Ford Lockheed (1) Brake Adjustment Aid?

8EL

8EL

Senior Member
What do you guys think if machining a .625" - .750" hole in the face of the brake drum in line (circumference) with the end of the shoe contact face. This would allow viewing from the front of the drum while installed to witness the brake shoe contact with the drum. It could be rotated then to observe the contact along the full peripheral of the shoe, making the shoe adjustments quite simple, and accurate. This would greatly simplify, I believe, setting up the eccentric adjusters on 39-41 types. The 42-48 types are simpler to adjust so this may not be deemed as useful as the previous type, but it would still make this adjustment procedure much quicker and accurate.

For this to work, new linings, or all having the same thickness, and the drum inner diameter the same on all drums would be necessary. In my case, new linings (shoes) and drums are being installed. This would require only machining one drum, as it could be used as a standard gage on the other three.

When all wheels were set up, the hole could be plugged with 100% silicone caulk to hold off water and dirt if that would be an issue. I remember on Bendix brakes there was a oval knock out in either the drum face or backing plate for adjusting the star wheel. This hole in the backing plate sometimes had a rubber plug installed, but most of them were just a hole....didn't seem to hurt anything....
 
So how is your suggestion helpful? I was asking a thoughtful question. If this is the best you can do then don't... By the way still waiting to see how you plumbed wheel cylinders on the top at 0 degrees on model A's with over axle spring mounts......I had sent illustrations of what I had done, the intent here is to share information to improve procedure and solve problems, the sarcasms do nothing toward this end.....
 
8, I think you are doing a lot of unneeded work. The brakes have been working good for almost 100 years.

As a wise man once said "if it ain't broke, don't fix it".

Another wise man said "don't go looking for problems".
 
I believe Jim and old31 have been around model A's enough that they know what they are talking about.
It seems as though most here are certainly not absolute restorers but "if it ain't broke, don't fix it" seems to be the norm.
 
old31 said:
8, I think you are doing a lot of unneeded work. The brakes have been working good for almost 100 years.

As a wise man once said "if it ain't broke, don't fix it".

Another wise man said "don't go looking for problems".
Click to expand...

The brakes are in need of rebuilding, they never worked as good as Bendix self actuating brakes, any mechanic will tell you this. The 39-41 Lockheed brake is a huge pain in the *** to set up properly, they require major adjustment with new lining installation according to the shop manuals I have from the thirties/forties, let alone my own experiences with them. 42-48 was better but not good. So I guess by your analogy "they are broke" therefore "need fixing", I was trying to simplify and improve their performance in so doing. Being able to see what adjustment was needed and then making it would be easier, not harder. The reason I was asking for others opinion was the considerations that I may be overlooking from a structural impact on the strength of the drum. Thinking someone may have tried this (not a terribly far fetched conclusion to draw) and had their experiences to share. Not just stiff arm any new concept because "we always did it this way". or "it worked this way in 1940, why change it now"?. That mindset would have us still riding horses and trimming the wicks on our oil lamps in the evening....

Look at the advancements man has made in the last 100 years....I guess people do not like change, or any purveyor of it.
 
bobv said:
I believe Jim and old31 have been around model A's enough that they know what they are talking about.
It seems as though most here are certainly not absolute restorers but "if it ain't broke, don't fix it" seems to be the norm.
Click to expand...


Guess I have said my bit here, would welcome any constructive criticisms or suggestions, especially from those who may have found a better procedure to follow setting up this style brake, or wish to interject what they know not to work from their experiences.

I guess I can make this analogy in that regard "if it did not work in 1940, then the same experiment will have the same results today".....But first lets make sure it is the same.....
 
