Do you have a source for the 14-inch front brake drum for F4-F6? Both sets I have are out of spec, so I'm stalled at the brake&lite certification. I noticed BMORAN4 said last May, "Drums are not available new anywhere." Chuck says, "There's a place I can get them for $450 each, minimum order 5."
Any other ideas? I can weld and turn them if I could find someone to cast the ring and stamp the bolt plate.

 

Any success I've heard of and had is finding used ones (typically on a whole truck) that are in reasonable condition, or finding a local shop willing to turn the drums (even slightly out of spec) and pair them with slightly thicker pads.

On occasion, NumberDummy is able to pull parts out of nowhere, but I presume by now that all NOS drums are long gone.

 

Thank you BMORAN4. I took your idea of putting thicker pads on the brake shoes to the mechanic. He said, "It's more an issue of distributing the heat." He agreed that 20-thousands seems tight but he has to live inside the rule.
Since I have four of these out-of-spec front brake drums, I think I might try building one up with my torch. A friend said I might warp the drum. I'm thinking I would heat the whole drum to 250º - 300º, then build it up alternating sections to let the heat disipate and let me cool down.
??

 

OK, just for discussion, how much heat will build up on the drums? Assuming, of course, you are not hauling loads up and down mountains or making repeated panic stops? I would SWAG far less heat build up than was engineered for the brake system to function with. Are your drums showing heat cracks or just worn beyond specs?

 

Thanks Ray. I'm just out of spec. You wouldn't think that a few thousandths of an inch are making much difference in heat. There's something in the original design that made Ford specify that 21 thousandths beyond 14 inches on the front is unacceptible.

 

So out of curiosity, what does this brake&lite certification actually entail? Do they pull drums, measure drums, inspect lining? I did a slight bit of searching the CA DMV sites and found only mention thereof.

 

My truck is registered in CA, and no one ever looked at it, other than a Sheriff's Deputy verifying the frame number. There was no brake inspection, no light inspection. No inspection at all...

 

Heating up and welding on a brake drum sounds dangerous to me. I'm no mechanical engineer or metallurgist but this sounds like something that wouldn't be done without some fairly sophisticated equipment. If you're not sure you won't ruin the drums I'd be afraid it wouldn't be done properly. I'm a stickler when it comes to brakes. My first rule when getting a vehicle back on the road it to make sure it stops before I get it to go.

I've always wondered about spray welding the inside of brake drums, like they do to scored crankshafts, and then having them turned to spec. I don't know if this would be legal or not. Also, having the resleeved like engine and brake cylinders. Of course there would have to be sleeves available to do it. All of these procedures, I suppose, would have to be certified that they wouldn't fail during the extreme conditions during braking.

 

Ray, yes, the certification requires pulling the drums and measuring the drums and lining.

JR Joe, could it be you had clear title, such that the DMV had historic record of your truck? My F6 is coming from over 30 years in a field and out of the DMV's system: No title or plates. The DMV requires the certifying mechanic is vouching for the completeness of the system, almost like a homemade.
The certification also requires that a production truck's brakes are, "as originally equipped."
That's why I had to have the vacuum brake booster working.

Bob, I agree brakes are most important. I plan to use this truck. Spray welding, then turning sounds interesting...

 

I think Stu said Chuck, at Chucks Trucks, sleeve some hard to replace brake drums, I'm not sure. Here are a few post Stu mentions the possibility of sleeving brake drums. Stu is the guy to ask at this.

https://www.ford-trucks.com/forums/1...l#post10429936

https://www.ford-trucks.com/forums/1...l#post13725520

https://www.ford-trucks.com/forums/1...l#post13603275

 

The biggest issue I'd see with spray welding is how do you make it round and true inside? A brake lathe will not cut hard spots out of a drum or rotor. You would need some sort of grinding wheel to refinish it.

 

My truck was last registered in '79, but I did have a clear title for it. I was unaware of the state's hoops through which you must jump otherwise. But nothing surprises me about CA any more.

Good luck!

 

It always amazes me when the discussion of titling a vehicle comes up how the states differ on their requirements. Some states will pretty much let you pay a fee and get a title as long as you have a bill of sale. Other states give you a full rectal exam. On one hand I wish they would all get together and standardize their procedures but on the other the country seems to like to follow California on every trend and this would mean all the states could be a real PIA to deal with. I understand the reason for some of the requirements to register a vehicle but when dealing with a 50,60,70 year old vehicle many times it's next to impossible to prove it's pedigree because of all the owners and the mechanical changes that have occurred throughout the year.

 

Spray welding is typically called thermal spray in the industry. I too have pondered building up out of spec drums with thermal spray. The problem I see is not a technical one, it is a liability and cost problem. Since brake drums are so tied to vehicle safety the liability of the repair is huge. Determining the settings for thermal spray involves trial and error with testing performed by a metals laboratory, which is expensive. I did a google search for thermal spray repair of brake drums and found several materials that different manufactures list as applicable for brake drum repair. I found no shops in the US, and only one in Australia, that mention repairing brake drums. The website for the Australian company is here: Metal Spraying Surface Engineering Services Melbourne ? Wagma Engineering

 

Just out of curiosity, what would it take to generate enough interest to have reproduciton drums made (for a reasonableish price)? Is there enough need on this board to make it happen?