cylinders were leaking and I replaced them with new ones. Still plenty of lining left on the rear shoes, but 3 out of 4 show odd wear patterns. I removed the shoes and determined they were bent. It’s apparent when you look down the edge of the web. The bottom portion of the web, where the large hole for the anchor pin is located, is cocked at a very slight angle to the rest of the web. This not only makes the lining contact the drum at an angle, which accounts for the wear pattern, but also causes the tab at the top of the shoe to press sideways on the slot in the wheel cylinder piston.
I don’t know how the shoes got bent, but think they may have been put on the car that way. Obviously it’s not a good thing and I’d like to replace all 4 rear shoes. Am I better off buying brand new shoes (from C&G for example) or relined shoes? As for lining, which is preferable – molded or woven?
Another question: All shoes on the car, front and rear wheels, have long linings – the rear facing shoes do not have short linings. Other than not being “correct”, is there a problem with this? Does it have an adverse effect on brake performance?
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kubes40
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-- 04-25-2012 @ 6:41 AM
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I have never used reproduction brake shoes so I can't offer any personal experience in regard to their quality (or lack thereof).
Regardless of what you choose for shoes, reproduction or have good cores re-shoed, it is imperative you have the drums turned and the respective shoes arced to the drum(s).
In my opinion, having shoes with all "long" linings will not effect performance in this type of system.
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Stroker
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-- 04-25-2012 @ 7:12 AM
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Since these brake designs have no true "servo", "floating" or self-actuating geometry, incorporated into their design, they simply pivot out in a "V" with the apex at the bottom. The slightly slotted anchor hole is supposed to allow for the leading end of the rear lining to make contact with the drum at the the bottom. Having a shorter lining on the rear simply increases the contact pressure (psi) on the drum/shoe interface. The rear shoe operates at a disadvantage due to the (V) geometry when driving forward, and the front shoe does most of the braking.
I'd like Supereal's take on this, but I tend to agree with Kube in that having long linings on
the rear shoes will not make a noticeable difference in braking efficiency, but might increase
the required pedal force slightly. A softer riveted lining would reduce that effort at the expense of longevity.
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supereal
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-- 04-25-2012 @ 10:20 AM
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Dan: The stock configuration is with the long (primary) shoe facing forward, and the reverse shoe facing to the rear. You will note that the large end of the wheel cylinder connects with the primary shoe. If the shoes are reversed, braking will be considerably reduced. I suspect that they were designed that way to direct the torsional force mostly to the anchor first. If the ends of the shoes are bent, it is likely that someone forgot to reinstall the clips that hold the shoes to the backing plate. Forcing the drum to remove it will cause the shoes to cock enough to catch the drum, making removal very difficult, and resulting in damage to the shoes. As to linings, I prefer the riveted type, as many of the bonded linings are too hard. Woven linings were designed for mechanical braking systems. Before having the drums turned, carefully measure the inside diameter. The original diameter is 12 inches, and the allowable cut is .060. Even then, the shoes must be fitted to the drum. It is a good idea to turn the drums just enough to remove scoring only. Be sure to slightly champfer the edges of the new linings so they will quickly seat. Shops today now do mostly disc brake systems. If you need to have your drums turned, look for a truck shop. Be sure that they use a vibration damping belt around the drums when they are being turned, or it is likely that the surface will be uneven. The long/short shoe configuration is important. One thing you can be sure of is that Henry wasn't about to use it if there wasn't a reason other than to save lining material. In today's traffic, good braking is an absolute requirement. When all others around you have power disc brakes, your old car must have the best you can provide. In my opinion, brakes are the most often neglected part of older vehicles.
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kubes40
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-- 04-25-2012 @ 3:07 PM
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Dan, You have now heard from the best in my opinion. I'll take third out of the three that have responded thus far.
I may with respect disagree that it makes much difference if you have two "long" shoes. however, why chance it? You will obviously need to get new shoes.Just be certain to get the longs and shorts.
Please, go to the trouble of finding someone to arc the shoes. HUGE difference in performance.
Mike
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Scott40
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-- 04-25-2012 @ 7:05 PM
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Thanks, everyone. I appreciate all your helpful responses. Will definitely take your advice!
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supereal
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-- 04-26-2012 @ 9:22 AM
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Thanks, Mike. The reason that the long-short shoe configuration was designed was to stage the application of the brakes so the action will be even, and locking the wheels can be avoided. This Lockheed system was successful until the adoption of the "self energizing" Bendix arrived in late '48. One of my first jobs at a Ford dealer was on the "brake rack". In those days, brake linings contained asbestos, and it was common practice to blow the dust off with compressed air. Today, we use a water hose. Sadly, most of the men whom I worked with in the 50's died of lung cancer. I can only speculate that it was connected to the dust, probably aggravated by the heavy smoking that was usual in those days. The modern "organic" lining materials now used don't last as long as the original type, but at least they don't kill you!
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kubes40
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-- 04-26-2012 @ 9:32 AM
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Hey Super, I too had done literally 100's of brake jobs back when there was not a thought in regard to blowing the dust away.
So far I have good lungs. I hope that remains true 
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Stroker
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-- 04-26-2012 @ 11:00 AM
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Most of us who "wrenched" in the 50's & 60's probably got a good dose of asbestos dust
blowing out brake drums and pressure plates. The last time, (70's) I had my 38 drums
turned, I asked the shop to arc the shoes. The shop foreman pointed to the arc'ing
machine squirreled away on a top shelf, and said he'd let me use it, as long as I took it to my shop to do it.
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ford38v8
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-- 04-26-2012 @ 12:33 PM
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Getting off topic here, but I worked for General Electric, at a manufacturing plant until 1979, in which you could smell the asbestos dust. It was so thick in the air, you couldn't see through the shafts of sunlight from the skylights, for the sparkles of asbestos. Workers had personal fans to blow the dust away from their own workstations onto someone elses.
Those were the days that the general public still had a measure of trust in Government and Corporate paternalism. Ge had at that time been in violation of the Toxic Substances Act for 3 years, and the ban on asbestos itself was overturned 15 years later.
Am I bitter? No, I think it's a good thing that we are not as trusting as we once were. We have to watch out for ourselves, as nobody else is going to do it for us.
Alan
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kubes40
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-- 04-26-2012 @ 1:54 PM
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Stroker, I served two apprenticeships in my life. Tool & Die and Automotive Machinist.
The first (auto) was when I was in my early 20's. Never gave a thought to arcing shoes. At the same time, I owned my own service garage and would always arc the shoes for the brake jobs I was doing.
My gosh, 100's of brake jobs. Multiply that by 8 shoes... suddenly I think I don't feel so good
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supereal
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-- 04-27-2012 @ 9:58 AM
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The insidious part of asbestos contamination is a form of cancer called "mesothelioma". It lies dormant for many years, and can appear in late life. Those of us old guys may not yet be "out of the woods". Asbestos abatement was ridiculed years ago as just another government overreach, as it appears in so many places. Many of us grew up in old houses where the furnace and heating ducts were wrapped in the stuff. Old shops were full of substances we now know as harmful, such as carbon tetrachloride, used in fire extinguishers and as a solvent that is readily absorbed thru the skin. Just to be on the safe side, use the water hose to clean old brake assemblies, instead of the air hose.
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