I have those on my AV8, simply because I wanted hydraulic brakes and the parts were available. I find them easy to adjust as they are. When I first installed them I covered the shoes with sidewalk chalk (borrowed from my grandkids) and it was easy to see how they were contacting the drums and where a little had to be ground or sanded off. They stop very well now. I believe the the earlier style have eccentrics on the lower pivot point that might permit more adjusting, but mine do not so must be the later style. I don't see how a view hole would help with adjusting. You would probably have to use a feeler gauge to measure any gap. I would think you could do it just as well by feel. Good on you to at least consider the possibility.
 
8EL, I would worry that you are introducing an out of balance condition to your brake drum. The hole would need to give visibility to the contact of the shoe to the drum and would therefore be at the outer edge. This would be the worst for imbalance. I am not familiar with these early hydraulics. I would think you would want to use a "tool drum" for your approach, then store the tool for later use and run 4 undrilled drums. Once you commit to a "tool", then you can make a much bigger window to see inside but this all seems like a tough slog.
Maybe someone has a method that provides good results without a 5th drum? I think the starting point is to have the shoes "arced" to the drums, then adjust when assembled?
Like I said, I am not familiar with these but it is an interesting question.
 
30Murray said:
I have those on my AV8, simply because I wanted hydraulic brakes and the parts were available. I find them easy to adjust as they are. When I first installed them I covered the shoes with sidewalk chalk (borrowed from my grandkids) and it was easy to see how they were contacting the drums and where a little had to be ground or sanded off. They stop very well now. I believe the the earlier style have eccentrics on the lower pivot point that might permit more adjusting, but mine do not so must be the later style. I don't see how a view hole would help with adjusting. You would probably have to use a feeler gauge to measure any gap. I would think you could do it just as well by feel. Good on you to at least consider the possibility.
Click to expand...

This was what I was looking for, excellent idea with the sidewalk chart.....
 
GeneBob said:
8EL, I would worry that you are introducing an out of balance condition to your brake drum. The hole would need to give visibility to the contact of the shoe to the drum and would therefore be at the outer edge. This would be the worst for imbalance. I am not familiar with these early hydraulics. I would think you would want to use a "tool drum" for your approach, then store the tool for later use and run 4 undrilled drums. Once you commit to a "tool", then you can make a much bigger window to see inside but this all seems like a tough slog.
Maybe someone has a method that provides good results without a 5th drum? I think the starting point is to have the shoes "arced" to the drums, then adjust when assembled?
Like I said, I am not familiar with these but it is an interesting question.
Click to expand...

Thought to do just like you say here Gene, the problem being that the old drums were replaced because they were out of spec. So if I made one of these my tool the linings would be too tight on the new drums. I guess I could use a spacer with the oversize old drum that would take up for the wear.... Might just be the way to go, much more comfortable with machining the old drum....
 
So you guys employ a common practice of sanding the new linings to fit the drum? Are you doing this by hand (I would think)?

Thank you all so much for the constructive suggestions, much more helpful than the original responses, much appreciated....This provides value and improves what is being undertaken as it should be.....
 
I don't get to come here often due to time constraints but wanted to comment the OP's idea of a small slot was implemented by other manufacturers that continued to use the first design with Chrysler being one of them. Ammco also made a tool for adjusting the shoes before installing the drums. For me, with 25 years of engineering and 25 year of owning a classic car repair/ resto business, I hated the design. IF one dealt with them on a regular basis, not so bad, but if not, 42-48 and save yourself some grief 🍻
 
I would avoid using the early style backing plates with the lower adjustment. 42-48 is much better. You really need a brake shoe centering tool for the early ones.
 
I put a strip of 80 grit inside the drum and sand the shoe to match the drum. Don't go too far just get the high spots off.
IF you decide to drill a hole do it twice 180 degrees out to keep it balances.
 
I haver a service tool that is for getting the shoes concentric with the drum.
it fits onto the spindle bearings(drum removed) and has a little foot on it , easy to set the shoes up concentric.
Let me know if you want a pic.
Lawrie
 
Later Model A drums were cut away to reveal the innards. But the wheels provided a dust cover. So any hole in the drums should have some way to keep dust and water out.
 
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